Biopolymer, and system and method for producing biopolymer

Abstract

Disclosed is a biopolymer synthesised from a biowaste substrate (102, 204, 304) comprising at least one of: a cellular biomass and an acellular material; and a supplementary substrate, wherein, when grown under optimal process conditions, the yield and physicochemical properties of the biopolymer is regulated by the concentrations of the biowaste substrate, the supplementary substrate and the process conditions.

Description

[0001] BIOPOLYMER, AND SYSTEM AND METHOD FOR PRODUCING BIOPOLYMER

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to biopolymers. Moreover, the present disclosure relates to systems for producing biopolymers. Furthermore, the present disclosure relates to methods for producing biopolymers.

[0004] BACKGROUND

[0005] The global demand for an efficient bioplastic solution has become increasingly urgent due to the adverse effects of traditional plastics on the environment and human health. Generally, these plastics release harmful molecules upon degradation thereof. Such harmful molecules pose risks to human health, including endocrine disruption, cancers due to carcinogens, and fertility issues. For example, a plastic product may be broken down into a microplastic and eventually into a nano-plastic. In such cases, the nano-plastic accumulates in the environment and ultimately enters into living bodies. Notably, despite global efforts to increase recycling rates, plastic waste continues to plague natural habitats, leading to the degradation of ecosystems and contributing to ocean acidification.

[0006] There are currently bioplastics (such as Polyhydroxyalkanoates) that use brewery malt waste and waste cooking oil as raw materials. However, said bioplastics do not have the potential for large-scale production. There are also other bioplastics that are manufactured using plant oils, as well as those derived from simple and complex sugars from food crops cultivated expressly for this purpose. However, such bioplastics do not utilise waste materials or defined sugar media and furthermore also present a dilemma in that farmland and crops are potentially diverted for use in such bioplastics to the detriment of the food supply. Although certified for food contact applications in various regions, the absence of waste material utilisation and collection infrastructure thereof, along with the potential environmental concerns associated with sugar media sourcing ends up limiting the overall effectiveness thereof. Additionally, other bioplastics derived from dextrose obtained from corn cassava, sugar beet, sugarcane, potatoes and wheat have been developed. Said bioplastics are derived from mono, oligo, and polysaccharides. Said bioplastics use a water-based extraction technology without the use of solvents or enzymes. However, said bioplastics are expensive to produce and have a low mechanical strength.

[0007] Conventionally available bioplastics use an expensive standard media for production thereof. However, said standard media makes scaling up production economically and environmentally unsustainable. Moreover, the inherent variability in material characteristics and properties poses significant challenges in terms of their material cost and reproducibility. Consequently, there remains a significant need for an improved bioplastic that offers a more effective approach in order to address the harmful environmental impact of traditional plastics.

[0008] Therefore, in light of the foregoing discussion, there exists a need to overcome the aforementioned drawbacks.

[0009] SUMMARY

[0010] The aim of the present disclosure is to provide a biopolymer, a system and a method to utilise waste materials and reduce plastic pollution. The aim of the present disclosure is achieved by a biopolymer, a system and a method for producing a biopolymer as defined in the appended independent claims to which reference is made to. Advantageous features are set out in the appended dependent claims. Throughout the description and claims of this specification, the words "comprise" , "include", "have", and "contain" and variations of these words, for example "comprising" and "comprises" , mean "including but not limited to", and do not exclude other components, items, integers or steps not explicitly disclosed also to be present. Moreover, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0011] BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 is an illustration of a process of biosynthesising poly(gamma glutamic acid), in accordance with an embodiment of the present disclosure;

[0013] FIG. 2 is an illustration of a process of biosynthesising bacterial cellulose, in accordance with an embodiment of the present disclosure;

[0014] FIG. 3 is an illustration of a process of biosynthesising a Poly(hydroxyalkanoate), in accordance with an embodiment of the present disclosure; and

[0015] FIG. 4 is an illustration of a flowchart of a method for producing a biopolymer, in accordance with an embodiment of the present disclosure.

[0016] DETAILED DESCRIPTION OF EMBODIMENTS

[0017] The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. Although some modes of carrying out the present disclosure have been disclosed, those skilled in the art would recognize that other embodiments for carrying out or practising the present disclosure are also possible. In a first aspect, the present disclosure provides a biopolymer synthesised from a biowaste substrate comprising at least one of: a cellular biomass and an acellular material; and a supplementary substrate, wherein, when grown under optimal process conditions, the yield and physicochemical properties of the biopolymer are regulated by concentrations of the biowaste substrate, the supplementary substrate and the process conditions.

[0018] According to the first aspect of the present disclosure, the aforementioned biopolymer is biodegradable and thus provides a sustainable and environmentally friendly alternative to plastic materials. The biopolymer utilises the biowaste substrate in order to address waste management and reduce production costs. The biopolymer comprises the supplementary substrate in order to provide optimal growth conditions, leading to improved yield and properties of the biopolymer. Additionally, the regulation of concentrations and process conditions enables precise control over the biopolymer's characteristics, allowing for industrial scalability, economic scalability due to favourable costs, environmental sustainability, and the production of biopolymers with tailored properties suitable for various applications.

[0019] In a second aspect, the present disclosure provides a system for producing a biopolymer comprising a fermenter configured to grow an inoculum of biowaste substrate with the supplementary substrate to produce the biopolymer.

[0020] According to the second aspect of the present disclosure, the aforementioned system employs the fermenter in order to support the growth of microorganisms. The fermenter allows for the efficient cultivation of the inoculum, which serves as a starting point for the production process of the biopolymer. Moreover, the system can optimise growth conditions, such as temperature, pH, and nutrient availability, to promote the growth of the desired microorganisms. The system utilises the biowaste substrate along with the supplementary substrate in order to contribute to waste management and promote sustainability by converting waste into valuable products.

[0021] In a third aspect, the present disclosure provides a method for producing a biopolymer of the first aspect, the method comprising: preparing a biowaste substrate comprising at least one of: a cellular biomass and an acellular material; adding the biowaste substrate to a supplementary substrate in a fermenter; growing the biowaste substrate in the supplementary substrate under optimal process conditions; and isolating the biopolymer from the supplementary substrate.

[0022] According to the third aspect of the present disclosure, the aforementioned method provides a sustainable and efficient process for biopolymer production. The method utilises readily available organic materials that would otherwise be considered waste by preparing the biowaste substrate. The method allows the addition of the biowaste substrate to the supplementary substrate in the fermenter, creating a synergistic effect. In this regard, the fermenter provides a controlled environment for optimal growth conditions, ensuring the efficient cultivation of the biowaste substrate. Further, this synergistic approach means that a lower amount of the biowaste substrate and the supplementary substrate are required to achieve optimal productivity. The supplementary substrate complements the biowaste substrate by providing additional nutrients and energy sources, promoting the growth and productivity of the microorganisms responsible for biopolymer production. The method allows for isolating the biopolymer from the supplementary substrate ensuring the separation and purification of the desired product. Said step allows for the recovery of the biopolymer whilst leaving behind any remaining substrate components or impurities.

[0023] Throughout the present disclosure, the term "biopolymer" as used herein refers to a polymer that is derived from living organisms or biological sources. The biopolymer is composed of repeating subunits or monomers, that are naturally occurring molecules. The monomers are covalently bonded in chains to form larger molecules. Examples of biopolymers include proteins, nucleic acids (such as deoxyribonucleic acid (DNA) and ribonucleic acid (R.NA)), polysaccharides, and polyesters found in living organisms.

[0024] The term "biowaste" as used herein refers to waste materials or by-products of a biological process or entity, that typically originate from biological sources, such as living organisms, plants, animals, or by-products of human transformation thereof for its most common anthropic use. Examples of the biowaste may include organic waste, agricultural residues, food waste, and so forth. In an example, the biowaste may be obtained from a whole seaweed or a part thereof, an invasive seaweed (seaweed not native to a particular area), a cast seaweed (that has washed up on shore). In the above example, the cast seaweed may serve as a by-product of the seaweed and may be used for a variety of anthropic uses such as fertiliser, animal feed and biogas production.

[0025] The term "biowaste substrate" as used herein refers to a substance that serves as a source for the synthesis of the biopolymer. Optionally, the biowaste substrate provides the necessary components or building blocks from which the biopolymer is formed. The term "cellular biomass" as used herein refers to a collection of natural, non-chemically engineered living cells or microorganisms present in a biological material. Optionally, this includes various types of cells, such as plant cells, animal cells, or microbial cells. Cellular biomass serves as a potential substrate for the synthesis of the desired biopolymer.

[0026] The term "acellular material" as used herein refers to a biological substance that does not contain cells. Optionally, the acellular material can be extracellular components, such as a plant cell or a microbial cell wall remnant, extracellular matrix materials, or other biological materials devoid of living cells. In this regard, the acellular materials can also serve as a substrate for the production of the biopolymers.

[0027] Optionally, the biowaste substrate can be composed of either the cellular biomass or the acellular material, thus providing a versatile and sustainable approach to the synthesis of the biopolymers.

[0028] Optionally, the cellular biomass of the biowaste substrate is selected from a bacterium or an algae, preferably, a seaweed by-product. Bacterium: The term "bacterium" as used herein refers to a single-celled microorganism belonging to a domain bacteria. Notably, the bacteria are prokaryotic organisms having a wide range of shapes, including spherical (cocci), rod-shaped (bacilli), and spiral (spirilla). The bacteria are ubiquitous in nature and can be found in various environments such as soil, water, and the human body.

[0029] Optionally, the selection of a bacterium as the cellular biomass expands the potential range of which biopolymers can be synthesised. For example, bacterial cellulose has an exceptional mechanical strength and water-holding capacity, and thus can be used in biomedical applications such as tissue engineering and wound healing.

[0030] Herein, the biowaste substrate comprises the cellular material obtained as a seaweed by-product or a seaweed biowaste. The term "seaweed" (namely, a macroalgae) as used herein refers to a type of marine plant that grows in coastal areas and bodies of water. Herein, the term "seaweed by-products" refers to residual materials or components obtained during the processing or extraction of commercially valuable substances from seaweed. Examples of the seaweed by-products may include various components such as cellulosic materials, alginates, proteins, and other organic compounds, obtained from the seaweed, such as algae. Optionally, the seaweed by-product is an algal by-product. In an example, when extracting carrageenan (namely, a hydrocolloid), from red seaweed, the remaining residual material can be considered a seaweed by-product. Optionally, the seaweed by-product is a brown seaweed or a green seaweed. Optionally, the brown seaweed or the green seaweed can comprise fractions of non-seaweed material introduced for process enabling such as processing aids, filtering aids, activation agents, and so forth. Optionally, the filtering aids include but are not limited to diatomaceous earth and perlite. Optionally, the seaweed by-product, including minerals and salts, when it is invasive or cast, can be considered a waste due to poor valorisation potential in the common industrial streams, thus making cast ulva, sargassum, and so forth, eligible as waste. It will be appreciated that the whole seaweed system has pollution reduction potential as it does not lead to generation of halocarbons and methane from a decomposing biomass. Beneficially, the seaweed by-product or a seaweed biowaste serves to produce a crude biopolymer product that has better properties as compared to polymers produced using standard substrates. In this regard, the biopolymer synthesized from seaweed-based biowaste substrate provides improved UV protection, improved metal chelation, and improved hygroscopicity which make the process more suitable for industrial applications.

[0031] Optionally, the selection of a seaweed by-product as the cellular biomass diversifies the feedstock and contributes to a sustainable and economically viable biopolymer production. It will be appreciated that the seaweed is a renewable resource that can be sustainably cultivated, thus providing an environmentally friendly alternative to other biomass sources. Optionally, seaweed has a high growth rate, requires minimal land and freshwater resources, and has a positive impact on marine ecosystems. Typically, seaweed contains various bioactive compounds, such as alginates, carrageenans, furcellaria, agar, ulvan and fucoidans, which have unique properties suitable for applications in food, pharmaceuticals, and cosmetics.

[0032] Optionally, the bacterium is selected from at least one of: genus Bacillus, genus Gluconoacetobacter, genus Ralstonia. The term "genus Bacillus" refers to a genus that belongs to a phylum Firmicutes and comprises a diverse group of rod-shaped, gram-positive bacteria. Notably, the Bacillus species possesses the ability to form endospores which allow the Bacillus species to survive harsh environmental conditions. In an example, a Bacillus subtilis species is used in the production of enzymes, antibiotics, and biodegradable plastics, due to the robust growth and metabolic capabilities thereof.

[0033] The term "genus Gluconoacetobacter" as used herein refers to a genus of gram-negative bacteria belonging to the family Acetobacteraceae. Genus Gluconoacetobacter bacteria possess the ability to oxidise glucose and produce gluconic acid as a metabolic by-product. Optionally, Gluconoacetobacter species are commonly found in natural environments such as fruits, flowers, and vinegar fermentation processes.

[0034] The term "genus Ralstonia" refers to a genus of gram-negative bacteria belonging to the class Betaproteobacteria. Genus Ralstonia bacteria possess the ability to produce polyhydroxyalkanoates (PHA), a type of biopolymer with applications in biodegradable plastics. Optionally, the bacterium may be selected from at least one of the genuses Bacillus, Gluconoacetobacter, or Ralstonia, thus providing flexibility in choosing the specific bacterium as required for the synthesis of the biopolymer. This allows for the utilisation of different bacterial species with diverse metabolic capabilities and properties. Optionally, the bacterium may be selected from at least one of Bacillus subtilis natto, Bacillus lichen! formis, Gluconoacetobacter xylanus, and other species of the Gluconoacetobacter genus, Ralstonia eutropha and other species of the Ralstonia genus.

[0035] Optionally, the algae is a macroalgae selected from Agarophytes, Carraghenophytes, Rhodophytes, Chiorophytes, Prasinodermophyta and Phaeophyceae. Herein, the term " macroalgae" refers to large, multicellular marine algae visible to the naked eye. Typically, the macroalgae are found in marine environments and play crucial ecological roles. Optionally, macroalgae are known for rapid growth and high biomass production therefrom. Herein, the term "agarophytes" refers to a group of macroalgae that produce agar, a polysaccharide with gel-forming properties. Optionally, the Agar finds applications in industries such as food, pharmaceuticals, and biotechnology. Optionally, the inclusion of the agarophytes allows for the utilisation of macroalgae species that can contribute agar or other beneficial compounds to the biopolymer synthesis process. Herein the term "carraghenophytes" refers to another group of macroalgae that are known for producing carrageenan that is a hydrocolloid. Notably, the carrageenan exhibits thickening, stabilising, and gelling properties, thereby making it valuable in various industrial applications.

[0036] Herein, the term "green algae and brown algae" refers to two broad groups of macroalgae. Green algae encompass a diverse range of species belonging to the Chlorophyta group that contain chlorophyll and other pigments, giving them a green coloration. Brown algae species include large seaweed in the Phaeophyceae group, found primarily in colder marine environments. Optionally, brown algae are characterised by a brownish coloration due to the presence of pigments such as fucoxanthin. It will be appreciated that both green algae and brown algae offer unique compositions and properties that can be harnessed for the biopolymer synthesis.

[0037] The technical effect of selecting the macroalgae from at least one of the Agarophytes, Carraghenophytes, Rhodophytes, Chiorophytes, and Phaeophyceae algae is that it enables the incorporation of specific polysaccharides and bioactive compounds into the biopolymer.

[0038] Optionally, the biowaste substrate is a hydrocolloid-extracted biowaste substrate. The term " hydrocolloid'' as used herein refers to a compound that forms a gel or viscous solution when mixed with water. Generally, hydrocolloids are found in natural sources, such as seagrass and algae, and have a wide range of applications in industries such as food, pharmaceuticals, and cosmetics. In this regard, the hydrocolloid is extracted or isolated from the biowaste substrate using a suitable extraction technique. Optionally, the hydrocolloid-extracted biowaste substrate possesses functional properties, such as gelling, thickening, and stabilising. Hydrocolloids can contribute specific functionalities, such as improved texture, stability, or emulsifying properties, to the biopolymer matrix. Therefore, using a hydrocolloid-extracted biowaste substrate allows for the customization of biopolymer properties based on the specific hydrocolloid composition present in the substrate.

[0039] It will be appreciated that instead of discarding the entire biowaste substrate, the hydrocolloid is extracted therefrom in order to ensure the maximum utilisation of the biowaste substrate. Said approach aligns with sustainability goals by minimising waste generation and reducing the overall ecological footprint.

[0040] The term "supplementary substrate" as used herein refers to an additional material or biomass introduced into the biopolymer synthesis process alongside the biowaste substrate. Notably, the supplementary substrate is incorporated to provide additional nutrients, precursors, or other essential components that enhance the synthesis of the biopolymer.

[0041] Optionally, the supplementary substrate may contain nutrients, such as carbon sources, nitrogen sources, or mineral salts, which are essential for the growth and metabolism of the microorganisms involved in biopolymer synthesis. Optionally, the nutrients may act as precursors for the biosynthesis of the biopolymer and contribute to its yield and properties. Optionally, the supplementary substrate may serve as a co-substrate for co-metabolism. The supplementary substrate, by interacting with the biowaste substrate, may facilitate the desired metabolic reactions for optimal biopolymer production. Optionally, the supplementary substrate may act as an inducer or stimulant for the synthesis of the biopolymer. Optionally, the supplementary substrate can also modulate the final physicochemical composition of the biopolymer. Herein, the physicochemical properties of the biopolymer refer to the measurable characteristics and behaviours that arise from the combined effects of its physical and chemical attributes. The physicochemical properties encompass a wide range of factors, such as molecular weight, molecular structure, solubility, swelling behaviour, gelling ability, thermal responses, mechanical performance, rheological behaviour, hydrophilicity, hydrophobicity, chemical stability, and reactivity. Notably, understanding and analysing the physicochemical properties are crucial for tailoring the biopolymer's behaviour and functionality to specific applications thereof. In this regard, under optimal process conditions, the yield and physicochemical properties of the biopolymer are regulated by the concentrations of the biowaste substrate, the supplementary substrate, and the process conditions. This implies that by controlling the concentrations of both the biowaste substrate and the supplementary substrate, along with optimising the process conditions such as temperature, pH, and incubation time, it is possible to regulate and fine-tune the yield and physicochemical properties of the synthesised biopolymer.

[0042] Optionally, the supplementary substrate is rich source of at least one of: sucrose, simple sugars, L-glutamic acid, glucose, waste oil, perlite waste from the extraction of hydrocolloids, metals ions selected from sodium ion, manganese ion, magnesium ion, zinc ion, and iron ion, and monosodium glutamate. In this regard, the presence of compounds such as sucrose, simple sugars, L-glutamic acid, and glucose in the supplementary substrate provides a rich source of nutrients for the microorganisms involved in synthesis of the biopolymer. It will be appreciated that the aforementioned compounds serve as energy sources, carbon precursors, and building blocks for the biosynthesis of the biopolymer. Moreover, optionally, a supplementary substrate containing waste oil and metal ions such as sodium ions, manganese ions, magnesium ions, zinc ions, and iron ion may act as co-substrates or co-factors, leading to co-metabolism and synergistic effects. Optionally, the co-metabolism occurs when the microorganisms utilise multiple substrates simultaneously, resulting in increased biopolymer yield or improved properties. Optionally, the presence of the aforementioned metal ions can also influence enzymatic activities and promote desirable biochemical reactions in the synthesis process. Optionally, the supplementary substrate is a rich source of minerals, oxides, proteins, and pigments. Optionally, the supplementary substrate is used as a biostimulant, a fertiliser, an iodine supplement, and so forth.

[0043] Notably, monosodium glutamate (MSG) may be broken down by the microorganisms involved in synthesis of the biopolymer. MSG is utilized as a nutrient source for growth and energy production. Moreover, glutamic acid, from which MSG is derived, can be used to create biodegradable polymers, such as polyglutamic acid (PGA). PGA is biocompatible and may be useful in medical applications, such as drug delivery systems and tissue engineering. Additionally, polymers derived from glutamic acid can form hydrogels that may be useful in biomedical applications, including wound dressings, due to their ability to absorb large amounts of water and provide a moist environment for healing. Furthermore, carboxyl groups in glutamic acid can be used to introduce functionality into polymers, such as cross-linking, which enhances the mechanical properties and stability of polymeric materials.

[0044] Optionally, in an example, the inclusion of L-glutamic acid may influence the chemical structure and functionality of the biopolymer, leading to desired properties such as increased water solubility or improved film-forming abilities. Optionally, the presence of metal ions can also contribute to the crosslinking or stabilisation of the biopolymer matrix, resulting in enhanced mechanical or thermal properties.

[0045] Optionally, the supplementary substrate is obtained from a pure source or an industrial waste source. In this regard, the use of a pure source as the supplementary substrate ensures a controlled and standardised composition of the substrate. Optionally, the use of the pure source allows for the precise manipulation of the nutrient content and other desired compounds present in the substrate.

[0046] Optionally, the industrial waste source, such as by-products from various manufacturing processes, including spent motor and frying oil, can be rich in organic compounds and other valuable components. Beneficially, repurposing the industrial waste source as the supplementary substrate not only reduces waste and promotes sustainability, but also provides a cost-effective solution for obtaining the necessary nutrients necessary for biopolymer synthesis. Additionally, using waste sources aligns with the principles of a circular economy, as it allows for the valorization of resources that would otherwise be discarded. Optionally, the biopolymer is selected from at least one of: polyfgamma glutamic acid), bacterial cellulose and poly(hydroxyalkanoates), or derivatives thereof. The term "Poly(gamma glutamic acid)'' (G-PGA) as used herein refers to a naturally occurring biopolymer produced by certain bacteria. G-PGA possesses excellent water solubility, biocompatibility, and biodegradability. G-PGA is used in various fields such as food, cosmetics, and pharmaceuticals due to its gelling, emulsifying, and drug delivery properties.

[0047] The term "bacterial cellulose" (BC) refers to a biopolymer that is produced by certain bacteria and exhibits exceptional mechanical strength, high purity, and biocompatibility. Optionally, the bacterial cellulose possesses a unique three-dimensional nanofibrous structure, that makes it suitable as a reinforcement material in composites.

[0048] The term "Poly(hydroxyalkanoates)" (PH A) as used herein refers to a family of biopolymers synthesised by microorganisms as storage compounds. Optionally, Poly(hydroxyalkanoates) exhibit properties such as biodegradability and thermoplasticity. Beneficially, PHA has potential applications in packaging materials, biomedical devices, and agricultural films.

[0049] The term "derivatives" as used herein refers to materials and substances derived from biopolymers selected from at least one of: poly(gamma glutamic acid), bacterial cellulose and poly(hydroxyalkanoates). Notably, the biopolymers serve as the starting materials or precursors for the production of various derivative products through chemical, enzymatic, or mechanical processes. Herein, the precursor compound is transformed into more complex or functionally different molecules through processes like oxidation, reduction, hydrolysis, or synthesis. The derivatives, based on the three biopolymers, poly(gamma glutamic acid), bacterial cellulose and poly(hydroxyalkanoates), have some of the components of the seaweed by-product fraction which can greatly improve the economics and their properties in a relevant environment.

[0050] Optionally, the optimal process condition comprises: a pH of 4-7; a fermentation temperature of 25-37 °C; a fermentation time period of 1-21 days; and a dissolved oxygen concentration above 30%.

[0051] In this regard, the optimal process conditions provide the necessary environmental parameters to support the growth of microorganisms and optimise the production of the biopolymer. Optionally, each parameter range is selected based on the specific requirements of the biopolymer being synthesised, taking into account factors such as pH sensitivity, temperature preference, fermentation duration, and oxygen requirements.

[0052] Optionally, the pH is in a range of 4.0, 4.5, 5.0, 5.5, or 6 up to 4.5, 5.0, 5.5, 6.0, 6.5, or 7. Optionally, the specified pH range of 4-7 ensures a suitable environment for microbial growth and optimal enzymatic activity, facilitating the synthesis of the biopolymer. Optionally, the fermentation temperature is in a range of 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C or 36°C up to 26°C, 27°C, 28°C, 29°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C or 37 °C. Suitably, the for bacterial cellulose and poly(hydroxyalkanoates) (PHA), the ideal fermentation temperature range is around 30 °C, which promotes the growth of bacteria responsible for producing these biopolymers. Suitably, for poly(gamma glutamic acid), the optimal fermentation temperature range is 37 °C.

[0053] Optionally, the fermentation time period is in a range of 1, 5, 10, 15 or 20 days up to 5, 10, 15, 20 or 21 days. Typically, the bacterial cellulose requires a longer fermentation period ranging from 7 to 21 days. Notably, the production of the G-PGA and the PHA can be completed in a shorter time period of 24 to 116 hours, preferably 48 to 116 hours, and preferably 96 hours. Beneficially, the duration of fermentation is optimised to ensure sufficient growth and accumulation of the desired biopolymer whilst maintaining an efficient and cost-effective production process.

[0054] Additionally, an adequate dissolved oxygen concentration is crucial for microbial growth and metabolism during fermentation. In this regard, maintaining the dissolved oxygen concentration above 30% ensures sufficient oxygen supply to the microorganisms, promoting their growth and synthesis of the biopolymer.

[0055] Optionally, the optimal process condition further comprises: an agitation of 100 to 1000 rpm for production of poly(gamma glutamic acid) and poly(hydroxyalkanoates), or a static condition for production of bacterial cellulose.

[0056] In this regard, for the production of the poly(gamma glutamic acid) and the poly(hydroxyalkanoates), the fermentation process requires agitation within the range of 100 to 1000 rpm. Optionally, the agitation is in a range of 100 rpm, 200 rpm, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm or 900 rpm up to 200 rpm, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm or 1000 rpm. Optionally, the agitation speed can be set between 100 rpm and 1000 rpm, allowing for flexibility in optimising the fermentation conditions. For example, the agitation helps in mixing the culture and providing sufficient oxygen supply to the microorganisms, thus enhancing the production of the biopolymers. Optionally, the mode of agitation is mechanical, for example via a mechanical stirrer, or through physical bubbling.

[0057] Optionally, for the production of the bacterial cellulose, a static condition is preferred, meaning that no agitation is applied to the culture during the fermentation. Optionally, the static condition enables the bacteria responsible for producing the bacterial cellulose to grow and form a three-dimensional structure without disruption. Beneficially, the optimal process conditions ensure the desired quality, yield, and characteristics of the biopolymers, optimising the overall efficiency and effectiveness of the production of the biopolymer.

[0058] Optionally, the biowaste substrate is subjected to sterilisation at a predefined temperature for a predefined period of time, wherein the sterilisation includes any of: boiling heating or irradiation of the biowaste substrate, or adding a dissolving sterilisation agent to the biowaste substrate. In this regard, the biowaste substrate used in the production of the biopolymer undergoes sterilisation at the predefined temperature for the predefined period of time. Optionally, the biowaste substrate is sterilised by boiling or heating thereto. Optionally the biowaste substrate is sterilised via irradiation. Beneficially, irradiation saves energy compared to the boiling or heating methods. Optionally, a dissolving sterilisation agent, such as sodium percarbonate, is added to the biowaste substrate. It will be appreciated that the sterilisation eliminates any potential contaminants or unwanted microorganisms present in the biowaste substrate, ensuring a clean and controlled environment for the biopolymer production process.

[0059] Optionally, the biowaste substrate is subjected to heating in the form of autoclaving at an autoclaving temperature of 100-130 °C, preferably 115 °C, under a pressure of 0-3 bar, preferably 2 bar, for a time period of 1-60 minutes, preferably 20 minutes. Herein, the term "autoclaving" refers to a sterilisation technique that involves subjecting the biowaste substrate to a high temperature and pressure in an autoclave. Optionally, the biowaste substrate is subjected to heating at the autoclaving temperature in a range of 100 °C, 105 °C, 110 °C, 115 °C, 120 °C or 125 °C up to 105 °C, 110 °C, 115 °C, 120 °C, 125 °C or 130 °C, preferably 115 °C. Optionally, the biowaste substrate is subjected to heating under pressure in a range of 0 bar, 1 bar or 2 bar up to 1 bar, 2 bar or 3 bar, preferably 2 bar. Optionally, the biowaste substrate is subjected to heating for the time period in the range of 1 minute, 5 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes or 50 minutes up to 5 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes or 60 minutes, preferably 20 minutes. It will be appreciated that the autoclaving is a reliable and efficient technique for achieving sterilisation, as it can penetrate the biowaste substrate and effectively eliminate a wide range of microorganisms. Further, analogous productivity and characteristics can also be achieved in non-sterile conditions by ensuring fine tuning of the fermentation conditions and microorganism pool.

[0060] In an embodiment, the biowaste substrate is comprised of post hydrocolloid extracted biomass (already pre-treated for the extraction of hydrocolloids) in a concentration of 20 to 40 g / L- and / or mineral rich by-products from hydrocolloid activation in a concentration of 5 to 20 g / L, supplemented with a low 5 to 15 g / L concentration of glutamic acid precursor or other glutamic acid rich substrates (waste streams from monosodium glutamate production). Then, the initial biomass can be further pre-treated by means of high shear mixing, enzymatic or chemical hydrolysis to allow for higher amounts of sugars / amino acids to be released within the fermentation media. Optionally, the concentration of MnS04and NaCI can be altered to control the chemical properties of the biopolymer. Further the cell biomass (which produces the polymer) can be used as a compatibilizer for extrusion processes. As a result PHA is produced.

[0061] In an embodiment, the biowaste substrate comprised of post hydrocolloid extracted biomass (already pre-treated for the extraction of hydrocolloids) in a concentration of 20 to 40 g / L and / or mineral rich by-products from hydrocolloid activation -20 to 40 g / L, supplemented with low concentration of glucose 5 to 15 g / L or other simple sugars. The initial biomass can be extracted or waste organic biomass, and can be further pre-treated by means of high shear mixing, enzymatic or chemical hydrolysis to allow for higher amounts of sugars / amino acids to be released within the fermentation media. Optionally, the use of hydrocolloid activation by-products allow for biosynthesis of bacterial cellulose at the same rate as high sugar standard media (30 g / L sugar and amino acid rich peptone). Further the resulting biopolymer can be used in its entirety (without need for cell removal) or it can be removed by means of mild solventless treatment (boiling in tap water).

[0062] In an embodiment, for poly(hydroxyalkanoates) production, seaweed by-products are not employed as a primary carbon source but rather as an emulsifying agent for oils (virgin and spent rapeseed oil) including, but not limited to motor oils, vegetable oils, animal fats, waste cooking oil, algal oil, used lubricating oil, waste oils from industrial processes. It will be appreciated that a formulation of 5-15 wt% seaweed by-products is prepared and the PHA rich cell pellet is re-suspended in the solution with subsequent re-concentration of the pellet. The washing solution is then re-deployed for initial emulsification of the media with each of the different oils. Further the un-extracted biomass is used for extrusion purposes having the biomass as a compatibilizer between the hydrophilic seaweed hydrocolloid fraction and the hydrophobic PHA fraction. Beneficially, green extraction techniques (such as soap based or enzymatic techniques) are implemented for the isolation of the PHA.

[0063] The present disclosure also relates to the system for producing a biopolymer as described above. Various embodiments and variants disclosed above, with respect to the aforementioned biopolymer, apply mutatis mutandis to the system for producing a biopolymer. The term "fermenter" as used herein refers to a vessel or a bioreactor used for the production of various substances through fermentation. Notably, the fermenter provides a controlled environment for the growth and metabolism of microorganisms or cells, allowing them to convert raw materials into desired products. Typically, the fermenter consists of a container with appropriate controls for temperature, pH, agitation, and aeration.

[0064] The term "inoculum" refers to a small amount of the biowaste substrate that contains the desired microorganisms or cells, which serve as the starting culture for the fermentation process. In this regard, the system for producing the biopolymer includes the fermenter that is configured to facilitate the growth of the inoculum of the biowaste substrate.

[0065] The system functions by introducing the biowaste substrate and the supplementary substrate into the fermenter. The fermenter provides the necessary conditions, such as controlled temperature, pH, and nutrient availability, for the microorganisms or cells to grow and convert the biowaste substrates into the biopolymer.

[0066] It will be appreciated that the system with the fermenter offers improved process control, higher productivity, and better quality control, making it a valuable tool in the production of the biopolymer.

[0067] Optionally, the fermenter is further configured to grow the cellular biomass therein. In this regard, the fermenter is designed and adapted to support the growth of the cellular biomass, allowing the cellular biomass to multiply and metabolise the biowaste substrate and the supplementary substrate present in the system. Optionally, by providing a suitable environment with controlled conditions, such as temperature, pH, and nutrient availability, the fermenter promotes the proliferation of the cellular biomass.

[0068] Optionally, the fermenter is configured for solid-state fermentation or submerged fermentation under at least one of: an aerobic mode or an anaerobic mode. The term "solid-state fermentation" as used herein refers to a process where the fermentation takes place on solid substrates with limited or no free-flowing liquid. In this regard, the substrate and microorganisms are mixed together to form a solid-state matrix, and the fermentation occurs within the matrix. The term "submerged fermentation" as used herein refers to a process that involves the fermentation of a liquid substrate with the microorganisms or cells submerged in the liquid medium. The submerged fermentation allows for better mixing and oxygen availability for the microorganisms.

[0069] Furthermore, optionally, the fermentation can be conducted under either the aerobic or the anaerobic conditions, depending on the oxygen requirements of the microorganisms or the desired metabolic pathway.

[0070] Optionally, the system further comprises a kit of parts for pre-treating the biowaste substrate for generating post-treatment a hydrocolloid-extracted biowaste substrate, and isolation of biopolymer from the supplementary substrate. In this regard, the kit of parts may include various components and equipment necessary for the pre-treatment process, such as crushers, extractors, filtration systems, or chemical agents. Advantageously, said components work together to remove or extract hydrocolloids from the biowaste substrate, resulting in a refined substrate suitable for further processing.

[0071] Optionally, the system facilitates the isolation of the biopolymer from the supplementary substrate. Optionally, the isolation process involves separating the biopolymer from the remaining components of the supplementary substrate, such as impurities or unreacted materials. Optionally, the system may include specific equipment or techniques for this purpose, such as filtration, precipitation, or chromatography methods.

[0072] The present disclosure also relates to the method for producing a biopolymer of aforementioned first aspect as described above. Various embodiments and variants disclosed above, with respect to the aforementioned biopolymer and the aforementioned system for producing a biopolymer, apply mutatis mutandis to the method for producing a biopolymer.

[0073] Optionally, the method further comprises subjecting the biowaste substrate to sterilisation at a predefined temperature for a predefined period of time, wherein the sterilisation includes any of: a boiling or a heating of the biowaste substrate.

[0074] Optionally, the biopolymer is selected from at least one of: poly(gamma glutamic acid), bacterial cellulose and poly(hydroxyalkanoates), or derivatives thereof.

[0075] Optionally, the fermentation is a solid-state fermentation or submerged fermentation under at least one of: an aerobic mode or an anaerobic mode.

[0076] Optionally, the step of preparing the biowaste substrate comprises: procuring the biowaste substrate in the form of substrate flakes or absorbent biowaste substrate; and procuring a hydrocolloid-extracted biowaste substrate from hydrocolloid activation of the procured biowaste substrate.

[0077] Optionally, the method comprises pre-treating the biomass substrate by means of high shear mixing, mechanical methods, or enzymatic or chemical hydrolysis. In this regard, the high shear mixing allows for the breakdown of the biomass into smaller particles, increasing its surface area and facilitating better interaction with enzymes or chemicals during the subsequent steps. Optionally, the mechanical methods, such as grinding or milling, can physically disrupt the biomass structure, breaking it down into smaller fragments. Optionally, the pre-treatment through mechanical methods aids in the release of intracellular components and improves the overall efficiency of subsequent processing steps.

[0078] Optionally, the enzymatic hydrolysis involves the use of enzymes to catalyse the breakdown of complex biomolecules, such as carbohydrates or proteins, into smaller units. Thus, leading to higher yields and improved biopolymer production. Optionally, the chemical hydrolysis involves the use of chemicals, such as acids or alkalis, to break down the biomass into its constituent components. Thus, leading to improved biopolymer production yields and quality.

[0079] Optionally, the method comprises pre-treating a whole algae biomass by means of high shear mixing, mechanical methods, or enzymatic or chemical hydrolysis.

[0080] Optionally, the method comprises isolating the biopolymer using any of: a membrane filtration, tangential flow filtration, divalent cations / ethanol precipitation method, boiling in water, boiling in 1-5 wt% NaOH solution, and washing with a solution of 5 wt% waste substrate, soaps, and enzymes. Optionally, the method may utilise a porous membrane that acts as a selective barrier to separate impurities, such as particulate matter or larger molecules, from the biopolymer solution. Optionally, the biopolymer solution is passed tangentially across a membrane surface, creating a cross-flow that helps in continuous separation and removal of impurities.

[0081] Optionally, the divalent cations / ethanol precipitation method involves the addition of divalent cations (such as calcium or magnesium ions) or ethanol to the biopolymer solution. The addition of said agents causes the biopolymer to precipitate, separating it from the surrounding solution and facilitating its isolation.

[0082] Optionally, boiling the biopolymer solution in water allows the removal of heat-labile impurities or certain contaminants that are sensitive to high temperatures. Optionally, boiling the biopolymer solution in a sodium hydroxide (NaOH) solution can effectively eliminate biological contaminants, such as bacteria or fungi. Optionally, the method enables the purification of the biopolymer by washing it with a solution of 5 wt% waste substrate, soaps, and enzymes. Optionally, the waste substrate aids in removing residual impurities, whilst soaps and enzymes assist in solubilizing or breaking down specific contaminants, improving the purity and quality of the biopolymer.

[0083] Optionally, the method comprises subjecting the biopolymer to at least one of: drying and lyophilization. In this regard, the drying involves the removal of moisture from the biopolymer, resulting in a dry and solid product. Optionally, the drying is typically achieved by applying heat or airflow to the biopolymer solution, causing the water to evaporate. The technical effect of drying is the reduction of moisture content, which enhances the stability, shelf life, and handling characteristics of the biopolymer.

[0084] Optionally, lyophilization, also known as freeze-drying, is a more advanced drying technique that involves freezing the biopolymer under a vacuum and then sublimating the frozen water directly from ice to vapour, bypassing the liquid phase. Optionally, said process preserves the structure and properties of the biopolymer whilst removing moisture.

[0085] Optionally, the method comprises subjecting the biopolymer to a downstream processing and / or purification step. Herein, the downstream processing and / or purification step refer to degrees of purification to obtain different semi-processed products with beneficial properties for specific sectors. Beneficially, by employing the biowaste specifically from seaweed, namely, the seaweed by-product or the seaweed biowaste, the production of the three aforementioned biopolymers, namely poly(gamma glutamic acid) (100), bacterial cellulose (200), and poly(hydroxyalkanoates), with comparable or better characteristics than those produced from standard or conventional media, as well as products that are based on the three biopolymers, namely the derivatives of the aforementioned three biopolymers, having some of the components of the seaweed waste fraction, can be produced.

[0086] In an example, a crude purification step provides a derivative of a biopolymer (or a combination thereof with other one or two biopolymers) having great UV protection, and thus finds application in cosmetics sector as a moisturising product or ingredient. In another example, a high purification step provides a derivative of a biopolymer (or a combination thereof with other one or two biopolymers) having higher degree of carboxylic acid groups which better interacts with materials for wastewater treatment and thus finds application in the flocculation sector.

[0087] Optionally, the method comprises subjecting the biopolymer to a post-processing step selected from at least one of: an extrusion process, three-dimensional printing process, moulding process, packaging process, for different applications thereof. The term "extrusion" as used herein refers to a process that involves forcing the biopolymer through a die under controlled temperature and pressure conditions to create continuous shapes, such as films, fibres, filaments, sheets or tubes. The technical effect of subjecting the biopolymer to extrusion is to produce the biopolymer with controlled dimensions, uniformity, and specific properties. The term "three-dimensional (3D) printing" as used herein refers to the creation of complex three-dimensional objects layer by layer. The technical effect of 3D printing is the ability to fabricate biopolymer products with intricate designs, tailored functionalities, and the potential for rapid prototyping in various fields, including medicine, engineering, and consumer goods. The term "moulding" refers to a process that involves shaping the biopolymer by pouring it into a mould and allowing it to solidify. Optionally, the moulding process can be performed by injection moulding, compression moulding, or other moulding techniques. Optionally, the biopolymer may be subjected to a packaging process that involves the containment and protection of the biopolymer in suitable materials for storage, transport, and presentation. Optionally, the packaging processes may include sealing, wrapping, or enclosing the biopolymer in films, containers, or other packaging materials. The technical effect of the packaging process is the preservation of the biopolymer's quality, integrity, and stability, ensuring its suitability for various commercial and consumer applications.

[0088] DETAILED DESCRIPTION OF THE DRAWINGS

[0089] Referring to FIG. 1, illustrated is the process of biosynthesising poly(gamma glutamic acid) 100, in accordance with an embodiment of the present disclosure. A biowaste substrate 102, such as a plurality of waste red seaweed fractions, is shown. The plurality of waste red seaweed fractions is provided to the mixing equipment 104. Herein, the mixing equipment can be a mortar and pestle, a ball mill grinder or a high shear mixer. At point A, a supplementary substrate such as a sucrose solution having a concentration of 25 g / l and L-glutamic acid having a concentration of 10 g / l is added to the plurality of waste red seaweed fractions to form a mixture. The mixture is then fed into a fermenter 106 having an agitator 108 that is operable for agitating the mixture at a speed of 100 rpm to 1000 rpm to maintain the dissolved oxygen above 30% therein. Herein, the fermenter may have a volume of 4000 mL. The starter culture is then prepared in a fermentation broth inside the fermenter 106 and inoculated in a growth medium, for example, TSB and incubated, for example at 37° C for 24 h. At point B, the biomass is separated from a supernatant. At point C, the material in the supernatant is isolated. At point D, a raw precipitate 108 is obtained after performing the drying process. At point E, the dry precipitate is re-solubilised in a deionized water. At point F, a purification process is implemented to obtain the poly(gamma glutamic acid) 100 in a dry purified precipitate form.

[0090] Referring to FIG. 2, illustrated is a process of biosynthesising bacterial cellulose 202, in accordance with an embodiment of the present disclosure. A biowaste substrate 204 is shown. At point A, the biowaste substrate 204 is provided to the mixing equipment 206. Herein, the mixing equipment 206 can be a mortar and pestle, a ball mill grinder or a high shear mixer. At point B, the biowaste substrate 204 comprising an algal flakes waste substrate and a perlite based waste substrate is prepared. The algal flakes waste substrate comprises an algal fraction in a concentration of 40 g / L and glucose or other simple sugars in a concentration of 30 g / L. The perlite based waste substrate comprises an algal fraction in a concentration of 40 g / L and glucose or other simple sugars in a concentration of 30 g / L. Notably, various ratios (such as from 50:50 to 15:85 and 85: 15) of algal flakes to perlite based waste substrate can be employed to tailor the final chemical and physical properties of the biopolymer material. The pH of the biowaste substrate 204 is adjusted to 5.5 and the biowaste substrate 204 is autoclaved at a temperature of 115 °C, and a pressure of 2 bar for a time period of 20 minutes. A fermenter 208 is shown having a volume of 20 L, with pH regulation at 5.5 (through 2M NaOH and 2M HCI stock solutions). The fermenter 208 is fed with a starter culture, comprising 5-30 wt% (e.g., 10 wt%) of the bacterial cellulose for seeding. The fermentation temperature ranges from 25 to 45 °C, preferably 30 °C. At point C, the starter culture is fermented for a fermentation time period of 5 days to 3 weeks, affecting the final properties of the bacterial cellulose, such as thickness (ranging from 0.3 cm to 2 cm when hydrated). At point D, the fermentation media, Gluconoacetobacter xylanus inoculum, and the bacterial cellulose are added together in a flask. At this point, the formed material produced at the surface of the flask is collected and placed in a distilled water solution containing 2 wt%

[0091] NaOH. The solution is then heated at 50 °C or above for 1 to 20 hours

[0092] (depending on the thickness of the material). At point E, the material is then submerged in the distilled water solution to rebalance the pH. At point F, the material is hydrated and then at point G, the material is dried from excessive water and is lyophilised to obtain the bacterial cellulose 202.

[0093] Referring to FIG. 3, illustrated is a process of biosynthesising a Poly(hydroxyalkanoate) 300, in accordance with an embodiment of the present disclosure. A biowaste substrate 304 is shown comprising an algal flakes waste substrate and a perlite based waste substrate. The algal flakes waste substrate comprises an algal fraction in a concentration of 40 g / L and waste oil fraction in a concentration of 36 g / L. The perlite based waste substrate comprises algal fraction in a concentration of 40 g / L and waste oil fraction in a concentration of 36 g / L. Notably, various ratios (such as from 50:50 to 15:85 and 85: 15) of algal flakes to waste substrate can be employed to tailor the final chemical and physical properties of the biopolymer material. The pH of the biowaste substrate 304 is adjusted to 6.8 and the biowaste substrate 304 is autoclaved at a temperature of 115 °C, a pressure of 2 bar for a time period of 20 minutes. At point A, the biowaste substrate 304 is provided to the mixing equipment 306. Herein, the mixing equipment 306 can be a mortar and pestle, a ball mill grinder or a high shear mixer. As shown, 1 colony of Ralstonia eutropha is aseptically added to a 250 mL of sterile tryptic soy broth. A fermenter 308 is shown. The fermenter 308 has a volume of 7 L with a pH regulation of 6.8 (through 2M NaOH and 2M HCI stock solutions). Moreover, a 10 wt% of starter is added to the fermenter 308 to seed. Furthermore, the fermentation temperature can be in a range from 25 °C to 45 °C, preferably 37 °C. The fermentation time can be in a range from 24 to 116 hours, with the optimal being 72 hours. At point B, the biomass is separated from the supernatant. At point C, a PHA rich biomass is obtained. At point D, the PHA is extracted with chloroform (as a solvent), soaps or enzymes. At point E, the PHA 300 is obtained.

[0094] Referring to FIG. 4, illustrated is a flowchart of a method for producing a biopolymer, in accordance with an embodiment of the present disclosure. At step 402, a biowaste substrate comprising at least one of: a cellular biomass and an acellular material is prepared. At step 404, the biowaste substrate is added to a supplementary substrate in a fermenter. At step 406, the biowaste substrate is grown in the supplementary substrate under optimal process conditions. At step 408, the biopolymer is isolated from the supplementary substrate.

[0095] The aforementioned steps are only illustrative and other alternatives can also be provided where one or more steps are added, one or more steps are removed, or one or more steps are provided in a different sequence without departing from the scope of the claims herein.

Claims

CLAIMS1. A biopolymer synthesised from a biowaste substrate (102, 204, 304) comprising at least one of: a cellular biomass and an acellular material; and a supplementary substrate, wherein, when grown under optimal process conditions, the yield and physicochemical properties of the biopolymer are regulated by concentrations of the biowaste substrate, the supplementary substrate and the process conditions.

2. A biopolymer according to claim 1, wherein the cellular biomass of the biowaste substrate (102, 204, 304) is selected from a bacterium or an algae, preferably, seaweed by-product.

3. A biopolymer according to claim 2, wherein the bacterium is selected from at least one of: genus Bacillus, genus Gluconoacetobacter , genus Ralston la.

4. A biopolymer according to claim 2, wherein the algae is a macroalgae selected from Agarophytes, Carraghenophytes, Rhodophytes, Chiorophytes, Prasinodermophyta and Phaeophyceae.

5. A biopolymer according to any of preceding claims, wherein the biowaste substrate (102, 204, 304) is a hydrocolloid-extracted biowaste substrate.

6. A biopolymer according to any of preceding claims, wherein the supplementary substrate is rich source of at least one of: sucrose, simple sugars, L-glutamic acid, glucose, waste oil, perlite waste from the extraction of hydrocolloids, metals ions selected from sodium ion, manganese ion, magnesium ion, zinc ion, and iron ion, and monosodium glutamate.

7. A biopolymer according to any of preceding claims, wherein the supplementary substrate is obtained from a pure source or an industrial waste source.

8. A biopolymer is produced according to claim 1 or 2, wherein the biopolymer is selected from at least one of: poly(gamma glutamic acid) (100), bacterial cellulose (200), and poly(hydroxyalkanoates) (300), or derivatives thereof.

9. A biopolymer according to any of preceding claims, wherein the optimal process condition comprises: a pH of 4-7; a fermentation temperature of 25-37 °C; a fermentation time period of 1-21 days; and a dissolved oxygen concentration above 30%.

10. A biopolymer according to any of preceding claims, wherein the optimal process condition further comprises: an agitation of 100 to 1000 rpm for production of poly(gamma glutamic acid) (100) and poly(hydroxyalkanoates), or a static condition for production of bacterial cellulose.

11. A biopolymer according to any of preceding claim, wherein the biowaste substrate (102, 204, 304) is subjected to sterilisation at a predefined temperature for a predefined period of time, wherein the sterilisation includes any of: boiling, heating, or irradiation of the biowaste substrate, or the addition of a sterilisation agent to the biowaste substrate.

12. A biopolymer according to claim 11, wherein the biowaste substrate (102, 204, 304) is subjected to heating in the form of autoclaving at an autoclaving temperature of 100-130 °C, preferably 115 °C, under a pressure of 0-3 bar, preferably 2 bar, for a time period of 1-60 minutes, preferably 20 minutes.

13. A system for producing a biopolymer comprises a fermenter (106, 208, 308) configured to grow an inoculum of biowaste substrate (102, 204, 304) with the supplementary substrate to produce the biopolymer.

14. A system according to claim 13, wherein the fermenter (106, 208, 308) is further configured to grow the cellular biomass therein.

15. A system according to claim 13 or 14, wherein the fermenter (106, 208, 308) is configured for solid-state fermentation or submerged fermentation under at least one of: aerobic mode or anaerobic mode.

16. A system according to claims 13 to 15, further comprising a kit of parts for pre-treating the biowaste substrate (102, 204, 304) for generating post-treatment a hydrocolloid-extracted biowaste substrate, and isolation of biopolymer from the supplementary substrate.

17. A method for producing a biopolymer of claim 1-12, the method comprising: preparing a biowaste substrate (102, 204, 304) comprising at least one of: a cellular biomass and an acellular material; adding the biowaste substrate to a supplementary substrate in a fermenter (106, 208, 308); growing the biowaste substrate in the supplementary substrate under optimal process conditions; and isolating the biopolymer from the supplementary substrate.

18. A method according to claim 17, further comprising subjecting the biowaste substrate (102, 204, 304) to sterilisation at a predefined temperature for a predefined period of time, wherein the sterilisation includes any of: a boiling or a heating of the biowaste substrate.

19. A method according to claim 17 or 18, wherein the biopolymer is selected from at least one of: poly(gamma glutamic acid) (100), bacterial cellulose and poly(hydroxyalkanoates), or derivatives thereof.

20. A method according to claim 17 to 19, wherein the fermentation is a solid-state fermentation or submerged fermentation under at least one of: aerobic mode or anaerobic mode.

21. A method according to claims 17 to 20, wherein the step of preparing the biowaste substrate (102, 204, 304) comprises: procuring the biowaste substrate in the form of substrate flakes or absorbent biowaste substrate; and procuring a hydrocolloid-extracted biowaste substrate from hydrocolloid activation of the procured biowaste substrate.

22. A method according to claims 17 to 21, wherein the method comprises pre-treating the biomass substrate by means of high shear mixing, mechanical methods, or enzymatic or chemical hydrolysis.

23. A method according to claims 17 to 21, wherein the method comprises pre-treating a whole algae biomass by means of high shear mixing, mechanical methods, or enzymatic or chemical hydrolysis.

24. A method according to claims 17 to 23, wherein the method comprises isolating the biopolymer using any of: membrane filtration, tangential flow filtration, divalent cations / ethanol precipitation method, boiling in water, boiling in 1-5 wt% NaOH solution, and washing with a solution of 5 wt% waste substrate, soaps and enzymes.

25. A method according to claims 17 to 24, wherein the method comprises subjecting the biopolymer to at least one of: drying and lyophilization.

26. A method according to claims 17 to 25, wherein the method comprises subjecting the biopolymer to a post-processing step selected from at least one of: an extrusion process, three-dimensional printing process, moulding process, packaging process, for different applications thereof.

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