FOOD RESEARCH INTERNATIONAL
·
2020
·
IF 4.972
Chao Wang,Zhongrong He,Chenxia Zhang,Liping Du,Dongguang Xiao,Yongquan Xu
The objective of this study was to identify the released behavior of odor-active compounds of Pu-erh tea during the water-boiling extraction, as well as to explore the feasibility of aroma recovery using absorption oils. The behavior of odor-active compounds was identified by using piecewise recovered condensed water combined with sensory, GC-O, and GC–MS analysis. The power-function type kinetic model was the model that best fitted odor intensities, alcohols, methoxy-phenolics, esters, aldehydes, ketones, and total compounds of condensed water. The sensory quality of the condensed water was the best when 16% of added water was evaporated. Six absorption oils were evaluated, and paraffin oil (35 cSt) performed the best in terms of both absorption efficiency and sensory quality of the essential oil. Under the optimized conditions, the absorption and recovery efficiency of odor compounds reached 54.49% and 39.52%, respectively. The alcohols, aldehydes, and methoxy-phenolics exhibited higher absorption and recovery efficiency.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2020
·
IF 4.006
Xiaoqin Wang,María del Mar Contreras,Dunming Xu,Chen Xing,Lijuan Wang,Daomao Yang
Bound phenolic compounds have been widely investigated in food from plants, while research on vegetable oils is limited. Thus, to comparatively analyse free and bound phenolic compounds in a lipid system, different distributions of free and bound phenolic compounds were prepared by exogenous addition of chemical standards to model tea seed oil in this work. For that, the phenolic composition was quantified with UHPLC-QqQ-MS/MS, and the antioxidant capacity was evaluated by the DPPH assay and the Rancimat method. After pre-optimisation of concentrations, the results showed that the oil sample contained 12.3% bound phenolic compounds after incubation for 6 h, higher than the other samples (0, 2, 4, 8, 10 and 12 h) with equal addition. This sample also had a longer reduction time during Rancimat oxidation, corresponding to the higher total DPPH radical scavenging capacity. Further, docking, molecular dynamics and quantum mechanics analysis revealed that intermolecular forces might account for binding forms between phenolic compounds and glycerides, including hydrogen bonds and hydrophobic interactions. In addition, the structure-activity relationship of bound phenolic compounds was explored tentatively. Conclusively, bound phenolic compounds in vegetable oil, probably formed by intermolecular interactions, enhanced antioxidant capacity, a novel perspective on the antioxidation in lipids.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 67
·39272-39281
·
IF 3.049
Xiaodong Huang,Yanan Liu,Huifang Liu,Guangyang Liu,Xiaomin Xu,Lingyun Li,Jun Lv,Haixiang Gao,Donghui Xu
A simple, sensitive, and reliable magnetic solid-phase extraction (SPE) method coupled with GC-MS/MS for the effective analysis of four pyrethroids from tea infusions was developed. A magnetic adsorbent, named ionic liquid-modified magnetic zeolitic imidazolate framework-8 (Fe3O4/ZIF-8/IL), was prepared by immobilizing an ionic liquid (IL) on the surface of Fe3O4/ZIF-8. The textures of Fe3O4/ZIF-8/IL were confirmed by material characterization, and the results suggested that the adsorbent possessed high magnetism (59.0 emu g−1), an adequate Brunauer–Emmett–Teller (BET) surface area (104 m2 g−1), and a large pore volume (0.68 cm3 g−1). To confirm the extraction performance of the prepared Fe3O4/ZIF-8/IL, several experimental conditions affecting the extraction efficiency were investigated. Under the optimum conditions, the limits of determination (LODs) for the four pyrethroids were in the range of 0.0065–0.1017 μg L−1 (S/N = 3 : 1) with an intra-day relative standard deviation (RSD) of ≤9.70% and inter-day RSD of ≤11.95%. The linear ranges were 0.5–50 μg L−1 for bifenthrin and 0.5–500 μg L−1 for permethrin, cypermethrin, and flucythrinate, with determination coefficients higher than 0.999. Finally, the proposed technique was successfully applied for the determination of pyrethroids in real tea infusions. This work could be extended to other IL-modified metal–organic frameworks (MOFs) and to the development of different sample pretreatment techniques.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2020
·
IF 4.389
Fan Gao,Hongjun Zhou,Zhichuan Shen,Guowei Zhu,Li Hao,Huayao Chen,Hua Xu,Xinhua Zhou
Tea tree oil (TTO) is an efficient natural antibacterial agent. However, the bacteriostatic effect of TTO does not prevail for a long period because of the volatile nature of the oil. Therefore, a novel sustained-release formulation of TTO should be developed for improving the applicability of TTO. Herein, the mesoporous silica was selected for constructing a carrier for TTO. Mesoporous silica is non-toxic, easy to modify and exhibited an adjustable pore size. First, the mesoporous silica was modified by an aminated silane coupling agent (NH 2 -MCM-41). Then, the polyacrylic acid (PAA) was bonded by electrostatic bonds (PAA-NH 2 -MCM-41), which imparted the sustained-release effect in the TTO, supported in the mesoporous silica channel (TTO/PAA-NH 2 -MCM-41). The prepared bacteriostatic agent can achieve long-term sustained-release properties. At room temperature (26 ℃), the release rate of TTO after 11 h release reached 50 %. However, the release rate of TTO from TTO/PAA-NH 2 -MCM-8 reached only 42 % after 24 h. Furthermore, the sustained release behavior of TTO/PAA-NH 2 -MCM-41 was consistent with the Korsmeyer-Peppas kinetic model. Compared to TTO, TTO/PAA-NH 2 -MCM-41 exhibited a stable and sustained bacteriostatic effect even after 50 days in a natural environment. The minimum inhibitory concentration (MIC) value of the TTO/PAA-NH 2 -MCM-41 against Escherichia coli ( E. coli ) was 0.37∼0.44 mg/mL. TTO altered the cell morphology of E. coli and broke the integrity of the cell membrane, leading to cell death.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Lu Wang,You Luo,Yanan Wu,Yan Liu,Zhenqiang Wu
There are both soluble and insoluble-bound forms of phenolics in tea-leaf products. In order to increase total soluble phenolics contents, guava leaves tea (GLT) was first fermented with Monascus anka and Saccharomyces cerevisiae , and then hydrolyzed with complex enzymes . The changes in phenolics profiles, antioxidant activities and inhibitory effect on α -glucosidase in processed GLT were investigated. Compared with the un-fermented GLT, fermentation and complex enzymatic processing (FE) significantly increased the total phenolics, total flavonoids, quercetin and kaempferol contents by 2.1, 2.0, 13.0 and 6.8 times, respectively. After the FE, a major proportion of phenolics existed in the soluble form. Quercetin was released in the highest amount among different phenolics. In addition, soluble phenolic extracts from GLT following FE exhibited a highest antioxidant activity and inhibitory effect on α -glucosidase. The paper suggested an improved method for processing GLT into high-value products rich in phenolics and flavonoids aglycones with enhanced health benefits.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Microbiology
·
2018
·
IF 4.019
Lu Qinhua,Wang Yuchun,Li Nana,Ni Dejiang,Yang Yajun,Wang Xinchao
Colletotrichum, the causative agent of anthracnose, is an important pathogen that invades the tea plant (Camellia sinensis). In this study, 38 isolates were obtained from the diseased leaves of tea plants collected in different areas of Zhejiang Province, China. A combination of multigene (ITS, ACT, GAPDH, TUB2, CAL, and GS) and morphology analyses showed that the 38 strains belonged to two different species, namely, C. camelliae (CC), and C. fructicola (CF). Pathogenicity tests revealed that CC was more invasive than CF. In vitro inoculation experiments demonstrated that CC formed acervuli at 72 hpi and developed appressoria on wound edges, but CF did not develop these structures. Under treatment with catechins and caffeine, the growth inhibition rates of CF were remarkably higher than those of CC, indicating that the nonpathogenic species CF was more vulnerable to catechins and caffeine. Growth condition testing indicated that CF grew at a wide temperature range of 15–35°C and that the optimum temperature for CC growth was 25°C. Growth of both CC and CF did not differ between acidic and weakly alkaline environments (pH 5–8), but the growth of CC was significantly reduced at pH values of 9 and 10. Furthermore, the PacC/RIM101 gene, which associated with pathogenicity, was identified from CC and CF genomes, and its expression was suppressed in the hyphae of both species under pH value of 5 and 10, and much lower expression level was detected in CC than that in CF at pH 6. These results indicated that temperature has more important effect than pH for the growth of two Colletotrichum species. In conclusion, the inhibition by secondary metabolite is an important reason why the pathogenicity by CC and CF are different to tea plant, although the environmental factors including pH and temperature effect the growth of two Colletotrichum species.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Ying Zhou,Qiyuan Peng,Lanting Zeng,Jinchi Tang,Jianlong Li,Fang Dong,Ziyin Yang
After tea leaves, tea ( Camellia sinensis ) flowers are becoming a second tea plant resource because they contain not only functional metabolites similar to those found in tea leaves, but also predominant amounts of functional metabolites that only occur in tea leaves in small amounts. 1-Phenylethanol (1PE) is a predominant aroma compound found in tea flowers. A 1PE synthase in tea flowers was isolated, functionally characterized, and shown to have the highest catalytic efficiency for the conversion of acetophenone (AP). To determine why 1PE accumulates more in tea flowers than other plants, we compared their 1PE contents and used a stable isotope labeling method to elucidate the 1PE biosynthetic route. Supplementation with [ 2 H 8 ] l -phenylalanine and [ 2 H 5 ]AP suggested that most plants containing the enzyme/gene catalyzed the conversion of AP to 1PE. Furthermore, the availability of AP derived from l -phenylalanine was responsible for the difference in 1PE accumulation between tea flowers and other plants.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOTECHNOLOGY AND BIOPROCESS ENGINEERING
·
2015
·Vol. 20
·期 1
·157-167
·
IF 1.113
Chaudhary Narendra,Bhardwaj Jyoti,Hwang Jae-Ho,Seo Hyo-Jin,Kim Min-Yong,Shin Tai-Sun,Wee Ji-Hyang,Shin Yu-Lim,Kim Jong-Deog
Camellia sinensis L. O. Kuntze has traditionally been used in Asian countries as a stimulant, a diuretic, and to prevent obesity. Studies in green tea are well-documented in literature, though the potential of fruit from the plant has never been studied in details. In the present study, the anti-adipogenic effect of aqueous extract of green tea seed cake extract (GTE) were analysed in-vitro and the anti-obesity effects were determined in-vivo in murine model fed high-fat and high-carbohydrate diets. We found that GTE inhibited the lipid accumulation in 3T3-L1 adipocyte and significantly lowered body weight, body fat-pad weights, blood lipid, glucose, insulin, and leptin levels in mice fed high-fat and high-carbohydrate diets. GTE suppressed the expression of important adipogenic genes (PPARγ, C/EBPα, SREBP, LPL, aP2 and leptin) and lipid metabolism genes (FAS). Furthermore, GTE induced the levels of adiponectin in serum and adipose tissue, as well as AMP-activated protein kinase (AMPK) in liver tissue. These results suggested that GTE ameliorates its anti-obesity effect through multiple cells signaling pathways in diets induced obesity in mice.
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Zifan Hu,Weiyang Sun,Jiaqi Guo,Xuan Wang,Li Yong,Lin Ren,Dejian Feng,Xiaoli Zou
Using high-performance liquid chromatography-mass spectrometry, fifteen bisphenols and halogenated phenols were simultaneously analyzed in tea for the first time in China. Response surface methodology was used to optimize sample preparation conditions based on QuEChERS. Finally, the limits of detection and the limits of quantification were 0.0200–0.173 μg/kg and 0.0892–0.770 μg/kg, respectively. The recoveries were 70 %–120 % for most compounds (except for some compounds at low spiked concentrations) with RSDs <20 %. Then 135 dried tea samples were analyzed. Bisphenol S, A and F were the predominant bisphenol contaminants with detection rates above 80 %, and the median level of bisphenol F (4.90 μg/kg) was even higher than that of bisphenol A (2.74 μg/kg). Bisphenol A ( p < 0.001) and bisphenol F ( p = 0.007) were significantly higher in black tea than in green tea. Hazard index was estimated and bisphenols in tea may pose potential risks to human health.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Foods
·
2024
·Vol. 13
·期 6
·865
·
IF 4.7
Yiwen Miao,Lilei Wang,Fei Bai,Shuting Zheng,Jingna Yan,Hao Wei,Qing Meng,Huarong Tong
This study aims to investigate the relationship between the grades of Tuo tea and the quality of compounds. A combination of artificial sensory evaluation, intelligent sensory technologies (electronic nose and electronic tongue), gas chromatography–mass spectrometry (GC-MS), high-performance liquid chromatography (HPLC), chemical–physical analysis, and multivariate statistical analysis were employed to examine the differences among three grades of Tuo tea (SG, 1G, and 2G). The results of artificial sensory evaluation, electronic tongue, and electronic nose revealed that the aroma and taste of different grades of Tuo tea varied greatly. A total of 112 volatile compounds and 44 non-volatile compounds were identified. In order to elucidate the key components that cause differences in the quality of Tuo tea, 2 partial least squares discriminant analysis (PLS-DA) models with excellent parameters (volatile, R2Y = 0.999 and Q2= 0.996; non-volatile, R2Y = 0.992 and Q2= 0.972) were established. A total of 80 key differential volatile compounds were identified with the double selection criterion of variable importance in projection (VIP) greater than 1 andp< 0.05. Among these, 43 compounds with OAV > 1 were further identified as the odor-active compounds in all three grades of Tuo. Moreover, 22 key non-volatile compounds that contribute to the quality differences have been screened out. This investigation implied that the volatile and non-volatile compounds of Tuo tea could serve as indicators of its quality. The results provided a new approach to distinguish the grades of Tuo tea.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD SCIENCE AND TECHNOLOGY-MYSORE
·
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.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Wensong Chen,Wangxin Liu,Zhibin Liu,Daoliang Wang,Xiaoye Lan,Sijia Zhan,Xiaoxiao Feng,Yuan Liu,Li Ni
Wuyi Rock Tea (WRT) undergoes complex chemical transformations during roasting that significantly influence its aroma. This study explores the mechanisms involved in the formation of key aroma compounds, specifically alkylpyrazines and furans. Using HS-SPME-GC-O-MS and aroma dilution analysis, we identified 15 odor-active compounds, including three alkylpyrazines (2,6-diethyl-pyrazine, 2-ethyl-3,5-dimethyl-pyrazine, and 2-methyl-3,5-diethyl-pyrazine) and two furans (furfural and 5-methyl-2-furancarboxaldehyde), with odor-active values exceeding 1. An “in-leaf” labeling approach utilizing isotopically labeled alanine ([ 15 N]-Ala) and glucose ([U 13 C 6 ]-Glc) was employed to explore the contributions of tea leaf matrix and soluble compounds. Results indicated that the incorporation of two nitrogen atoms from alanine was the predominant pathway for alkylpyrazine formation, while five or six carbon atoms from glucose were primarily responsible for furan formation. Additionally, the insoluble tea leaf matrix contributed 13 % to 32 % of alkylpyrazines and 12 % to 25 % of furans. These findings enhance our understanding of the Maillard reaction's role in WRT's flavor development.
✓ 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）