Production process of bacterial cellulose sheets as an alternative to leather using environmentally friendly agricultural waste

Abstract

This invention is a process for producing bacterial cellulose sheets as an alternative to leather. The production process according to this invention is inexpensive, easy, more environmentally friendly by not using specific commercial media for starter propagation and bacterial cellulose growth and not using expensive and non-environmentally friendly non-natural chemicals to optimize the production process but instead using agricultural waste and natural materials. The present invention uses control of sugar and pH values to optimize the production process, low energy consumption and can be used for large production scales. This invention consists of: preparing microbial starter propagation media, preparing microbial starter stock, performing agricultural waste extraction, controlling the Brix value of the extracted results, preparing bacterial cellulose growth media, growing bacterial cellulose sheets, harvesting bacterial cellulose sheets, cleaning harvested cellulose sheets, performing initial-drying, improve the quality of bacterial cellulose sheets, performing final-drying of bacterial cellulose sheets, coating a cotton-based fabric onto dry bacterial cellulose sheet and providing a water-repellent coating on the surface of dry cellulose sheet.

Description

[0001] Description

[0002] PRODUCTION PROCESS OF BACTERIAL CELLULOSE SHEETS AS AN ALTERNATIVE TO LEATHER USING ENVIRONMENTALLY FRIENDLY AGRICULTURAL WASTE

[0003] Technical Field

[0004] The present invention relates to a process for producing bacterial cellulose sheets as an alternative to leather . More speci fically, this invention uses agricultural waste as a source of sugar for microbial starter propagation and for conversion to cellulose by a combination of bacteria and fungi and without using nonnatural chemicals to optimi ze the production process .

[0005] Background Art

[0006] The leather industry is a continuously growing industry, but leather production is a process that is not environmentally friendly, one of which is the leather tanning process which uses a variety of hazardous chemical compounds , namely chromium . Chromium compounds can be toxic in nature and are harmful to animal and human health when exposed . One of several products that are used as a solution to this matter is synthetic leather, but synthetic leather is commonly made from polyvinyl chloride ( PVC ) and polyurethane ( PU) , two compounds that are di f ficult to degrade . Thus , it is required to find an environmentally friendly solution that can be an alternative to leather .

[0007] Cellulose is the most abundant carbohydrate polymer in the world and generally can be extracted from plants and plant residues . But cellulose obtained through plants usually must be processed first using hazardous chemicals , so it tends to be unfriendly to the environment . It is known that there are several types of bacteria that are able produce cellulose . The cellulose produced by these bacteria is commonly known as bacterial cellulose . Bacterial cellulose has several advantages , namely a higher water holding capacity when compared to plant cellulose , high mechanical strength, and a high degree of polymeri zation .

[0008] Bacterial cellulose can be used in several industries , including the food industry, leather industry, textile , paper, and packaging industries . Its environmentally friendly property causes bacterial cellulose material to be an alternative in creating environmentally friendly products .

[0009] As to date , bacterial cellulose is more widely used in the medical field, namely as a wound dressing, material for tissue engineering, and arti ficial blood vessels . The expansion of the use of microbial cellulose in other products is still very limited due to high production costs . Commonly, Hestrin Schramm (HS ) medium is used to produce microbial cellulose for the formation of relatively expensive bacterial cellulose .

[0010] Bacterial cellulose has a fairly short production time , and can be produced using a variety of nutrient sources for cellulose-producing bacteria . In the previous arts , the methods of culturing cellulose-producing bacteria and producing cellulose generally used expensive commercial Hestrin Schram (HS ) medium or sel f-made media containing sugar solution or natural sugar-contained materials such as fruit extracts , vegetable extracts , tea extracts , tubers , coconut water, coconut milk and others , but commonly mixed with chemicals to optimi ze cellulose production .

[0011] Bacterial cellulose can be produced from bacterial species that are able to produce cellulose such as Achromobacter, Al caligenes , Aerobacter, Agrobacteri um, Azotobacter, Gl uconacetobacter, Pseudomonas , Rhi zobi um, Sarcina , Di ckeya , and Rhodobacter . However, the most commonly used bacteria come from the genus of Komoiga taeibacter, which was previously called Gl ucanacetobacter . Bacteria from this genus are used because they have the ability to convert various types of carbon and nitrogen . The cellulose-producing bacteria can convert several types of carbon sources such as glucose , xylose , mannose , arabinose , galactose , sucrose , and maltose into bacterial cellulose sheets .

[0012] As to date , there have been patents on methods for producing bacterial cellulose , such as patent No . CN101671708A regarding methods for producing microbial cellulose using pineapple peels . This patent still uses additional non-natural chemical compounds for optimi zing bacterial growth and cellulose growth and therefore production costs tend to be high and not environmentally friendly . The productivity of production using the method according to thi s patent is 17 . 5 grams / liter, which is a small value when compared to the present invention . In addition, the said patent requires stirring to propagate starter bacteria and therefore the process becomes expensive and requires additional apparatus . In addition, the said patent is only limited to the method of microbial cellulose production and does not reach the stage of producing microbial cellulose products that are ready to be used as an alternative to leather with the same scope of use . US Patent US 8541001B2 entitled "Bacterial Cellulose Based ' Green ' Composites" , relates to the production of a composition consisting of bacterial cellulose and soybased resin reinforced with high strength bacterial cellulose . The invention in this patent uses grain extract as a medium for the production of bacterial cellulose . This method is limited to a few types of grains , namely soybeans , wheat , corn, or other types of legumes . This patent is not yet ef ficient to be carried out on a large scale where starter production still uses expensive commercial media . In addition, media processing for the bacterial cellulose production uses hazardous chemicals , namely HC1 , thereby reducing the value of environmental friendliness .

[0013] Patent No . CN102703543B regarding a method for producing bacterial cellulose using tubers as a basic ingredient for growth media for cellulose-producing bacteria . This patent has the advantage that the use of tubers as growth material can reduce production costs , but this patent does not have the steps to propagate and regenerate bacterial cellulose cultures yet which are very important for escalating production . The method in this patent also uses enzymes for tuber hydrolysis , uses non-natural chemical compounds to adj ust the pH and uses stirring which requires a lot of energy .

[0014] Patent No . KR102192110 regarding a product and method for manufacturing bacterial cellulose-based biological leather modi fied with the addition of soy protein fractions and compounds containing hydroxyl to increase the durability and flexibility of cellulose sheets ; the invention in this patent does not disclose the starter propagation process and still uses a commercial medium, namely HS in the manufacturing example for growing bacterial cellulose and uses soy protein as an ingredient . Therefore , the products produced using the method according to this patent are still expensive and not environmentally friendly .

[0015] Patent No . EP3715110 with the title of "Leather Alternative Material" discloses material product as an alternative to leather and production method thereof . The material product according to the patent is based on bacterial cellulose which is given a reinforcing layer in the form of bioplastic . In the stage of forming bacterial cellulose , the invention of the patent uses green or black tea as a nitrogen source and sugar as a carbon source for bacteria . In addition, the cleaning and refining processes still use non-natural chemicals in the form of acetic acid, which makes the production method high-cost , inflexible in the use of raw materials and less environmentally friendly .

[0016] Another patent No . WO2022177529A1 is titled "A Bioleather Production Method" , which discloses a production method of leather produced from bacteria or bioleather that is similar to leather . This invention uses limited sources of sugar, namely extracts of green tea and black tea . The microbes used are a combination of cellulose-producing bacteria and yeast that is able to break down sugar to accelerate the performance of bacteria . And this invention uses another additional fungus , namely lichen as the main source of carbon and nitrogen, and there is a chemical of acetic acid as well . Therefore , the raw materials of the process become limited, and the process is expensive and less environmentally friendly .

[0017] From the existing problems and weaknesses of the comparison patents mentioned above , the bacterial cellulose process according to the present invention uses control of pH and Brix values to optimi ze the quality of the process , so that all sugar-contained agricultural waste can be used to produce bacterial cellulose . In addition, this invention uses environmentally friendly materials in the process so that the production becomes easier, cheaper and environmentally friendly .

[0018] Summary of Invention

[0019] The main obj ective of the present invention is to provide a process for the production of bacterial cellulose that is inexpensive , easy, more environmentally friendly and usable on a large scale . This can be carried out as the present invention does not use speci fic commercial media for starter propagation and formation of bacterial cellulose sheets but instead uses agricultural waste , does not use chemicals to optimi ze the production of bacterial cellulose sheets , uses simple apparatus that is easy to obtain and does not consume a lot of energy, and its productivity can be escalated as it can be carried out continuously by utili zing the leftover microbial starter stock . The production process according to the present invention consists of : preparing a microbial starter propagation medium solution; preparing microbial starter stock, extracting agricultural waste , controlling the Brix value of the extracted liquid, preparing bacterial cellulose growth media, growing bacterial cellulose sheets , harvesting bacterial cellulose sheets that have been formed, cleaning harvested cellulose sheets , initial-drying bacterial cellulose sheets , performing staining, increasing flexibility and deodori zing the initial-dried bacterial cellulose sheets , performing final-drying on bacterial cellulose sheets , coating cotton-based fabrics onto the final-dried bacterial cellulose sheets and providing a water-repellent coating to the surface of the dried cellulose sheets .

[0020] Brief Description of Drawings

[0021] In order for the present invention to be fully explained, this invention will be described in detail with reference to the accompanying drawings , wherein :

[0022] Figure 1 shows a flow chart of the process for the production of bacterial cellulose sheets according to the present invention .

[0023] Figure 2 shows an illustration of a container for growing bacterial cellulose sheets .

[0024] Description of Embodiments

[0025] The present invention relates to a process for producing bacterial cellulose sheets as an alternative to leather . This invention uses agricultural waste as a source of sugar to be converted by bacteria into cellulose . This invention does not use commercial materials and non-natural chemical compounds either as raw materials or processing aids or for controlling or for optimi zing the production process but instead uses agricultural wastes for the propagation of microbial starter and the formation of bacterial cellulose sheets and does not use commercial materials or non-natural chemicals as raw materials , auxiliary materials or production process controllers . In addition, this invention uses simple methods and apparatus that are easy to obtain and do not consume a lot of energy . The present invention leaves a stock of prepared microbial starter to be propagated and made a new stock of microbial starter by a subsequent production process . Therefore , the production process becomes continuous and fast . Thus , the production process of bacterial cellulose sheets according to this invention becomes a process that is easy, inexpensive , more environmentally friendly and the production capacity can be escalated on a four-quarters scale .

[0026] As shown in Figure 1 which shows a complete f low chart of the process for producing bacterial cellulose sheets according to the present invention, this invention consists of the following steps : preparing the microbial starter propagation medium solution; preparing microbial starter stock; extracting nutrients from agricultural waste ; controlling the Brix value of liquid of nutrients extracted from agricultural waste ; preparing bacterial cellulose growth media ; distributing bacterial cellulose growth media to bacterial cellulose growth containers ; growing bacterial cellulose sheets in bacterial cellulose growth containers ; harvesting the formed bacterial cellulose sheets ; cleaning the harvested cellulose sheets ; performing initial-drying of bacterial cellulose sheets ; performing staining, flexibility improvement and deodori zation on the initial-dried bacterial cellulose sheets and performing final-drying on bacterial cellulose sheets to obtain the final product of cellulose sheets that are ready to be used as an alternative to leather . A detailed explanation of each of the steps above will be explained next .

[0027] In the early step of the production process according to this invention, preparation of a microbial starter propagation medium solution is carried out by mixing cof fee ( Coffea ) husks or cascara waste , table sugar and water into a solution . The mixed solution of these ingredients is controlled for the value of the sugar content or Brix between 7- 10 . After the cof fee husks , sugar and water are mixed and the Brix value is reached as mentioned above , then the solution is boiled until it boils or at a temperature of 100°C, which then the solution is cooled down to room temperature or 19- 40°C, so that a microbial starter propagation medium solution is obtained . The cof fee husks used at this step is 200-2000 g for every 1 L o f solution . Before the cof fee husks are mixed with sugar and water, the cof fee husks are sterili zed by boiling the cof fee husks separately in boiling water or 100°C, then the cof fee husks and boiling water are passed through a filter to separate the cof fee husks from impurities .

[0028] At the step of preparing microbial starter stock, the microbial starter is grown in a solution of microbial starter propagation media . The microbes used in this invention are a mixture of Komaga taeibacter xylinus bacteria and yeast in the form of the fungus Saccharomyces cerrevi cae . Komaga taeibacter xylinus is a cellulose bacterium that is able to convert sugar into cellulose . In the production process according to this invention, the source of sugar is agricultural waste . Meanwhile , Saccaromyces cerrevi cae is a fungus that functions to help break down sugar from agricultural waste so that it is easier for the bacteria of Komaga taeibacter xylinus to convert it into cellulose so that the process of growing bacterial cellulose sheets according to thi s invention becomes faster . Microbes are mixed with starter propagation media, with a volume ratio of 1 : 2-4 .

[0029] Mixing the microbes with the starter propagation media is carried out in a closed container that still has access to fresh air into the container and with the initial conditions of the propagation media pH value of 4- 6 and Brix value of 3- 10 . The container used for the microbial starter growth process can be in the form of a closed container which has an open area at the top of the container, which is then covered with a fabric which has fine holes so that fresh air can enter the container, but dust or other impurities from outside the container cannot enter into the container . And then, waiting for the growth of the microbial starter in the growth medium solution until the media pH value is 2 . 5-3 . 5 and the Brix value is 1 -4 . The condition of the pH and Brix values is achieved within 14 - 35 days . I f the pH and Brix values have been reached, the microbial starter stock i s ready for use . I f more than 35 days the conditions of pH and Brix values are not reached then the process of propagating the microbial starter for stock fails and must be repeated . I f the conditions for the pH and Brix values are achieved in less than 24 days , then the next step must be carried out more quickly .

[0030] At the step of extracting nutrients from agricultural waste containing sugar, i f the agricultural waste is in a fresh state then pressing is performed against the waste to obtain a liquid extract . I f the agricultural waste is dry or the water content is less than 10% , then the waste is mixed with water and boiled until it boils to obtain a liquid extract of the waste . The extracted liquid is separated from the solid by filtering the solid . Agricultural wastes used in this step are those containing sugar, such as cof fee husks ( Coffea ) , cocoa peels ( Theobroma cacao) , j engkol peels ( Archi dendron paucifl orum) , cassava peels (Manihot escul enta ) , Cilembu sweet potato peels ( Ipomoea ba ta tas) , pineapple peels ( Ananas comosus) and tomato peels ( Solanum lycopersi cum) .

[0031] After obtaining the liquid extract of agricultural waste , the sugar content value or the Brix value of the liquid extract of agricultural waste is controlled between 7- 10 . I f the Brix value is less , table sugar or liquid agricultural waste containing high sugar is added, then stirred until dissolved . Agricultural waste liquids that can be used to increase the Brix value are liquid molasses and liquid sorghum . Meanwhile , i f the Brix value is excessive , then water is added . Thus the Brix value of the liquid extract of agricultural waste can be maintained at 3- 10 .

[0032] The next step after obtaining the liquid extract of agricultural waste is the step of preparing bacterial cellulose sheet growth media, which are the media used by microbes to convert the liquid extract of agricultural waste into cellulose in the form of sheets according to the growth container . At this step, the liquid extract of agricultural waste is boiled until it boils or at a temperature of 100°C, then it is cooled to a room temperature of 25°C - 35°C and filtering impurities from the liquid, so that a cellulose sheet growth medium is obtained .

[0033] After obtaining the cellulose sheet growth media, the bacterial cellulose growth media is distributed to the cellulose sheet growth containers , namely the containers where the process of growth and formation of cellulose sheets occurs . The distribution of the cellulose sheet growth media is carried out by pouring the cellulose sheet growth media into the cellulose sheet growth containers until they fill the containers . Growth containers generally have a shape adapted to the desired shape of the final cellulose sheet . As shown in Figure 2 , for ease of production, storage and utili zation of the product , the proper shape of the container is rectangular or square , to form the final cellulose sheet that follows the rectangular or square sheet- shaped container and has a certain thickness . In order for the formation of cellulose sheets on the cellulose sheet growth media in the cellulose sheet growth containers to occur more quickly, the surface area of the containers in the form of trays , which is the multiplication of the length ( L ) and the width (W) of the container, must be much larger than the height (H) . This is carried out so that the ratio of the surface area to the height of the bacterial cellulose growth media placed in these containers will also have a surface area value that is far greater than the height , with a ratio of 10-20 : 1 . For example , i f the surface area of the bacterial cellulose growth medium in the growth container is between 100 cm2, then the height of the growth medium in the container is 5 - 10 cm . To increase production capacity and space ef ficiency, these containers or trays can be arranged in layers on shelves . The containers used can be made of metal or plastic .

[0034] The next step after the cellulose sheet growth media is distributed to the cellulose sheet growth containers is the step of growing bacterial cellulose sheets in the bacterial cellulose growth containers . This step is carried out by mixing the microbial starter stock that has been prepared into the bacterial cellulose sheet growth media that have been placed in cellulose growth containers . Microbial starter is added to the bacterial cellulose sheet growth medium at a ratio of 1 : 4 v / v and added until the pH reached a value of 3 . 5- 6 . Lowering the pH to become acidic is necessary to prevent contamination from other microbes . Next , the microbial starter mixture and bacterial cellulose sheet growth media in the growth container are left in static conditions until bacterial cellulose sheets are formed . At the step of mixing the microbial starter into the cellulose sheet growth media, the microbial starter used is a maximum of 50-75% of the volume of the starter stock prepared . This is so that the remaining 25-50% of the starter stock can be reproduced and used in the next step of bacterial cellulose production . Thus , the next production process becomes faster, because it can be continuous without waiting for new microbial starter propagation media to be prepared first . With the use of shelves to place cellulose growth containers and the production process can continue quickly, the production capacity becomes large . Therefore , the cellulose sheet production process according to the present invention can be used for large scale production . The productivity of production results using the method according to this invention for one production process can produce 40 grams / liter of bacterial cellulose .

[0035] The next step i s harvesting the formed bacterial cellulose sheets . These cellulose sheets are harvested while still wet , when the growth medium reaches a pH value of 3-4 and a Brix value of 3-5 . Generally biocellulose sheets are harvested when the thickness reaches 1- 1 . 5 cm, but i f the thickness has not reached 1- 1 . 5 cm, bacterial cellulose sheets must still be harvested, because it will slow down the growth process of further cellulose sheets and bacterial growth that is no longer optimal. The process of growing cellulose sheets until they can be harvested takes 2 - 4 weeks.

[0036] After the cellulose sheets are harvested, the bacterial cellulose sheets that have been harvested are cleaned from yeast films using water. Next, after cleaning the harvested cellulose sheets, the initial stage of drying is carried out. Initial-drying is carried out until the cellulose sheet reaches a moisture content of 5-20%. Drying can be done by drying in the sun or using a drying chamber if there is no sunlight and accelerating the production process is desired. If using a drying chamber, the drying chamber temperature is a maximum of 100°C. If the harvested cellulose sheets still contain deficiencies or defects, such as the thickness is less than 1-1.5 cm nor there are holes in the cellulose sheets, then before the initial-drying is carried out, the wet bacterial cellulose sheets are stacked one on top of the other so that they stick and a minimum thickness of 1-1.5 cm is achieved and the holes are covered by another sheet. The thickness of the harvested bacterial cellulose sheet is under 1 cm, it is usually crushed in pieces, does not form sheet, making stacking difficult.

[0037] The next step after drying the cellulose sheets in the early steps is improving the quality of the bacterial cellulose sheets which include staining, flexibility improvement and deodorization. Staining, flexibility improvement and deodorization are carried out by soaking the cellulose sheet in a solution containing a mixture of natural staining agents, natural ingredients that provide flexibility such as vegetable glycerol, and natural deodorizing ingredients such as citronella oil for 12-24 hours. The natural staining agents used in this invention include spurred mangrove wood (Ceriops tagal) , sappan wood ( Biancaea sappan) , tarum leaves ( Indi gofera ) , tageran wood ( Cudrania javanensi s) , teak leaves ( Tectona grand! s) , turmeric ( Curcuma l onga ) , su j 1 leaves ( Dracaena angusti folia ) or pandan leaves ( Pandanus amaryllifoli us) .

[0038] The next step is performing the final-drying of the bacterial cellulose sheets after being treated to improve quality . Final-drying is done so that the dry cellulose sheet has a moisture content of 5- 10% or a thickness of 0 . 4- 1 . 2 mm .

[0039] Then the coating or backing is carried out on the final-dried bacterial cellulose sheet , namely by adding one surface of the dry bacterial cellulose sheet using a cotton-based fabric to increase the tear resistance of the material or the dry bacterial cellulose sheet or the final-dried bacterial cellulose sheet by using an adhesive , which then the bacterial cellulose sheet and the coating fabric are both pressed at a temperature of 80- 100°C until the coating fabric adheres firmly to one surface of the bacterial cellulose sheet .

[0040] The last step is the application of a water- repellent coating to the final-dried bacterial cellulose sheet which has been given a fabric coating on one of its surfaces using water-repellent materials which can be in the form of resins , waxes , or polymers in the form of Polylactic Acid ( PLA) on the top of the cellulose sheet which is not covered with fabric . Coating of water- repellent materials which can be in the form of resins , waxes , or polymers in the form of Polylactic Acid ( PLA) on the surface of dry bacterial cellulose sheets can be through sweeping or by spraying onto the surface of the cellulose sheets to form a water-repellent layer (water proof ) on the surface of the dry bacterial cellulose .

[0041] The final product obtained from all the production steps previously described is in the form of dry cellulose sheet which already has a fabric coating on one surface and a coating with a water-repellent material on the other surface . Furthermore , the final product according to the invention is ready to be used as a substitute for leather which is ready for the tanning process and the manufacturing process to become various finished products . Table 1 shows a comparison of the physical properties of leather and bacterial cellulose produced from the process according to this invention, namely tear resistance and tensile strength . Bacterial cellulose without being coated with a cotton-based fabric which has a tear resistance of 7 N, can be increased to 60 N by being coated with a cotton-based fabric . As for the tensile strength properties of bacterial cellulose with or without upholstery, the values are relatively the same or not too di f ferent from leather .

[0042] Bacterial cellulose sheet resulting from the process according to this invention can be used as raw material for alternative to leather for end products that can be used by users such as curtains , shoes , bags , wallets , hats , etc . , as well as end products using leather as the main raw material .

[0043] Table 1 . Comparison of the Physical Properties of Leather with Bacterial Cellulose According to this Invention

Claims

Claims1 . A process for producing bacterial cellulose sheets as an alternative to leather, which uses agricultural waste as a medium for bacterial propagation and for conversion into cellulose sheets , which consists of the following steps : a . preparing microbial starter propagation media, by mixing cof fee husks , sugar and water, which is characteri zed by controlling the value of the sugar content or the Brix value of the medium solution of 7- 10 , then boiling the solution until it boils or at a temperature of 100°C, which then cooling it down to room temperature of 19°- 40°C ; b . preparing a microbial starter stock, by mixing the microbial starter in the form of a mixture of Komaga taeibacter xylinus bacteria and yeast in the form of the fungus Saccharomyces cerrevi cae with the microbial starter propagation media that has been made , which is characteri zed by a volume ratio of both of 1 : 2 -4 , which is mixed in a closed container that is still has access to fresh air into the container and with the initial conditions of the propagation media has a pH value of 4- 6 and Brix value of 3- 10 , and then waiting for the growth of the microbial starter in the propagation medium solution until the medium solution has a pH value of 2 . 5- 3 . 5 and a Brix value of 1-4 for 14 - 35 days ; c . performing the extraction on sugar-contained agricultural waste , which is characteri zed by pressing for fresh waste or boiling with water at a temperature of 100°C for dry waste with a moisture content below 10% , to obtain a liquid extract of the agricultural waste , which is then separated from the solid by filtering;d . controlling the Brix value of the liquid extracted from agricultural waste that has been obtained to be between 3- 10 , by adding sugar or waste liquid containing high sugar to the extracted liquid and then stirring it unti l dissolved i f the Brix value is less than 7 , or by adding water i f the Brix value is more than 10 ; e . preparing bacterial cellulose growth media, by boiling until boiling or at a temperature of 100°C the liquid extracted from agricultural waste products from step d, which then cooling it to a temperature of 25°C- 35°C, then filtering the impurities in the media with a filter ; f . growing bacterial cellulose sheets , by distributing the bacterial cellulose growth media to bacterial cellulose growth containers , then adding the prepared microbial starter stock to the bacterial cellulose sheet growth media, which is characteri zed by a ratio of microbial starter to bacterial cellulose sheet growth media of 1 : 4 v / v with the pH value of the mixture reaching 3 . 5- 6 , then letting the microbial starter mixture and the bacterial cellulose sheet growth media stand until a bacterial cellulose sheet is formed; g . harvesting the bacterial cellulose sheets that have been formed in the bacterial cellulose growth containers , when the growth media reaches a pH value of 3-4 and a Brix value of 1-4 ; h . cleaning the harvested bacterial cellulose sheets from yeast films using water ; i . performing initial-drying of harvested bacterial cellulose sheets to a moisture content of 5- 20% ; j . performing staining, flexibility improvementand deodorization of initial-dried bacterial cellulose sheets using mixed solutions of natural staining agents, natural ingredients for increasing flexibility and natural ingredients for deodorization; k. performing the final-drying of the resulting bacterial cellulose sheet from step j to a moisture content of 5-10% or a thickness of 0.4-1.2 mm, to obtain the final dry bacterial cellulose sheet product; l. coating the cotton-based fabric onto the final- dried bacterial cellulose sheet using an adhesive, which are then pressed together at a temperature of 80-100°C, to increase tear resistance and increase the ease of sewing on the dry bacterial cellulose sheet; and m. providing a water-repellent coating on the surface of dry cellulose sheet that is not given a fabric coating by using water-repellent materials which can be resins, waxes, or degradable polymers such as Polylactic Acid .

2. The process for producing bacterial cellulose sheets according to claim 1, wherein at the step of preparing the microbial starter propagation medium solution, 200-2000 grams of coffee husks are used per liter of medium solution.

3. The process for producing bacterial cellulose sheets according to claim 1, wherein at the step of performing the nutrient extraction of agricultural wastes, using agricultural wastes such as coffee husks (Coffea) , cocoa peels (Theobroma cacao) , jengkol peels ( Archi dendron pauciflorum) , cassava peels (Manihot esculenta) , Cilembu sweet potato peels (Ipomoea batatas') , pineapple peels (Ananas comosus) , andtomato peels ( Solanum lycopersi cum) .4 . The process for producing bacterial cellulose sheets according to claim 1 , wherein at the step of controlling the Brix value of the liquid extracted from agricultural waste , materials which can be used to increase the Brix value include molasses liquid or sorghum liquid .5 . The process for producing bacterial cellulose sheets according to claim 1 , wherein at the step of distributing the bacterial cellulose growth medium to bacterial cellulose growth containers , a ratio of the surface area of the growth medium in the containers to its height is 10-20 : 1 .6 . The process for producing bacterial cellulose sheets according to claims 1 and 5 , wherein at the step of distributing the bacterial cellulose growth medium to bacterial cellulose growth containers , the height of the growth media is preferred to be 5-20 cm .7 . The process for producing bacterial cellulose sheets according to claim 1 , wherein at the step of growing bacterial cellulose sheet in bacterial cellulose growth containers , characteri zed by microbial starter using 50-75% of the volume of starter stock prepared, to speed up the subsequent process of bacterial cellulose production by directly utili zing the remaining 25-50% microbial starter stock .8 . The process for producing bacterial cellulose sheets according to claim 1 , wherein after the step ofharvesting the bacterial cellulose sheets and prior to the initial-drying step, stacking of wet bacterial cellulose sheets is carried out for the harvested bacterial cellulose sheets having defects in the form of a hole nor a thickness of less than 1-1.5 cm, to produce initial-dried bacterial cellulose sheets that do not have a hole and have a minimum thickness of 1-1.5 cm.

9. The process for producing bacterial cellulose sheets according to claim 1, wherein at the step of staining, flexibility improvement and deodorization of the initial-drying results of bacterial cellulose sheets, using spurred mangrove wood (Ceriops tagal) , sappan wood (Biancaea sappan) , tarum leaves ( Indi gofera) , tageran wood (Cudrania j avanensis) , teak leaves (Tectona grand! s) , turmeric (Curcuma longa) , su j i leaves (Dracaena angusti folia) or pandan leaves ( Pandanus amaryllifolius) as natural staining agents, vegetable glycerol as a natural ingredient to increase the flexibility and citronella oil as a natural deodorizing ingredient.

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