Although a promising method for lignin depolymerization, photocatalysis faces the challenge of low efficiency. In this study, MoS/ZnO heterojunction catalysts, endowed with piezocatalysis and photocatalytic capabilities, were crafted through Zn ion intercalation for the depolymerization of phenoxyphenylethanol (PP-ol) and alkali lignin. Then, the synergistic interplay between ultrasonic-induced piezoelectric fields and heterojunctions was analyzed.
View Article and Find Full Text PDFPolyphenols are the largest group of phytochemicals with important biological properties. Their presence in conveniently available low-cost sources, such as agri-food by-products, has gained considerable attention in their recovery and further exploitation. Retrieving polyphenols in a green and sustainable way is crucial.
View Article and Find Full Text PDFTo improve the antimicrobial ability of MoS-containing films, we used lignin and triple-frequency ultrasound for liquid-phase exfoliation (LPE) to obtain MoS nanosheets. Photoresponsive antimicrobial films with MoS nanosheets, lignin, polyvinyl alcohol and deep eutectic solvents were subsequently prepared. Lignin functionalized the MoS nanosheets by chemically linking with S in MoS and significantly improved the exfoliation efficiency.
View Article and Find Full Text PDFThe off-odors associated with spoilage of acidic beverages are linked to the germination and growth of Alicyclobacillus acidoterrestris (AAT) spores. As a consequence, we determined the influence of nutrients, non-nutrient germinants, dual-frequency thermosonication (DFTS), and food matrix on spore germination. AAT spores in orange juice (OJ), supplemented by L-alanine (L-ala), had the highest germination rate and lowest DPA content at 10 h of incubation.
View Article and Find Full Text PDFLignin has enormous potential as a renewable feedstock for depolymerizing to numerous high-value chemicals. However, lignin depolymerization is challenging owing to its recalcitrant, heterogenous, and limited water-soluble nature. From the standpoint of environmental friendliness and sustainability, enzymatic depolymerization of lignin is of great significance.
View Article and Find Full Text PDFLignin, an amorphous biomacromolecule abundantly distributed in the plant kingdom, has gained considerable attention due to its intrinsic bioactivities and renewable nature. Owing to its polyphenolic structure, lignin has a variety of human health activities, including antioxidant, antimicrobial, antidiabetic, antitumor, and other activities. The extraction of lignin from various sources in a green and sustainable manner is critical in the food industry.
View Article and Find Full Text PDFThe majority of acidic fruits are perishable owing to their high-water activity, which promotes microbial activity, thus exhibiting metabolic functions that cause spoilage. Along with sanitary practices, several treatments are used during processing and/or storage to inhibit the development of undesirable bacteria. To overcome the challenges caused by mild heat treatment, juice manufacturers have recently increased their involvement in developing novel non-thermal processing procedures.
View Article and Find Full Text PDFDiversiform okra dry powders were prepared and controlled-temperature ultrasonic-assisted extraction (CTUAE) was then utilized to obtain okra pectin (OP) from the preparative powders. During processing of hybrid techniques, 6 types of dry powders were prepared through different drying technologies (hot air drying, HD; freeze-drying, FD) and meshes (60, 80, 120 meshes) at first. Next, the extraction yield, physicochemical and function characteristics, and molecular structure of OP were analyzed with or without CTUAE technique.
View Article and Find Full Text PDFAlicyclobacillus acidoterrestris (AAT) was proposed as an index of pasteurization design for high-acid fruit products due to its spore resistance and repeated spoilage incidences in fruit juices. This study aimed to determine the effectiveness of pulsed multifrequency ultrasound to minimize AAT spores and vegetative cells in aqueous suspension. For this research, an investigation of the reactive oxygen species and antioxidant activity was performed to examine the effect of temperature and frequency on AAT spore inoculation.
View Article and Find Full Text PDFTo improve the soybean protein content (SPC), flavor and quality of soymilk, the effects of dual-frequency ultrasound at different angles (40 + 20 kHz 0°, 40 + 20 kHz 30°, 40 + 20 kHz 45°) on physicochemical properties and soybean protein (SP) structure of raw soymilk were mainly studied and compared with the conventional single-frequency (40 kHz, 20 kHz) ultrasound. Furthermore, the intensity of the ultrasonic field in real-time was monitored via the oscilloscope and spectrum analyzer. The results showed that 40 + 20 kHz 45° treatment significantly increased SPC.
View Article and Find Full Text PDFSoybean soaking is important to the processing of bean products, however, restricted by the long soaking time. Herein, the soybean soaking was assisted by 60 kHz sweeping frequency ultrasound (SFU). Shortening mechanism of soaking time and physicochemical properties of soybeans were analyzed.
View Article and Find Full Text PDFThis is the first time to investigate the synergistic inactivation effect and mechanism of multifrequency ultrasound (MTUS) on A. acidoterrestris (AAT) vegetative cells and spores, nutrients and enzymes of orange juice. The optimized results of MTUS (using Box Behnken design- surface responsemethodology) and further comparison with different mode of ultrasound (mono-and multi-frequency) revealed that 20/40 kHz, 24 min and 64 °C were the best optimum results.
View Article and Find Full Text PDFThe higher heating value (HHV) and exergy of ultrasound-assisted deep eutectic solvent pretreated watermelon rind (WMR) biomass were investigated. Thereafter, the co-pyrolysis of the WMR biomass and coal blends was studied. The pyrolysis kinetics and thermodynamic parameters of the WMR-coal blends were determined using four isoconversional models (Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, Friedman and Starink).
View Article and Find Full Text PDFSugarcane bagasse (SCB) is an abundant agricultural waste in China and the conversion of the waste into plethora of useful resources is very vital. To achieve this, fractionation of the waste is highly important in the biomass biorefinery. The present study aims at investigating the synergistic role of deep eutectic solvents (DES) with sweeping frequency ultrasound (SFUS) and fixed frequency ultrasound (FFUS) in the fractionation of SCB to enhance the enzymatic saccharification process.
View Article and Find Full Text PDFBackground: Ultrasonic pretreatment is a novel physical method that can be used in the extraction process of okra pectin. Real-time online monitoring technologies were introduced in time and frequency domains when okra was pretreated. Preparation time of dried okra and yield of okra pectin were studied; and physicochemical properties of okra pectin were analyzed at the optimum ultrasonic parameter.
View Article and Find Full Text PDFMild and effective pretreatments are essential to deconstruct lignocellulosic biomass so as to reuse cellulose content for value-added products. In this study, sequential multimode-ultrasound and microwave with natural ternary deep eutectic solvent (NATDES) pretreatments were used to deconstruct corn straw and optimized factors such as NATDES, ultrasonic, and microwave parameters. Results indicated that the ultrasound-NATDES or microwave-NATDES pretreatment could remove 37.
View Article and Find Full Text PDFUltrasound requires high power and longer treatment times to inactivate microorganisms when compared to ultrasound combined with other technologies. Also, the antimicrobial efficiency of aqueous ozone increases with an increase in its concentration and exposure time, but with a detrimental effect on the quality of the treated food. In this study, the effect of aqueous ozone at low concentration, multi-mode frequency irradiation and their combination on microbial safety and nutritional quality of cherry tomato was investigated.
View Article and Find Full Text PDFThe suitability of some non-linear kinetic models (Weibull {with or without tail}, Log-linear, Log-linear shoulder {with or without tail}, Biphasic linear, Logistic, Multi-target and Single-target models) were evaluated to determine the inactivation kinetics of inoculated E. coli, and natural microbiota (i.e.
View Article and Find Full Text PDFThe effects of moderate thermosonication (MTS) on the quality quartet: physico-chemical, microbial, nutritional and sensory qualities of orange juice (OJ) inoculated with Alicyclobacillus acidoterrestris (AAT) were studied during 24 days of storage at ambient and refrigerated temperatures. The bioactive compounds and antioxidant activity of OJ decreased with storage, while the pectin methyl esterase (PME) increased. Nonetheless, noticeable changes were observed from the 12th day of storage.
View Article and Find Full Text PDFBiochar properties are significantly influenced and controlled by biomass feedstock type and pyrolysis operating conditions, and the development of multiple biochar properties for various applications has necessitated the need for blending different feedstocks together. Co-pyrolysis as a potential technology has been proposed to improve the overall performance of biomass pyrolysis and has proved effective in improving biochar properties. Consequently, the combination of lignocellulosic and macroalgae biomasses has been targeted for biochar production and improvement of biochar properties through co-pyrolysis.
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