Method for extracting nanocellulose from turmeric decoction pieces
Nanocellulose was extracted from turmeric slices through alkali treatment, biological bleaching and acid hydrolysis, which solved the problem of cellulose resource waste and achieved high-yield and high-quality nanocellulose production.
Patent Information
- Application Number
- CN202510874990.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-27
- Publication Date
- 2025-09-09
AI Technical Summary
In the prior art, the cellulose resources in turmeric slices are not fully utilized, resulting in a waste of biomass resources.
Nanocellulose was extracted from turmeric slices by a synergistic method of alkali treatment, biological bleaching, acid hydrolysis and mechanical treatment. Acid hydrolysis was performed using citric acid buffer and cellulase-xylanase complex enzyme, and bleaching was performed using a peracetic acid-laccase-oligoxylose synergistic system. Nanocellulose was obtained by dialysis and freeze-drying.
The yield of nano-turmeric cellulose is improved, the integrity of the fiber structure is maintained, the negative effects of acid corrosion and strong oxidants are avoided, and high-quality nano-cellulose products are obtained.
Smart Images
Figure CN120607633A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of turmeric application and relates to a method for extracting nanocellulose from turmeric decoction pieces. Background Art
[0002] Turmeric slices are derived from the rhizomes of the ginger plant Curcuma longa L. In traditional Chinese medicine theory, it has the effects of promoting blood circulation and promoting qi, promoting menstruation and relieving pain. In modern pharmacological research, turmeric has the effects of anti-myocardial ischemia, regulating blood lipids, anti-tumor, and anti-pulmonary fibrosis, and therefore has a wide range of clinical applications. In addition, turmeric can also be used as a dietary additive for food and beverages. The main components of turmeric rhizomes include curcumin and its derivatives, turmeric volatile oil, cellulose, ash, and protein, of which the cellulose content accounts for about 40%-50%. Currently, the main processing and industrial chain are to extract, separate, and purify its active ingredients. The fiber part of turmeric cannot be fully utilized, resulting in a large amount of waste of biomass resources. Summary of the Invention
[0003] The purpose of the present invention is to provide a method for extracting nanocellulose from turmeric slices, thereby solving the problem of the current lack of a method for extracting turmeric cellulose.
[0004] The technical solution adopted in the present invention is as follows: A method for extracting nanocellulose from turmeric slices comprises the following steps: S1, pretreatment: crushing and sieving the turmeric slices and then treating them with alkali to obtain pre-powder; S2, bleaching: bleaching the pre-powder with a bleaching agent to obtain a bleached powder; S3, acid hydrolysis: The bleached powder is subjected to acid hydrolysis with an acid hydrolyzing agent and then centrifuged, the supernatant is discarded, the mixture is adjusted to neutrality with NaOH, centrifuged, the supernatant is discarded again, and the mixture is washed with deionized water to obtain a first intermediate; S4. Mechanical treatment: Dispersing the first intermediate in deionized water in an ice bath to prepare a suspension, dispersing the suspension using a high-speed disperser, and then crushing the suspension using an ultrasonic crusher to obtain a second intermediate; S5. Extraction: Centrifuge the second intermediate and irradiate the supernatant with a laser pen. After the Tyndall effect appears, take the supernatant and add a certain amount of deionized water. Resuspend, centrifuge, and take the supernatant. Repeat this process and collect the supernatant until the Tyndall effect disappears. S6. Purification: Use a dialysis bag and deionized water as the dialysate to dialyze the collected supernatant. After the dialysis is completed, collect the purified liquid, filter it through a 0.1 μm filter membrane, collect the filtrate, and freeze-dry it. The freeze-dried powder is turmeric nanocellulose.
[0005] Furthermore, the acid hydrolyzing agent in step S3 includes citric acid buffer and cellulase-xylanase complex enzyme, and the acid hydrolyzing agent is prepared by the following method: A1. Prepare citric acid buffer with a pH of 4.8 and a concentration of 0.5 M using citric acid and sodium citrate. A2. Add cellulase-xylanase complex enzyme and Tween-80 to citric acid buffer, and mix them evenly by magnetic stirring to obtain an acid hydrolyzing agent.
[0006] Furthermore, the bleached powder is used as a substrate, the amount of cellulase added is 10 FPU / g of substrate mass, the amount of xylanase added is 5 U / g of substrate mass, and the material-liquid ratio of substrate to citric acid buffer is 1:20 (w / v).
[0007] Furthermore, step S3, acid hydrolysis: at 50° C., the acid hydrolyzing agent is mixed with the bleached powder, reacted for 8 hours for acid hydrolysis, and after the reaction is completed, heated to 90° C. for enzyme inactivation treatment, then centrifuged, discarded the supernatant, adjusted to neutrality with NaOH, centrifuged, discarded the supernatant again, and washed with deionized water to obtain a first intermediate.
[0008] Furthermore, based on the total amount of the bleaching agent, the bleaching agent includes the following components: 1.5% (v / v) peracetic acid, 50 U / mL laccase, 0.3 M citric acid, 2% (w / v) oligoxylose, 0.1% (v / v) Tween-80, and the remainder is citric acid buffer and pure water.
[0009] Furthermore, the bleaching agent is prepared by the following method: first preparing a citric acid buffer solution, adjusting the pH to 4.5, adding peracetic acid to the citric acid buffer solution, adding xylooligosaccharide after magnetic stirring, adding laccase after dissolving, and then adding Tween-80 dropwise, stirring evenly, and adding pure water to obtain the bleaching agent.
[0010] Furthermore, in step S2, bleaching: pre-powder and bleaching agent are mixed at a ratio of 1:15-20 (w / v), stirred at 60°C and 200 rpm for 3 hours, and after the reaction is completed, centrifuged at 11,000 rpm for 10 minutes, then washed with deionized water until neutral, and dried at 40°C to obtain a bleached powder.
[0011] Furthermore, the method for extracting nanocellulose from turmeric slices comprises the following steps: S1. Pretreatment: Grind the turmeric slices, pass them through a 140-mesh sieve, add 10% (w / w) NaOH at a solid-liquid ratio of 1:20, react at 45°C with magnetic stirring at 650 rpm for 2 h, centrifuge at 11,000 rpm for 10 min, discard the supernatant, adjust the pH to neutral with 10% (w / w) HCl, centrifuge again, wash with deionized water, and dry at 35°C to obtain pre-powder; S2, bleaching: bleaching the pre-powder with a bleaching agent to obtain a bleached powder; S3, acid hydrolysis: The bleached powder is subjected to acid hydrolysis with an acid hydrolyzing agent and then centrifuged, the supernatant is discarded, the mixture is adjusted to neutrality with NaOH, centrifuged, the supernatant is discarded again, and the mixture is washed with deionized water to obtain a first intermediate; S4. Mechanical treatment: Dispersing the first intermediate in deionized water in an ice bath to prepare a suspension, dispersing the suspension at 10,000 rpm for 10 min using a high-speed disperser, and then crushing the suspension using an ultrasonic crusher at 30% power for 10 min to obtain a second intermediate; S5. Extraction: The second intermediate was centrifuged at 8000 rpm for 15 min. The supernatant was irradiated with a laser pen. After the Tyndall effect appeared, the supernatant was collected. A certain amount of deionized water was added, and the mixture was resuspended, centrifuged, and the supernatant was collected. This process was repeated until the Tyndall effect disappeared. S6. Purification: Use a dialysis bag with MW = 3500Da and deionized water as the dialysate to dialyze the collected supernatant. After the dialysis is completed, collect the purified liquid, pass it through a 0.1 μm filter membrane, collect the filtrate, and freeze-dry it. The freeze-dried powder is turmeric nanocellulose.
[0012] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The present invention discloses a method for extracting nanocellulose from turmeric slices, utilizing the synergistic effects of alkali treatment, biological bleaching, acid hydrolysis, and mechanical treatment. While maintaining the integrity of the turmeric cellulose, it also breaks down barriers such as lignin and hemicellulose that encapsulate the turmeric cellulose, resulting in a high yield of nano-turmeric cellulose. 2. The present invention utilizes enzymatic hydrolysis and weak acid instead of strong acid for acid hydrolysis, thus avoiding acid corrosion caused by excessive hydrolysis and maintaining the integrity of the fiber structure; 3. The present invention designs a new bleaching agent that utilizes a peracetic acid-laccase-xylo-oligosaccharide synergistic system to efficiently decolorize and protect the fiber structure. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can also derive other relevant drawings based on these drawings without inventive effort, among which: Figure 1 This is a physical picture of the nanocellulose of the present invention. DETAILED DESCRIPTION
[0014] In order to make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present invention and are not intended to limit the present invention. That is, the embodiments described herein are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and illustrated in the drawings herein may be arranged and designed in various different configurations.
[0015] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely intended to represent selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.
[0016] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.
[0017] The features and performance of the present invention are further described in detail below with reference to the embodiments.
[0018] Example 1:
[0019] A preferred embodiment of the present invention provides a method for extracting nanocellulose from turmeric slices, comprising the following steps: S1. Pretreatment: Grind the turmeric slices, pass them through a 140-mesh sieve, add 10% (w / w) NaOH at a solid-liquid ratio of 1:20, react at 45°C with magnetic stirring at 650 rpm for 2 h, centrifuge at 11,000 rpm for 10 min, discard the supernatant, adjust the pH to neutral with 10% (w / w) HCl, centrifuge again, wash with deionized water, and dry at 35°C to obtain pre-powder; S2. Bleaching: pre-powder and bleaching agent were mixed at a ratio of 1:15 (w / v), stirred at 60°C and 200 rpm for 3 hours, and after completion of the reaction, centrifuged at 11,000 rpm for 10 minutes, washed with deionized water until neutral, and dried at 40°C to obtain the bleached powder; S3, acid hydrolysis: at 50 ° C, the acid hydrolyzing agent and the bleached powder were mixed and reacted for 8 hours for acid hydrolysis. After the reaction, the mixture was heated to 90 ° C to inactivate the enzyme, and then centrifuged. The supernatant was discarded, and the mixture was adjusted to neutral with NaOH, centrifuged, and the supernatant was discarded again. The mixture was washed with deionized water to obtain a first intermediate; S4. Mechanical treatment: Dispersing the first intermediate in deionized water in an ice bath to prepare a suspension, dispersing the suspension at 10,000 rpm for 10 min using a high-speed disperser, and then crushing the suspension using an ultrasonic crusher at 30% power for 10 min to obtain a second intermediate; S5. Extraction: The second intermediate was centrifuged at 8000 rpm for 15 min. The supernatant was irradiated with a laser pen. After the Tyndall effect appeared, the supernatant was collected. A certain amount of deionized water was added, and the mixture was resuspended, centrifuged, and the supernatant was collected. This process was repeated until the Tyndall effect disappeared. S6. Purification: Use a dialysis bag with MW = 3500Da and deionized water as the dialysate to dialyze the collected supernatant. After the dialysis is completed, collect the purified liquid, pass it through a 0.1 μm filter membrane, collect the filtrate, and freeze-dry it. The freeze-dried powder is turmeric nanocellulose.
[0020] The acid hydrolyzing agent in step S3 includes citric acid buffer and cellulase-xylanase complex enzyme, and the acid hydrolyzing agent is prepared by the following method: A1. Prepare citric acid buffer with a pH of 4.8 and a concentration of 0.5 M using citric acid and sodium citrate. A2. Add cellulase-xylanase complex enzyme and Tween-80 to citric acid buffer, and mix them evenly by magnetic stirring to obtain an acid hydrolyzing agent.
[0021] The bleached powder was used as a substrate, the amount of cellulase added was 10 FPU / g of substrate mass, the amount of xylanase added was 5 U / g of substrate mass, and the material-liquid ratio of substrate to citric acid buffer was 1:20 (w / v).
[0022] The total amount of the bleaching agent was used as the calculation standard. The bleaching agent included the following components: 1.5% (v / v) peracetic acid, 50 U / mL laccase, 0.3 M citric acid, 2% (w / v) xylo-oligosaccharide, 0.1% (v / v) Tween-80, and the remainder was citric acid buffer and purified water.
[0023] The bleaching agent is prepared by the following method: first preparing a citric acid buffer solution, adjusting the pH to 4.5, adding peracetic acid to the citric acid buffer solution, mixing by magnetic stirring, adding oligoxylose, dissolving the oligoxylose, adding laccase, and then dropping Tween-80, stirring evenly, and adding pure water to obtain the bleaching agent.
[0024] Figure 1 This is a physical picture of the product of the present invention, which is milky white and translucent, with no impurities visible to the naked eye.
[0025] Example 2:
[0026] This example is based on Example 1, but differs from Example 1 in that: S2, bleaching: the pre-powder and the bleaching agent are mixed at a ratio of 1:17.5 (w / v), stirred at 60°C and 200 rpm for 3 hours, and after the reaction, centrifuged at 11,000 rpm for 10 minutes, then washed with deionized water until neutral, and dried at 40°C to obtain the bleached powder.
[0027] Example 3:
[0028] This example is based on Example 1, but differs from Example 1 in that: S2, bleaching: the pre-powder and the bleaching agent are mixed at a ratio of 1:20 (w / v), stirred at 60°C and 200 rpm for 3 hours, and after the reaction, centrifuged at 11,000 rpm for 10 minutes, then washed with deionized water until neutral, and dried at 40°C to obtain a bleached powder.
[0029] Comparative Example 1:
[0030] Comparative Example 1 is based on Example 1, and differs from Example 1 in that, in step S2, bleaching, sodium chlorite mixture is used as a bleaching agent and added to the pre-powder twice with an interval of 1 hour. The reaction temperature is 20° C. and the magnetic stirring speed is 650 rpm. After the reaction is completed, the mixture is centrifuged at 11,000 rpm, the pH is adjusted to 7, and the precipitate is washed 2-3 times with deionized water and dried to obtain a bleached powder. The sodium chlorite mixture includes sodium chlorite, sodium hydroxide, glacial acetic acid, and ultrapure water. 0.4g of sodium chlorite, 0.6g of sodium hydroxide, and 1.9ml of glacial acetic acid are added to each gram of pre-powder.
[0031] Comparative Example 2:
[0032] This comparative example 1 is based on Example 1, and differs from Example 1 in that S3 and acid hydrolysis in this comparative example are as follows: a certain amount of bleached powder was taken, 60% (w / w) H2SO4 was added at a material-liquid ratio of 1:20, the mixture was reacted at 45°C for 5 hours, the magnetic stirring speed was 650 rpm, and after the reaction was completed, the mixture was centrifuged at 11000 r / min for 20 minutes, the supernatant was discarded, the pH was adjusted to neutral with NaOH, the mixture was centrifuged, the supernatant was discarded again, and the mixture was washed twice with deionized water to obtain a first intermediate.
[0033] Comparative Example 3:
[0034] Comparative Example 1 is based on Example 1. The difference from Example 1 is that no bleaching treatment is performed in this comparative example. After the pretreatment in step S1, the process directly proceeds to the acid hydrolysis treatment in step S3.
[0035] Comparative Example 4:
[0036] Comparative Example 1 is based on Example 1. The difference from Example 1 is that acid hydrolysis treatment is not performed in this comparative example, and the mechanical treatment of step S4 is directly performed after bleaching in step S2.
[0037] Comparative Example 5:
[0038] Comparative Example 1 is based on Example 1. The difference from Example 1 is that the mechanical treatment in step S4 is not performed in this comparative example, and the extraction process in step S5 is directly performed after acid hydrolysis in step S3.
[0039] Test Example 1:
[0040] The product yields of Examples 1-3 and Comparative Examples 1-5 were tested, yield (%) = [final mass of freeze-dried nanocellulose powder (g) / initial dry mass of turmeric slices (g)] × 100%. The results are shown in Table 1.
[0041] Table 1 Yield of target product
[0042] Strong acid or strong oxidizing bleaching agent will affect the product yield. The present invention adopts a milder and more effective bleaching method and acid hydrolysis to replace the existing treatment method, and the product yield is higher.
[0043] Test Example 2:
[0044] The apparent shapes of the products of Examples 1-2 and Comparative Examples 1-5 were tested, and the results are shown in Table 2.
[0045] Table 2 Appearance of the product Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 color milky milky milky light yellowish brown Off-white dark yellow brownish yellow cream Dispersibility (in aqueous solution) Uniform Uniform Uniform Sedimentation and stratification Partial flocculation settlement Fiber flocs Partial flocculation Impurity situation No impurities No impurities No impurities Visible black impurities Visible black impurities - Floccules appear Floccules appear The product prepared by the invention is clean and of high quality.
[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions and improvements made by any technician familiar with the field within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A method for extracting nanocellulose from turmeric slices, characterized in that: The following steps are involved: S1, pretreatment: crushing and sieving the turmeric slices and then treating them with alkali to obtain pre-powder; S2, bleaching: bleaching the pre-powder with a bleaching agent to obtain a bleached powder; S3, acid hydrolysis: The bleached powder is subjected to acid hydrolysis with an acid hydrolyzing agent and then centrifuged, the supernatant is discarded, the mixture is adjusted to neutrality with NaOH, centrifuged, the supernatant is discarded again, and the mixture is washed with deionized water to obtain a first intermediate; S4. Mechanical treatment: Dispersing the first intermediate in deionized water in an ice bath to prepare a suspension, dispersing the suspension using a high-speed disperser, and then crushing the suspension using an ultrasonic crusher to obtain a second intermediate; S5. Extraction: Centrifuge the second intermediate and irradiate the supernatant with a laser pen. After the Tyndall effect appears, take the supernatant and add a certain amount of deionized water. Resuspend, centrifuge, and take the supernatant. Repeat this process and collect the supernatant until the Tyndall effect disappears. S6. Purification: Use a dialysis bag and deionized water as the dialysate to dialyze the collected supernatant. After the dialysis is completed, collect the purified liquid, filter it through a 0.1 μm filter membrane, collect the filtrate, and freeze-dry it. The freeze-dried powder is turmeric nanocellulose.
2. A method for extracting nanocellulose from turmeric slices according to claim 1, characterized in that: The acid hydrolyzing agent in step S3 includes citric acid buffer and cellulase-xylanase complex enzyme, and the acid hydrolyzing agent is prepared by the following method: A1. Prepare citric acid buffer with a pH of 4.8 and a concentration of 0.5 M using citric acid and sodium citrate. A2. Add cellulase-xylanase complex enzyme and Tween-80 to citric acid buffer, and mix them evenly by magnetic stirring to obtain an acid hydrolyzing agent.
3. A method for extracting nanocellulose from turmeric slices according to claim 2, characterized in that: The bleached powder was used as a substrate, the amount of cellulase added was 10 FPU / g of substrate mass, the amount of xylanase added was 5 U / g of substrate mass, and the material-liquid ratio of substrate to citric acid buffer was 1:20 (w / v).
4. A method for extracting nanocellulose from turmeric slices according to claim 3, characterized in that: S3. Acid hydrolysis: At 50°C, an acid hydrolyzing agent is mixed with the bleached powder, and the mixture is reacted for 8 hours for acid hydrolysis. After the reaction, the mixture is heated to 90°C for enzyme inactivation, and then centrifuged. The supernatant is discarded, and the mixture is adjusted to neutral with NaOH, centrifuged, and the supernatant is discarded again. The mixture is washed with deionized water to obtain a first intermediate.
5. A method for extracting nanocellulose from turmeric slices according to claim 1, characterized in that: The total amount of the bleaching agent was used as the calculation standard. The bleaching agent included the following components: 1.5% (v / v) peracetic acid, 50 U / mL laccase, 0.3 M citric acid, 2% (w / v) xylo-oligosaccharide, 0.1% (v / v) Tween-80, and the remainder was citric acid buffer and purified water.
6. A method for extracting nanocellulose from turmeric slices according to claim 5, characterized in that: The bleaching agent is prepared by the following method: first preparing a citric acid buffer solution, adjusting the pH to 4.5, adding peracetic acid to the citric acid buffer solution, mixing by magnetic stirring, adding oligoxylose, dissolving the oligoxylose, adding laccase, and then dropping Tween-80, stirring evenly, and adding pure water to obtain the bleaching agent.
7. A method for extracting nanocellulose from turmeric slices according to claim 5, characterized in that: Step S2, bleaching: pre-powder and bleaching agent are mixed at a ratio of 1:15-20 (w / v), stirred at 60°C and 200 rpm for 3 hours, centrifuged at 11,000 rpm for 10 minutes after the reaction, then washed with deionized water until neutral, and dried at 40°C to obtain the bleached powder.
8. A method for extracting nanocellulose from turmeric slices according to claim 1, characterized in that: The following steps are involved: S1. Pretreatment: Grind the turmeric slices, pass them through a 140-mesh sieve, add 10% (w / w) NaOH at a solid-liquid ratio of 1:20, react at 45°C with magnetic stirring at 650 rpm for 2 h, centrifuge at 11,000 rpm for 10 min, discard the supernatant, adjust the pH to neutral with 10% (w / w) HCl, centrifuge again, wash with deionized water, and dry at 35°C to obtain pre-powder; S2, bleaching: bleaching the pre-powder with a bleaching agent to obtain a bleached powder; S3, acid hydrolysis: The bleached powder is subjected to acid hydrolysis with an acid hydrolyzing agent and then centrifuged, the supernatant is discarded, the mixture is adjusted to neutrality with NaOH, centrifuged, the supernatant is discarded again, and the mixture is washed with deionized water to obtain a first intermediate; S4. Mechanical treatment: Dispersing the first intermediate in deionized water in an ice bath to prepare a suspension, dispersing the suspension at 10,000 rpm for 10 min using a high-speed disperser, and then crushing the suspension using an ultrasonic crusher at 30% power for 10 min to obtain a second intermediate; S5. Extraction: The second intermediate was centrifuged at 8000 rpm for 15 min. The supernatant was irradiated with a laser pen. After the Tyndall effect appeared, the supernatant was collected. A certain amount of deionized water was added, and the mixture was resuspended, centrifuged, and the supernatant was collected. This process was repeated until the Tyndall effect disappeared. S6. Purification: Use a dialysis bag with MW = 3500Da and deionized water as the dialysate to dialyze the collected supernatant. After the dialysis is completed, collect the purified liquid, pass it through a 0.1 μm filter membrane, collect the filtrate, and freeze-dry it. The freeze-dried powder is turmeric nanocellulose.