Food and Bioprocess Technology
·
2024
·
IF 5.3
Zhang Xu,Wang Rui,Zhang Wencong,Chen Cunkun,Ma Chao,Ji Ning,Zhang Nanxin,Lei Jiqing,Tian Yiming,Zhang Panpan
The shelf life of Dictyophora rubrovolvata ( D. rubrovolvata ) has been strongly limited by autolysis, a natural process of self-degradation. Conventional heat treatment methods (hot water or hot air) are not suitable for D. rubrovolvata fruiting bodies because of their fragile and porous structure. Therefore, in this work, we attempted to use microwave treatment (MT/100 W, 75 W, 50 W) to delay autolysis and extend the shelf life of D. rubrovolvata fruiting bodies. The results showed that MT could delay the decrease in cellulose, chitosan, and β-1,3 glucan contents by inhibiting the corresponding enzyme activity and maintaining a high level of energy charge by delaying the decrease in ATP and ADP. Meanwhile, compared with the control group (CK), D. rubrovolvata fruiting bodies after MT had improvements in many qualities during storage (4 °C, 95% RH), including delayed deterioration of water migration, sensory evaluation, browning, shear force, ethanol, malondialdehyde (MDA), relative conductivity, and respiratory rate. Furthermore, D. rubrovolvata fruiting bodies after MT maintained contents of umami compounds compared to CK, which included free amino acids, 5′-nucleotides, and equivalent umami concentration (EUC). The electronic nose (E-nose) results showed that MT maintained a better flavor. Notably, the effect of low power (50 W) was better than that of high power (100 W, 75 W). Thus, microwaves could effectively regulate autolysis and energy metabolism of D. rubrovolvata fruiting bodies during the postharvest period. Therefore, microwaves can be applied as a pretreatment method, providing valuable insights regarding postharvest mushrooms.
研究领域:
食品科学
·
微生物学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2020
·Vol. 56
·期 1
·441-451
·
IF 2.773
Geng Yang,Rui Wang,Jing-Rong Gao,Debao Niu,Jian Li,Qing-Hui Wen,Xin-An Zeng
Summary The effect of moderate pulsed electric fields (MPEF) strength on autolysis of Saccharomyces cerevisiae was evaluated in this study. After exposure to MPEF with intensity of 7 kV cm −1 for 4 ms, the integrity of the cell wall was obviously destroyed and the inactivation of S. cerevisiae reached 99.43%. During the subsequent 42-h autolysis process, the release of free α-amino nitrogen of MPEF-treated cells, as well as extracellular protease activity, was significantly ( P < 0.05) higher than that of untreated cells. Moreover, exposure to 7 kV cm −1 led to an increase of the total amino acid of 149.36%. In particular, the content of aspartic acid and glutamic acid which are important umami flavour precursors increased by 232.55% and 209.40%, respectively. These results indicate that MPEF will be an effective method to accelerate autolysis of S. cerevisiae for obtaining high-quality yeast extract as flavour enhancers and nutrition supplements.
研究领域:
食品科学
·
微生物学
✓ 已验证
DOI
高影响因子
BMC BIOTECHNOLOGY
·
2017
·Vol. 17
·期 1
·1-11
·
IF 2.415
Chang Fei,Zhang Xianbing,Pan Yu,Lu Youxue,Fang Wei,Fang Zemin,Xiao Yazhong
Background β-Glucosidase has attracted substantial attention in the scientific community because of its pivotal role in cellulose degradation, glycoside transformation and many other industrial processes. However, the tedious and costly expression and purification procedures have severely thwarted the industrial applications of β-glucosidase. Thus development of new strategies to express β-glucosidases with cost-effective and simple procedure to meet the increasing demands on enzymes for biocatalysis is of paramount importance.Results Light activated cassette YF1/FixJ and the SRRz lysis system were successfully constructed to produce Bgl1A(A24S/F297Y), a mutant β-glucosidase tolerant to both glucose and ethanol. By optimizing the parameters for light induction, Bgl1A(A24S/F297Y) activity reached 33.22 ± 2.0 U/mL and 249.92 ± 12.25 U/mL in 250-mL flask and 3-L fermentation tank, respectively, comparable to the controls of 34.02 ± 1.96 U/mL and 322.21 ± 10.16 U/mL under similar culture conditions with IPTG induction. To further simplify the production of our target protein, the SRRz lysis gene cassette from bacteriophage Lambda was introduced to trigger cell autolysis. As high as 84.53 ± 6.79% and 77.21 ± 4.79% of the total β-glucosidase were released into the lysate after cell autolysis in 250 mL flasks and 3-L scale fermentation with lactose as inducer of SRRz. In order to reduce the cost of protein purification, a cellulose-binding module (CBM) from Clostridium thermocellum was fused into the C-terminal of Bgl1A(A24S/F297Y) and cellulose was used as an economic material to adsorb the fusion enzyme from the lysate. The yield of the fusion protein could reach 92.20 ± 2.27% after one-hour adsorption at 25 °C.Conclusion sWe have developed an efficient and inexpensive way to produce β-glucosidase for potential industrial applications by using the combination of light induction, cell autolysis, and CBM purification strategy.
研究领域:
生物技术
·
酶工程
·
发酵工程
✓ 已验证
DOI
PubMed
高影响因子
Journal of Biomedical Nanotechnology
·
2018
·Vol. 14
·期 2
·389-395
·
IF 5.068
Shi Yang
The application of a peptide-based supramolecular hydrogel in the field of bioactive materials is limited by its poor stability in extreme environments. Increasing the number of hydrophobic amino acids in the peptides may enhance the stability of the hydrogel, but an organic solvent
is always required to dissolve peptides because of its strong hydrophobic properties. In this study, we linked hydrophilic amino acids to super hydrophobic peptides using a self-hydrolyzed ester bond as a linker to enhance its solubility in water, which resulted in two highly potent peptide
hydrogels. The hydrogels showed excellent stability in highly acidic, highly basic and saturated salt solutions for 15 days. This system may be particularly useful in designing a robust drug release system that can maintain a constant release rate for days and against abrupt changes in the
environment.
研究领域:
生物材料学
·
药剂学
✓ 已验证
DOI
PubMed
高影响因子
Small
·
2025
·
IF 12.1
Jiahao Zhang,Hongwang Tang,Hucheng Wang,Peiwen Cai,Yuliang Gao,Xuhong Guo,Yiming Wang,Fu-Zhen Xuan
Access to multifunction-integrated hydrogel microrobots is highly desired in many complex application scenarios, yet remains a challenging task. Here, adaptive out-of-equilibrium hydrogel microrobots exhibiting autonomous deformation, controllable autolysis, and directed locomotion in response to orchestrated chemical and physical signals are reported. These hydrogel microrobots are prepared by crosslinking carboxyl-decorated polymers through coumarin dimerization. Upon the addition of carbodiimide as a chemical fuel, the hydrophilic carboxyl groups are converted to hydrophobic anhydrides, leading to shrinking of the microrobots. However, with the depletion of fuel, the formed anhydrides spontaneously hydrolyze to the initial carboxyl groups, thus resulting in an autonomous swelling of the microrobots to their original size. Moreover, because of the efficient photocleavage of coumarin dimers, the microrobots can rapidly disintegrate (<10 min) upon irradiation. With the incorporation of magnetic powders, these hydrogel microrobots can be guided to move in space by a magnetic field. By virtue of these seamlessly integrated functions, the hydrogel microrobots can be manipulated to adaptively move through a narrow terrain and release the loaded cargo at a target position. This work may boost the development of multifunction-integrated lifelike soft robots for many complicated applications ranging from precision drug delivery to non-invasive therapies.
研究领域:
材料科学
·
生物医学工程
·
软体机器人
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2016
·
IF 2.529
Ru Song,Kai-qiang Zhang,Rong-bian Wei
Squid viscera, one of the major by-products in squid processing, were hydrolyzed to generate bioactive autolysates using their endogenous proteases. In vitro antioxidative activities of squid viscera autolysates (SVAs) were evaluated. The SVAs demonstrated strong activity on scavenging 1,1-diphenyl-2-picryl-hydrazil (DPPH) and hydroxyl radicals, as well as reducing power ability. The SVAs were purified using size exclusion chromatography and RP-HPLC. Nineteen peptides were identified in the active fraction SVAs3 by liquid chromatography-electrospray ionization/multi-stage mass spectrometry (LC-ESI-Q-TOF-MS/MS). Among these identified peptides, six peptides with relatively small molecular weights (700–800 Da), LLAPPER, FPGLADR, WVAPLK, FFNPVH, FNVVLK and LELPLK, were synthesized for assaying antioxidative activity in vitro. Peptide WVAPLK demonstrated strong scavenging effects on free radicals, with the IC 50 values of 0.82 ± 0.08 mg/mL (or 1.14 ± 0.11 mM) for DPPH radical and 1.85 ± 0.04 mg/mL (or 2.60 ± 0.06 mM) for hydroxyl radical, respectively. The low molecular weight and hydrophobic residue W at the N-terminus and basic residue K at the C-terminus as well as specific residues P and L within sequence should play a key role for the high antioxidative activity of WVAPLK. The results suggested that the SVAs could be used as a source of antioxidants and peptides.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Junjie Chen,Lifang Yang,Xuanwei Zhang,Yuelin Gu,Boya Su,Xiaohang Sun,Qiang Chen
The utilization of biomass-based hydrogels represents a versatile approach toward the conservation of waterlogged wooden artifacts, showcasing the potential of sustainable technologies in mild and long-term cultural relic treatments while simplifying preservation procedures to minimize environmental impact. Alginate/polyacrylamide hydrogels offer promising potential as substrate materials for conserving waterlogged wooden artifacts. Their robust mechanical properties and flexible functionality address specific preservation requirements, such as antimicrobial, moisturizing, and deacidifying needs, thereby enhancing the effectiveness and adaptability of conservation efforts. Herein, a self-dissolving hydrogel with antibacterial and deacidifying effects was prepared using silver nanoparticles (AgNPs) embedded in alginate/polyacrylamide hydrogels and used for the conservation of waterlogged archeological wood obtained from Nanhai No. 1, an 800-year-old shipwreck salvaged from the South China Sea. Its self-dissolving characteristics can effectively avoid damage to the wood when removing the hydrogel. The embedded AgNPs were found to provide a good preservation effect on wooden cultural relics in terms of solubility, stretchability, and antibacterial properties due to their tunable interaction with the polymer chains, which was characterized through scanning electron microscopy (SEM), gel permeation chromatography (GPC), mechanical testing, antibacterial experiments, etc. The gels can be stretched to 20 times their initial length and demonstrate a 99% reduction in bacterial presence. This innovative hydrogel effectively neutralizes the acid generated by bacteria metabolism and notably possesses self-dissolution behavior that avoids the damage caused by peeling off the hydrogel from the wood surface. These characteristics provide a distinct advantage for the timely protection and multipurpose preservation of wooden artifacts and offer potential in other comparable scenarios.
研究领域:
材料科学
·
文化遗产保护
·
纳米技术
·
高分子化学
·
考古学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FOOD SCIENCE
·
2016
·Vol. 81
·期 8
·C1883
·
IF 1.649
Ning Xu,Yaqi Liu,Yong Hu,Mengzhou Zhou,Chao Wang,Dongsheng Li
en The autolyzed mycelia of Aspergillus oryzae are rich in proteins, nucleic acids, sugar, and other biomacromolecules, and are one of the main contributors to the flavor profile of commercially important fermented goods, including soy sauce and miso. We induced autolysis of the mycelia of A. oryzae over 1 to 10 d, and found that the maximum dissolved amounts of total protein and nucleic acid ratio accounted for 28.63% and 88.93%, respectively. The organic acid content, such as citric acid, tartaric acid, succinic acid, lactic acid, and acetic acid, initially increased and then decreased as autolysis progressed, corresponding to changes in pH levels. The main characteristic flavor compounds in soy sauce, namely, ethanol, 2-phenylethanol, and 2-methoxy-4-vinylphenol, were all detected in the autolysate. Subsequently, we tested the effect of adding mycelia of A. oryzae during the fermentation process of soy sauce for 60 d, and found that addition of 1.2‰ A. oryzae mycelia provided the richest flavor. Overall, our findings suggest that compounds found in the autolysate of A. oryzae may promote the flavor compounds of soy sauce, such as alcohols, aldehydes, phenols, and esters. Practical Application pt Autolysate of Aspergillus oryzae mycelium contains rich nutrients and volatile flavor compounds, which is an important component of fermentation seasoning. This study provides a theoretical basis for developing the autolysate products of mycelia of A. oryzae and studying the flavor formation of soy sauce. The autolysate of A. oryzae may also be used to prepare healthy drinks and seasoning products.
研究领域:
食品科学
·
微生物学
·
风味化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2022
·
IF 5.895
Jinfang Zhang,Baoyue Zhu,Xiaojian Xu,Yihan Liu,Qinggang Li,Yu Li,Fuping Lu
Bacillus amyloliquefaciens has great potential as a host for heterologous protein production, but its severe autolytic behavior has precluded its industrial application to date. Because d,l-endopeptidase activity-guided cell wall rigidity is considered essential for autolysis resistance, we investigated the effects of d,l-endopeptidase genes lytE, lytF, cwlO, and cwlS play on the growth, lysis, and morphology remodeling of B. amyloliquefaciens strain TCCC11018. Individual and combinatorial deletion of lytE, lytF, and cwlS enhanced the cell growth and delayed cell lysis. For the best mutant with the lytF and cwlS double deletion, the viable cell number at 24 h increased by 11.90% and the cell wall thickness at 6 h increased by 25.87%. Transcriptomic and proteomic analyses indicated that the improvement was caused by enhanced peptidoglycan synthesis. With the lytF and cwlS double deletion, the extracellular green fluorescent protein and phospholipase D expression levels increased by 113 and 55.89%, respectively. This work broadens our understanding of the relationship between d,l-endopeptidases and B. amyloliquefaciens cell characteristics, which provides an effective strategy to improve the heterologous protein expression in B. amyloliquefaciens-based cell factories.
研究领域:
微生物学
·
生物技术
·
蛋白质工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD PROCESSING AND PRESERVATION
·
2020
·Vol. 44
·期 4
·e14383
·
IF 1.405
Zi-qiang Liu,Da-yong Zhou,Yu-xin Liu,Xiao-yang Liu,Yan Liu,Bing Liu,Liang Song,Fereidoon Shahidi
Matrix metalloprotease (MMP) is the key endogenous protease that boosts the autolysis of sea cucumber, while its action and mechanism in vivo are still unclear. MMP inhibitor (1,10-phenanthroline) was injected into coelomic cavity of sea cucumber ( Stichopus japonicus ) and its effects on autolysis and mechanism of action were investigated for the first time by using scanning electron microscopy, multi-functional in vivo imaging system, and confocal laser scanning microscopy. In response to external stimuli, the level of Ca 2+ in live sea cucumber dermis increased, which may activate MMP activity. MMP inhibitor could diffuse from coelomic cavity into body wall and significantly prevented the activation of MMP by chelating Ca 2+ , and thus, retarded the autolysis of fresh sea cucumber by preventing degradation of interfibrillar proteoglycan bridges between adjacent collagen fibrils. This work provides information toward understanding the mechanism behind the sea cucumber autolysis and demonstrate a potential approach to prevent the autolysis. Practical applications Autolysis occurs in sea cucumber in response to external stimulation. Matrix metalloproteinase (MMP) has been found to be the key endogenous protease that boosts the autolysis of sea cucumber body wall (SCBW). However, the role of MMP in the autolysis of SCBW in vivo and the mechanisms involved remain unclear. In this study, MMP inhibitor (1,10-phenanthroline) was injected into the body cavity of live sea cucumber, and its effects on in situ changes in SCBW were studied. Our results indicated that the activity of endogenous MMP in live SCBW was activated in response to external stimulation, which may be responsible for the autolysis. After injection into coelomic cavity, MMP inhibitor could diffuse into SCBW and significantly reduced the progress of typical morphological and microstructural changes of autolytic sea cucumber. Through chelating Ca 2+ , the MMP inhibitor could prevent the activation of MMP, and thus reduced the autolysis of fresh sea cucumber.
研究领域:
海洋生物学
·
生物化学
·
蛋白质组学
·
水产养殖
✓ 已验证
产品关联
DOI
高影响因子
Chinese Herbal Medicines
·
2023
·
IF 3.8
Yanshan Zhan,Xiaoqi Xu,Xi Luo,Ruiping Liu,Yujian Lin,Ping Zhao,Jun Shi
Objective Hypertrophic scars (HS) are a variety of skin tissue fibrosis disease that occurs in human skin, the effective therapeutic method of which is still inaccessible up to now. As a bioactive constituent of a well-known medical plant, Salvia miltiorrhiza (Danshen in Chinese), tanshinone II A (TSA) is reported to inhibit cell proliferation in HS. Therefore, the aim of this study was to prepare TSA self-soluble microneedles to strengthen its dermal retention and break through the difficulty of significantly thickening epidermal connective tissue and stratum corneum at the HS site. The possible mechanism of action in suppressing HS was studied using human skin fibroblasts (HSF). Methods Tanshinone II A self-dissolving microneedles (TSA-MN) was prepared using a negative mold casting method. The prescription process of microneedle was optimized by Box-Behnken effect surface method. Different media were selected to investigate the ability of transdermal absorption and in vitro release. Furthermore, according to Cell Counting Kit-8 (CCK8) method as well as the Western blot method, the effect of TSA-MN on the biological characteristics of HSF was investigated. Results With remarkable slow release effect and dermal retention, the release and transdermal properties of TSA-MN in vitro were better than both TSA and ordinary dosage forms. Its effect of HSF confirmed the essential decrease in cell motility during cell proliferation and cell migration in vitro , which plays a significant role in down-regulating the secretion of transforming growth factor- β 1 (TGF- β 1 ) in HSF and increasing the expression level of Smad7. Conclusion The prepared TSA self-soluble microneedles is helpful in solving the problem of hypertrophic scars, with a stable dermal retention effect after process optimization.
研究领域:
药学
·
皮肤病学
·
生物技术
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Microbiology
·
2023
·
IF 5.2
Zhao-xia Luo,Yuting Li,Mei-fang Liu,Rui Zhao
Staphylococcus aureus readily forms biofilms on host tissues and medical devices, enabling its persistence in chronic infections and resistance to antibiotic therapy. The accessory gene regulator (Agr) quorum sensing system plays a key role in regulating S. aureus biofilm formation. This study reveals the widely used fluoroquinolone antibiotic, ciprofloxacin, strongly stimulates biofilm formation in methicillin-resistant S. aureus , methicillin-sensitive S. aureus , and clinical isolates with diverse genetic backgrounds. Crystal violet staining indicated that ciprofloxacin induced a remarkable 12.46- to 15.19-fold increase in biofilm biomass. Confocal laser scanning microscopy revealed that ciprofloxacin induced denser biofilms. Phenotypic assays suggest that ciprofloxacin may enhance polysaccharide intercellular adhesin production, inhibit autolysis, and reduce proteolysis during the biofilm development, thus promoting initial adhesion and enhancing biofilm stability. Mechanistically, ciprofloxacin significantly alters the expression of various biofilm-related genes ( icaA , icaD , fnbA , fnbB , eap , emp ) and regulators ( agrA , saeR ). Gene knockout experiments revealed that deletion of agrC , rather than saeRS , abolishes the ciprofloxacin-induced enhancement of biofilm formation, underscoring the key role of agrC . Thermal shift assays showed ciprofloxacin binds purified AgrC protein, thereby inhibiting the Agr system. Molecular docking results further support the potential interaction between ciprofloxacin and AgrC. In summary, subinhibitory concentrations of ciprofloxacin stimulate S. aureus biofilm formation via an agrC -dependent pathway. This inductive effect may facilitate local infection establishment and bacterial persistence, ultimately leading to therapeutic failure.
研究领域:
微生物学
·
分子生物学
·
传染病学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）