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Phovisay S, Abdullahi AD, Kham NNN, Unban K, Shetty K, Khanongnuch C. Microbial Population and Physicochemical Properties of Miang Fermented in Bamboo Tubes by the Luar Ethnic Group in Lao PDR. Foods 2024; 13:2109. [PMID: 38998615 PMCID: PMC11241543 DOI: 10.3390/foods13132109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Revised: 06/23/2024] [Accepted: 06/25/2024] [Indexed: 07/14/2024] Open
Abstract
Miang is a traditional fermented food made from Assam tea leaves and consumed as a snack. This study investigated the underground Miang fermentation process practiced by the Luar ethnic group in Laos, specifically examining the nutritional composition and microbial dynamics. Lactic acid bacteria and yeast were dominant in the fermentation process, reaching 8.43 and 8.50 log CFU/g after one week before gradually declining, while the coliform bacterial count was at 5.31 log CFU/g in the initial week but became undetectable in the later stages of fermentation. Next-generation sequencing identified Firmicutes (75.02%) and Proteobacteria (23.51%) as the primary phyla. Bacterial genera included Lactobacillus (73.36%) and Acetobacter (21.06%), with fungi mainly represented by Pichia (85.52%) and Candida (13.45%). Fundamental microbes such as Lactobacillus and Acetobacter were predominantly present, alongside Pichia and Candida, in the fungal communities. Microbial activities played a crucial role in generating essential enzymes for Miang's transformation. The nutritional transformation appears to be complete at 5 weeks of fermentation. The moisture content in the final products was approximately 74% and correlated with a change in nitrogen-free extract (NFE) and crude fiber. The fat content showed a slight increase from 1.3% to 2.52%, but protein content slightly declined from 17.21% to 16.05%, whereas ash content did not change significantly. Key polysaccharide-degrading enzymes, particularly pectinase and β-mannanase, were revealed and peaked at 48.32 and 25.32 U/g Miang, respectively. The total polyphenols increased from 103.54 mg/g dry Miang to 144.19-155.52 mg/g during fermentation. The lowered IC50 value indicated an increase in antioxidant activity. A fermentation period of at least 3 weeks proved to be optimal for enhancing antioxidant properties and bioactive compounds, and mitigating the risk of coliform bacteria.
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Affiliation(s)
- Somsay Phovisay
- Multidisciplinary School, Chiang Mai University, Chiang Mai 50200, Thailand; (S.P.); (A.D.A.); (N.N.N.K.)
| | - Aliyu Dantani Abdullahi
- Multidisciplinary School, Chiang Mai University, Chiang Mai 50200, Thailand; (S.P.); (A.D.A.); (N.N.N.K.)
| | - Nang Nwet Noon Kham
- Multidisciplinary School, Chiang Mai University, Chiang Mai 50200, Thailand; (S.P.); (A.D.A.); (N.N.N.K.)
| | - Kridsada Unban
- Division of Food Science and Technology, Faculty of Agro-Industry, Chiang Mai University, Chiang Mai 50100, Thailand
- Research Center for Multidisciplinary Approaches to Miang, Multidisciplinary Research Institute (MDRI), Chiang Mai University, Chiang Mai 50200, Thailand
| | - Kalidas Shetty
- Global Institute of Food Security and International Agriculture (GIFSIA), Department of Plant Sciences, North Dakota State University, Fargo, ND 58108, USA;
| | - Chartchai Khanongnuch
- Research Center for Multidisciplinary Approaches to Miang, Multidisciplinary Research Institute (MDRI), Chiang Mai University, Chiang Mai 50200, Thailand
- Department of Biology, Faculty of Science, Chiang Mai University, Huay Kaew Rd., Chiang Mai 50200, Thailand
- Research Center of Microbial Diversity and Sustainable Utilization, Chiang Mai University, Huay Kaew Rd., Chiang Mai 50200, Thailand
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Zheng Y, Li Y, Pan L, Guan M, Yuan X, Li S, Ren D, Gu Y, Liang M, Yi L. Aroma and taste analysis of pickled tea from spontaneous and yeast-enhanced fermentation by mass spectrometry and sensory evaluation. Food Chem 2024; 442:138472. [PMID: 38278105 DOI: 10.1016/j.foodchem.2024.138472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 01/08/2024] [Accepted: 01/15/2024] [Indexed: 01/28/2024]
Abstract
Anaerobically fermented pickled tea (PT) can be produced by spontaneous fermentation (SF) or yeast-enhanced fermentation (YF). Aroma and taste characteristics of PT during YF and SF were investigated using sensory evaluation, odour activity, aroma character impact values, HS-SPME-GC-MS, UPLC-QQQ-MS/MS, and spectrophotometry, annotating 198 volatile and 115 non-volatile components. The main contributing volatile components were β-ionone, and 1-octanol, promoted by YF and SF, and yielding floral and fruity aromas respectively. Additionally, compared with SF, YF promoted the formation of citronellol yielding a floral aroma, inhibited the stale aroma of methoxybenzenes, and reduced bitter, astringent, and sour tastes. Furthermore, partial least-squares regression analysis identified the main components related to the 'acides aroma' of PT as linalool oxide, n-decanoic acid, hexanoic acid, 3,7-dimethyl-2,6-octadienoic acid, 3-methyl-1-dodecyn-3-ol, and nerolidol. This application could be used as methodology for the comprehensive analysis of tea aroma and taste and these results can act as guidelines for PT production and quality control.
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Affiliation(s)
- Yaru Zheng
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China
| | - Yingcai Li
- Kunming Institute for Food and Drug Control, Kunming 650032, PR China
| | - Lianyun Pan
- Yunnan Key Laboratory of Tea Science, Tea Research Institute of Yunnan Academy of Agricultural Sciences, Kunming 650221, PR China
| | - Mengdi Guan
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China
| | - Xiaoping Yuan
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China
| | - Siyu Li
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China
| | - Dabing Ren
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China.
| | - Ying Gu
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China.
| | - Mingzhi Liang
- Yunnan Key Laboratory of Tea Science, Tea Research Institute of Yunnan Academy of Agricultural Sciences, Kunming 650221, PR China.
| | - Lunzhao Yi
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China.
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Kharazian ZA, Xu D, Su R, Guo X. Effects of inoculation and dry matter content on microbiome dynamics and metabolome profiling of sorghum silage. Appl Microbiol Biotechnol 2024; 108:257. [PMID: 38456919 PMCID: PMC10923742 DOI: 10.1007/s00253-024-13096-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/22/2024] [Accepted: 02/28/2024] [Indexed: 03/09/2024]
Abstract
Sorghum forage was ensiled for 90 days at two dry matter (DM) contents (27 vs. 39%) without or with Lactiplantibacillus plantarum inoculation. On day 90 of fermentation, silages were sampled to assess the microbial community dynamics and metabolome profile. L. plantarum inoculation improved silage quality, as shown by a lower pH and greater acetic acid concentration. Loss of DM remained unaffected by L. plantarum inoculation but was greater in low- vs. high-DM sorghum silages (14.4 vs. 6.62%). The microbiome analysis revealed that Pseudomonas congelans represented the dominant species of the epiphytic microbiota in both low- and high-DM sorghum forage before ensiling. However, L. buchneri represented the dominant species at the end of ensiling. Ensiling fermentation resulted in distinct metabolic changes in silages with varying DM content. In low-DM silages, ensiling fermentation led to the accumulation of 24 metabolites and a reduction in the relative concentration of 13 metabolites. In high-DM silages, ensiling fermentation resulted in an increase in the relative concentration of 26 metabolites but a decrease in the concentration of 8 metabolites. Compared to non-inoculated silages, L. plantarum inoculation resulted in an increased concentration of 3 metabolites and a reduced concentration of 5 metabolites in low-DM silages. Similarly, in high-DM silages, there was an elevation in the relative concentration of 3 metabolites, while a decrease in 7 other metabolites. Ten metabolites with bio-functional activity were identified, including chrysoeriol, isorhamnetin, petunidin 3-glucoside, apigenin, caffeic acid, gallic acid, p-coumaric acid, trans-cinnamic acid, herniarin, and 3,4-dihydroxy-trans-cinnamate. This study presents a comprehensive analysis of microbiome and metabolome profiling of sorghum forage during ensiling as a function of DM content and L. plantarum inoculation, with a particular emphasis on identifying metabolites that may possess bio-functional properties. KEY POINTS: • DM loss was not different by L. plantarum but higher in low- vs. high-DM silage. • L. buchneri dominated ensiling, regardless of DM level. • 10 metabolites with bio-functional activity were identified.
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Affiliation(s)
- Zohreh Akhavan Kharazian
- State Key Laboratory of Grassland and Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
- Probiotics and Biological Feed Research Center, Lanzhou University, Lanzhou, 730000, China
| | - Dongmei Xu
- State Key Laboratory of Grassland and Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
- Probiotics and Biological Feed Research Center, Lanzhou University, Lanzhou, 730000, China
| | - Rina Su
- State Key Laboratory of Grassland and Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
- Probiotics and Biological Feed Research Center, Lanzhou University, Lanzhou, 730000, China
| | - Xusheng Guo
- State Key Laboratory of Grassland and Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.
- Probiotics and Biological Feed Research Center, Lanzhou University, Lanzhou, 730000, China.
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Li M, Bai W, Yang Y, Zhang X, Wu H, Li Y, Xu Y. Waste Tea-Derived Theabrownins for Solar-Driven Steam Generation. ACS APPLIED MATERIALS & INTERFACES 2024; 16:10158-10169. [PMID: 38354064 DOI: 10.1021/acsami.3c18438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
Solar-driven seawater desalination has been considered an effective and sustainable solution to mitigate the global freshwater crisis. However, the substantial cost associated with photothermal materials for evaporator fabrication still hinders large-scale manufacturing for practical applications. Herein, we successfully obtained high yields of theabrownins (TB), which were oxidation polymerization products of polyphenols from waste and inferior tea leaves using a liquid-state fermentation strategy. Subsequently, a series of photothermal complexes were prepared based on the metal-phenolic networks assembled from TB and metal ions (Fe(III), Cu(II), Ni(II), and Zn(II)). Also, the screened TB@Fe(III) complexes were directly coated on a hydrophilic poly(vinylidene fluoride) (PVDF) membrane to construct the solar evaporation device (TB@Fe(III)@PVDF), which not only demonstrated superior light absorption property and notable hydrophilicity but also achieved a high water evaporation rate of 1.59 kg m-2 h-1 and a steam generation efficiency of 90% under 1 sun irradiation. More importantly, its long-term stability and exceptionally low production cost enabled an important step toward the possibility of large-scale practical applications. We believe that this study holds the potential to pave the way for the development of sustainable and cost-effective photothermal materials, offering new avenues for utilization of agriculture resource waste and solar-driven water remediation.
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Affiliation(s)
- Maoyun Li
- Huaxi MR Research Center, Department of Radiology, Functional and Molecular Imaging Key Laboratory of Sichuan Province, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Wanjie Bai
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610041, China
| | - Yiyan Yang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610041, China
| | - Xueqian Zhang
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610041, China
| | - Haoxing Wu
- Huaxi MR Research Center, Department of Radiology, Functional and Molecular Imaging Key Laboratory of Sichuan Province, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Yiwen Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610041, China
| | - Yuanting Xu
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610041, China
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5
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Sun Y, Yuan X, Luo Z, Cao Y, Liu S, Liu Y. Metabolomic and transcriptomic analyses reveal comparisons against liquid-state fermentation of primary dark tea, green tea and white tea by Aspergillus cristatus. Food Res Int 2023; 172:113115. [PMID: 37689883 DOI: 10.1016/j.foodres.2023.113115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 06/05/2023] [Accepted: 06/09/2023] [Indexed: 09/11/2023]
Abstract
Liquid-state fermentation (LSF) of tea leaves is a promising way to obtain tea-based nutraceutical products rich in various bioactive compounds. In the study, the changes of bioactive compounds, tea pigments and complex metabolites from LSF of primary dark tea, green tea and white tea infusions with Aspergillus cristatus were determined. Chemical analyses revealed that soluble sugars, monosaccharide composition, total polyphenols, total flavonoids, free amino acids, soluble proteins and tea pigments were changed in different ways. An untargeted metabolomic analysis and ribonucleic acid sequencing (RNA-seq) based transcriptomic analysis were performed to investigate the metabolic differentiation and clarify the key differentially expressed genes (DEGs, fold change >2 and p < 0.05), showing that amino acid metabolism, carbohydrate metabolism and lipid metabolism were the most enriched pathways during A. cristatus fermentation of primary dark tea, green tea and white tea infusions. In addition, glycerophospholipid metabolism, linoleic acid metabolism and phenylalanine metabolism were greatly accumulated in the fermentation of primary dark tea and white tea infusions; Pyruvate metabolism, glycolysis/gluconeogenesis, fatty acid degradation, tyrosine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis and valine and leucine, isoleucine degradation were greatly accumulated in the fermentation of primary dark tea and green tea infusions; Starch and sucrose metabolism was greatly accumulated in the fermentation of green tea and white tea infusions; Galactose metabolism was significantly enhanced in the fermentation of primary dark tea infusion; Amino sugar and nucleotide sugar metabolism, sphingolipid metabolism and alanine, aspartate and glutamate metabolism were significantly enhanced in the fermentation of green tea infusion. Besides, some other pathways involving aminobenzoate degradation, biosynthesis of cofactors, pyrimidine metabolism, benzoxazinoid biosynthesis and phenazine biosynthesis, tropane, piperidine and pyridine alkaloid biosynthesis and flavone and flavonol biosynthesis also differed from each other. These findings support that A. cristatus plays a vital role in the biochemical and genetic regulation of metabolite profile, and could be considered a potential prospect for better use of A. cristatus on different kinds of tea materials.
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Affiliation(s)
- Yujiao Sun
- Natural Food Macromolecule Research Center, School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, PR China; Shaanxi Research Institute of Agricultural Products Processing Technology, Xi'an 710021, PR China.
| | - Xushuang Yuan
- Natural Food Macromolecule Research Center, School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, PR China
| | - Zhaojun Luo
- Natural Food Macromolecule Research Center, School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, PR China
| | - Yungang Cao
- Natural Food Macromolecule Research Center, School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, PR China
| | - Shuai Liu
- Shaanxi Academy of Traditional Chinese Medicine, Xi'an 710003, PR China
| | - Yang Liu
- Shaanxi Academy of Traditional Chinese Medicine, Xi'an 710003, PR China.
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6
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Ma W, Zhu Y, Ma S, Shi J, Yan H, Lin Z, Lv H. Aroma characterisation of Liu-pao tea based on volatile fingerprint and aroma wheel using SBSE-GC-MS. Food Chem 2023; 414:135739. [PMID: 36827782 DOI: 10.1016/j.foodchem.2023.135739] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/07/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023]
Abstract
Liu-pao tea (LPT) has unique aroma characteristics, and is a special microbial fermented tea produced using dark raw tea (LPM) as its raw material. In this study, stir bar sorptive extraction (SBSE) combined with gas chromatography-mass spectrometry (GC-MS) was applied to investigate the volatiles of 16 LPTs and 6 LPMs. Moreover, variations in volatile profiles between LPTs and LPMs were explored. Results showed that a total of 132 volatile compounds were identified from LPTs. The volatile fingerprint was constructed with a similarity ranged from 0.85 to 0.99. Furthermore, twenty-six aroma compounds were selected to depict the molecular aroma wheel of LPT. Multivariate statistical analysis revealed that the contents of 24 aroma compounds changed significantly (P < 0.05) when LPMs were processed into LPTs. These results reveal the volatile profiles of LPTs and aroma composition changes during microbial fermentation process, which might provide chemical basis of the aroma quality of LPT.
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Affiliation(s)
- Wanjun Ma
- Key Laboratory of Tea Biology and Resource Utilization of Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; Graduate School of Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yin Zhu
- Key Laboratory of Tea Biology and Resource Utilization of Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China.
| | - Shicheng Ma
- Wuzhou Liu-pao Tea Research Association, Wuzhou 543000, China
| | - Jiang Shi
- Key Laboratory of Tea Biology and Resource Utilization of Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
| | - Han Yan
- Key Laboratory of Tea Biology and Resource Utilization of Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; Graduate School of Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Zhi Lin
- Key Laboratory of Tea Biology and Resource Utilization of Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
| | - Haipeng Lv
- Key Laboratory of Tea Biology and Resource Utilization of Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China.
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Yang S, Fan L, Tan P, Lei W, Liang J, Gao Z. Effects of Eurotium cristatum on chemical constituents and α-glucosidase activity of mulberry leaf tea. FOOD BIOSCI 2023. [DOI: 10.1016/j.fbio.2023.102557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
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8
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Hou Y, Mao H, Lu F, Ma C, Zhu S, Li G, Huang S, Zhang Y, Lv C, Xiao R. Widely targeted metabolomics and HPLC analysis elaborated the quality formation of Yunnan pickled tea during the whole process at an industrial scale. Food Chem 2023; 422:135716. [PMID: 37156017 DOI: 10.1016/j.foodchem.2023.135716] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 01/30/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023]
Abstract
Yunnan pickled tea is produced from fresh tea-leaves through fixation, rolling, anaerobic fermentation and sun-drying. In this study, widely targeted metabolomics using UHPLC-QQQ-MS/MS and HPLC analysis were carried out to elaborate its quality formation during the whole process. Results confirmed the contribution of preliminary treatments and anaerobic fermentation to the quality formation. A total of 568 differential metabolites (VIP > 1.0, P < 0.05, FC > 1.50 or < 0.67) were screened through OPLS-DA. (-)-Epigallocatechin and (-)-epicatechin significantly (P < 0.05) increased from the hydrolyzation of ester catechins, such as (-)-epigallocatechin gallate and (-)-epicatechin gallate in anaerobic fermentation. Additionally, the anaerobic fermentation promoted vast accumulations of seven essential amino acids, four phenolic acids, three flavones and flavone glycosides, pelargonidin and pelargonidin glycosides, flavonoids and flavonoid glycosides (i.e. kaempferol, quercetin, taxifolin, apigenin, myricetin, luteolin and their glycosides) through relevant N-methylation, O-methylation, hydrolyzation, glycosylation and oxidation.
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Affiliation(s)
- Yan Hou
- College of Tea, Yunnan Agriculture University, Kunming 650201, Yunnan, China; College of Food Science and Technology, Yunnan Agriculture University, Kunming 650201, Yunnan, China.
| | - Honglin Mao
- College of Food Science and Technology, Yunnan Agriculture University, Kunming 650201, Yunnan, China
| | - Fengmei Lu
- Yunnan Defeng Tea Co., Ltd, Mangshi 678400, Yunnan, China
| | - Cunqiang Ma
- College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China
| | - Shaoxian Zhu
- College of Food Science and Technology, Yunnan Agriculture University, Kunming 650201, Yunnan, China
| | - Guoyou Li
- College of Food Science and Technology, Yunnan Agriculture University, Kunming 650201, Yunnan, China
| | - Siqi Huang
- College of Food Science and Technology, Yunnan Agriculture University, Kunming 650201, Yunnan, China
| | - Yi Zhang
- Yunnan Defeng Tea Co., Ltd, Mangshi 678400, Yunnan, China
| | - Caiyou Lv
- College of Tea, Yunnan Agriculture University, Kunming 650201, Yunnan, China.
| | - Rong Xiao
- College of Food Science and Technology, Yunnan Agriculture University, Kunming 650201, Yunnan, China.
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Du J, Wu X, Sun S, Qin Y, Liao K, Liu X, Qiu R, Long Z, Zhang L. Study on inoculation fermentation by fungi to improve the taste quality of summer green tea. FOOD BIOSCI 2023. [DOI: 10.1016/j.fbio.2022.102321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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10
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Wen M, Zhou F, Zhu M, Han Z, Lai G, Jiang Z, Long P, Zhang L. Monitoring of pickled tea during processing: From LC-MS based metabolomics analysis to inhibitory activities on α-amylase and α-glycosidase. J Food Compost Anal 2022. [DOI: 10.1016/j.jfca.2022.105108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Evaluation of the effects of solar withering on nonvolatile compounds in white tea through metabolomics and transcriptomics. Food Res Int 2022; 162:112088. [DOI: 10.1016/j.foodres.2022.112088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/20/2022] [Accepted: 10/26/2022] [Indexed: 11/22/2022]
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12
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Changes in Bioactive Compounds, Antioxidant Activities and Chemical Properties of Pickled Tea By-Product Fermentation: Promising Waste Management and Value-Added Product. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8100472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Pickled tea is an ethnic fermented product produced using Assam tea (Camellia sinensis var. assamica) leaves. It is produced in large quantities every year and the liquid waste from its production is estimated to be up to 2500 mL per every kilogram of pickled tea production. To reduce the waste, pickled tea juice remaining from the process was developed into (1) pineapple kombucha and (2) formulated functional drinks as “value added” products. The juice used for making kombucha was collected at 15 days of pickled tea fermentation due to its high value in antioxidant activity (previous study, 2250 µmol TE per g DW). After fermenting the juice with starter culture, the properties of pineapple kombucha were assessed at 0, 1, 3, 5, 7, 9, 11 days. Results showed that the total phenolic of pineapple kombucha was reduced, while antioxidant assay (FRAP and ORAC) slightly increased. The most suitable fermentation period of pineapple kombucha was at day 3. The formulated drink was made from mixing pineapple kombucha with ginger and lemon juice at various ratios including 100:0:0, 80:10:10 and 80:15:5. The ratio 80:10:10 gave the highest TP and antioxidant activity for the functional drink. In addition, for sensory analysis, liking attribute of 80:15:5 fermented juice kombucha pineapple favor was significantly higher compared to other formulations. The study demonstrates the promising second fermentation process of by-product juice from pickled tea production for the conversion to value-added functional drink with reasonable antioxidant properties.
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Tawfik A, Mostafa A, Elsamadony M, Pant D, Fujii M. Unraveling the metabolic shift in anaerobic digestion pathways associated with the alteration of onion skin waste concentration. ENVIRONMENTAL RESEARCH 2022; 212:113494. [PMID: 35660404 DOI: 10.1016/j.envres.2022.113494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 05/08/2022] [Accepted: 05/14/2022] [Indexed: 06/15/2023]
Abstract
Onion skin waste (OSW) is common waste in developing countries, which can cause severe environmental pollution when not properly treated. Value-added products can be chemically extracted from OSW; however, that process is not economically feasible. Alternatively, dry anaerobic digestion (DAD) of OSW is a promising approach for both energy recovery and environment protection. The main hurdles during DAD of OSW can be the hydrolysis and acidification. In batch tests, sludge digestate (SD) rich with methanogens was co-digested with different fractions of OSW for enhancing hydrolysis and raising biogas productivity. The cumulative biogas production (CBP) was 36.6 ± 0.3 mL for sole DAD of SD (100% SD) and increased up to 281.9 ± 14.1 mL for (50% SD: 50% OSW) batch. Self-delignification of OSW took place by SD addition, where the lignin removal reached 75.3 ± 10.5% for (85% SD: 15% OSW) batch. Increasing the fraction of OSW (45% SD: 55% OSW) reduced the delignification by a value of 68.8%, where initial lignin concentration was 9.48 ± 1.6% in dry weight. Lignin breaking down resulted a high fraction of phenolic compounds (345.6 ± 58.8 mg gallic acid equivalent/g dry weight) in the fermentation medium, causing CBP drop (219.0 ± 28.5 mL). The presence of elements (K, Ca, Mg, Fe, Zn, Mn, S and P) in OSW improved the enzymatic activity, facilitated phenolic compounds degradation, shifted the metabolism towards acetate fermentation pathway, and raised biogas productivity. Acidogenesis was less affected by phenolic compounds than methanogenesis, causing higher H2 contents and lower CH4 contents, at batches with high share of OSW.
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Affiliation(s)
- Ahmed Tawfik
- National Research Centre, Water Pollution Research Department, 12622, Dokki, Cairo, Egypt
| | - Alsayed Mostafa
- Department of Smart-city Engineering, Inha University, 100 Inharo, Nam-gu, Incheon, 22212, South Korea
| | - Mohamed Elsamadony
- Department of Public Works Engineering, Faculty of Engineering, Tanta University, 31521 Tanta City, Egypt; Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-Ku, Tokyo, 152-8552, Japan.
| | - Deepak Pant
- Separation & Conversion Technology, Flemish Institute for Technological Research (VITO), Boeretang 200, Mol, 2400, Belgium
| | - Manabu Fujii
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-Ku, Tokyo, 152-8552, Japan
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Tang VCY, Sun J, Pua A, Goh RMV, Huang Y, Ee KH, Lassabliere B. Biovalorisation of spent Konacha tea leaves via single-culture fermentation involving wine yeasts and lactic acid bacteria. J Appl Microbiol 2022; 133:1461-1478. [PMID: 35656986 DOI: 10.1111/jam.15650] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 05/19/2022] [Accepted: 05/30/2022] [Indexed: 10/18/2022]
Abstract
AIMS The objective of this study was to explore the potential of fermentation as a biovalorisation strategy for spent tea leaves (STL), a major agri-food waste generated from the tea extraction industry. Fermentation by wine yeasts or lactic acid bacteria (LAB) have shown promising results in previous studies across various substrates. METHODS AND RESULTS Konacha (green tea) STL slurries were inoculated with single strains of wine yeasts or LAB, respectively. After a 48-h fermentation, changes in selected non-volatile and volatile compositions were evaluated. Fermentation by LAB increased organic acid content by 5- to 7-fold (except Lactobacillus fermentum) and modulated the composition of major tea catechins, while wine yeast fermentation resulted in a 30% increase in amino acid content. Strain-specific production of specific volatile compounds was also observed, such as butanoic acid (L. fermentum), isoamyl acetate (Pichia kluyveri) and 4-ethylphenol (L. plantarum). CONCLUSIONS Both volatile and non-volatile compound compositions of Konacha STL were successfully modified via wine yeast and LAB fermentation. SIGNIFICANCE AND IMPACT OF STUDY Our findings indicate that Konacha STL is a suitable medium for biovalorisation by wine yeasts or LAB via the generation of commercially useful volatile and non-volatile compounds. Future optimizations could further render fermentation an economically viable strategy for the upcycling of STL.
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Affiliation(s)
| | - Jingcan Sun
- Mane SEA Pte Ltd, 3 Biopolis Drive, #07-17/18/19 Synapse, Singapore 138623
| | - Aileen Pua
- Mane SEA Pte Ltd, 3 Biopolis Drive, #07-17/18/19 Synapse, Singapore 138623.,Department of Food Science and Technology, National University of Singapore, S14 Level 5, Science Drive 2, Singapore 117542
| | - Rui Min Vivian Goh
- Mane SEA Pte Ltd, 3 Biopolis Drive, #07-17/18/19 Synapse, Singapore 138623
| | - Yunle Huang
- Mane SEA Pte Ltd, 3 Biopolis Drive, #07-17/18/19 Synapse, Singapore 138623.,Department of Food Science and Technology, National University of Singapore, S14 Level 5, Science Drive 2, Singapore 117542
| | - Kim Huey Ee
- Mane SEA Pte Ltd, 3 Biopolis Drive, #07-17/18/19 Synapse, Singapore 138623
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15
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Yu Z, Deng H, Qu H, Zhang B, Lei G, Chen J, Feng X, Wu D, Huang Y, Ji Z. Penicillium simplicissimum possessing high potential to develop decaffeinated Qingzhuan tea. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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16
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Xu H, Sun J, Zhao Z, Ma X, Li C, Liu L, Zhang G. Lactobacillus plantarum
ZLC‐18 fermentation improve tyrosinase inhibition activity and antioxidant capacity in soybean hulls. Int J Food Sci Technol 2022. [DOI: 10.1111/ijfs.15788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hanxue Xu
- Key Laboratory of Dairy Sciences Ministry of Education College of Food Sciences Northeast Agricultural University Harbin China
| | - Jinwei Sun
- Key Laboratory of Dairy Sciences Ministry of Education College of Food Sciences Northeast Agricultural University Harbin China
- Product Research and Development Center Newhopedairy Co., Ltd Chengdu China
| | - Zifu Zhao
- Key Laboratory of Dairy Sciences Ministry of Education College of Food Sciences Northeast Agricultural University Harbin China
- Inner Mongolia Yili Group Co Ltd, Hohhot China
| | - Xinkai Ma
- Key Laboratory of Dairy Sciences Ministry of Education College of Food Sciences Northeast Agricultural University Harbin China
| | - Chun Li
- Key Laboratory of Dairy Sciences Ministry of Education College of Food Sciences Northeast Agricultural University Harbin China
- Heilongjiang Green Food Research Institute Harbin China
| | - Libo Liu
- Key Laboratory of Dairy Sciences Ministry of Education College of Food Sciences Northeast Agricultural University Harbin China
| | - Guofang Zhang
- Key Laboratory of Dairy Sciences Ministry of Education College of Food Sciences Northeast Agricultural University Harbin China
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17
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Li M, Xiao Y, Zhong K, Wu Y, Gao H. Delving into the Biotransformation Characteristics and Mechanism of Steamed Green Tea Fermented by Aspergillus niger PW-2 Based on Metabolomic and Proteomic Approaches. Foods 2022; 11:foods11060865. [PMID: 35327286 PMCID: PMC8951510 DOI: 10.3390/foods11060865] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/15/2022] [Accepted: 03/15/2022] [Indexed: 02/04/2023] Open
Abstract
Aspergillus niger is one of the dominant microorganisms presented in dark tea fermentation. In this study, the biotransformation of steamed green tea leaves fermented by A. niger PW-2 was characterized using metabolomic and proteomic approaches. We observed that, after fermentation, the contents of volatile compounds contributing to the “green” aroma, including linalool, L-α-terpineol and geraniol, decreased significantly. Meanwhile, the astringency taste and contents of metabolites contributing to the taste (catechins) reduced significantly during fermentation. Additionally, the contents of theabrownins, which have health benefits, obviously increased. The bitter and umami tastes were also changed due to the variations in bitter-taste and umami-taste amino acids. We also found that glycoside hydrolases, tannases, catechol oxidases, peroxidases and laccases secreted by A. niger PW-2 were responsible for the metabolism of phenolic compounds and their derivatives (theaflavins, thearubingins and theabrownins). Finally, the metabolic pathways involved in the biosynthesis and degradation of characteristic metabolites were found to reveal the biotransformation characteristics of dark tea fermented with A. niger PW-2.
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Affiliation(s)
- Maoyun Li
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; (M.L.); (K.Z.); (H.G.)
| | - Yue Xiao
- West China School of Public Health, Sichuan University, Chengdu 610065, China;
| | - Kai Zhong
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; (M.L.); (K.Z.); (H.G.)
| | - Yanping Wu
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; (M.L.); (K.Z.); (H.G.)
- Correspondence:
| | - Hong Gao
- College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China; (M.L.); (K.Z.); (H.G.)
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18
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Sun L, Dong X, Ren Y, Agarwal M, Ren A, Ding Z. Profiling Real-Time Aroma from Green Tea Infusion during Brewing. Foods 2022; 11:foods11050684. [PMID: 35267316 PMCID: PMC8909371 DOI: 10.3390/foods11050684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/23/2022] [Accepted: 02/24/2022] [Indexed: 02/05/2023] Open
Abstract
Aroma substances are the most crucial criteria for the sensory evaluation of tea quality, and also key attractors influencing consumers to make the decision for purchasing tea. Understanding the aromatic properties of tea infusion during different brewing time is crucial to control the tea aromatic quality. Here, headspace and direct immersion solid-phase microextraction (HS-SPME and DI-SPME), coupled with GC-MS, were employed to investigate the impact of brewing time on the changes of the volatile features of green tea infusion. Esters, aldehydes, alcohols, fatty acids, and alkaloids were the predominant volatile groups from tea infusions. Two to three minutes was identified as the best duration for the tea brewing that can maximize the abundance of aromatic chemicals in the headspace emitted from the tea infusions. The variation of the key aromatic contributors between the tea infusion and the headspace over the infusion tended to equilibrate during the tea brewing process. This study provides a theory-based reference method by analyzing the real-time aromatic characteristics in green tea. The optimal time was determined for aromatic quality control, and the complementary relationship between the volatiles in the headspace and its counterpart, tea infusion, was primarily elucidated.
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Affiliation(s)
- Litao Sun
- Tea Research Institute, Qingdao Agricultural University, Qingdao 266109, China;
- College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Perth, WA 6150, Australia; (X.D.); (Y.R.); (M.A.); (A.R.)
| | - Xue Dong
- College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Perth, WA 6150, Australia; (X.D.); (Y.R.); (M.A.); (A.R.)
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, 50 Zhongling Street, Nanjing 210014, China
| | - Yonglin Ren
- College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Perth, WA 6150, Australia; (X.D.); (Y.R.); (M.A.); (A.R.)
| | - Manjree Agarwal
- College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Perth, WA 6150, Australia; (X.D.); (Y.R.); (M.A.); (A.R.)
| | - Alexander Ren
- College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Perth, WA 6150, Australia; (X.D.); (Y.R.); (M.A.); (A.R.)
| | - Zhaotang Ding
- Tea Research Institute, Qingdao Agricultural University, Qingdao 266109, China;
- College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Perth, WA 6150, Australia; (X.D.); (Y.R.); (M.A.); (A.R.)
- Correspondence:
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19
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Zhou B, Ma B, Ma C, Xu C, Wang J, Wang Z, Yin D, Xia T. Classification of Pu-erh ripened teas and their differences in chemical constituents and antioxidant capacity. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2021.112370] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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20
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Zhang H, Chen Y, Guo Y, Xu W, Wang W, Wu S, Chen W, Huang Y. Label-free quantification proteomics reveals the active peptides from protein degradation during anaerobic fermentation of tea. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.111950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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21
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Zhong H, Zhao M, Tang J, Deng L, Feng F. Probiotics-fermented blueberry juices as potential antidiabetic product: antioxidant, antimicrobial and antidiabetic potentials. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:4420-4427. [PMID: 33421121 DOI: 10.1002/jsfa.11083] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 12/17/2020] [Accepted: 01/09/2021] [Indexed: 05/10/2023]
Abstract
BACKGROUND Fermentation is a traditional food-preserving technique. It is an effective process, widely used to enrich the nutrients diversity and bioactivity of the fermented foods since ancient times. This study aimed at investigating the effects of various fermentation starters on the physicochemical, antioxidant, antimicrobial, and antidiabetic properties of blueberry juices. The blueberry juices were fermented by natural fermentation (NFBJ), self-made starters fermentation (SFBJ), and commercial starters fermentation (CFBJ); fresh blueberry juice (BBJ) was processed without fermentation for comparison. RESULTS Probiotics-fermented blueberry juices (SFBJ and CFBJ) showed less total and reducing sugars, higher titratable acidity, and a wider variety and higher amounts of organic acids than non-fermented blueberry juice (BBJ) did. All the fermented blueberry juices (NFBJ, SFBJ, and CFBJ) showed significantly (P < 0.05) higher antioxidant potentials than that of BBJ measured by 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid, cupric-reducing antioxidant capacity, and ferric-reducing ability power assays. The SFBJ exhibited the highest antibacterial activities against Escherichia coli, Staphylococcus aureus, and Salmonella Typhimurium, with inhibition zone diameters of 38.84 ± 1.74 mm, 34.91 ± 1.53 mm, and 36.18 ± 3.16 mm respectively. Compared with BBJ, the α-glucosidase inhibitory activity of the SFBJ and CFBJ increased by two-to threefold. The α-amylase inhibitory activity of the SFBJ and CFBJ increased by 600%, whereas the spontaneous fermentation showed no improvement. The SFBJ and CFBJ promoted glucose consumption of HepG2 cell lines, indicating the promising potential for a higher glucose bio-utilization. CONCLUSIONS The SFBJ and CFBJ showed remarkable improvements in the antioxidant, antimicrobial, and antidiabetic activities compared with non-fermented and spontaneous fermented juices, indicating their promising potentials as an antihyperglycemic agent. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Hao Zhong
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
- Ningbo Institute of Zhejiang University, Ningbo, China
| | - Minjie Zhao
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
- Ningbo Institute of Zhejiang University, Ningbo, China
| | - Jun Tang
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
- Ningbo Institute of Zhejiang University, Ningbo, China
| | - Lingli Deng
- College of Biological Science and Technology, Hubei Minzu University, Enshi, China
| | - Fengqin Feng
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
- Ningbo Institute of Zhejiang University, Ningbo, China
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22
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Kodchasee P, Nain K, Abdullahi AD, Unban K, Saenjum C, Shetty K, Khanongnuch C. Microbial dynamics-linked properties and functional metabolites during Miang fermentation using the filamentous fungi growth-based process. FOOD BIOSCI 2021. [DOI: 10.1016/j.fbio.2021.100998] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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The effect of Eurotium cristatum (MF800948) fermentation on the quality of autumn green tea. Food Chem 2021; 358:129848. [PMID: 33933981 DOI: 10.1016/j.foodchem.2021.129848] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 02/21/2021] [Accepted: 04/09/2021] [Indexed: 11/21/2022]
Abstract
Autumn green tea (AT) has poor taste quality for its strong astringency. This study aims to improve the taste quality as well as the aroma of AT by Eurotium cristatum (MF800948) fermentation and to produce a fermented autumn green tea (FT). Results showed that the aroma quality of AT was improved, and the content of terpene alcohols that impart characteristic flowery aroma to FT significantly increased. The umami intensity of FT was comparable to that of AT while the astringency tasted much weaker mainly due to the oxidation of the catechins. The results also confirmed that theabrownins exhibited strong umami taste, not astringent taste. Finally, a metabolic map was analyzed to show the effect of E. cristatum (MF800948) on the quality of AT, and to visualize the changes of differential compounds in AT and FT. The work provides insights into the quality improvement of autumn green tea.
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24
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Ma C, Li X, Zheng C, Zhou B, Xu C, Xia T. Comparison of characteristic components in tea-leaves fermented by Aspergillus pallidofulvus PT-3, Aspergillus sesamicola PT-4 and Penicillium manginii PT-5 using LC-MS metabolomics and HPLC analysis. Food Chem 2021; 350:129228. [PMID: 33618088 DOI: 10.1016/j.foodchem.2021.129228] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 01/02/2021] [Accepted: 01/25/2021] [Indexed: 12/15/2022]
Abstract
Microbiota influenced quality formation of ripened Pu-erh tea. To understand the effect of each tea-derived fungal strain, tea-leaves were fermented by Aspergillus pallidofulvus PT-3 (ApaPT), Aspergillus sesamicola PT-4 (AsePT) and Penicillium manginii PT-5 (PmaPT), respectively. 14 Phenolic compounds, 3 purine alkaloids, 19 free amino acids and γ-aminobutyric acid contents were determined by HPLC and amino acid analyzer analysis. Additionally, UHPLC-Q-TOF/MS method was developed for LC-MS metabolomics analysis. Multivariate statistical analyses, such as PCA and HCA, exhibited that the chemical profile of PmaPT fermentation was similar to biocidal treatment, but had significant differences with ApaPT and AsePT fermentation. The differentiated metabolites (VIP > 1, p < 0.05 and FC > 1.50 or < 0.66) and one-way ANOVA revealed the impact of three fungal strains in tea-leaves fermentation. APaPT and AsePT contributed to biosynthesis of gallic acid and several flavonoids, such as kaempferol, quercetin and myricetin in the metabolism of phenolic compounds.
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Affiliation(s)
- Cunqiang Ma
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, Anhui, China; Henan Key Laboratory of Tea Comprehensive Utilization in South Henan, Tea College, Xinyang Agriculture and Forestry University, Xinyang 464000, Henan, China.
| | - Xiaohong Li
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Chengqin Zheng
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Binxing Zhou
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming 650201, Yunnan, China.
| | - Chengcheng Xu
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Tao Xia
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, Anhui, China.
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25
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Doungtip P, Kim KT, Hong H, Ju SE, Choi JW, Siriwoharn T, Prinyawiwatkul W, Sriwattana S. Effects of immersion in fermented tea liquid and steam treatments on physicochemical properties and ginsenoside profiles of Korean ginseng. J FOOD PROCESS PRES 2021. [DOI: 10.1111/jfpp.15050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Kyung Tack Kim
- Division of Strategic Food Technology Korea Food Research Institute Gyeonggi‐do Republic of Korea
| | - Hee‐Do Hong
- Division of Strategic Food Technology Korea Food Research Institute Gyeonggi‐do Republic of Korea
| | - Shin Eun Ju
- Division of Strategic Food Technology Korea Food Research Institute Gyeonggi‐do Republic of Korea
| | - Jae Woong Choi
- Division of Strategic Food Technology Korea Food Research Institute Gyeonggi‐do Republic of Korea
| | | | - Witoon Prinyawiwatkul
- School of Nutrition and Food Sciences Louisiana State University, Agricultural Center Baton Rouge LA USA
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26
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Zhang H, Liu YZ, Xu WC, Chen WJ, Wu S, Huang YY. Metabolite and Microbiome Profilings of Pickled Tea Elucidate the Role of Anaerobic Fermentation in Promoting High Levels of Gallic Acid Accumulation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:13751-13759. [PMID: 33164532 DOI: 10.1021/acs.jafc.0c06187] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Gallic acid (GA) is an important active ingredient for its pharmacological activities. High levels of GA in tea can be obtained by anaerobic fermentation, but its mechanism is still unclear. Here, the profiles of metabolites and microbiomes in pickled tea were analyzed. The results showed that GA of pickled tea increased to 24.26 mg/g at 18 d after anaerobic fermentation, which was accompanied by the reducing levels of epicatechin gallate (ECG), epiafzelechin-3-O-gallate (EAG), and 7-galloylcatechin (7-GC) and the increasing relative abundances of Bacillus and other six bacterial genera. However, epigallocatechin gallate (EGCG) was basically stable during the whole fermentation process. These results suggested that EGCG contributes little to the GA formation during anaerobic fermentation, but ECG, EAG, and 7-GC should be the key precursors to form GA; moreover, bacteria, especially Bacillus, may be responsible for their bioconversion. It will establish an effective way to increase GA in tea production.
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Affiliation(s)
- Huan Zhang
- Ministry of Education Key Laboratory of Horticultural Plant Biology, and Tea Science Department of Horticulture and Forestry Science College, Huazhong Agricultural University, Wuhan City 430070, China
| | - Yong-Zhong Liu
- Ministry of Education Key Laboratory of Horticultural Plant Biology, and Fruit Science Department of Horticulture and Forestry Science College, Huazhong Agricultural University, Wuhan City 430070, China
| | - Wen-Can Xu
- Ministry of Education Key Laboratory of Horticultural Plant Biology, and Tea Science Department of Horticulture and Forestry Science College, Huazhong Agricultural University, Wuhan City 430070, China
| | - Wen-Jun Chen
- Ministry of Education Key Laboratory of Horticultural Plant Biology, and Tea Science Department of Horticulture and Forestry Science College, Huazhong Agricultural University, Wuhan City 430070, China
| | - Shuang Wu
- Ministry of Education Key Laboratory of Horticultural Plant Biology, and Tea Science Department of Horticulture and Forestry Science College, Huazhong Agricultural University, Wuhan City 430070, China
| | - You-Yi Huang
- Ministry of Education Key Laboratory of Horticultural Plant Biology, and Tea Science Department of Horticulture and Forestry Science College, Huazhong Agricultural University, Wuhan City 430070, China
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27
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Assessing Polyphenol Components and Antioxidant Activity during Fermented Assam Tea Ball Processing. SUSTAINABILITY 2020. [DOI: 10.3390/su12145853] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fermented tea is traditionally consumed in many Asian countries. In Thailand, the product is made by anaerobic submerged fermentation of semi-mature tea leaves before being made into a ball form. This study aims to investigate the composition of health-associated bioactive compounds in fermented tea balls made from Camellia sinensis var. assamica, which is naturally grown in the forests of northern Thailand. The processing involves steaming semi-mature tea leaves followed by anaerobic fermentation in 2% NaCl solution (1:5 w/v of tea leaves solution). Levels of catechin (C), epicatechin (EC), epicatechin gallate (ECG), epigallocatechin gallate (EGCG), gallocatechin (GC), flavonols (myricetin, quercetin, and kaempferol), phenolic acids (caffeic acid, chlorogenic acid, coumaric acid, and sinapic acid), total phenolic content, and in vitro antioxidant activity were evaluated in fresh tea leaves, steamed tea leaves, and fermented tea leaves over a period of 60 days’ monitoring. The results indicated that fermented tea balls still contain significant amounts of tea polyphenols, although their processing may result in some loss of most bioactive compounds. The antioxidant activity measured by Ferric Reducing Antioxidant Power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and Oxygen Radical Absorbance Capacity (ORAC) assays also declined as the fermentation time was extended. However, phenolic acids, including caffeic acid and sinapic acid, contrastingly increased during prolonged fermentation by 74.35% and 171.43% from fresh leaves, respectively.
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28
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Li S, Jin Z, Hu D, Yang W, Yan Y, Nie X, Lin J, Zhang Q, Gai D, Ji Y, Chen X. Effect of solid-state fermentation with Lactobacillus casei on the nutritional value, isoflavones, phenolic acids and antioxidant activity of whole soybean flour. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2020.109264] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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29
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Liu M, Xie H, Ma Y, Li H, Li C, Chen L, Jiang B, Nian B, Guo T, Zhang Z, Jiao W, Liu Q, Ling T, Zhao M. High Performance Liquid Chromatography and Metabolomics Analysis of Tannase Metabolism of Gallic Acid and Gallates in Tea Leaves. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:4946-4954. [PMID: 32275834 DOI: 10.1021/acs.jafc.0c00513] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Tannase (E.C. 3.1.1.20) is hypothesized to be involved in the metabolism of gallates and gallic acid (GA) in pu-erh tea fermentation. In this work, we measured tannase in Aspergillus niger fermented tea leaves and confirmed the production of fungal tannase during pu-erh tea fermentation. A decrease in catechin and theaflavin gallates and a significant increase in GA content and the relative peak areas of ethyl gallate, procyanidin A2, procyanidin B2, procyanidin B3, catechin-catechin-catechin, epiafzelechin, and epicatechin-epiafzelechin [variable importance in the projection (VIP) > 1.0, p < 0.05, and fold change (FC) > 1.5] were observed using high performance liquid chromatography (HPLC) and metabolomics analysis of tea leaves fermented or hydrolyzed by tannase. In vitro assays showed that hydrolysis by tannase or polymerization of catechins increased the antioxidant activity of tea leaves. In summary, we identified a metabolic pathway for gallates and their derivatives in tea leaves hydrolyzed by tannase as well as associated changes in gallate and GA concentrations caused by fungal tannase during pu-erh tea fermentation.
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Affiliation(s)
- Mingli Liu
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Haofen Xie
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036 Anhui China
| | - Yan Ma
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Hongye Li
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Chongping Li
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Lijiao Chen
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Bin Jiang
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Bo Nian
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Tianjie Guo
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Zhengyan Zhang
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Wenwen Jiao
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Qianting Liu
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Tiejun Ling
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036 Anhui China
| | - Ming Zhao
- College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China
- State Key Laboratory of Conservation and Utilization of Bio-resources in Yunnan, Yunnan Agricultural University, Kunming, Yunnan 650201, China
- The Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasm Innovation & Utilization of Chinese Medicinal Materials in Southwestern China, Yunnan Agricultural University, Kunming, Yunnan 650201, China
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Tannin-Tolerant and Extracellular Tannase Producing Bacillus Isolated from Traditional Fermented Tea Leaves and Their Probiotic Functional Properties. Foods 2020; 9:foods9040490. [PMID: 32295023 PMCID: PMC7230891 DOI: 10.3390/foods9040490] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 04/07/2020] [Accepted: 04/10/2020] [Indexed: 12/20/2022] Open
Abstract
A total of 117 Bacillus strains were isolated from Miang, a culture relevant fermented tea of northern Thailand. These strains were collected from 16 sampling sites in north Thailand. In this collection 95 isolates were tannin-tolerant Bacillus capable of growth on nutrient agar supplemented with 0.5% (w/v) total tannins from tea leaves extract (TE). The strains were also positive for pectinase, xylanase and amylase activity, while 91 and 86 isolates were positive for cellulase and β-mannanase, respectively. Only 21 isolates producing extracellular tannase were selected for further characterization. Identification by 16S rRNA gene sequence analysis revealed that more than 50% (11 of 21 isolates) were Bacillustequilensis, whereas the remaining were B. siamensis (3), B. megaterium (3), B. aryabhattai (3) and B. toyonensis (1). B. tequilensis K34.2 produced the highest extracellular tannase activity of 0.60 U/mL after cultivation at 37 °C for 48 h. In addition, all 21 isolates were resistant to 0.3% (w/v) bile salt, sensitive to gentamicin, erythromycin, vancomycin and kanamycin and also tolerant to acidic condition. Cell hydrophobicity varied from 9.4 to 80.4% and neutralized culture supernatants of some Bacillus isolates showed bacteriocin producing potentiality against Samonella enterica serovar Typhimurium TISTR 292. All tested probiotic properties indicated that B. tequilensis K19.3, B. tequilensis K34.2 and B. siamensis K19.1 had high probiotic potential. This is the first report describing tannin-tolerant Bacillus and their extracellular tannase producing capability in Miang, a traditional fermented tea of Thailand.
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Xiao Y, Zhong K, Bai JR, Wu YP, Zhang JQ, Gao H. The biochemical characteristics of a novel fermented loose tea by Eurotium cristatum (MF800948) and its hypolipidemic activity in a zebrafish model. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2019.108629] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Production of theophylline via aerobic fermentation of pu-erh tea using tea-derived fungi. BMC Microbiol 2019; 19:261. [PMID: 31771506 PMCID: PMC6878699 DOI: 10.1186/s12866-019-1640-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 11/14/2019] [Indexed: 11/21/2022] Open
Abstract
Background Caffeine is one of the most abundant methylxanthines in tea, and it remains stable in processing of general teas. In the secondary metabolism of microorganism, theophylline is the main conversion product in caffeine catabolism through demethylation. Microorganisms, involved in the solid-state fermentation of pu-erh tea, have a certain impact on caffeine level. Inoculating an appropriate starter strain that is able to convert caffeine to theophylline would be an alternative way to obtain theophylline in tea. The purpose of this study was to isolate and identify the effective strain converting caffeine to theophylline in pu-erh tea, and discuss the optimal conditions for theophylline production. Results Caffeine content was decreased significantly (p < 0.05) and theophylline content was increased significantly (p < 0.05) during the aerobic fermentation of pu-erh tea. Five dominant fungi were isolated from the aerobic fermentation and identified as Aspergillus niger, Aspergillus sydowii, Aspergillus pallidofulvus, Aspergillus sesamicola and Penicillium mangini, respectively. Especially, A. pallidofulvus, A. sesamicola and P. mangini were detected in pu-erh tea for the first time. All isolates except A. sydowii TET-2, enhanced caffeine content and had no significant influence on theophylline content. In the aerobic fermentation of A. sydowii TET-2, 28.8 mg/g of caffeine was degraded, 93.18% of degraded caffeine was converted to theophylline, and 24.60 mg/g of theophylline was produced. A. sydowii PET-2 could convert caffeine to theophylline significantly, and had application potential in the production of theophylline. The optimum conditions of theophylline production in the aerobic fermentation were 1) initial moisture content of 35% (w/w), 2) inoculation quantity of 8%, and 3) incubation temperature at 35 °C. Conclusions For the first time, we find that A. sydowii PET-2 could convert caffeine to theophylline, and has the potential value in theophylline production through aerobic fermentation.
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Shi J, Zhu Y, Zhang Y, Lin Z, Lv HP. Volatile composition of Fu-brick tea and Pu-erh tea analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry. Lebensm Wiss Technol 2019. [DOI: 10.1016/j.lwt.2018.12.075] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Mao A, Su H, Fang S, Chen X, Ning J, Ho C, Wan X. Effects of roasting treatment on non-volatile compounds and taste of green tea. Int J Food Sci Technol 2018. [DOI: 10.1111/ijfs.13853] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Ajing Mao
- State Key Laboratory of Tea Plant Biology and Utilization; Anhui Agricultural University; 130 Changjiang Blvd West Hefei 230036 China
| | - Huan Su
- State Key Laboratory of Tea Plant Biology and Utilization; Anhui Agricultural University; 130 Changjiang Blvd West Hefei 230036 China
| | - Shimao Fang
- State Key Laboratory of Tea Plant Biology and Utilization; Anhui Agricultural University; 130 Changjiang Blvd West Hefei 230036 China
| | - Xu Chen
- School of Tea and Food Science and Technology; Anhui Agricultural University; 130 Changjiang Blvd West Hefei 230036 China
| | - Jingming Ning
- State Key Laboratory of Tea Plant Biology and Utilization; Anhui Agricultural University; 130 Changjiang Blvd West Hefei 230036 China
| | - Chitang Ho
- Department of Food Science; Rutgers University; New Brunswick NJ USA
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization; Anhui Agricultural University; 130 Changjiang Blvd West Hefei 230036 China
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Bouphun T, Wei X, Dan W, Zhao R, Qi Z. Dynamic Changes in Chemical Constituents during Processing of Miang (Thai Fermented Tea Leaf) in Various Degree of Tea leaf Maturity. ACTA ACUST UNITED AC 2018. [DOI: 10.18178/ijfe.4.3.178-185] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Diversity of lactic acid bacteria from Miang, a traditional fermented tea leaf in northern Thailand and their tannin-tolerant ability in tea extract. J Microbiol 2017; 55:720-729. [PMID: 28865074 DOI: 10.1007/s12275-017-7195-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 08/08/2017] [Accepted: 08/11/2017] [Indexed: 01/30/2023]
Abstract
The microbiota of lactic acid bacteria (LAB) in thirty-five samples of Miang, a traditional fermented tea leaf product, collected from twenty-two different regions of eight provinces in upper northern Thailand was revealed through the culture-dependent technique. A total of 311 presumptive LAB strains were isolated and subjected to clustering analysis based on repetitive genomic element-PCR (rep-PCR) fingerprinting profiles. The majority of the strains belonged to the Lactobacillus genera with an overwhelming predominance of the Lb. plantarum group. Further studies of species-specific PCR showed that 201 of 252 isolates in the Lb. plantarum group were Lb. plantarum which were thus considered as the predominant LAB in Miang, while the other 51 isolates belonged to Lb. pentosus. In contrast to Lb. plantarum, there is a lack of information on the tannase gene and the tea tannin-tolerant ability of Lb. pentosus. Of the 51 Lb. pentosus isolates, 33 were found to harbor the genes encoding tannase and shared 93-99% amino acid identity with tannase obtained from Lb. pentosus ATCC 8041T. Among 33 tannase gene-positive isolates, 23 isolates exhibited high tannin- tolerant capabilities when cultivated on de Man Rogosa and Sharpe agar-containing bromocresol purple (0.02 g/L, MRS-BCP) supplemented with 20% (v/v) crude tea extract, which corresponded to 2.5% (w/v) tannins. These Lb. pentosus isolates with high tannin-tolerant capacity are expected to be the high potential strains for functional tannase production involved in Miang fermentation as they will bring about certain benefits and could be used to improve the fermentation of tea products.
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Yao Y, Wu M, Huang Y, Li C, Pan X, Zhu W, Huang Y. Appropriately raising fermentation temperature beneficial to the increase of antioxidant activity and gallic acid content in Eurotium cristatum -fermented loose tea. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2017.04.032] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Wang L, Bei Q, Wu Y, Liao W, Wu Z. Characterization of soluble and insoluble-bound polyphenols from Psidium guajava L. leaves co-fermented with Monascus anka and Bacillus sp. and their bio-activities. J Funct Foods 2017. [DOI: 10.1016/j.jff.2017.02.029] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico Studies. Molecules 2016; 21:molecules21101346. [PMID: 27754346 PMCID: PMC6273586 DOI: 10.3390/molecules21101346] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 09/28/2016] [Accepted: 10/06/2016] [Indexed: 12/16/2022] Open
Abstract
Teas can be classified according to their degree of fermentation, which has been reported to affect both the bioactive components in the teas and their antioxidative activity. In this study, four kinds of commercial Taiwanese tea at different degrees of fermentation, which include green (non-fermented), oolong (semi-fermented), black (fully fermented), and Pu-erh (post-fermented) tea, were profiled for catechin levels by using high performance liquid chromatography (HPLC). The result indicated that the gallic acid content in tea was directly proportional to the degree of fermentation in which the lowest and highest gallic acid content were 1.67 and 21.98 mg/g from green and Pu-erh tea, respectively. The antioxidative mechanism of the gallic acid was further determined by in vitro and in silico analyses. In vitro assays included the use of phorbol ester-induced macrophage RAW264.7 cell model for determining the inhibition of reactive oxygen species (ROS) production, and PKCδ and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit (p47) activations. The results showed that only at a concentration of 5.00 μM could gallic acid significantly (p < 0.05) reduce ROS levels in phorbol ester-activated macrophages. Moreover, protein immunoblotting expressed similar results in which activations of PKCδ and p47 were only significantly (p < 0.05) attenuated by 5.00 μM treatment. Lastly, in silico experiments further revealed that gallic acid could block PKCδ activation by occupying the phorbol ester binding sites of the protein.
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