Food Chemistry Commons^™

Allosteric And Uncompetitive Inhibition Of Yeast Alcohol Dehydrogenase Identified By Enzyme Kinetics, Dylan Jeremy Harrison, Jenny A. Cappuccio

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Enzyme kinetics is a powerful technique used to quantify the rate at which an enzyme converts a substrate into a product and to identify potential inhibitors. In this study, kinetic analysis was employed to assess the activity of yeast alcohol dehydrogenase (YADH) in the presence and absence of sweeteners commonly found in alcoholic beverages. YADH catalyzes the oxidation of ethanol to acetaldehyde using NAD⁺ as a cofactor; the reduction to NADH can be monitored spectrophotometrically at 340 nm. Based on structural similarities to the ribose moiety of NAD⁺, it was hypothesized that sucrose and sucralose could directly interact with the …

Phytochemical Composition And Bioactivities Of Roselle (Hibiscus Sabdariffa L.) Extracts Obtained By Infusion, Ethanolic Maceration, And Maltodextrin-Assisted Drying, Risna Silvianti, Warsito Warsito, Elok Zubaidah, Zubaidah Ningsih, Aqidatul Izza

Karbala International Journal of Modern Science

Roselle (Hibiscus sabdariffa L.) is rich in phenolic compounds and anthocyanins, but the extraction method may influence its chemical composition and biological activity. This study compared hot-water infusion, ethanolic maceration, and maltodextrin-assisted drying. It aimed to examine the relationship between the extraction method, chemical profile, and bioactivity. The resulting extracts (EI, EM, and EP) were analyzed for total phenolic, flavonoid, and anthocyanin, LC-HRMS profiles, and antioxidant capacity by the FRAP assay. Antibacterial analysis was conducted against Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) using agar well diffusion. Cytotoxicity tests (MTT, 24 h) were performed against HT-29, 4T1, …

Spectroscopic Characterization And Extraction Optimization Of Catechins In Green Tea, Zach J. Mckinley, Masakatsu Watanabe

SACAD: Scholarly Activities

This research initiative immerses students in a multifaceted analytical chemistry investigation of catechins—polyphenolic antioxidants prevalent in green tea—through the application of both classical and modern techniques. The project emphasizes hands-on experience with real-world sample analysis, method development, and critical data interpretation.

Catechins were extracted from various commercial green tea products, including loose leaves, powders, and dietary supplements, by trituration with ethyl acetate followed by solvent partitioning using a methanol and water solution. The resulting extracts were analyzed using UV-Visible spectroscopy to quantify catechin content. Selected samples were further characterized by liquid chromatography–mass spectrometry (LC-MS), confirming both the identity and purity …

Research Progress In Antagonistic Bacteria Against Staphylococcus Aureus, Caiqi Wang, Yuansong Ma, Xinrui Zhao, Pei Zhou, Sifan Lu, Yuxin Li, Yinbiao Xu

Journal of Food Science and Biotechnology

Staphylococcus aureus,a common Gram-positive foodborne pathogen,is ubiquitous in the human skin and respiratory tract.It can cause pneumonia,pleurisy,endocarditis,food poisoning,sepsis and other infectious diseases.The widespread and long-term use of antibiotics has aggravated the antibiotic resistance of Staphylococcus aureus.In particular,the emergence of multi-drug resistant strains has greatly reduced the therapeutic effect.Therefore,developing new antibacterial means to replace or assist existing antibiotics has become an urgent need.Microbial natural products are important resources for the development of new antibiotics,and antagonistic microorganisms play an important role.This paper reviewed the species of antagonistic bacteria against Staphylococcus aureus,the types of antibacterial active substances,and the commonly used screening methods of …

Probiotics Regulate Gut Microbiota And Immune Homeostasis To Prevent And Treat Food Allergy : A Review, Yao Chen, Zumeng Xia, Yijin Yang, Lianzhong Ai, Guangqiang Wang, Yan Zhang, Zhen Luo, Yong Zhou, Yongjun Xia

Journal of Food Science and Biotechnology

Food allergy (FA) is a common immunological disorder,and its pathogenesis is primarily associated with a complex regulatory process involving CD 4+ T cells in the immune system,such as the polarization of Th 2 cells and the imbalance between Treg/Th 17 cells.The balance of intestinal immune cells plays a critical role in the development of FA,while dysbiosis of the gut microbiota may disrupt this balance,thereby contributing to the onset of FA.Probiotic intervention targeting the gut microbiota can directly or indirectly influence the functions of immune cells to regulate immune responses,representing a promising approach for the prevention and treatment of FA.The authors …

Research Progress Of Gc-Ms-Based Metabolomics In Fermented Cereal Foods, Haichen Liu, Chang Liu, Hongyan Huo, Hui Xu, Shunxi Zhu, Lei Liu, Kui Zou

Journal of Food Science and Biotechnology

As an emerging discipline,metabolomics has gradually become the focus of food science research.Among numerous metabolomics analysis methods,gas chromatography-mass spectrometry (GC-MS ) has attracted much attention for its wide application.Fermented cereal foods occupy an important position in global dietary culture and are an indispensable type of foods in peopl e’s daily lives.The author reviewed the application of GC-MS based metabolomics for the development of fermented cereal foods,covering sample preparation,metabolite extraction,data analysis,and practical application in fermented cereal foods.Moreover,this paper elaborated on the advantages and limitations of GC-MS-based metabolomics in fermentation,aiming to provide a reference for further exploring the principles of food fermentation …

Mechanism Of The Effect Of Microwave Heating On The Degradation Of Fructans In Steamed Cakes Prepared With Saccharomyces Cerevisiae, Xiaoyue Ying, Yuan Tao, Yuan Yuan, Ziting Li, Bowen Yan, Jianxin Zhao, Wei Chen, Daming Fan

Journal of Food Science and Biotechnology

[Objective ] This study aimed to investigate the effect of microwave heating on the fructan mass fraction in steamed cakes prepared with Saccharomyces cerevisiae and elucidate the molecular mechanism of the activation of invertase by microwave.[Method ] Steamed cakes were prepared under varying microwave power density (3.40~5.10 W/g ) and heating time (2~5 min ),and the fructan mass fraction was compared between steamed cakes prepared by microwave heating and conventional steaming.The activity of invertase from Saccharomyces cerevisiae was measured under microwave heating and water bath heating conditions.Molecular dynamics simulations were performed to explore the invertase-kestose interactions under microwave fields.[Result ] …

Differences In Important Chemical Components And Free Radical Scavenging Activities Of The Ginger Germplasm Resources From Fujian, Meichun Chen, Enquan Lin, Xuefang Zheng, Zuliang Li, Bo Liu, Jieping Wang

Journal of Food Science and Biotechnology

[Objective ] This study aims to analyze the important chemical components of different ginger germplasm resources from Fujian and evaluate their comprehensive quality and free radical scavenging activities.[Method ] Gas chromatography-mass spectrometry (GC-MS ) and liquid chromatography-quadrupole-time of flight-mass spectrometry (LC-QTOF-MS ) were employed to determine the importance chemical components in 13 ginger germplasm resources.Differences in the chemical compounds were analyzed by the cluster analysis and principal component analysis (PCA ).The free radical scavenging activities of the ginger germplasm resources against ABTS+ were further evaluated.[Result ] A total of 65 chemical compounds were identified from the 13 ginger germplasm resources,including …

Cyanidin- 3-Glucoside Ameliorates Ocular Surface Dysfunction In Rats With Dry Eye Disease, Ke Zhang, Ziyu Liu, Zhangben Yao, Peng Zhang, Lei Tian, Ying Jie, Yong Wang

Journal of Food Science and Biotechnology

[Objective ] Studies have shown that cyanidin- 3-glucoside (C3G),the main component of black rice anthocyanins,exhibits protective effects on retina and retinal pigment epithelium (RPE ) cells.However,there is a lack of in vivo evidence regarding the efficacy of C 3G in alleviating dry eye disease (DED ),which limits its application in ocular surface disorders.This study aims to investigate the protective effects of C 3G on DED in rats.[Method ] 24 Wistar rats were randomly assigned into control,model,and C 3G groups.In model and C 3G groups,a DED model was established by subcutaneous injection of scopolamine hydrobromide (4 times daily for 28 d).The …

Analysis Of Polyphenol Composition And Antioxidant Activity Of Jujube Juice Fermented By Lactic Acid Bacteria By In Vitro Simulated Gastrointestinal Digestion, Jiangning Zhang, Zheng Ye, Jiaqi Shen

Journal of Food Science and Biotechnology

[Objective ] This study aims to investigate the variation rules of polyphenolic substances and antioxidant activity of jujube juice fermented by lactic acid bacteria after in vitro simulated gastrointestinal digestion.[Method ] The mass fractions of total phenols,free phenols,and bound phenols,as well as the composition of polyphenolic substances and antioxidant activity in the jujube juice fermented by lactic acid bacteria (original jujube juice ) at different fermentation stages and in vitro simulated gastrointestinal digestive fluids were determined and compared.[Result ] With prolonged fermentation time,the mass fractions of total phenolics in the original jujube juice and the gastric digestive fluid increased and …

Influences Of Different Withering Methods On The Quality Of Wuyi Rock Tea Produced From Rain-Soaked Leaves, Chengjiang Wei, Weijiang Sun, Zhechen Han, Peng Zhang, Weiwei Wu, Tao Wang, Qinglan Chen, Qi Lin, Jie Xu, Fuming Lin

Journal of Food Science and Biotechnology

[Objective ] This study aims to investigate the effects of different withering methods on the quality of Wuyi rock tea produced from rain-soaked leaves.[Method ] The rain-soaked leaves of Wuyi Shuixian (Camellia sinensis ) were treated with three withering methods:comprehensive withering in a fermentation machine,natural withering,and withering in an automated withering equipment.Sensory evaluation,biochemical component detection,and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry were employed to comparatively analyze the flavor compounds.[Result ] The tea samples processed by the automated withering equipment (PW) exhibited the highest overall quality,characterized by a rich floral and fruity aroma,as well as a mellow,brisk,and refreshing taste.Cluster …

Ultrasound-Assisted Enzymatic Transformation And Immune Efficacy Of Black Ginseng Saponins, Kuo Wang, Bao Zhong, Mingran Luan, Fenglin Li, Zhongkui Lu, Guanran Wang, Kun Yao

Journal of Food Science and Biotechnology

[Objective ] This study aims to elucidate the transformation process of black ginseng saponins and their immunomodulatory mechanisms.[Method ] An ultrasound-assisted enzymatic method was employed for the transformation of black ginseng saponins,and the mass concentration of black ginseng saponins was determined.Furthermore,the immunomodulatory effects of black ginseng saponins were investigated through animal experiments.[Result ] Under the conditions of an enzymatic hydrolysis temperature of 40 ℃,an enzyme mass fraction of 8%,enzymatic hydrolysis time of 60 min,and ultrasonic treatment time of 25 min,the mass concentration of black ginseng saponins increased from 1 615.40 μg/mL to 3 351.38 μg/mL,which represented an increase of 107.47%.The …

Degradation Of Nutrients In Corn Steep Liquor By Aspergillus Oryzae And Absorption Characteristics Of The Product, Xiaojie Wang, Chunrong Xia, Xiaolan Liu

Journal of Food Science and Biotechnology

[Objective ] This study aims to explore the degradation patterns of nutrients in corn steep liquor by Aspergillus oryzae and the absorption characteristics of the product.[Method ] Aspergillus oryzae was used for the fermentation of corn steep liquor,and degradation patterns of nutrients were studied after fermentation for 1,3,5,7,9,and 11 d.Changes in amino acid mass fraction and peptide molecular mass distribution in corn steep liquor after fermentation for 7 d were measured.Furthermore,the resting cells of Auricularia heimuer mycelia were used to explore the absorption characteristics of the fermentation product of corn steep liquor.[Result ] As the fermentation time prolonged within 1~7 …

Screening And Identification Of Strains Of Lactic Acid Bacteria For Fermentation From Suancai In The Dai Ethnic Region Of Yunnan, Rui Wang, Jiawen Zhang, Lianqin Zhang, Xian Chen, Yan Chen, Cheng Zuo, Lixin Li, Yuhua Diao

Journal of Food Science and Biotechnology

[Objective ] This study aims to screen the strains of lactic acid bacteria (LAB ) suitable for Suancai fermentation.[Method ] Traditional fermented Suancai from the Dai ethnic region of Yunnan was used as the research samples for the isolation and purification of LAB.The purified isolates were evaluated for fermentation characteristics,including nitrite degradation,acid production,acid resistance,and salt tolerance.Additionally,the antimicrobial activity,antibiotic susceptibility,hemolytic activity,and amino acid decarboxylase activity were assessed to identify dominant strains.[Result ] A total of 208 LAB strains were isolated from 40 Suancai samples.Preliminary screening based on nitrite degradation identified 20 strains with high efficiency,and 16S rDNA sequencing identified 15 strains …

Antioxidant And Anti-Fatigue Properties Of Malus Spectabilis Fruit Polysaccharides In Mice, Zhilin Wen, Ming Li

Journal of Food Science and Biotechnology

[Objective ] This study aimed to explore the antioxidant and anti-fatigue properties of Malus spectabilis fruit polysaccharides (MPPs ) and analyze the structure-activity relationships.[Method ] Two types of MPPs were prepared via acidic (AC-MPC ) and alkaline (AL-MPC ) extraction methods.The polysaccharide composition was identified by high-performance anion-exchange chromatography (HPAEC ).The changes in mouse body mass,serum biochemical indicators,and exhaustive swimming time were measured to assess the in vivo antioxidant and anti-fatigue effects of MPPs.[Result ] Galacturonic acid was the main component in both types of MMPs,while AL-MPC had higher mass fraction of total polysaccharides.The in vivo experiments demonstrated that both …

Ultrasound-Assisted Dual-Enzyme Extraction Condition Optimization And Antioxidant Activity Evaluation Of Anthocyanins From Perilla Leaves, Wenting Zhu, Shiyun Wang, Qiaolin Zhu, Qi Cao, Yixin Zhang, Tianran Hong

Journal of Food Science and Biotechnology

[Objective ] This study aims to comprehensively develop perilla and improve its utilization value.[Method ] Using perilla leaves as raw material,the effects of solid-liquid ratio,ethanol volume fraction,ultrasonic time,and enzymatic hydrolysis time on the mass fraction of anthocyanins in perilla leaves were studied.The ultrasound-assisted dual-enzyme extraction conditions for anthocyanins from perilla leaves were optimized by the response surface method.The antioxidant activity and phenol mass fraction of anthocyanins from perilla leaves were determined,and the main phenols were analyzed by chromatography.[Result ] The optimal extraction conditions of anthocyanins from perilla leaves were solid-liquid ratio of 1 g∶16 mL,ethanol volume fraction of 74%,ultrasonic time …

Immobilization Of Pseudomonas Fluorescens Lipase Onto Chitosan And Chitin-Based Carriers And Evaluation Of Its Hydrolytic Performance, Haoyu Zhong, Hongyu Qin, Jun Zhang, Kuntai Li, Qiuyu Xia, Shucheng Liu

Journal of Food Science and Biotechnology

[Objective ] This study aims to construct chitosan and chitin-based carriers with hierarchical porous lamellar structures,systematically evaluate the immobilization effects of these carriers for Pseudomonas fluorescens lipase (PFL) and the performance of the immobilized enzyme in catalyzing the hydrolysis of fish oil.[Method ] Chitin/chitosan were modified via the sol-gel method to prepare the carriers for the binding with free PFL.The enzymatic properties of the immobilized PFL were then evaluated,and then analysed the hydrolysate composition of anchovy oil catalyzed by the immobilized PFL.[Result ] The modified carriers exhibited lamellar structures with abundant free amino groups on the surface,which facilitated covalent immobilization …

Construction And Antibacterial Activity Evaluation Of A Lipopeptide Delivery System, Rong Chen, Mingye Guo, Ge Hou, Yan Chen

Journal of Food Science and Biotechnology

[Objective ] This study constructed a stable lipopeptide (LP) delivery system to improve the stability and dispersibility of LP,thereby enhancing their antibacterial efficacy.[Method ] LP particles were constructed with chitosan (CS) and sodium alginate (SA).Assembly property changes were evaluated by means of different construction and single factor experiments.Interactions among CS,LP,and SA were investigated by Fourier transform-infrared spectroscopy (FT-IR ),and the rheological properties of the system were examined by a rheometer.Antibacterial activity of LP particles was evaluated with Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus ) as model microorganisms.[Result ] LP particles prepared by dripping CS with the relative molecular mass …

Effects Of Modification Methods On The Processing Properties Of Cyperus Esculentus Powder, Xiaowei Sun, Chunli Song, Jian Ren

Journal of Food Science and Biotechnology

[Objective ] This study aims to explore the effects of three modification methods on the processing properties of Cyperus esculentus powder.[Method ] Three modification methods (superfine grinding,microwave treatment,and enzymatic treatment ) were employed to process Cyperus esculentus powder.The effects of these treatments on the processing properties including oil holding capacity,hydration properties,textural properties,and rheological properties of Cyperus esculentus powder were analyzed.[Result ] In comparison to the native Cyperus esculentus powder,ultrafine grinding treatment increased the specific surface area of the powder,enhanced the oil holding capacity by 74.57%,and significantly increased the loss angle (tan δ).Additionally,this treatment significantly increased the hardness,cohesiveness,and chewiness of the …

Composite Flours For Sustainable Food Systems: Integrating Nutritional, Environmental, And Climate Resilience Strategies, Rashmi H. Poojara, Soumya P S, Alvina Rose, Niva Somarajan

Journal of Environmental Science and Sustainable Development

Composite flour blends prepared from cereals, millets, tubers, legumes, and vegetables have gained increasing attention due to their potential to enhance nutritional quality, improve functional properties, and support sustainable food systems. Previous studies have largely focused on individual nutritional or functional attributes, with limited integration of environmental and health perspectives. This review aimed to systematically analyze how composite flours simultaneously influence nutritional quality, functional performance, health relevance, and environmental sustainability within a unified analytical framework. A systematic literature review was conducted following PRISMA guidelines. Peer-reviewed studies published between 2014 and 2025 were retrieved from PubMed, Scopus, Web of Science, and …

Effects Of Compound Protease Fermentation On The Industrial-Scale Production Of Very High Gravity Brewing Beer, Zongming Chang, Guangfeng Liu, Li Fang, Jiajie Zhang, Hua Yin

Journal of Food Science and Biotechnology

[Objective ] This study aims to address the technical problems of insufficient nitrogen content and an imbalanced amino acid composition in very high gravity wort produced with high-level syrup adjuncts.[Method ] This study investigated the effect of protease-assisted saccharification on wort protein composition.Then,a comprehensive evaluation was conducted on the brewing performance during 22 ° P very high gravity beer production.[Result ] During the proteolysis stage of saccharification,a synergistic addition of neutral protease and flavourzyme protease at a mass ratio of 6∶4 enabled efficient directed hydrolysis of malt proteins.In the wort,the α-amino nitrogen mass concentration was increased by 30%,while the mass …

Rapid Detection Of Aflatoxin B 1 Contamination Levels In Peanuts Based On Dual-Band Hyperspectral Imaging And Machine Learning, Lu Ren, Shuyue Shen, Wanrong Shi, Chuang Rui, Maofeng Dong, Tingting Li

Journal of Food Science and Biotechnology

[Objective ] This study aims to achieve rapid detection of AFB 1 contamination levels in peanuts through dual-band hyperspectral imaging and machine learning.[Method ] A peanut AFB 1 contamination level warning model was constructed via a dual-band hyperspectral imaging system consisting of visible near-infrared spectroscopy at 400~1 000 nm and short-wave near-infrared spectroscopy at 900~1 700 nm,combined with machine learning.Peanut samples with four contamination levels were collected,in which the mass fraction of AFB 1 was determined by ultra-high performance liquid chromatography-tandem mass spectrometry.The effects of four pretreatment methods [first derivative,second derivative,multiplicative scatter correction,and standard normal variate (SNV )],two characteristic wavelength …

Effects Of Aerated Storage On The Microbial Community And Functional Genes Of Pickles, Hengye Jing, Wei Deng, Fuliang Qi, Kun Tan, Rong She, Xiaoyan Yang

Journal of Food Science and Biotechnology

[Objective ] This study aims to investigate the effects of aeration on the microbial community structure and metabolic functional genes in pickles.[Method ] Amplicon sequencing was carried out for the 16S rRNA and ITS rRNA gene fragments from three groups (aerated group,sealed group,and the initial group ) within the same pickle system.The EasyAmplicon pipeline and PICRUSt 2 were employed to assess bacterial and fungal community diversity,composition,and functional gene variations.[Result ] Compared with the initial group,the sealed group showed only minor changes in microbial diversity,whereas the aerated group exhibited significant microbial divergence from the initial group.After aeration,the number of rare taxa …

Protective Effects Of Ovalbumin-Sodium Carboxymethylcellulose Colloidal Particles On Fish Oil Emulsions, Weichun Pan, Ya Wen, Huabin Liao, Feina Gu, Qiuping Zhang, Fuge Niu

Journal of Food Science and Biotechnology

[Objective ] This study aimed to investigate the impact of curcumin-loaded ovalbumin (OVA )-carboxymethylcellulose (CMC ) (OVA -CMC-Cur ) colloidal particles on the stability of fish oil emulsions.[Method ] The OVA -CMC-Cur colloidal particles were prepared with OVA and CMC at varying mass ratios and pH.The colloidal particles were then used as the stabilizer to prepare fish oil emulsions.The structural characteristics,stability,and digestive behaviors of the emulsions were investigated.[Result ] At the OVA -CMC mass ratio of 2∶1,the OVA -CMC-Cur particle-stabilized fish oil emulsions exhibited smaller particle sizes.These particles formed a dense,compact interfacial film at the oil-water interface,resulting in more uniform …

Research Progress In The Regulation Of Intestinal Stem Cell Homeostasis By Dietary Patterns, Haichao Zhang, Qi Sun, Yumei Qin, Yanpei Gu, Jianzhong Han

Journal of Food Science and Biotechnology

Intestinal stem cells (ISCs ) located at the bottom of intestinal crypts are the key factors driving the repair and rapid renewal of the intestinal epithelium.Their proliferation and differentiation are finely regulated by the microenvironment of the niche.ISCs,as dietary nutrient sensors,can respond to different dietary signals to regulate intestinal homeostasis.The author systematically summarizes the main signaling pathways involved in the regulation of ISCs and reviews the effects and functioning mechanisms of dietary patterns such as high-fat diets,intermittent fasting,calorie restriction,and ketogenic diets on the homeostasis of ISCs,aiming to provide a theoretical basis for the development and application of dietary intervention strategies …

Therapeutic Mechanisms Of A Lilium Brownii -Plantago Asiatica L.Compound Solid Beverage Against Hyperuricemia, Feng Li, Jiawei Huang, Xiaowen Guo, Lulu Jiang, Hongyan Zhao, Qiang Li, Chenxiang Sun, Shuying Feng, Qianqian Wang

Journal of Food Science and Biotechnology

[Objective ] This study aims to investigate the ameliorative effects of a Lilium brownii -Plantago asiatica L.compound solid beverage on hyperuricemia and to elucidate its potential mechanisms.[Method ] Network pharmacology was employed to screen the active constituents,potential targets,and related pathways.Key targets were identified based on a protein-protein interaction (PPI) network.Molecular docking was conducted between the key proteins and active constituents.An animal experiment was performed to validate the effects of the compound solid beverage on serum uric acid levels,renal function indices,activities of uric acid-producing enzymes,and the levels of renal urate transporters.[Result ] Network pharmacology analysis indicated that Lilium brownii and Plantago …

Research Progress In Enrichment Of Trace Elements Zinc And Selenium In Pleurotus Spp., Jing Zhang, Mengmeng Xu, Liting Zhao, Cui Li, Lei Chen, Song Ming, Zhongyang Ding

Journal of Food Science and Biotechnology

Zinc and selenium are essential trace elements for maintaining human normal physiological function.Deficiency of zinc or selenium can result in immune dysfunction,chronic diseases such as cardiovascular diseases and hyperlipidemia,and even increase the risk of cancer.The human body cannot independently synthesize these trace elements,which can only be obtained from the daily diet.However,natural food sources have low content of zinc and selenium,which is insufficient to meet the bod y’s needs.Therefore,developing fortified foods with trace nutrients is an important approach to meeting residents ’ requirements.Edible fungi serve as natural carriers for enriching trace elements and ideal dietary supplements.Pleurotus spp.,as a typical example,not only …

Construction And Optimization Of An Efficient Tyrosol Biosynthesis System In Escherichia Coli, Yizhe Xiong, Shougang Wang, Zhiming Rao, Meijuan Xu

Journal of Food Science and Biotechnology

[Objective ] An efficient biosynthetic system was constructed in Escherichia coli to achieve high-yield production of tyramine and its key derivative tyrosol.[Method ] Through the analysis of protein expression,enzymatic properties,and whole-cell catalysis results,tyrosine decarboxylase (TDC ) derived from Enterococcus faecalis was selected as the key enzyme for tyramine synthesis.Subsequently,tyramine oxidase (TYO ) was introduced to construct the TDC-TYO pathway for tyrosol production.Meanwhile,the LAAD-PDC pathway for tyrosol synthesis was established.A dual-enzyme co-expression system was established,and the effects of tandem enzyme order,production pathways,and key enzyme sources on tyrosol yield were analyzed.The recombinant strain B 1,carrying the plasmid pET 28a-EfTDC-TYO,was obtained through whole-cell …

Promoting The Synthesis Of Salicylic Acid In Escherichia Coli Based On Metabolic Engineering And Multi-Enzyme Cascade Strategy, Kai Wang, Xuewei Pan, Taowei Yang, Zhiming Rao

Journal of Food Science and Biotechnology

[Objective ] The production of the aromatic compound salicylic acid (SA) is limited by its inhibitory effects on enzymes related to cellular energy metabolism.This study aims to develop a strategy for avoiding the impact of SA on enzymes related to cellular energy metabolism and increase the yield of SA.[Method ] A highly efficient Escherichia coli strain was designed to improve SA production by optimizing metabolic pathways and enzyme systems.[Result ] The genome-scale metabolic model GEMS 1515 was employed to predict the key bottle necks in the phosphoenolpyruvic acid (PEP) pathway and SA biosynthesis pathways.The SA yield was successfully increased from …

Fermentation Technology Of L-Lysine Production By Immobilized Corynebacterium Glutamicum, Qingguo Liu, Hanjie Ying, Wenjun Sun

Journal of Food Science and Biotechnology

[Objective ] This study aimed to investigate the feasibility of the fermentation process for L-lysine production by immobilized Corynebacterium glutamicum.[Method ] Firstly,the effects of different volume fractions of seed medium on the fermentation stability of immobilized Corynebacterium glutamicum were examined.Subsequently,the impacts of immobilization carriers with different specifications on the fermentation performance were analyzed.Finally,a comparative analysis was conducted on the differences between the fermentation processes with free and immobilized Corynebacterium glutamicum.[Result ] The addition of 5% volume fraction of seed medium adequately sustained the growth and metabolic activities of Corynebacterium glutamicum.Higher volume fractions diverted carbon sources towards bacterial growth,thereby limiting product …