Sodium Hydroxide Extraction Research Articles

Effects of different extraction solvents on the compositions, primary structures, and anti-inflammatory activity of pectin from sweet potato processing by-products

To examine the effects of different solvents on the molecular weight, yield, chemical composition, and bioactivity of pectins, four RG-I type pectins were separately extracted from sweet potato residue (SPR) using hot water extraction (HWSP), sodium hydroxide extraction (SHSP), hydrochloric acid extraction (HASP), and chelating agents (CASP). The results showed that the four pectin samples comprised GalUA, Gal, Rha, Ara, Glc, GlcUA, Man, and Xyl components. Among these components, GalA content was the highest in all four pectins. SHSP exhibited relatively higher yield (3.16 %, w/w). Additionally, SHSP exhibited a lower molecular weight (44.49 kDa) and the largest proportion of the RG-I region (75.42 %) compared with other extraction methods. On the contrary, HASP showed relatively lower yield (2.14 %, w/w), and its corresponding prepared pectin had relatively high molecular weight (69.81 kDa) and the minimum range of RG-I region (46.87 %) compared with HWSP, SHSP, and CASP. The anti-inflammation effect of the four SPR pectin samples was investigated using in vitro experiments. Results showed that all of SPR pectin significantly inhibited the levels of IL-1β, IL-6, and TNF-α in lipopolysaccharide (LPS)-treated iBMDM macrophage cells. The preliminary structure-activity relationship between pectin structure and anti-inflammatory activity was also analyzed. SPR pectin can be developed as a potential bioactive ingredient for applications in the food and medicine industries.

Potential of Bioactive Protein and Protein Hydrolysate from Apis mellifera Larvae as Cosmeceutical Active Ingredients for Anti-Skin Aging.

This study aimed to extract bioactive proteins and protein hydrolysates from Apis mellifera larvae and assess their potential application in cosmetics as well as their irritation properties. The larvae were defatted and extracted using various mediums, including DI water, along with 0.5 M aqueous solutions of sodium hydroxide, ascorbic acid, citric acid, and hydrochloric acid. Subsequently, the crude proteins were hydrolyzed using the Alcalase® enzyme. All extracts underwent testing for antioxidant activities via the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and Griess assays. Anti-aging properties were evaluated in terms of anti-collagenase and anti-hyaluronidase effects. Irritation potential was assessed using the hen's egg chorioallantoic membrane (HET-CAM) test. The results revealed that the sodium hydroxide extraction showed promising outcomes in terms of yield, protein content, and effectiveness in inhibiting hyaluronidase, with the highest inhibition at 78.1 ± 1.5%, comparable to that of oleanolic acid. Conversely, crude protein extracted with ascorbic acid and its hydrolysate showed notable antioxidant and collagenase-inhibitory activities. Remarkably, their anti-collagenase effects were comparable to those of ascorbic acid and lysine. Additionally, it demonstrated safety upon testing with the CAM. In conclusion, the findings provided valuable insights into the utilization of A. mellifera larval proteins as active ingredients with a wide range of cosmeceutical applications, particularly due to their antioxidant, anti-aging, and low irritation properties, which hold significant promise for anti-skin wrinkles.

Rice straw-based sustainable food packaging material with improved strength and barrier properties: Development and characterization

Sustainable food packaging paper with high barrier and strength properties was developed with rice straw nanocellulose materials. Pulping and bleaching of rice straw were performed using an organosolv pulping and DED (D: chlorine dioxide bleaching; E: sodium hydroxide extraction) bleaching sequence. Bleached rice straw pulp was refined to 90°SR using a laboratory Valley beater. The laboratory handsheets were prepared using pulp slurry at 40°SR and 90°SR. The handsheets of cellulose nanofibrils (CNFs) made of highly refined pulp (90°SR) were surface sized using alkyl ketene dimer (AKD) wax to increase the barrier properties of paper for selective food packaging applications. The paper samples were tested for mechanical, optical, surface, and barrier properties, including tensile index, burst index, tearing index, bending stiffness, elongation, porosity, apparent density, opacity, Cobb value, water vapor transmission rate (WVTR), oil and grease resistance, and contact angle. The refined pulp (90°SR) was analyzed using field-emission scanning electron microscopy (FE-SEM), and it was observed that the morphology of the developed fibers changes to the nanoscale (<100 nm) for at least one dimension. The particle size distribution of the refined pulp using DLS analyzer also confirmed the cellulose fibers to near nanoscale. It was concluded that nanofibers were formed by a high degree of the mechanical pulp refining process and found to be much more economical than alternative processes in this direction. The sample handsheets of CNFs showed good strength and barrier properties. The barrier properties further increased when surface sizing was done using low-cost, nontoxic, and biodegradable AKD wax.

Chemical extraction and its effect on the properties of cordleaf burbark (Triumfetta cordifolia A. rich) fibres for the manufacture of textile yarns

Tropical Triumfetta cordifolia (TC) fibre extracted from the equatorial region of Cameroon has been characterized as a potential fibre for textiles. An investigation of extraction parameters to soften this fibre is crucial to use it as a biobased material in the spinning process. To obtain textile quality fibres, 34 sodium hydroxide extraction tests were carried out to study the effect of extraction conditions on its characteristics. Thus, three levels of concentrations (0.5, 1.0 and 1.5 wt%), temperatures (80, 100 and 120 °C) and durations (120, 180 and 240min) were used for extraction by cooking, and at room temperature, durations of 120, 150 or 180 min with three concentrations (2.5, 3.0 and 3.5 wt%) were considered. Only 6 combinations produced fibres that were clear and soft to the touch, without defects (corrugations, stuck fibres) and without residual bark epidermis at the macroscopic scale. For these fibres, the dissolution of non-cellulosic substances, morphological, physical, thermal and mechanical properties depended on the austerity of the alkaline retting. Under mild conditions, the SEM surfaces of the fibres showed large residues of the middle lamella, which made the lignin content (10 wt%) and hydrophilic function higher. Under medium conditions, the fibre surfaces were clean and slightly wrinkled (at 80 °C; 120min). Under severe conditions, heterogeneous transverse shrinkage and wrinkling were observed and accompanied by cellulose degradation (39 wt%) with a significant reduction in tenacity at 16cN/tex. The medium extraction conditions were considered more effective, and their fibres showed cellulose content up to 49 wt%, density up to 1.39 g cm−3, “Fickian” moisture absorption kinetics with saturation up to 11 wt%, thermal stability up to 237 °C, Young's modulus up to 3.7 GPa, tensile strength up to 113 MPa and tenacity up to 40cN/tex. These new results were compared with lignocellulosic textile fibres in the literature, showing similarity with banana, sisal and jute fibres.

Study on adsorption and recovery utilization of phosphorus using alkali melting-hydrothermal treated oil-based drilling cutting ash

Oil-based drill cutting ash (OBDCA) was treated by alkali melting-hydrothermal method and used as novel adsorbent (AM-HT-OBDCA) for the recovery of phosphorus (P) in water body. The experiment parameter for preparation of AM-HT-OBDCA was optimized, including alkali melting ratio (MOBDCA: MNaOH), alkali melting temperature and hydrothermal temperature. The adsorption process of phosphorus on AM-HT-OBDCA was fit well with the pseudo-second-order model and the Langmuir model. The calculated theoretic adsorption capacity of phosphorus on AM-HT-OBDCA was 62.9 mg/g. The adsorption behavior was spontaneous and endothermic. The effect of pH value and interfering ions on the adsorption of phosphorus in AM-HT-OBDCA was investigated. The main existing form of adsorbed phosphorus on AM-HT-OBDCA was sodium hydroxide extraction form phosphorus (NaOH–P), including iron form phosphorus (Fe–P) and aluminum form phosphorus (Al–P). Precipitation and ligand exchange were the main mechanisms of phosphorus adsorption on AM-HT-OBDCA. The AM-HT-OBDCA used for phosphorus adsorption (AM-HT-OBDCA-P) could be further utilized as fertilizer to promote plant growth. The results of this study provide fundamental data and evaluation support for resource utilization of OBDCA. These results will also provide a reference for the adsorption and recovery utilization of phosphorus using solid waste-based adsorbent.

Intensification and Calculation of Process of Sodium Hydroxide Extraction from Fibrous Materials

Intensification and Calculation of Process of Sodium Hydroxide Extraction from Fibrous Materials

Wound healing efficacy of biocompatible hydroxyapatite from bovine bone waste for bone tissue engineering application

Extraction of biocompatible implantable biomaterials from bio-waste is a considerable strategy to protect environmental issues as well as human wellness. Hence, this work aimed to extract the hydroxyapatite (HAP) from beef bone (BB) by acid/alkali treatment, and calcination process. The hydrochloric acid (1 M), and sodium hydroxide (1 M) extraction followed by calcination at 600 °C for 5 h were facilitated to obtain the good quality of bovine bone-derived hydroxyapatite (BB-HAP). The characteristics of BB-HAP were demonstrated through XRD, FTIR, SEM, ICP-OES, and TGA analysis. The characteristics features of BB-HAP were compared with standard hydroxyapatite (Std-HAP). The FTIR spectrum confirmed the presence of carbonate and phosphate functional groups in BB-HAP, which is similar to Std-HAP. Further, XRD and SEM analysis confirmed the hexagonal crystalline structure of BB-HAP with size of 120 ± 12.5 nm. ICP-OES analysis evidenced the existence of Ca (40.42%), P (18.51%), Mg (0.55%), Na (0.22%), and Sr (0.05%) in BB-HAP. In vitro cytotoxicity assay confirmed that BB-HAP did not cause cytotoxicity to NIH3T3 cells, and augmented in vitro wound-healing activity. Hence, this study concluded that BB-HAP was biocompatible that would be used for the development of wound dressing and implantable material.

Rheological behaviour of water based mud formulated with sodium hydroxide (NaOH) plant extracts

The rheological behaviour of drilling mud formulated with sodium hydroxide extracts of Bitter-leaf (BL), Pawpaw (PL), Almond (AL) and Moringa (ML) leaves applied as surfactant (emulsifiers) was studied. The rheological properties (plastic viscosity (PV), yield point (YP), and gel strength) of the mud were measured using standard procedures. The mud specific gravity for BLEM and PLEM was observed to give same value (1.08) as that of the C1 mud. pH of the formulated mud were all alkaline and in the order BLEM (8.6) > PLEM (8.3) > ALEM (8.3) > C1(8.3) > MLEM (8.2) > C2 (8.2). The highest PV (19cP) was recorded by PLEM at 30ºC, while the least value (6cP) was by C2 at 60ºC temperatures. Highest YP (70 1b/100ft2) was recorded by C2 while the lowest YP value (22 1b/100ft2) by C1 both at 30ºC. Gel strength at 10 seconds showed reduction in value as the temperature increased for MLEM, ALEM, C2 and C1 formulated mud and recorded maximum of 45 1b/100 ft2 at 30ºC for C2 while the lowest gel strength was reported by C1 at 60ºC. The results obtained from the study showed that the various alkaline plant extracts used as emulsifying agent have no negative effect on the rheological properties of the formulated mud, rather it enhances the rheological properties even after aging of the mud at 65oC. These results therefore, show the need to use the various plant extracts as alternative additive (emulsifying agent) in the formulation of water based drilling mud.

Integrated biorefinery of aquatic fern Azolla filiculoides for enhanced extraction of phenolics, protein, and lipid and methane production from the residues

Azolla filiculoides is an aquatic fern native to tropical regions, and because of its unique composition, it was subjected to integrated biorefineries for biochemicals and bioenergy production. The compositional analysis showed that its raw biomass contained 41.4% carbohydrates, comprising galactan, glucan, and arabinan, 12% lignin, and 10.3% inorganic matter. Lipids, proteins, and phenolic compounds were extracted from the biomass and analyzed by different methods to enhance extraction yield and estimate their nutritional values. The residues remained after the (sequential) extraction of the major biochemicals was subjected to biogas production. A maximum lipid yield of 18.1% was obtained from the biomass, which was rich in palmitic acid and eicosapentaenoic acid (EPA). EPA, an omega-3 fatty acid with wide applications as a food supplement, accounted for 39.8% of total fatty acids, corresponding to 72 mg/g biomass. Two protein extraction methods, i.e., ultrasound-assisted water followed by sodium hydroxide extraction and sequential extraction by hot trichloroacetic acid, were applied. Using the first method at the optimum conditions, up to 24.4% protein was obtained, while a maximum 11.9% water-soluble protein was isolated by applying ultrasound-assisted extraction. In the amino acid profile of the fern protein, glutamic acid was the most abundant component with 20.5%, followed by threonine. Up to 37.9% of total amino acids were composed of essential amino acids that showed a high nutritional value of the fern protein. The total phenolic content of 27.2 mg gallic acid equivalent per 100 g of biomass was obtained. In the HPLC analysis, chlorogenic acid, luteolin, caffeic acid, and tannic acid were detected in which caffeic acid had the highest concentration of 18.5 mg/100 g raw material. Tannic acid removal was the most effective pretreatment for enhanced biomethane production. A maximum cumulative methane yield of 250.1 mL/g-VS was obtained from tannic acid-free biomass, which was 12% higher than that of the raw biomass.

Determination of the Bond Strength of Wood Veneer and Geopolymer Matrix by Means of a Pull-Out Test

The bonding strength of wood veneer (Picea abies) attached between a geopolymer matrixes were investigated by means of a pull-out test. Effects of pre-treatment of wood on the bonding strength were applied whereas a strong influence of pre-treatment on bonding strength could be observed. The treatment of wood veneer showed that using wet veneer (~90% moisture content) leads to the best results compared to untreated dry (~12% moisture content) veneer. Furthermore, the effects of sodium hydroxide extraction and sodium silicate treatment were examined. The lignin UV absorbance values in treated wood, obtained by scanning ultraviolet microspectrophotometry (UMSP), do not show any significant changes in absorbance which mean that there were no complex changes in phenolic wood components, including modification of the lignin side chains. It can be said that the alkaline environment needed for geopolymer was not the main problem that limits wood (Picea abies)-geopolymer compatibility.

Potential Alterations in the Chemical Structure of Soil Organic Matter Components during Sodium Hydroxide Extraction

The use of alkaline solutions, especially 0.1 to 0.5 M NaOH solutions, for the extraction of humic substances (HS) from soils is controversial because of the potential for chemical and physical alteration of the organic materials in soils. Therefore, it is important to investigate the effects of NaOH extraction on the chemical structure of natural organic matter (NOM) in terrestrial ecosystems. By using solid‐state nuclear magnetic resonance, we investigated the impact of NaOH and water extractions on the chemical structure of insoluble and extractable fractions of three model components of NOM: cellulose, van Soest lignin, and peat. We found both sp2–hybridized and carboxyl C groups occurred in the NaOH‐extractable cellulose fraction relative to the bulk cellulose. Compounds solubilized from the lignin by treatment with 0.1 M NaOH were dominated by aromatic C‐O, aromatic C, and OCH3 functional groups, indicating that some free phenolic monomers were extracted by the alkaline solution. Compared with the bulk peat, the concentration of COO/NCO and sp2–hybridized C in NaOH‐reconstituted peat sample increased by 40 and 5%, respectively, whereas the concentration of carbohydrate C decreased by 14%. In summary, the chemical structures of cellulose, van Soest lignin, and the peat were altered to some extent by the 0.1 M NaOH extraction. These observations provide useful context in the consideration of potential alterations in chemical composition when one interprets results of HS extractions employing NaOH solutions. Future research will establish the proportion of these alterations that may result from an alternative, slower procedure for acidifying solutions after NaOH extraction.Core Ideas Some unintended chemical reactions may occur in SOM during alkaline extraction. Alkaline extraction may cause an increase of COO/NCO and sp2–hybridized C groups. Alkaline extraction may induce a decrease of O‐alkyl C and anomeric C groups.

The effects of 4-acetamido-TEMPO-mediated oxidation on the extraction components of thermomechanical pulp

4-Acetamido-TEMPO-mediated oxidation was carried out on thermomechanical pulp (TMP) to further investigate the extraction components of the oxidized pulp. Successive extractions on non-oxidized, bleached and oxidized TMP have shown that components were easier to extract from the oxidized pulp. The pulp lignin content demonstrated that the highest content of lignin was removed by sodium hydroxide extraction. Moreover, more than two times the amount lignin was extracted from oxidized pulp compared to non-oxidized pulp. The measured carboxylic groups showed that the highest amounts of the oxidized components were removed after the first extraction. However, after each extraction, reduced but still significant amounts of carboxylic groups were present in the extracted material. Thermogravimetric analysis showed that 4-acetamido-TEMPO oxidation treatment induced a decrease in the fibre degradation temperature caused by a weakening in the fibre structure. The results also demonstrated that some components of the highly oxidized pulp were more easily dissolved because of the critical extraction conditions. Furthermore, the recovered precipitate in the extraction solvent had different XPS characteristics according to the initial pulp treatment. The analysis of the oxidized TMP precipitate showed that the precipitate from hot water extraction was the most highly oxidized, while the precipitate from sodium hydroxide extraction approached pure lignin characteristics.

Improving antifouling performance for the harvesting of Scenedesmus acuminatus using Fe2O3 nanoparticles incorporated PVC nanocomposite membranes

ABSTRACTMembrane filtration provided a potential solution to get high quality microalgae biomass and recyclable medium. However, the fouling of membrane by microalgae cells and organic matter greatly affects membrane harvesting efficiency. In this study, membrane performance was tested in terms of flux declining and backwashing recovery for microalgal harvesting. Compared with the unmodified poly(vinyl chloride) (PVC) membrane, the membrane with 1.0% Fe2O3 incorporation had a 66% increase in average flux, reaching 138 L m− h−1. Foulants on the membrane surface were characterized using attenuated total reflection‐Fourier transform infrared (ATR‐FTIR) and confocal laser scanning microscope (CLSM), as well as sodium hydroxide extraction followed by total organic carbon (TOC) quantification and fluorescence excitation–emission matrix (FEEM) identification of organic components. FEEM and TOC analysis of the extracted foulants revealed that the surface of 1.0% Fe2O3 incorporated membrane had less fouling than the unmodified PVC membrane, which may be attributed to its hydrophilicity after Fe2O3 incorporation. CLSM analysis and ATR‐FTIR analysis of the fouled membrane surface further revealed that the protein substance on the 1.0% Fe2O3 incorporated PVC membrane was lower than those in the unmodified membrane, which further confirmed the enhanced antifouling performance of the 1.0% Fe2O3 incorporated PVC membrane. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47685.

Optimizing and predicting degree of hydrolysis of ultrasound assisted sodium hydroxide extraction of protein from tea (Camellia sinensis L.) residue using response surface methodology.

Response surface methodology was employed to investigate the effect of sodium hydroxide concentration (X 1: 0.05-0.15M), sonication time (X 2: 5-15min), ultrasonic power (X 3: 150-450W/L), and solid-liquid ratio (X 4: 20-60g/L) on the optimization of protein extraction from tea residue. Single frequency countercurrent ultrasound (SFCU) was employed to assist the extraction and subsequent hydrolysis of the protein. Optimal extraction conditions were established and response surfaces were generated using mathematical models. There were positive linear and negative quadratic effects of extraction variables on protein yield. The optimal predicted protein yield of 138.9mg/g was obtained under the optimum conditions of concentration of 0.13M, extraction time of 13min, ultrasonic power of 377W/L and solid-liquid ratio of 51.5g/L. A model for the degree of hydrolysis of the extraction process was also obtained which gave a predicted and experimental value of 8.4% and 7.5% respectively. Essential amino acid content of 36.7% was obtained under optimal conditions.

A recyclable hydroxyl functionalized polyindole hydrogel for sodium hydroxide extraction via the synergistic effect of cation-π interactions and hydrogen bonding.

We have successfully constructed a new type of recyclable indole-based hydrogel, which exhibited highly effective extraction behavior for hydroxide via the synergistic effect of cation-π interactions and hydrogen bonds. More interestingly, the absorption performance could be visually detected by taking advantage of the color altering effect of the host-guest interactions.

Polyvinyl alcohol-boronate gel for sodium hydroxide extraction.

Gels formed from commercially available polyvinyl alcohol (PVA) and 1,4-benzene diboronic acid (BdBA) in DMSO absorb NaOH efficiently from a bulk aqueous solution decreasing its pH.

Anti-proliferative activity of a purified polysaccharide isolated from the basidiomycete fungus Paxillus involutus

A growth-inhibitory polysaccharide (GIPinv) was purified using size-exclusion and ion-exchange chromatography from the fourth sodium hydroxide extraction step of a fungus found in British Columbia. The fungus was genetically identified as a member of the Paxillus involutus complex. GIPinv has an average molecular weight of 229kDa and is a heteroglycan composed of glucose (65.9%), galactose (20.8%), mannose (7.8%), fucose (3.2%) and xylose (2.3%). GC–MS methylation analysis suggests that GIPinv has mixed linkages in the backbone containing (1→6)-Gal (25.5%), (1→4)-Glc (18.3%), (1→6)-Glc (8.3%), (1→3)-Glc (5.3%) and (1→2)-Xyl (4.5%). GIPinv has branching points at (1→2, 6)-Man (8.6%) and (1→3, 6)-Man (4.9%) having unsubstituted fucose (8.3%) and glucose (16.3%) as terminal sugars. GIPinv had growth-inhibitory activity against several cancer cell lines and triggered apoptosis. GIPinv should be further explored as a potential anti-cancer agent and a unique polysaccharide.

Chemical composition of some plantation wood species (Eucalyptus saligna, Cupressus lusitanica and Eucalyptus paniculata) and assessment of compatibility with plaster

The aim of this work was to evaluate the chemical composition of some plantation wood and the assessment of their compatibility with plaster. A quantitative analysis of the chemical composition each of the species (Eucalyptus saligna, Cupressus lusitanica and Eucalyptus paniculata) was carried out, followed by chemical compatibility evaluation using different types of wood particles. The quantitative analyses were carried out on wood powder of size between 0.27 and 0.30 mm. The results obtained were 2.4, 3.4 and 1.6% for ethanol–benzene extract (EAB); 2.6, 3.2 and 2.4% for hot water extract (EE); 12.4, 21.6 and 12.1% for 1% sodium hydroxide extract (ES); 48.6, 48.4 and 40.4% for cellulose content (C); 34.8, 34.3 and 36.3% for lignin content (L); then 0.1, 0.6, 0.3% for ash content (CE) respectively of E. saligna, C. lusitanica and E. paniculata. Chemical compatibility CA was measured from hydration temperature curves as a function of time using the area method. The results showed that compatibility CA decreased from 100 to 68% as the wood content in the composite increased up to 15% for all species and types of particles used. At this minimum value, the species was still considered as highly compatible in accordance with literature. Although compatibility is good, it decreased in the order E. paniculata followed by E. saligna and then C. lusitanica, the least compatible due to the inhibiting action of extractives.

The integration of different pretreatments and ionic liquid processing of eucalyptus: Hemicellulosic products and regenerated cellulose fibers

The integrated biorefinery of woody biomass for the synthesis of cellulose materials and hemicellulosic products is nowadays considered attractive towards a sustainable standpoint. The effects of alkaline, hydrothermal and acidic pretreatments on the preparation of regenerated cellulose fibers from eucalyptus via ionic liquid wet-spinning, and the isolation and conversion of hemicelluloses using different pretreatments were explored. The structure of alkali-soluble hemicelluloses via 5% sodium hydroxide extraction was deduced to be D-Glc p-4-O-methyl-d-glucurono-d-xylan. The xylooligosaccharides (XOS, DP 2–6) yields by hydrothermal (180°C, 30min) and 0.25mol/L dilute sulphric acid (90°C, 1h) pretreatments were 37.30 and 52.12mg/g respectively, and the main XOS productions were xylobiose (11.19–15.68mg/g) and xylotriose (10.03–11.63mg/g). The isolated cellulose could be completely dissolved in 1-butyl-3-methylimidazolium acetate ([bmim]OAc) and the chemical conformation of the regenerated fibers was similar to cellulose II. The viscosity of the spinning dopes, the morphology, molecular weights and mechanical strength of the fibers were highly dependent on the type of pretreatments. The multifilament fibers exhibited a smooth morphology and good mechanical property (1.55–2.01 cN/dtex) being close to commercial viscose rayon. The conversion of hemicelluloses to value-added products was achieved via different pretreatments in conjugation with cellulose spinning process.

Enhanced Release of Immunostimulating β-1,3- Glucan by Autodigestion of the Lingzhi Medicinal Mushroom, Ganoderma lingzhi (Agaricomycetes).

Ganoderma lingzhi is a widely used medicinal mushroom that has antioxidative effects, ameliorates insulin resistance, and improves quality of life in patients with metabolic syndrome. Potentiation of immunity is also a major function of G. lingzhi, and this has been applied in patients with cancer. Supplementing G. lingzhi into foods reduced the metastasis of cancer cells. β-l,3-glucan is an important bioactive component of G. lingzhi. In this study we enhanced the solubilization ofimmunostimulating β-l,3-glucan by autodigestion of G. lingzhi. Fruiting bodies of G. lingzhi were disrupted and suspended in distilled water, then autodigested at 37°C for 24 hours. The resulting suspension was dried by spray drying. To assess the solubilization of β-l,3-glucan by autodigestion, cold and hot water extracts and sodium hydroxide extracts of G. lingzhi were prepared with and without autodigestion. Sodium hydroxide extracts were neutralized and dialyzed against distilled water. The resulting soluble and precipitated fractions were collected. Chemical, biochemical, and immunochemical characteristics of the extracts were compared. The yields of cold water extracts of autodigested and native G. lingzhi were significantly lower than the other extracts. Glucose was the major sugar component of the hot water extract, cold alkali extract (CAS), and the cold hydroxide extract insoluble in neutral aqueous condition (CASP) of the autodigested and native G. lingzhi. Nuclear magnetic resonance analysis revealed branched β-glucans in the hot water extract and CAS of the autodigested and native G. lingzhi. By contrast, the CASP of the autodigested and native G. lingzhi comprised mainly mixtures of linear α-l,3-glucans and linear β-l,3-glucans. Immunostimulation by β-l,3-glucan was examined by limulus factor G activation, dectin-1 binding, and anti-β-glucan antibody binding. Comparing relative activity, immunostimulating β-l,3-glucan was detected in the hot water extract, rather than the CAS, of autodigested and native G. lingzhi. Immunostimulating of β-glucan was also detected in the cold water extract of the autodigested G. lingzhi. These findings demonstrate that autodigestion is a useful processing protocol for enhancing the usefulness of G. lingzhi as a functional food.