Cellulase Pretreatment Research Articles

Enzymatic catalytic dynamics of lactic-acetic acid co-fermentation: Effect of cellulase on the physicochemical, phytochemicals, volatiles, and antioxidant activity of jujube puree extracts

The processing of jujube (Ziziphus jujuba) is imperative due to its esteemed status and rich pharmacological properties despite its sensory challenges and short shelf-life. Traditional drying methods preserve jujube quality but complicate bioactive compound extraction due to the conjugated polysaccharide matrix. This study addresses the gap in research on enzymatic pretreatment by investigating the use of cellulases to break down the rigid cellulose structure, thus enhancing the efficiency of subsequent fermentation processes. Besides, this research explored the catalytic dynamics of cellulase pretreatment in lactic-acetic acid co-fermentation to improve jujube puree's functional and quality properties. Methodologies involved applying cellulase at concentrations of 1 %, 3 %, and 5 % (v/v) at 40 °C for 4 hours, followed by fermentation with Lactobacillus plantarum CGMCC 3346 and Acetobacter pasteurianus (Ap CICC 20001, CGMCC 1.41). Results indicated that fermentation and enzyme hydrolysis significantly influenced jujube puree's physicochemical and sensory attributes. Fermentation increased densities and moisture content, while unfermented and enzyme-treated samples had higher total soluble solids (TSS) values (11.00–11.50 °Brix). Enzyme concentration affected the reducing sugar and protein content, with higher enzyme concentrations (5 %EF) producing lighter products (L* = 52.00). Total phenolic content increased with fermentation, particularly in the 3 %EF treatment (351.89 mg GAE/100 g FW), while flavonoid and flavonol contents peaked in the 5 %EF (426.33 mg RE/100 g FW) and 3 %EF (25.80 mg QE/100 g FW) treatments, respectively. Proanthocyanidin content was highest at moderate enzyme concentrations, notably in the 3 %EF treatment (715.95 mg CE/100 g FW). Fermentation also enhanced antioxidant properties and altered flavor profiles by decreasing acetoin levels and increasing acid and ester production. This study highlights the significance of the combinative effect of enzyme concentration and fermentation processes in augmenting jujube puree extracts' nutritional and sensory qualities.

Effect of exogenous cellulase pretreatment of straw-type fermented total mixed ration on digestibility and ruminal fermentation in growing beef cattle.

This study aimed to assess the impact of corn straw-based unfermented and fermented total mixed rations (TMR) supplemented with exogenous cellulase on the in vitro fermentation characteristics, growth performance, feeding behavior, apparent digestibility, rumen fermentation and digestive enzyme activities of Chinese Simmental bulls. Unfermented (direct spraying of exogenous cellulase onto TMR, TMR) and fermented (exogenous cellulase fermentation for more than 7 d, fermented total mixed rations [FTMR]) TMR were collected, dried, powdered and used as fermentation substrates. The fermentation liquid was ruminal fluid collected from Chinese Simmental bulls. The artificial rumen culture fluid were continuously cultured in vitro for 48 h. Based on the diets they were fed, 24 healthy Chinese Simmental bulls (average weight of 495.93 ±10.89 kg) were randomly divided into two groups, with 12 bulls in each group, which were fed TMR or FTMR. The study lasted 56 d. In in vitro experiments, the neutral detergent fiber degradability and total volatile fatty acid, propionate, iso-butyrate, iso-valerate and valerate concentrations were greater in the FTMR group (p<0.05) than in the TMR group. However, the methane production, pH and A/P of the FTMR group tended to be lower (p<0.05) than those of the TMR group. In the in vivo experiments, the average daily gain, eating rate, and feed efficiency of the FTMR groups were greater (p<0.05) than those of the TMR group. Similarly, the NDF degradability of the FTMR group was greater (p<0.05) than that of the TMR group. Compared to those in the TMR group, the concentrations of total volatile fatty acids, iso-butyrate, propionate and butyrate were greater in the FTMR group (p<0.05), and the A/P ratio was lower (p<0.05). Similarly, cellulase, xylanase, and β-glucosidase activities were greater (p<0.05) in the FTMR group than in the TMR group. Corn straw-based fermented total mixed rations supplemented with exogenous cellulase play a vital role in decreasing the structural carbohydrate content of TMR and ruminal methane production in vitro, improving nutrient digestion and absorption, optimizing rumen fermentation, and improving the growth performance of beef cattle.

Investigating the impact of ultrasound-assisted cellulase pretreatment on the nutrients, phytic acid, and phenolics bioaccessibility in sprouted brown rice

This study aimed to elucidate the impact of ultrasound-assisted cellulase (UC) pretreatment on nutrients, phytic acid, and the bioavailability of phenolics during brown rice sprouting. It sought to unveil the underlying mechanisms by quantifying the activity of key enzymes implicated in these processes. The sprouted brown rice (SBR) surface structure was harmed by the UC pretreatment, which also increased the amount of γ-oryzanol and antioxidant activity in the SBR. Concurrently, the UC pretreatment boosted the activity of phytase, glutamate decarboxylase, succinate semialdehyde dehydrogenase, Gamma-aminobutyric acid (GABA) transaminase, chalcone isomerase, and phenylalanine ammonia lyase, thereby decreasing the phytic acid content and increasing the GABA, flavonoid, and phenolic content in SBR. In addition, UC-pretreated SBR showed increased phenolic release and bioaccessibility during in vitro digestion when compared to the treated group. These findings might offer theoretical direction for using SBR to maximize value.

Cellulose degradation of cottonseed meal derived porous carbon for supercapacitor

Enzyme, as a type of biocatalyst, has a superior degradability on the biomass component. Herein, the cellulase degradation of cottonseed meal (CCM) is used as carbon source and potassium citrate as activating agent to fabricate O, S, N co-doped carbon materials. Cellulase pretreatment degrades the cellulose (from 12.48 wt% to 2.24 wt%) of cottonseed meal (CM) as well as creates the pore structure. Most importantly, the enzymolytic process can enhance the O content and improve the activation efficiency of potassium citrate. The optimized CCM-800-2 with hierarchical porous structure and high O (11.33 at%) content exhibits a high specific capacitance of 364 F g-1 in 6 M KOH electrolyte. In addition, the assembled potassium citrate-chitosan gel electrolyte-based symmetric supercapacitor with 20 mg cm-2 mass loading of active material shows a high energy density of 28.8 Wh kg-1. This study provides an efficient enzyme assisted pretreatment and low activator ratio strategy to prepare biomass-based porous carbon, and expects to fabricate more carbon materials using other carbon precursors.

Effect of Pretreatments on the Production of Biogas from Castor Waste by Anaerobic Digestion

Lignocellulosic biomass is a source of carbohydrates that can be used in the production of biogas. The aim of this study was to obtain biogas from biomass waste (leaves, stems and seed bagasse) of Ricinus communis, applying pretreatments such as temperature and humidity. We examined the effect of these pretreatments on the biomass, two enzymatic pretreatments (cellulase and cellobiohydrolase), two chemicals (NaOH and HCl) and two controls (dried castor straw and seed bagasse) on the methane content. The experiment was performed in two anaerobic digestion (AD) assays at a controlled temperature (37 °C) and at room temperature, with a hydraulic retention time (HRT) of 55 days. The results showed that the residues of the seed bagasse produced the highest biogas yields both at room temperature and at the controlled temperature since this material at 37 °C produced 460.63 mL gVS−1 under cellulase pretreatment; at room temperature, the highest level of production was found for the control (263.41 mL gVS−1). The lowest yields at the controlled temperature and room temperature were obtained from residues of Ricinus communis treated with cellobiohydrolase and the seed bagasse treated with alkaline (15.15 mL gVS−1 and 78.51 mL gVS−1, respectively). Meanwhile, the greatest amount of methane was produced by seed bagasse treated with cellobiohydrolase at a controlled temperature (92.2% CH4) and the lowest content of CH4 (15.5%) was obtained at a controlled temperature from castor straw under the control treatment.

Pré-tratamentos enzimáticos para melhorar o processo de secagem de beterraba

Abstract The objective of this work was to evaluate the use of cellulase and pectinase as pretreatments for the drying of beetroot (Beta vulgaris). The experiment consisted of slices of beetroots subjected to four different treatments before the drying procedure, as follows: no wet pretreatment; wet pretreatment without enzymes; pectinase solution pretreatment; and cellulase solution pretreatment. Treatments were compared for drying rates, color change, content of betalains, and plant tissue structure. A modified Page model was used to describe the drying process. The enzymatic pretreatments did not improve the drying kinetics, although they changed the plant tissue structure. A negative influence on the drying was observed when pectinase was used; however, no effect was observed when cellulase was used. Slices treated with cellulase remained unchanged for color. Slices treated with pectinase showed significant changes of color, in comparison with the control treatments. The enzymatic pretreatments studied did not change the betalain concentrations and showed similar drying performance in the comparison with control treatments. Cellulase pretreatment is promising because it does not change the beetroot color or the betalain concentration.

Ultrasound-assisted cellulase pretreatment and cooking with enzymatic hydrolysates enhance the freeze-thaw stability of brown rice

Brown rice (BR) is rich in nutrients and becoming a good source for convenience rice development. However, the bran layer of BR and freeze-thawing in food supply chains affects the rice texture and limits the palatability. This study aims to apply the preprocessing method of ultrasound-assisted cellulase (UAC) that has been demonstrated to improve the textural attributes of BR, and further make use of the enzymatic hydrolysates for rice cooking, to stabilize the texture against freeze-thawing. BR with cellulase pretreatment and addition of the enzymatic hydrolysates during cooking exhibited stable hardness and stickiness over five freeze-thaw cycles as compared to the rice cooked with water or the diluted hydrolysates. As observed by scanning electron microscopy and low-field nuclear magnetic resonance, BR cooked with the hydrolysates displayed more homogenous microstructure and the reduced water mobility against freeze-thawing, revealing that sugar and proteins in the hydrolysates contributed to promote the water holding capacity of cooked rice. Moreover, BR cooked with the hydrolysates exhibit noted advantages in fiber (0.23 g/kg) and proteins (0.19 g/kg) content. The combination of UAC pretreatment and cooking with the enzymatic hydrolysates provides a promising processing method for convenience brown rice with improved freeze-thaw stability and nutritional quality.

Evaluation of the In Vitro Bioactivities’ Profiles of Brewers’ Spent Grain Protein and Hydrolysates with and without Cellulase Pretreatment

Brewer’s spent grain is the residue left after the separation of wort during the beer-brewing process. Although this by-product has been reported to have a high protein content, it is normally treated as waste. This work aims to isolate bioactive hydrolysates from BSG, and then explore their bioactivities. Two groups (A and B) of BSG were subjected to protein extraction using the alkaline extraction method at pH 12, where group A was pre-treated with cellulase, while group B was not pre-treated and was directly extracted. The final isolate yielded 50.18 ± 1.22% recovery of the BSGP from group A and 66.41 ± 0.37% recovery from group B. RP-HPLC profiles showed that the extracted BSGPs are mainly hydrophilic proteins. The proteins extracted by the two methods were hydrolyzed enzymatically using Alcalase and α-chymotrypsin. The hydrolysates obtained displayed blood pressure regulation activity and antioxidant properties, when assayed with angiotensin-converting enzyme assay, 2,2-diphenyl-picryl-hydrazyl assay, and ferric antioxidant power assay. It can be concluded that it is possible to extract good quality proteins from BSG and this by-product presents potential as a source for the extraction of a variety of proteins that might be of interest to the food industries.

Ultrasonic-Assisted Efficient Extraction of Coumarins from Peucedanum decursivum (Miq.) Maxim Using Deep Eutectic Solvents Combined with an Enzyme Pretreatment.

In this study, the ultrasonic-assisted extraction of total coumarins from Peucedanum decursivum (Miq.) Maxim (P. decursivum) via the combination of deep eutectic solvents (DESs) with cellulase pretreatment was carried out. Among the 15 kinds of DESs with choline chloride as hydrogen bond acceptors, the DES system of choline chloride/1,4-butanediol with a molar ratio of 1:4 showed the best extraction effect. First, single-factor experiments were performed using the following factors: liquid–solid ratio, pH, enzyme dosage and ultrasonic temperature. The Box–Behnken design (BBD) and response surface methodology (RSM) were employed to optimize the extraction conditions and obtain the following optimal parameter values for the extraction of coumarins from P. decursivum: liquid–solid ratio 14:1 mL/g, pH 5.0, enzyme dosage 0.2%, ultrasonic temperature 60 °C and ultrasonic time 50 min. Under these conditions, the extraction yield of total coumarins from P. decursivum could reach 2.65%, which was close to the predicted extraction yield of 2.68%. Furthermore, the contents of six coumarins, namely, umbelliferone, nodakenin, xanthotoxin, bergapten, imperatorin and decursin were determined to be 0.707 mg·g−1, 0.085 mg·g−1, 1.651 mg·g−1, 2.806 mg·g−1, 0.570 mg·g−1 and 0.449 mg·g−1, respectively, using HPLC-MS after the optimization. In addition, the cell fragmentation of P. decursivum powder obtained using ultrasonic-assisted DES extraction with enzyme pretreatment was found to be the most comprehensive using scanning electron microscopy (SEM), which indicated the highest extraction efficiency for P. decursivum. Finally, the in vitro antioxidant activity of the extracts was evaluated via radical scavenging with 1,1-diphenyl-2-picrylhydrazyl (DPPH), which showed that ultrasonic-assisted DES extraction with enzyme pretreatment exhibited significant antioxidant activity with DPPH radical scavenging of up to 97.90%. This work developed a new and efficient extraction method for coumarins.

Cellulase pretreated palm decanter cake for feeding of black soldier fly larvae in triggering bioaccumulation of protein and lipid into biodiesel productions

For every ton of palm oil produced, approximately 0.2 tons of palm decanter cake (PDC) waste is generated. Hence, there is a huge opportunity to valorize this organic waste, i.e., via the deployment of black soldier fly larvae (BSFL), which has been widely employed to convert various organic wastes into larval proteins and lipids. However, the PDC is mainly made up of lignocellulosic materials that are hard to digest by the BSFL. Therefore, this work attempted to grow BSFL in cellulase-pretreated PDC; thereby, providing an alternative solution to manage PDC waste. Results had shown that the cellulase pretreatment was effective in breaking down cellulose into glucose molecules, especially with higher cellulase dosage and longer treatment duration of up until 48 h. Subsequently, the maximum BSFL growth was found at 6.56 ± 2.69 mg/larva when being fed with PDC pre-treated by 1.0 wt% of cellulase for 72 h; which was about 4 mg higher than the controlled larva. Using a similar substrate, the highest protein yield and lipid yield from BSFL were attained at 1.63 ± 0.11 mg/larva (22.4 wt%) and 5.12 ± 1.01 mg/larva (69.9 wt%), respectively. In terms of biodiesel quality, a huge presence of saturated fatty acids had made the BSFL-based biodiesel oxidatively stable.

Evaluation of Nannochloropsis gaditana raw and hydrolysed biomass at low inclusion level as dietary functional additive for gilthead seabream (Sparus aurata) juveniles

Abundant research is being carried out in the last years aimed at exploring microalgal biomass as nutrient source for different species of aquacultured fish. Some microalgae species, such as Nannochloropsis gaditana, have thick cell walls rich in cellulose, which might well reduce the bioavailability of intracellular active compounds. Among the alternatives aimed at overcoming this limitation, cellulase enzyme hydrolysis is proposed as a convenient and practical solution. In this regard, an in vitro assay was carried out, in which N. gaditana biomass was treated with cellulase (5% w/w basis) and the release of soluble compounds (reducing sugars, free amino acids and total phenolics) into the reaction medium was measured and compared to untreated raw biomass. The results confirmed increased yields of those compounds as a result of the enzyme pre-treatment. A 90-d feeding trial was also carried out in order to assess in vivo the influence of the inclusion of N. gaditana in feeds on juvenile gilthead seabream (Sparus aurata) growth, digestive physiology and body composition. Microalgal biomass was added at two inclusion levels (25 and 50 g kg−1 dry weight) in four experimental feeds, either crude or enzymatically pre-treated. Animals (15.1 g initial body weight) were randomly assigned to five dietary treatments (two inclusion levels, 2.5 and 5%, and two microalgae formats, raw and enzymatically hydrolysed, plus a microalgae-free control), and distributed triplicate tanks per dietary treatment. Fish were withdrawn after 45 and 90 days, and proximate composition, muscle fatty acid and amino acid profiles, muscle and liver lipid oxidation, instrumental skin colour, digestive enzyme activities, as well as structural and ultrastructural changes in the intestinal mucosa were determined. No differences attributable to the dietary treatments were found with regard to fish growth or proximate composition at the end of the feeding trial. On the contrary, the inclusion of microalgal biomass, irrespectively of the cellulase pre-treatment, caused beneficial effects on some physiological parameters (namely digestive mucosa structure and functionality, oxidative status of muscle lipids, and instrumental colour). The only clear improvement found in fish attributable to the cellulase pre-treatment of the microalgal biomass was related to the prevention of muscle lipid oxidation. Overall, the results suggest that N. gaditana used as additive (at inclusion level below 5%) in feeds might represent a valuable nutritional strategy for S. aurata juveniles, even if growth was not affected.

Research on the electrochemistry synergied cellulase enzymes strengthens the anaerobic fermentation of cow dung.

Lignocellulose degradation (LCD) was the key factor limiting the development of anaerobic fermentation (AF) by the cow dung (CD). In the research, the effects of cellulase pretreatment (CP) and microvoltage (MV) alone and combination on the gas production and LCD during the AF were investigated. The results showed that both CP and MV had an significant effect on the AF, though the synergistic reaction was more pronounced. The total biogas yield (TBY) could reach 11521mL, and the highest methane production rate was 73% in the synergistic reactions, which was increased by 18.7% and 10.0% compared to CP and MV alone respectively. Meanwhile, the degradation rates of cellulose and lignin could be increased by 33.44% and 22.23%, respectively. The results of SEM, FT-IR and excitation emission matrix demonstrated that CP and MV played an important role in improving the fermentation efficiency. The microbial biomass change results indicated that the synergistic effect of CP and 0.8V MV on the LCD was achieved by promoting the growth of lignocellulose-degrading bacteria. Moreover, the electricity could not only accelerate the movement of microorganisms and enzymes, but also promoted and enhanced the activity of enzymes, which provided an important reference for further development of the AF technology and the biogas industry.

Combining Fiber Enzymatic Pretreatments and Coupling Agents to Improve Physical and Mechanical Properties of Hemp Hurd/Wood/Polypropylene Composite.

Natural fiber/plastic composites combine the low density and excellent mechanical properties of the natural fiber with the flexibility and moisture resistance of the plastic to create materials tailored to specific applications in theory. Wood/plastic composites (WPC) are the most common products, but many other fibers are being explored for this purpose. Among the more common is hemp hurd. Natural fibers are hydrophilic materials and plastics are hydrophobic, therefore one problem with all of these products is the limited ability of the fiber to interact with the plastic to create a true composite. Thus, compatibilizers are often added to enhance interactions, but fiber pretreatments may also help improve compatibility. The effects of pectinase or cellulase pretreatment of wood/hemp fiber mixtures in combination with coupling agents were evaluated in polypropylene panels. Pretreatments with pectinase or cellulase were associated with reduced thickness swell (TS24h) as well as increased modulus of rupture and modulus of elasticity. Incorporation of 5.0% silane or 2.5% silane/2.5% titanate as a coupling agent further improved pectinase-treated panel properties, but was associated with diminished properties in cellulase treated fibers. Combinations of enzymatic pretreatment and coupling agents enhanced fiber/plastic interactions and improved flexural properties, but the effects varied with the enzyme or coupling agent employed. The results illustrate the potential for enhancing fiber/plastic interactions to produce improved composites.

Enhancing cellulose nanofibrillation of eucalyptus Kraft pulp by combining enzymatic and mechanical pretreatments

Nanofibrillated cellulose (NFC) extracted from biomass has potential applications in material science and biomedical engineering. In this study, NFC was obtained from bleached eucalyptus Kraft pulp (BEKP) using two commercial enzyme cocktails with cellulolytic and hemicellulolytic activities and non-catalytic protein (swollenin), followed by ultrasonication. This work represents an initial study of the implementation of non-catalytic proteins along with enzymes to extract NFC from biomass. Enzymatic pretreatment was performed to partially remove hemicellulose while enhancing cellulose accessibility for NFC extraction. Cellulase pretreatment with xylanase and swollenin supplementation increased cellulose accessibility and fiber swelling due to extensive hemicellulose removal (> 80%) and fiber morphology changes. Subsequent ultrasonication was performed for cellulose nanofibrillation resulting in high NFC yields (61–97%), while keeping NFC properties almost unchanged. Through this process, cellulose nanofibers with diameters ranging from 3 nm to 10 nm were effectively isolated from BEKP, which allows to produce high quality NFC for further applications.

Optimization of pretreating poplar wood shavings with cellulase to produce binderless fiberboard using response surface methodology

Wood processing waste, poplar wood shavings, were used for fiberboard production, and the pretreatment conditions using cellulase were studied using response surface methodology (RSM). After single factors optimization, central level of temperature, dosage, and liquid/solid ratio (LSR) of cellulase pretreatment conditions were obtained. Further optimization to study the influence of the factors was carried out using Box-Behnken design of experiments. A second-order polynomial equation was obtained, and the low p-value (&lt;0.007) implied that the model was highly significant by analysis of variance (ANOVA). The optimized cellulase pretreatment conditions for maximum bending strength (BS) of the fiberboard were determined by ridge analysis as 44.4 °C of temperature, 1.23 U/g of dosage, 4.2 of LSR, and 5 h of pretreatment time. Under the optimized conditions, the BS of the fiberboard reached 25.12 ± 0.35 MPa by validation experiment, which was twice that of the fiberboard without pretreatment. Thus, the cellulase pretreatment should be a good choice to produce high-strength binderless fiberboard.

Impacts of Cellulase and Amylase on Enzymatic Hydrolysis and Methane Production in the Anaerobic Digestion of Corn Straw

The impacts of enzyme pre-treatments on anaerobic digestion of lignocellulosic biomass were explored by using corn straw as a substrate for enzyme pre-treatment and anaerobic digestion and by utilizing starch and microcrystalline cellulose as substrates for comparative analysis. The cellulase pre-treatment effectively improved the enzymatic hydrolysis of cellulose, decreased the crystallinity, and consequently showed 33.2% increase in methane yield. The methane yield of starch increased by 16.0% through amylase pre-treatment. However, when the substrate was corn straw, both the efficiencies of enzymes and methane production were markedly reduced by the lignocellulosic structure. The corn straw’s methane yields were 277.6 and 242.4 mL·CH4/g·VS with cellulase and amylase pre-treatment, respectively, which was 11.7% and 27.9% higher than that of the untreated corn straw. It may imply that the lignocellulose should be broken up firstly, enzyme pre-treatments could have great potentials when combined with other methods.

Evaluation of the effect of feruloyl esterase-producing Lactobacillus plantarum and cellulase pretreatments on lignocellulosic degradation and cellulose conversion of co-ensiled corn stalk and potato pulp

The effects of feruloyl esterase-producing Lactobacillus plantarum A1, cellulase, or their combination on the fermentation characteristics, carbohydrate composition, and enzymatic hydrolysis of mixed corn stalk and potato pulp silage were investigated. Two mixture ratios were used: a weight ratio of rehydrated corn stalk to potato pulp of 35:1 (HD) and a weight ratio of dry corn stalk to potato pulp of 5:11 (LD). No advantage was observed with the addition of strain A1 alone for lignocellulosic degradation and cellulose conversion, while its combination with cellulase enhanced the lignocellulosic degradation and preserved more fermentable carbohydrates in co-ensiled corn stalk and potato pulp. The enzymatic hydrolysis results indicated a potential benefit of pretreatment for biogas production, as the co-ensiled HD ratio mixture without additive treatment showed high glucose yield after enzymatic hydrolysis following 60 d of fermentation.

Effect of Ultrasound and Cellulase Pre-treatment on the Water Distribution, Physical Properties, and Nutritional Components of Lentinula edodes Chips

This study aimed to understand the effect of ultrasound pre-treatment (UP), cellulase pre-treatment (CP) and their combination (UP+CP) pre-treatments on freeze-dried Lentinula edodes chips. The water distribution, microstructure, physical properties (colour, texture and shrinkage) and the main nutritional components (polysaccharides, protein and phenolic compounds) were investigated. The low-field nuclear magnetic resonance spectroscopy results showed that UP+CP improved the water mobility and level in mushroom slices. The chips subjected to UP+CP were found to have no free water. In addition, compared with other pre-treatment, UP+CP chips achieved better physical properties, which were characterized by the texture, colour and pore structures. All these attributors could contribute to a rapidly water transfer and improve the crisp characteristics. However, no significant difference was found in three pre-treatment products in polysaccharide and protein contents, though UP+CP products obtained higher phenolic content. Overall, the application of UP+CP was a potential pre-treatment approach for improving the quality of mushroom chips.

Influence of enzyme-aided extraction and ultrasonication on the phenolics content and antioxidant activity of Paeonia officinalis L. petals

Peony is a less utilized herbaceous plant of ornamental and medicinal relevance. The petals are rich in bioactive phenolics and hence, the development of efficient extraction is required for maximum recovery and bioactivity. In this study, the optimal conditions for the ultrasound-assisted extraction of peony phenolics were first investigated by comparing to conventional extraction and testing the data fit by mathematical models (linear, two factor interactions, quadratic) followed by investigation of cellulase pre-treatment combined with ultrasonication. High amounts of flavonoids, phenolics and tannins were extracted in 30 min under ultrasound conditions of 150 W, 40 kHz, 50 % amplitude, in 70 % ethanol with 50/1 solvent/solid ratio. A further cellulase pre-treatment at 40 ?C for different incubation times combined with ultrasonication facilitated the extraction of anthocyanins (720.48 mg/100 g DW), phenolics (3985.50 mg/100 g DW), flavonoids (2369.28 mg/100 g DW) and tannins (8917.81 mg/100 g DW). Good antioxidant activities by FRAP (350.03 mg ascorbic acid/100 g DW) and DPPH (inhibition values &gt;80 %) were registered showing great potential for developing high-value bioingredients. The FTIR analysis revealed the presence of characteristic functional groups. The hereby- -combined extraction methods could be extended to other peony species.

Combination of xylanase and cellulase hydrolysis for enhanced saccharification of poplar chips: Process optimization

Removing xylan from the outer surface of cellulose could promote the accessibility of cellulase to cellulose. Under this premise, in order to develop an efficient pretreatment method to obtain fermentable reducing sugar from poplar fiber, a response surface methodology was created via the combination of the Plackett-Burman design and the Box-Behnken design and was utilized by the Design-Expert software. The optimum conditions were as follows: a liquid-solid ratio of 4.95 to 1 (mL/g), a pre-hydrolysis xylanase temperature of 70.3 °C, and a total hydrolysis time of cellulase of 52.9 h. Under these conditions, the maximum amount of reducing sugars converted from poplar fiber was 159.6 mg/g. The average amount from the validation results was 160.1 mg/g, which was in agreement with the predicted value. Meanwhile, the poplar fiber hydrolyzed via a xylanase-aided two-stage pretreatment was compared with the poplar fiber hydrolyzed via only a cellulase pretreatment, using scanning electron microscopy. The xylanase-aided treatment revealed a surface with a more damaged structure, indicating that the utilization of xylanase could further improve the effects of hydrolysis on poplar fibers.