Foods
·
2023
·Vol. 12
·期 18
·3420
·
IF 5.2
Minyu Cai,Liyan Huang,Sashuang Dong,Nanxin Diao,Weilian Ye,Zhiye Peng,Xiang Fang
Summer green tea (SGT) has a low cost and high annual yield, but its utilization rate is limited due to suboptimal quality. The aim of this study is to enhance the flavor of SGT using fermentation withA. nigerRAF106 while examining changes in its metabolites during this process. The results revealed an elevation in the content of alcohol, alkanes, and nitroxides in tea leaves following the process of fermentation. The predominant volatile compounds identified in tea leaves after undergoing a 6-day fermentation period were linalool, (Z)-α, α, 5-trimethyl-5-vinyltetrahydrofuran-2-methanol, (E)-linalool oxide (furan type), linalool oxide (pyran type), and theapyrrole. These compounds exhibited significant increases of 31.48%, 230.43%, 225.12%, 70.71%, and 521.62%, respectively, compared to the non-fermented control group (CK). The content of non-ester catechins, soluble sugars, and total flavonoids reached their peak on the 4th day of fermentation, exhibiting significant increases of 114.8%, 95.59%, and 54.70%, respectively. The content of gallic acid and free amino acids reached their peak on the 6th day of fermentation, exhibiting significant increases of 3775% and 18.18%, respectively. However, the content of ester catechin decreased by 81.23%, while caffeine decreased by 7.46%. The content of lactic acid, acetic acid, and citric acid in tea after fermentation was 421.03%, 203.13%, and 544.39% higher than before fermentation, respectively. The present study offers a fresh approach for the advancement of SGT.Keywords:summer green tea;Aspergillus niger;fermentation;flavor
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CONTROL
·
2015
·
IF 2.806
Yanzhen Wang,Xiaobin Zeng,Zhengkun Zhou,Ke Xing,Akalate Tessema,Hong Zeng,Jun Tian
The antifungal activity of Nerol (NEL) was evaluated against Aspergillus niger , a known cause of grape spoilage, and possible modes of action were explored. The antifungal efficacy of NEL against A. niger has been proven in a dose-dependent manner through in vitro (mycelial growth and spore germination) and in vivo (grapes) tests. An obvious increase in the membrane permeability was detected through the determination of extracellular pH and conductivity. The damage in the cell membrane was measured by monitoring the influx of Propidium iodide (PI) using flow cytometry and was further verified through the inhibition of ergosterol synthesis in the cell membrane. NEL induced morphological changes, and the integrity of the A. niger fungal cells decreased with increasing NEL concentrations. A dose-dependent decrease in ergosterol production was also seen in A. niger cell membranes upon exposure to NEL. The mechanism-of-action study revealed that NEL activated a membrane-active mechanism that inhibits ergosterol synthesis and consequently compromised the membrane integrity of A. niger . As a result, the membrane permeability changes and causes cell death. The membrane lesion mechanism makes NEL a natural alternative to commercial fungicide for control of stored grape spoilage.
研究领域:
食品科学
·
微生物学
✓ 已验证
DOI
高影响因子
FOOD CONTROL
·
2024
·
IF 5.6
Lihui Zhang,Jialing Zhu,Shaojin Wang,Long Chen,Zihan Song,Lei Zhang,Haile Ma
Effectively controlling molds in dried shiitake mushrooms is important for food industry to maintain the product quality. To improve the edible safety of shiitake mushrooms, this study applied radio frequency (RF) energy combined with natamycin to inactivate Aspergillus niger spores, and evaluate the quality changes after the treatment. The results showed that the population of A. niger spores in shiitake mushrooms with different moisture contents (MCs) could achieve a 5-log (CFU/g) reduction after the combined treatment at different temperatures. Weibull distribution ( R 2 = 0.978 to 1.000) provided a better fit for the inactivation kinetics of A. niger spores than Linear model ( R 2 = 0.954 to 0.990) and Logistic one ( R 2 = 0.953 to 0.988). Meanwhile, the three-dimensional inactivation curves were constructed based on the sample MCs, RF heating time, and holding time. In addition, the MCs of treated shiitake mushrooms decreased by 4.12%–7.66% (w.b.) after natural cooling, achieving synchronous drying. There was no significant difference in textural properties of shiitake mushrooms after the combined treatment. The changes in color, structure, rehydration ratio, and total sugar content were affected by the treatment time and temperatures. As one of the main aroma substances, the content of sulfur-containing compounds in shiitake mushrooms after treatment increased compared to that of the control samples. This study indicates that the combination of RF energy and natamycin is feasible for inactivating pathogens in shiitake mushroom and ensuring the safety of their consumption.
研究领域:
食品科学
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
Fermentation-Basel
·
2023
·Vol. 9
·期 1
·50
·
IF 3.7
Zhen Fan,Tianming Chen,Guolin Cai,Xiaoyu Huang,Suchuan Zhong,Xiaoming Li,Enping Zhang
Fermentation has been considered as an effective means to improve the feed nutrient digestibility of corn stalks, and it is beneficial to animal growth performance and health. The beneficial functions of fermented corn stalks are related to the variety of metabolites produced through fermentation, but the nature of these components is still unclear. In this study, gas chromatography–mass spectrometry, combined with principal component analysis and partial least squares discriminant analysis, was used to explore the differential metabolites of corn stalks before and afterAspergillus nigerfermentation. A total of 32 potential characteristic compounds were obtained, mainly including sugar and glycoside derivatives, organic acids and their derivatives, alcohol compounds, benzene and its substituted derivatives, amino acids, phenolic compounds, and flavonoids. Compared with the metabolites in corn straw before fermentation, the relative content of D-threitol, mannitol-1-phosphate, coniferin, citrazinic, oxoglutaric acid, chenodeoxycholic acid, naproxen, 5-aminovaleric acid, vanillin, catechin, and UDP-glucuronic acid was significantly increased, and the relative content ofN-acetylgalactosamine, heneicosanoic acid, chlorogenic acid, and adenosine was significantly decreased. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that 20 metabolic pathways corresponded to the differential characteristic metabolites. The results of this study will provide theoretical support for the quality evaluation of fermented corn stalks and high-value product development in the future.Keywords:Aspergillus niger;fermentation;metabolomics;corn straw;metabolites
研究领域:
微生物学
·
动物营养学
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产品关联
DOI
高影响因子
Toxins
·
2014
·Vol. 6
·期 11
·3157-3172
·
IF 2.48
Wei Zhang,Beibei Xue,Mengmeng Li,Yang Mu,Zhihui Chen,Jianping Li,Anshan Shan
Aflatoxin B1, a type of highly toxic mycotoxin produced by some species belonging to theAspergillusgenus, such asAspergillus flavusandAspergillus parasiticus, is widely distributed in feed matrices. Here, coumarin was used as the sole carbon source to screen microorganism strains that were isolated from types of feed ingredients. Only one isolate (ND-1) was able to degrade aflatoxin B1after screening. ND-1 isolate, identified as a strain ofAspergillus nigerusing phylogenetic analysis on the basis of 18S rDNA, could remove 26.3% of aflatoxin B1after 48 h of fermentation in nutrient broth (NB). Optimization of fermentation conditions for aflatoxin B1degradation by selectedAspergillus nigerwas also performed. These results showed that 58.2% of aflatoxin B1was degraded after 24 h of culture under the optimal fermentation conditions. The aflatoxin B1degradation activity ofAspergillus nigersupernatant was significantly stronger than cells and cell extracts. Furthermore, effects of temperature, heat treatment, pH, and metal ions on aflatoxin B1degradation by the supernatant were examined. Results indicated that aflatoxin B1degradation ofAspergillus nigeris enzymatic and this process occurs in the extracellular environment.Keywords:Aspergillus niger;coumarin;aflatoxin B1;degradation
研究领域:
微生物学
·
毒理学
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食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMEDICAL AND ENVIRONMENTAL SCIENCES
·
2019
·
IF 1.917
Zhi Na YIN,Wen Jia WU,Chong Zhen SUN,Hui Fan LIU,Wen Bo CHEN,Qi Ping ZHAN,Zhuo Gui LEI,Xuan XIN,Juan Juan MA,Kun YAO,Tian MIN,Meng Meng ZHANG,Hui WU
Objective A strain of Aspergillus niger ( A. niger ), capable of releasing bound phenolic acids from wheat bran, was isolated. This strain was identified by gene sequence identification. The antioxidant and anti-inflammatory capacity of ferulic acid released from wheat bran by this A. niger strain (FA-WB) were evaluated. Methods Molecular identification techniques based on PCR analysis of specific genomic sequences were conducted; antioxidant ability was examined using oxygen radical absorbance capacity (ORAC), cellular antioxidant activity (CAA) assays, and erythrocyte hemolysis assays. RAW264.7 cells were used as a model to detect anti-inflammatory activity. Results The filamentous fungal isolate was identified to be A. niger . ORAC and CAA assay showed that FA-WB had better antioxidant activity than that of the ferulic acid standard. The erythrocyte hemolysis assay results suggested that FA-WB could attenuate AAPH-induced oxidative stress through inhibition of reactive oxy gen species (ROS) generation. FA-WB could significantly restore the AAPH-induced increase in intracellular antioxidant enzyme activities to normal levels as well as inhibit the intracellular malondialdehyde formation. TNF-α, IL-6, and NO levels indicated that FA-WB can inhibit the inflammation induced by lipopolysaccharide (LPS). Conclusion Ferulic acid released from wheat bran by a new strain of A. niger had good anti-inflammatory activity and better antioxidant ability than standard ferulic acid.
研究领域:
食品科学
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微生物学
·
营养学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2020
·
IF 2.952
Jianfeng Mei,Xiaoyun Zhao,Yu Yi,Yanlu Zhang,Xudong Wang,Guoqing Ying
Natural astaxanthin is widely used as a food and cosmetics additive because of its multiple biological activities. However, astaxanthin produced by Haematococcus pluvialis is generally esterified, and its activity is far less than that of free astaxanthin. Hydrolysis of astaxanthin esters to free astaxanthin by enzymes can overcome the drawbacks of chemical saponification methods. In this paper, a slug-flow microchannel reactor was constructed and tested in enzymatic hydrolysis of astaxanthin esters. The reactor consists of a “T” slug-flow generator, a stainless-steel microchannel, two constant-flow pumps, and a temperature controller. The reactor has the advantages of simple configuration and easy scale-up, and is suitable for two-phase biochemical reactions. Using the microchannel reactor, astaxanthin esters in H. pluvialis oil were efficiently hydrolyzed to free astaxanthin by lipase from Aspergillus niger . After hydrolysis, the content of free astaxanthin in H. pluvialis oil was 18.8 mg/L, 7.83-times higher than that before hydrolysis (2.13 mg/L). The hydrolysis rate reached 75.4 %. These results indicate that the microchannel reactor can be useful for the production of free astaxanthin from its esters.
研究领域:
生物化学
·
食品科学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Microbiology
·
2022
·
IF 6.064
Youqiang Xu,Huiqin Huang,Hongyun Lu,Mengqin Wu,Mengwei Lin,Chunsheng Zhang,Zhigang Zhao,Weiwei Li,Chengnan Zhang,Xiuting Li,Baoguo Sun
Fatty acid ethyl esters are important flavor chemicals in strong-flavor baijiu. Microorganisms are the main contributors to ester synthesis during baijiu manufacture. However, the ester synthesis was unstable between batches. This was owing to a limited knowledge of the mechanisms for ester synthesis by microorganisms. In this work, a fatty acid ethyl ester synthesizing Aspergillus niger strain CGMCC (China General Microbiological Culture Collection) 3.4309 was identified. The conversion ratios of ethyl valerate, ethyl caproate, ethyl caprylate, and ethyl caprate were 7.87, 29.20, 94.80, and 85.20%, respectively, under the optimized conditions. A comparison of transcriptomes under the initial and optimized ester synthetic conditions indicated that 23 genes were upregulated in transcription level and encoded enzymes with potential abilities for ester synthesis. Eleven of the enzymes were expressed, and three of them, numbered An605, An1097, and An3131, showed the ability to catalyze fatty acid ethyl ester synthesis under aqueous phase, with capric acid as the preferred substrate. The possible enzymatic catalytic mechanism was proposed based on homology modeling and molecular docking. This study reported for the first time that A. niger showed the ability to efficiently catalyze the synthesis of short- and medium-chain fatty acid ethyl esters in aqueous phase, identified the key enzymes, and analyzed the basic enzymatic properties. This is helpful to promote the application of related microorganisms and enzyme resources in the baijiu industry.
研究领域:
微生物学
·
生物化学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RESOURCES CONSERVATION AND RECYCLING
·
2019
·
IF 7.044
Jiaying Cui,Nengwu Zhu,Yao Li,Deliang Luo,Pingxiao Wu,Zhi Dang
The current researches on the recycling of waste liquid crystal displays (LCDs) are hard to widely industrialize that require low-cost, rapid and green technologies . In this study, we shortened the acetone soaking time from at least 20 h to 30 min to separate polarizer . In addition, indium bioleaching using Aspergillus niger ( A. niger ) was firstly explored. The efficiency of indium bioleaching from fermentation broth could reach 100% within 90 min at 70 °C, and the glass residues could be reused. Oxalic acid showed excellent abilities on indium bioleaching process according to the analysis of Fourier transform infrared spectroscopy and kinetics. Furthermore, the leaching parameters of low-concentration oxalic acid solution were optimized using response surface method to improve the powder dosage from 10 to 150 g/L. Therefore, this research promoted bioleaching technology development using A. niger and formed a sustainable process in industry for the recovery of valuable materials from waste LCDs.
研究领域:
环境科学
·
生物技术
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Yuhan Xia,Bolun Zhang,Ziyu Guo,Shanshan Tang,Yingjie Su,Xiaoxiao Yu,Siji Chen,Guang Chen
In this study, fungal mycelium ( Aspergillus niger and Myrothecium verrucaria ) were used to prepare modified hierarchical porous carbons through a simple way, that is, the fungal mycelium were added to the medium and the composite materials were formed by combining the growth characteristics of the microorganism with agar. After carbonization and activation process, the obtained Aspergillus niger -agar hierarchical porous carbon (HCAAN, 4343.3 m 2 g −1 ) and Myrothecium verrucaria -agar hierarchical porous carbon (HCAMV, 3520.1 m 2 g −1 ) have ultra-high specific surface area. While the synthetic dye brilliant green (BG) and antibiotic tetracycline hydrochloride (THC) were used as organic pollutants models, the maximum adsorption capacities of HCAAN and HCAMV for BG were 3364.34 and 3144.56 mg g −1 , and for THC were 1441.29 and 1279.21 mg g −1 , respectively. This study proved that the modification of fungal mycelium could indeed improve the performances of the composite materials, and more importantly, it provided a new strategy for the exploration of other microbial composites.
研究领域:
环境科学
·
材料科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CONTROL
·
2014
·
IF 2.819
Chunmei Jiang,Junling Shi,Xianqing Chen,Yanlin Liu
Fungal profiles and ochratoxin A (OTA) accumulation during wine making were investigated using five different wine grape cultivars, Cabernet Sauvignon, Pinot Noir, Merlot, Syrah and Petit Verdot and the intrinsic influences caused by sulfur dioxide, ethanol and combine effect of ethanol and reducing sugar were analyzed using Cabernet Sauvignon and inoculation of Aspergillus carbonarius . Aspergillus spp. and Penicillium spp. were found as the major fungi in all winemaking processes and were highly correlated with OTA accumulation in wine. Most fungi died and OTA production decreased after 48 h of alcoholic fermentation , being consistent with the period when ethanol accumulation increased. The addition of SO 2 significantly inhibited the growth and OTA production of A. carbonarius with complete inhibition at 500 mg/L. When the ethanol concentration in the must increased to the range of 2–4%, growth and OTA production of A. carbonarius were significantly inhibited. Reducing sugar concentration had no significant effect on the growth and OTA production of A. carbonarius within the levels changing during the winemaking. Therefore, the increase of ethanol concentration played an important role in causing the decrease of fungal contamination and OTA accumulation during winemaking.
研究领域:
食品微生物学
·
真菌毒素学
·
酿酒科学
·
食品安全
·
应用微生物学
·
分子毒理学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Qi Sun,Jianmei Li,Ying Sun,Qiao Chen,Lei Zhang,Tao Le
Cinnamaldehyde (CIN) is a promising replacement for chemical synthetic preservatives, which has exhibited effective antimicrobial activities in food applications. In this study we examined the antifungal efficiency of CIN against Aspergillus niger in vitro . In addition, we explored its mode of action and evaluated its application potential in bread preservation in situ . The results showed that CIN exerted different levels of antifungal activity through different treatments, wherein it showed the highest antifungal activity in the liquid broth test, followed by solid contact and gas diffusion methods. On the other hand, ultrastructure observation, propyl iodide staining and ergosterol detection showed that CIN may damage the cell ultrastructure and membrane integrity in a dose dependent manner. Besides, the content of reactive oxygen species and malondialdehyde were, respectively, 2.74 and 2.07 times higher in fungi treated with 100 μg/mL of CIN, compared with those in untreated fungi. Finally, shelf life experiment showed that, in the vapor phase, CIN can efficiently prolong the shelf life of bread. Altogether, these results indicate that CIN can be used as an alternative food preservative due to its antifungal effects that are exerted, at least in part in A. niger , through the induction of oxidative stress, which caused cell damage and increased membrane permeability.
研究领域:
食品科学
·
微生物学
·
保鲜技术
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）