JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2020
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IF 4.192
Zhongyu Li,Yan Mao,Jianwen Teng,Ning Xia,Li Huang,Baoyao Wei,Qingjin Chen
Citrinin (CIT), a known nephrotoxic mycotoxin, is mainly produced by Penicillium, Aspergillus, and Monascus species. It is a natural contaminant in cereal grains, foods, and feedstuff. Liupao tea (or Liubao tea) is a typical Chinese dark tea obtained via indigenous tea fermentation facilitated by microorganisms. Certain fungi present in Liupao tea that may produce CIT are a potential threat to consumer health. In the present study, various potential toxigenic mycoflora and the natural occurrence of CIT in Liupao tea were surveyed via the culture-dependent method, high performance liquid chromatography–fluorescence detection (HPLC–FLD), and ultrahigh performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). Total mold counts ranged from 3.5 × 102 CFU/g to 2.1 × 106 CFU/g tea in 28 tea samples. A total of 218 fungal isolates belonging to five genera and 23 species were identified. Some of these strains, such as Aspergillus ochraceus, Aspergillus oryzae, Penicillium citrinum, and Penicillium chrysogenum, may potentially be a CIT-producing species. In addition, 32.7% of 113 Liupao tea samples were contaminated with CIT at concentrations ranging from 7.8 to 206.1 μg/kg. These CIT concentrations in Liupao tea are chiefly attributed to climatic conditions and water activity during storage that favor fungal proliferation and mycotoxin production. However, CIT could not be detected in Liupao tea stored for over 10 years. These results provide the first information about the potential toxigenic mycoflora and natural occurrence of CIT in Liupao tea. Therefore, storage conditions and fungal community must be monitored to ensure the quality of Liupao tea.
研究领域:
食品安全
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微生物学
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植物学
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DOI
PubMed
高影响因子
Food Bioscience
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2019
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IF 3.22
Weilu Guo,Mouming Zhao,Qingjin Chen,Li Huang,Yan Mao,Ning Xia,Jianwen Teng,Baoyao Wei
The ability of a strain to produce citrinin was analysed in the growth inhibition zone using HPLC and UHPLC–MS. A total of 12 Penicillium citrinum strains isolated from Liupao tea were inoculated onto tea leaves and their capability for citrinin production were studied using different water content (15–45%) and temperatures (15–40 °C). The results provided a theoretical base for the safe manufacture of Liupao tea. Five strains of P. citrinum produced a clear growth inhibition zone with diameters of 11–22 mm. The citrinin contents in the liquid cultures of the 12 strains of P. citrinum ranged from 0.03 to 14.5 μg/mL. The citrinin contents of the teas with initial water content of 15 and 25% and those inoculated with P. citrinum were below the limit of detection during the fermentation. The citrinin content of the teas with initial water contents of 35 and 45% at 25 °C increased rapidly at first and then decreased during the fermentation. Similarly, the citrinin contents of the teas at 15 and 25 °C rapidly increased and then decreased. Meanwhile, P . citrinum was unable to produce citrinin at 35 and 40 °C. The optimum conditions were 45% water and 25 °C, generating the highest citrinin yield of 181 ng/g, which was higher than the limit of 50 ng/g citrinin in red yeast rice that can cause harm to human health. The highest citrinin yield in tea fermented for 50 days was 34.8 ng/g for stored teas with proper conditions. Therefore, storing teas with a low water content and temperature can reduce the content of citrinin.
研究领域:
食品科学
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微生物学
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DOI
高影响因子
Food Chemistry-X
·
2024
·
IF 6.5
Jianfeng Liang,Hailin Wu,Mingfei Lu,Ya Li
This study used headspace solid-phase microextraction-gas chromatography–mass spectrometry and multivariate statistical analysis to comprehensively analyze the volatile components in Liupao tea samples throughout fermentation. In total, 1009 volatile organic compounds were detected and identified, including terpenoids, heterocyclic compounds, esters, ketones, hydrocarbons, alcohols, aromatics, and acids. Principal component and hierarchical cluster analyses, characterize the volatile components of Liupao tea samples were characterized at various fermentation stages. Orthogonal partial least squares discriminant analysis identified 248 differentiating compounds (VIP ≥ 1, P < 0.05, and |Log 2 FC| ≥ 1.0) during fermentation. K-means clustering analysis showed that 11 metabolites increased significantly throughout the fermentation process, whereas 31 metabolites decreased continuously. Annotation of these differential compounds revealed significant changes in sensory flavor characteristics in “green, sweet, fruity, floral, and woody” flavors. The results demonstrated significant variations in the volatile components of Liupao tea fermentation, along with notable changes in flavor characteristics.
研究领域:
食品科学
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分析化学
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植物代谢
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2024
·
IF 8.5
Yueming Liang,Zhusheng Liu,Yuelan Pang,Min Li,Shengmeng Zheng,Fujing Pan,Chunyu Guo,Qianhua Wu,Ting Chen,Qiang Li,Zhonghua Liu
Long-term storage of Liupao tea is conducive to improving its flavour and commercial value. Although bacterial communities influence Liupao tea flavour, their impact during storage remains unclear. The aroma compounds and bacterial communities were determined by headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC–MS) and Illumina Nova6000 analysis. A total of 18 differential flavour compounds were significantly altered with Liupao tea storage duration, particularly after 9 years of storage. Flavour compounds with sweet notes increased, while those associated with pungent note decreased. The composition and diversity of bacteria remarkable changed after 9 years of tea storage. Six core functional bacteria were identified as contributing to the flavour characteristics of Liupao tea during long-term storage. Our findings provide novel insights that bacteria drive the formation of flavour characteristics during Liupao tea storage duration, and Liupao tea stored for more than 9 years have the best flavour.
研究领域:
食品科学
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微生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD SCIENCE AND TECHNOLOGY-MYSORE
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2024
·
IF 2.6
Li Ya,Liang Jianfeng,Liang Lili
Pile fermentation plays a crucial role in the formation of the unique flavor of Liupao tea, which can effectively reduce the bitterness of the tea and promote the formation of red tea soup. In this study, the non-volatiles changes of Liupao tea during pile fermentation processing were fully analyzed by UPLC-QTOF-MS/MS. A total of 271 metabolites with significant differences were identified in Liupao tea during pile fermentation( P < 0.01, VIP > 1), and their trends were grouped into 10 subclasses by K-means analysis. Three differential metabolites Choline Alfoscerate, N1-Methyl-4-pyridone-5-carboxamide, and 2-Aminovalienone were shared among the three different pile fermentation periods. The results provided valuable information for understanding the dynamic changes of non-volatile substances during the pile fermentation process of Liupao tea.
研究领域:
食品科学
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代谢组学
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产品关联
DOI
PubMed
高影响因子
FUNGAL GENETICS AND BIOLOGY
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2022
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IF 3.883
Jiazhen Qin,Jianwen Teng,Zhongyu Li,Ning Xia,Baoyao Wei,Li Huang
Similar to Pu-erh tea, Liupao tea is a post-fermented tea that is produced through natural fermentation by microorganisms. Penicillium citrinum is involved in multiple production processes of Liupao tea that can produce citrinin, a secondary metabolite with renal toxicity; however, the effect of P. citrinum on the quality of Liupao tea has not been investigated yet. Citrinin production is regulated by approximately 16 biosynthesis genes. However, little is known about the genetic background of citrinin in the complex Liupao tea system. In the present study, we cultured P. citrinum on potato dextrose agar and Liupao tea powder media and analyzed the changes of its nutritional components in Liupao tea. We selected six citrinin biosynthesis genes identified in Monascus exhibiting homology and high sequence similarity to those in P. citrinum and further analyzed the expression of citrinin biosynthesis genes in Liupao tea and the changes in citrinin yield. The results showed that the changes in nutritional components of Liupao tea were closely related to the growth and metabolism of P. citrinum and the quality of the tea. Decreases in the contents of soluble sugars (from 10.29% to 9.58%), soluble pectins (from 3.71% to 3.13%), free amino acids (from 3.84% to 3.14%), and tea polyphenols (from 22.84% to 18.78%) were noted. The Spearman’s correlation analysis indicated that P. citrinum growth can improve the tea quality to some extent. Quantitative real-time PCR demonstrated that ctnA gene was a positive regulator of citrinin production regardless of the culture medium used. ctnA and orf5 expressions greatly influenced the metabolism of citrinin by P. citrinum in Liupao tea. In conclusion, the citrinin biosynthesis genes, ctnA and orf5 , may be the promising targets for developing strategies to control P. citrinum infection and citrinin biosynthesis in Liupao tea.
研究领域:
食品科学
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微生物学
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分子生物学
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制茶技术
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DOI
PubMed
高影响因子
Heliyon
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2024
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IF 3.4
Huazhen Huo,Aihua Cai,Yunchang Xie,Chunyu Guo
Purpose Piling is a critical process for the formation of raw Liupao tea (RLT) flavor quality. However, given the unclear changes in the flavor quality of RLT during the piling process, and the key substances of taste-contributing and aroma components that affecting the flavor quality of RLT was lacking. Herein, the present study aimed at evaluating the changes in flavor quality and its key substances of RLT during the piling process. Methods Sensory evaluation was conducted on RLT samples collected at 11 time points during the piling process. The biochemical and aroma components of these samples were detected using UV spectrophotometer, high-performance liquid chromatography (HPLC), and headspace solid-phase microextraction gas chromatography–mass spectrometer (HS-SPME-GC-MS), respectively. Multivariate analysis was performed to investigate the effects of piling time on the flavor quality of RLT. Key findings The sensory quality of RLT increased and then decreased during the piling process. The changes in flavor quality of RLT during the piling process could be divided into four stages: 0–6, 9–15, 18–24, and 27–30 h. The flavor quality of RLT changed significantly with the variations in biochemical and volatile compounds. The key contributors to taste changes included significant decreases in (−)-epigallocatechin gallate, (−)-epicatechin gallate, (−)-epigallocatechin, (−)-catechin gallate, and theobromine content and significant increases in gallic acid, gallocatechin, and theaflavin content. Additionally, alterations in the content of 19 characteristic aroma compounds, such as cedrol, methyl salicylate, methyl palmitate, trans-nerolidol, decanal, 6,10-Dimethyl-2-undecanone, neryl alcohol, α -cedrene, and (E, E)-2,4-heptadienal, significantly influenced the aroma of the tea infusion. This study provides insights into the formation of flavor quality in RLT at different piling stages, which also provide a scientific foundation for optimizing the piling and production processes of RLT.
研究领域:
食品科学
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茶叶学
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分析化学
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产品关联
DOI
PubMed
高影响因子
Food & Function
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2023
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IF 6.1
Su Zhou,Zhelu Bao,Shicheng Ma,Cansong Ou,Hao Hu,Yunyun Yang,Xinyu Feng,Yani Pan,Shuying Gong,Fangyuan Fan,Ping Chen,Qiang Chu
The prevalence of oral health problems is ubiquitous in contemporary society, with particular emphasis placed on the central role of oral flora in mitigating this issue. Both ancient literature and modern research have highlighted the promising application of tea with substantial bioactive properties, particularly dark tea, in preserving and promoting oral health. Liubao tea, a widely consumed dark tea with increasing popularity in recent years, has been reported to possess abundant bioactive constituents, exhibit remarkable antioxidant and anti-inflammatory effects, modulate the flora structure and so on. It may be a promising candidate for addressing oral health problems. In this study, Liubao tea was meticulously extracted, purified and identified, followed by an investigation of its potential to modulate oral microecology by virtue of an acetic acid-induced oral disorder murine model. The results revealed that Liubao tea extract (LTE) application commendably reconstructed the oral mucosal barrier, promoted tissue regeneration and mitigated micro-inflammation. Furthermore, LTE treatment could also ameliorate the oral flora composition by decreasing the abundance of Proteobacteria and increasing the abundance of Firmicutes and Actinobacteria at the phylum level, as well as inhibiting pernicious bacteria such as Streptococcus and Delftia acidovorans. So, it could promote the generation of a beneficial microenvironment and regulate the immune process. Overall, LTE demonstrated remarkable potential in regulating the balance of oral microecology, suggesting that it may represent a promising therapeutic strategy for oral health concerns.
研究领域:
牙科学
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微生物学
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药理学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Wenkai Zhang,Wei Chen,Hongjing Pan,Alireza Sanaeifar,Yan Hu,Wanghong Shi,Jie Guo,Lejia Ding,Jihong Zhou,Xiaoli Li,Yong He
Identifying the aging time of Liu-Pao Tea (LPT) presents a persistent challenge. We utilized an AI-Multimodal fusion method combining FTIR, E -nose, and E-tongue to discern LPT's aging years. Compared to single-source and two-source fusion methods, the three-source fusion significantly enhanced identifying accuracy across all four machine learning algorithms (Decision tree, Random forest, K-nearest neighbor, and Partial least squares Discriminant Analysis), achieving optimal accuracy of 98–100 %. Physicochemical analysis revealed monotonic variations in tea polysaccharide (TPS) conjugates with aging, observed through SEM imaging as a transition from lamellar to granular TPS conjugate structures. These quality changes were reflected in FTIR spectral characteristics. Two-dimensional correlation spectroscopy (2D-COS) identified sensitive wavelength regions of FTIR from LPT and TPS conjugates, indicating a high similarity in spectral changes between TPS conjugates and LPT with aging years, highlighting the significant role of TPS conjugates variation in LPT quality. Additionally, we established an index for evaluating quality of aging, which is sum of three fingerprint peaks (1029 cm −1 , 1635 cm −1 , 2920 cm −1 ) intensities. The index could effectively signify the changes in aging years on macro-scale (R 2 = 0.94) and micro-scale (R 2 = 0.88). These findings demonstrate FTIR's effectiveness in identifying aging time, providing robust evidence for quality assessment.
研究领域:
食品科学
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化学计量学
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光谱学
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人工智能
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分析化学
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
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2024
·
IF 2.7
Xuancheng Wang,Zhiyong She,Hailin Zhou,Tingting An,Jianwen Teng,Ning Xia,Pingchuan Zhu,Wenhui Liu,Huanxiao Dong,Limin Tang,Shulan You,Lu Wei,Kongying Li,Lingli Wang,Li Huang,Qisong Zhang
Liupao tea (LPT) is a Chinese dark tea known to possess a unique flavour. Microbial fermentation plays a crucial role in flavour development and enrichment. Currently, the phytochemical profiles and bioactivities of LPT with and without fermentation are not fully known. In this study, we compared the chemical composition of raw tea (SF), stale-aroma (SA), and betelnut-aroma (BA) type LPT through the application of GC/LC-MS-based metabolomics, and experimentally investigated their bioactivities via antioxidant, anti-inflammatory, hypolipidemic, and hypoglycemic assays in vitro. The results indicated that fermentation enhanced the flavour of LPT as evidenced by the sweetness-producing substances, decreased bitterness and astringency-related compounds and enriched abundance of aroma-generating compounds. Two and four volatiles were detected to be major contributors to the aroma in SA and BA, respectively. Fatty acids and phosphatidylcholines were the primary lipids, among which the lysing diacylglycerol trimethyl homoserines were found to be a new class of lipids in LPT. Notably, the fermentation resulted in the degradation of compounds, particularly glycerophospholipids and saccharolipids. SF had the highest level of bioactivity, followed by BA and SA. These findings expand the present understanding regarding the development of flavour, nutrition, and medicinal value of LPT. Moreover, they provide a theoretical basis for the identification of BA and SA and serve as a reference value for consumers in their selection of LPT products.
研究领域:
食品科学
·
药理学
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代谢组学
·
茶叶科学
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产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
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2023
·
IF 8.1
Yingyi Huang,Huahong Liu,Xiaohua Zhang,Yuxin Wu,Zhusheng Liu,Yuelan Pang,Renjun Liu,Chun Yang,Jinfang Nie
Long-term storage of Liupao tea (LPT) is usually believed to enhance its quality and commercial value. The non-volatile metabolites variations and the fungal succession play a key role for organoleptic qualities during the storage procedure. To gain in-depth understanding the impact of storage time on the quality of LPT, two different brands of LPT with different storage time, including Maosheng LPTs (MS) with 0, 5, 10 and 15 years and Tianyu LPTs (TY) with 0, 3, 5, 8 and 10 years, were resorted to investigate the changes of non-volatile metabolites and fungi as well as their correlation by multi-omics. A total of 154 and 119 differential metabolites were identified in these two different brands of MS and TY, respectively, with the aid of high-performance liquid chromatography with quadrupole-time-of-flight mass spectrometry. In both categories of LPTs, the transformation of differential metabolites in the various stages referred to the formation of alkaloids, increase of organic acids, biosynthesis of terpenoids as well as glycosylation and methylation of flavonoids. Thereinto, glycosylation and methylation of flavonoids were the critical stages for distinguishing MS and TY, which were discovered in MS and TY stored for about 10 and 8 years, respectively. Moreover, the results of high-throughput sequencing showed that the key fungal genera in the storage of LPTs consisted of Eurotium , Aspergillus , Blastobotrys , Talaromyces , Thermomyces and Trichomonascus . It was confirmed on the basis of multivariate analysis that the specific fungal genera promoted the transformation of metabolites, affecting the tea quality to some extent. Therefore, this study provided a theoretical basis for the process optimization of LPT storage.
研究领域:
食品科学
·
微生物学
·
代谢组学
·
茶叶科学
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产品关联
DOI
PubMed
高影响因子
PHYTOMEDICINE
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2024
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IF 6.7
Shanyi Yang,Zhijuan Wei,Jichu Luo,Xuancheng Wang,Guanghui Chen,Xuan Guan,Zhiyong She,Wenhui Liu,Ying Tong,Huan Liu,Mingsen Wen,Hongwei Chen,Pingchuan Zhu,Gui Li,Dongling Wang,Lin Huang,Siyi Xu,Danying Chen,Qisong Zhang,Ye Wei
Background Non-alcoholic fatty liver disease (NAFLD) poses a significant global public health concern. Liupao tea (LPT) is a Chinese national geographical indication product renowned for its lipid-lowering properties. However, the precise mechanisms and active constituents contributing to the efficacy of LPT against NAFLD remain unclear. Purpose This study aims to comprehensively explore the therapeutic potential of Liupao tea extract (LPTE) in alleviating NAFLD through an integrated strategy. Methods Initially, network pharmacology analysis was conducted based on LPTE chemical ingredient analysis, identifying core targets and key components. Potential active ingredients were validated through chemical standards based on LC-MS/MS. To confirm the pharmacological efficacy of LPTE in NAFLD, NAFLD mice models were employed. Alterations in hepatic lipid metabolism were comprehensively elucidated through integration of metabolomics, lipidomics, network pharmacology analysis, and real-time PCR analysis. To further explore the binding interactions between key components and core targets, molecular docking and microscale thermophoresis (MST) analysis were employed. Furthermore, to investigate LPTE administration effectiveness on gut microbiota in NAFLD mice, a comprehensive approach was employed. This included Metorigin analysis, 16S rRNA sequencing, molecular docking, and fecal microbiome transplantation (FMT). Results Study identified naringenin, quercetin, luteolin, and kaempferol as the potential active ingredients of LPTE. These compounds exhibited therapeutic potential for NAFLD by targeting key proteins such as PTGS2, CYP3A4, and ACHE, which are involved in the metabolic pathways of hepatic linoleic acid (LA) and glycerophospholipid (GP) metabolism. The therapeutic effectiveness of LPTE was observed to be comparable to that of simvastatin. Furthermore, LPTE exhibited notable efficacy in alleviating NAFLD by influencing alterations in gut microbiota composition ( Proteobacteria phylum, Lactobacillus and Dubosiella genus) that perhaps impact LA and GP metabolic pathways. Conclusion LPTE could be effective in preventing high-fat diet (HFD)-induced NAFLD by modulating hepatic lipid metabolism and gut microbiota. This study firstly integrated bioinformatics and multi-omics technologies to identify the potential active components and key microbiota associated with LPTE's effects, while also primally elucidating the action mechanisms of LPTE in alleviating NAFLD. The findings offer a conceptual basis for LPTE's potential transformation into an innovative pharmaceutical agent for NAFLD prevention.
研究领域:
药理学
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生物信息学
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代谢组学
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脂质组学
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胃肠病学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）