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Glycyrrhizic acid (GA) and glabridin (GD) are very important sweeteners and whitening agents present in Glycyrrhiza glabra L. This study investigates the cellulase and pectinase produced by endophytes in G. glabra to optimize and enhance the extraction of GA and GD from licorice using enzyme-assisted extraction (EAE) and microbial co-culture-assisted extraction (MCAE) approaches. Twelve strains with cellulase and pectinase activities were isolated from G. glabra. Notably, the strain G1–5, preliminarily identified as Penicillium sp., demonstrated superior performance in enzyme production and extraction efficiency of GA. Compared to the traditional extraction methods, the EAE process showed an obvious improvement of 32.21% and 56.37% in GA and GD extraction rates, respectively. Similarly, the MCAE process with the enzyme-producing strain G1–5 exhibited an increase of 25.52% and 38.45% in GA and GD extraction rates, respectively. These findings provide valuable guidance and innovative strategies for the extraction of active ingredients. [Display omitted] • Endophytic microbes and their enzymes in G. glabra were isolated and utilized. • A unique microbial co-culture-assisted extraction (MCAE) method was proposed. • Enzyme-assisted extraction (EAE) and MCAE are efficient extraction strategies. • The study provides a new and practical approach to improve bioactives extraction. [ABSTRACT FROM AUTHOR]

Pineapple leaves are agricultural waste but rich in the pineapple leaf fiber (PALF) with superior mechanical properties. The conventional PALF preparation usually include two steps of manual/mechanical extraction and chemical degumming, resulting in adverse issues such as fiber loss, inferior fiber quality, and environmental pollution. In the present study, a simplified and efficient preparation process of PALF, without any pretreatment and subsequent bleaching, was successfully achieved through in-situ inoculation of Bacillus subtilis XW-18 to fresh pineapple leaves. Results showed that B. subtilis XW-18 was rich in the diversified degumming-related enzymes, which could exert an direct retting and degumming action on the fresh pineapple leaves by simultaneously secreting high-activity pectinase, mannanase, and xylanase but low-activity cellulase. Due to the ideal combination of degumming-related enzymes in B. subtilis XW-18, the prepared PALF reached 2.29% of fiber yield and 3.50% of residual gum content, displaying a dispersed fibrous structure and white appearance. Structural characterizations and chemical compositions of PALF further confirmed that B. subtilis XW-18 had an effective action on removal of the non-cellulosic macromolecules such as gummy substances, hemicelluloses, and lignin, thus acquiring a high cellulose content up to 79.36 wt%. Furthermore, the method using in-situ inoculation of B. subtilis XW-18 achieved the prepared PALF with ideal physical and mechanical properties. In summary, B. subtilis XW-18 offered a promising alternative option for the green and efficient preparation of PALF, not only due to its one-step process for PALF preparation, but also due to its ideal combination of the degumming-related enzymes. [Display omitted] • Bacillus subtilis XW-18 produced an ideal combination of the retting and degumming enzymes. • Bacillus subtilis XW-18 prepared PALF without any pretreatment and subsequent bleaching. • The prepared PALF had a low residual gum content at 3.50% with a dispersed fibrous structure and white appearance. [ABSTRACT FROM AUTHOR]

Chinese water chestnut [ Eleocharis dulcis (Burm. f.) Trin. ex Hensch] peels (CWCPs) were a kind of vegetable waste and the present work was focusing on its comprehensive exploitation and utilization. Enzyme-assisted ultrasonic-microwave synergistic extraction (EAUMSE) of flavonoids from CWCPs was investigated, along with their qualitative and quantitative analysis using a combination of ultra-performance liquid chromatography-photodiode array (UPLC-PDA) and quadrupole-time-of-flight mass spectrometry (QTOF-MS). An optimal yield of 1.48% (w/w) was achieved with a 2:1 ratio (w/w) of cellulase and pectinase, 1.5% enzyme concentration, 5.0 pH, 50 °C hydrolysis temperature, 2 h hydrolysis time, with ethanol and 0.1 mol/L NaH 2 PO 4 buffer (2:1, v/v) mixture as solvent, ultrasound and microwave power was 50 and 200 W, respectively, and 60 s extraction time. The flavonoid yield by EAUMSE was 26.50%, 22.31% and 12.98% higher than that by solvent extraction (SE), ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE), respectively. Sixteen flavonoids were characterised, including four new ones, with the major flavonoids being luteolin (249 mg/100 g DW), eriodictyol (97 mg/100 g DW), 6-methylluteolin (74 mg/100 g DW) and fisetin (46 mg/100 g DW). The EAUMSE was an effective and green method for flavonoid extraction in the functional food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Microwave-assisted enzyme pretreatment followed by microwave hydrodistillation concatenated with liquid–liquid extraction (MEP-MHDE) was developed in this work for the efficient separation of essential oil from the leaves of Polygonum viscosum Buch-ham. The modified hydrodistillation concatenated with liquid–liquid extraction apparatus included conventional oil-water separation process and another extraction process for essential oil components from the hydrosol using an organic solvent. A comparison of the types of enzymes implied that the composite enzyme of cellulase and pectinase (1/1, w/w) performed better than the others. The optimum conditions derived were a microwave irradiation time of 17 min, a microwave irradiation power of 503 W, and an incubation temperature of 42 °C, which were evaluated through single factor experiments and Plackett–Burman design for selecting significant parameters as well as Box–Behnken design for optimizing the conditions. Based on these conditions, high yields of essential oil in the first separation column (3.66 ± 0.11 g/kg) and second separation column (1.02 ± 0.03 g/kg) were achieved. The developed MEP-MHDE method performed better regarding obtaining a higher yield of essential oil using a shorter time than other methods, which was mainly attributed to the influence of the combination of microwave irradiation, enzyme pretreatment and the hydrodistillation concatenated with liquid–liquid extraction apparatus. Through GC–MS analysis, more oxygenated compounds of the essential oil were achieved in the second separation column than in the first one, thus providing more valuable essential oil. Thus, the developed MEP-MHDE method is an efficient method for separation of high-value essential oils from natural plants and crops. [ABSTRACT FROM AUTHOR]

Distillers corn oil (DCO) is a valuable co-product of dry-grind corn ethanol process. It can be used for bio-fuel production and in animal feed. DCO can be present in different forms in the fermentation matrix, including oil adhering to solid surfaces such as cell wall and protein matrix, and oil contained in unbroken cells, which is difficult to partition to thin stillage by decanting. Effects of using surfactant (Tween ® 80) and enzymes during fermentation on DCO partition to thin stillage and DCO recovery from the condensed corn distillers with solubles (CCDS) were investigated. There was more than 8 ∼ 10% DCO adhered to wet cake solids in whole stillage produced by conventional procedure, and this part of DCO was moved to thin stillage when 500 ppm of Tween ® 80 was used during fermentation. Enzymes reduced the particle size of wet cake solids and released more DCO from wet cake to thin stillage. However, the use of protease reduced oil recovery (4.0% versus 7.9% and 17.9%, protease versus control and non-starch polysaccharide hydrolyzing enzymes) by producing partially hydrolyzed protein, which may have acted as emulsifier. Moreover, a synergistic effect between the use of enzymes and Tween ® 80 was found on DCO partition in thin stillage and its recovery from CCDS. [ABSTRACT FROM AUTHOR]

Cellulose conversion is the major step for the comprehensive utilization of potato residues. In potato residues, pectin is present in high amounts and tightly interlinked with cellulose, has an inhibitory effect on cellulose degradation, of which mechanism remain unclear. This study investigated inhibitory effects of pectin on the hydrolysis efficiency of cellulose in potato residue. The results showed that the soluble pectin had no significant inhibition and adsorption effect on cellulase activity, while the insoluble pectin had ineffective adsorption on cellulose. Moreover, insoluble pectin, attached to the surface of cellulose, showed an apparent physical barrier effect on the enzyme acting on the substrate. Pectinase addition efficiently degraded the insoluble pectin attached to the substrate surface and reduced the ineffective adsorption and physical barrier. After 5 U/g pectinase treatment, the enzymatic hydrolysis efficiency was improved by 30.68 %. Our study provides a promising approach for improving the utilization of potato residues. [Display omitted] • Pectin removal significantly enhanced cellulose degradation in potato residue. • Soluble pectin had no inhibitory effect on cellulase activity. • Insoluble pectin had a noticeable, non-productive adsorption effect on cellulase. • Insoluble pectin acted as a physical barrier in cellulase adsorption. [ABSTRACT FROM AUTHOR]

Sequential optimization strategy was used to enhance the production of extracellular polygalacturonase by a newly isolated Aspergillus fumigatus R6 using rice bran as a substrate in solid state conditions. Three significant variables influencing the polygalacturonase production were identified as initial moisture level, temperature and incubation time ( P < 0.0001). The model established by face-centered central composite design was significant ( P < 0.05) with high R 2 (0.98). The model validity was verified and the optimum conditions were at an initial moisture level of 49.6%, 33 °C and 129 h of incubation time with the maximum polygalacturonase activity of 565 U/g, resulted in 2.65 fold increase in polygalacturonase activity compare to the unoptimized conditions. Kenaf stem treated with A. fumigatus R6 polygalacturonase enzyme at 72 h produced high strength of kenaf bast fibers (287 MPa) with high Young’s modulus (10404 MPa) and the color is in satisfactory. [ABSTRACT FROM AUTHOR]

The potential for using pectinase as a pretreatment to improve the properties of hemp hurd for use in a hemp/polypropylene composite was compared with the addition of a silane coupling agent. Pectinase pre-treatment reduced pectin levels in the hemp hurd (p = 0.0014) and this reduction was associated with improved tensile strength, modulus of rupture, modulus of elasticity and resistance to water uptake (p < 0.0001). Pre-treatment had no consistent effect on thickness swell. Addition of a coupling agent to non-modified hemp/polypropylene panels produced similar improvements to panel properties (p < 0.0001) and also markedly reduced thickness swell (p = 0.01). The results indicate that pectinase pretreatment can enhance panel strength properties but did not affect moisture behaviour. [ABSTRACT FROM AUTHOR]

In this study, an improved method, enzyme-deep eutectic solvent pre-treatment followed by microwave-assisted hydrodistillation (EDP-MAHD), was applied to extract essential oil from the leaves of M. haplocalyx Briq. The synergistic effects of enzymatic hydrolysis, deep eutectic solvent, and microwave irradiation on the extraction kinetics and composition of essential oil were systematically evaluated. The yield of essential oil was improved under the pre-treatment conditions of mixed enzymes (cellulase and pectinase of 1:1) and choline chloride/glucose. By investigating the pre-treatment and microwave-assisted hydrodistillation processes, the yield of essential oil was enhanced to 2.19%. The results of GC-MS showed that menthol was the most important component in essential oil, with the content of 62.43%, and other components including menthone, piperitone, isomenthone, germacrene D, etc. Compared with other methods, EDP-MAHD could produce a higher yield of essential oil and make the essential oil have higher inhibitory activity on acetylcholinesterase and α-amylase (IC 50 value of 6.36 and 34.32 mg/mL, respectively). • Enzyme-deep eutectic solvent pretreatment promoted the extraction of essential oil. • Kinetic curve of essential oil was investigated and fitted by model. • Composition of essential oil under different conditions was analyzed. • Essential oil showed excellent inhibitory activity against AChE and α-amylase. [ABSTRACT FROM AUTHOR]

• Radio frequency-assisted enzymatic extraction was used to extract anthocyanins. • This extraction showed the highest crude yields and anthocyanin content over control. • Extracts had significant antioxidant and tyrosinas/α-amylase inhibitory activities. • Nine anthocyanins were firstly identified in Akebia trifoliata flowers. Anthocyanins are active compounds with various biological activities and are abundant in Akebia trifoliata (Thunb.) Koidz flowers. To extract anthocyanins from the flowers more effectively, a novel procedure of radio frequency heating-assisted enzymatic extraction was proposed in this study. The extraction conditions were optimized using Plackett-Burman and Box-Behnken design. The optimal extraction conditions were enzyme ratio of cellulase and pectinase of 1:1, enzyme concentration of 1.0 %, ethanol concentration of 50 %, liquid-solid ratio of 50 mL/g, pH of 4, and radio frequency pretreatment at 40 °C for 10 min with electrode gap of 5 cm. The results showed that radio frequency assisted enzyme extraction exhibited the highest crude yields (26.55 %) and anthocyanin content (50.87 mg cyanidin-3- O -glucoside equivalents/100 g) compared with hot water, acidified ethanol and enzymatic (pectinase and cellulase) assisted extractions. This method was effective for achieving high 1, 1-diphenyl-2-picrylhydrazyl radical scavenging activity (385.03 Trolox equivalents/g extract), reducing power (361.85 Trolox equivalents/g extract) and tyrosinase inhibitory (14.67 kojic acid equivalents/g extract) activity as well as significant α-amylase inhibitory activity. Nine anthocyanins were identified and did not detect any significant compound degradation using the novel approach. Accordingly, the proposed radio frequency and cellulase/pectinase combined extraction of anthocyanins was efficient and rapid. This method holds great promise for extracting bioactive compounds from plants and fruits. [ABSTRACT FROM AUTHOR]

• Material from cheap raw materials and cheap adhesive was produced. • Wheat and rapeseed straw particles were enzymatically treated. • Enzymatic treatment affected the properties of particles, but not the properties of boards. • The highest erosion of surface was reached via a combination of xylanases and pectinases. • No difference between the properties of wheat and rapeseed boards was observed. The paper deals with the possibility of using post-harvest crop residues, namely winter wheat straw and winter rapeseed straw for the purpose of producing particleboards. In order to increase particle surface energy, particles were treated with enzymes prior to application of the adhesive; xylanases, pectinase, and a combination of both. The effect of the enzymatic treatment on the properties of the treated particles was monitored and, after the production of the boards, the influence of particle treatment on the mechanical and physical properties of the composites was also monitored. The effect of enzymatic modification on the properties of wheat and rapeseed particles was observed. The enzymes used influenced the particle surface morphology, their surface energy and equilibrium moisture content. Only the combination of pectinase and xylanase (Texazym SER 7) increased the surface energy of wheat surface from 26 mN/m (untreated) to 30 mN/m. The greatest erosion of the surface was achieved by the combination of xylanases and pectinases. After enzymatic treatment both wheat and rapeseed straw exhibited higher equilibrium moisture content. The increase of moisture of wheat straw was from 11.9 %–13.2 % and of rapeseed straw from 12.4 %–13.44 %. Although the selected enzymes had an effect on the properties of the particles, the effect of the enzymatic treatment on the equilibrium moisture, the internal bond strength and the bending characteristics of the produced particleboards were not observed. Produced boards reached low mechanical properties, internal bond strength reached values form to 61–99 mN/mm2. [ABSTRACT FROM AUTHOR]