JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2024
·
IF 4
Yujie Ai,Qidi Wu,Haibo Yuan,Yingqin He,Yongwen Jiang,Suzhen Niu
Catechins and theaflavins , as the primary bioactive constituents of black tea, have a significant impact on its color, aroma, and flavor profile. We developed a rapid and precise method using HPLC to detect catechins and theaflavins in black tea. The method employed 0.1% formic acid-acetonitrile (phase A) and 1% formic acid-water (phase B) as mobile phases . Separation occurred on an Agilent SB-C18 column (4.6 mm × 250 mm, 5 µm), with 20 μL injection volume. Detection took place at 30 °C with a flow rate of 1 mL/min for 55 min.Quantitative determination utilized the external standard method, exhibiting high sensitivity (limit of detection: 0.19 to 5.14 μg/mL) and a strong linear correlation (R2 ≥ 0.9993) between concentration range and peak area. Precision, repeatability, and stability were excellent, with relative standard deviations (RSDs) below 5% (n = 5). The average recovery rate of standard addition ranged from 98.02% to 102.57%, with an RSD of less than 3.17% (n = 5). In summary, this straightforward, efficient, and precise approach is well-suited for both qualitative and quantitative analysis of catechins and theaflavins in tea. It overcomes the limitations of previous methods, providing a valuable tool for evaluating the quality and composition of black tea.
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高影响因子
MEASUREMENT
·
2025
·
IF 5.6
Jintao Liang,Zhenshun Wei,Qing Huang,Jianlu Liang,XiuChuan Zhao,Zhide Zhou,Guiyin Li
Tea polyphenols are a general term for the total phenolic compounds in tea. Tea polyphenols play a crucial role in the quality of tea. Rapid detection of tea polyphenols is essential for tea harvesting and breeding. In this paper, a rapid method for the detection of tea polyphenols is presented based on diazotization coupling (DC) reaction and flow batch analysis system (FBAS). The tea polyphenols detection based on DC reaction can avoid interference from non-phenolic substances and improve detection accuracy. Meanwhile, FBAS for sample injection can shorten the analysis time, reduce the reagent consumption and improve the sensitivity. Experimental results demonstrate that absorbance values exhibit linearity with gallic acid concentrations in the range of 5 to 60 μg/mL, with a linear equation of y = 0.0279x + 0.0613 (R 2 = 0.9993) and a limit of detection (LOD) of 0.215 μg/mL (S/N=3). The method was applied to the detection of tea polyphenols in tea samples, with relative standard deviations (RSD) ranging from 0.326% to 0.659%. The DC-FBAS method has a high potential application with the requirements of portable, cost-effective, and highly precise on-site tea polyphenols detection.
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Yihang Zhang,Jing Guo,Jianbin Sun,Fucheng Guan,Jing Tao,Xuecui Song,Zheng Li
Tea bags have been extensively used in the food industry and daily life as an efficient way to pack tea. However, the large pores of the commercial tea bags not only lead to the inner contents of tea bag susceptible to bacteria and moisture but also result in the faster water infusion which is undesired during tea brewing. In this study, the polylactic acid (PLA)-PLA/sodium alginate (SA)/bromelain (BL) bilayer fiber membrane imitating the asymmetric wetting structure of lotus leaf blades was fabricated to avoid the above disadvantages of commercial tea bag. The PLA/SA/BL skin-core nanofiber membrane which imitating the skin-core structure of lotus leaf stems was first prepared as the hydrophilic and support layer, then a hydrophobic PLA layer was deposited on top via electrospinning. The PLA-PLA/SA/BL bilayer fiber membrane had a breaking strength of 5.5 MPa and started to decompose at 260 °C. Using this bilayer membrane , tea bags were designed with a novel structure where the hydrophobic PLA layer was placed in the same direction. The novel structure endow the those tea bags a slow and directional water transfer property. Therefore, the PLA-PLA/SA/BL bilayer fiber membrane has great potential for applications as tea bags.
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PubMed
高影响因子
Analytical Methods
·
2017
·Vol. 9
·期 43
·6131-6138
·
IF 1.9
Xiangyu Wang,Huihui Wu,Rongying Luo,Donghai Xia,Zhengjin Jiang,Hai Han
D-amino acids are currently paid attention to as new physiologically active substances. Foodstuffs and beverages containing D-amino acids are a matter of interest. Until now, the profiles of D-amino acids have not been reported in natural and fermented teas except theanine. In this study, an off-line 2D-HPLC method combining a Gemini C18 column and a CHIRALPAK® IC-3 column or a self-prepared poly(MQD-co-HEMA-co-EDMA) monolithic capillary column was employed for the separation and detection of D-amino acids in tea samples with the co-existence of a large amount of L-amino acids. The free amino acid fractions in longjing, black, oolong, and pu-erh tea samples were separated and collected after pre-column derivatization using 9-fluorenylmethoxycarbonyl (FMOC) chloride in the reversed-phase mode, and then were concentrated and separated to D- and L-forms on a chiral column. Among them, the D-form of isoleucine (Ile) (1.0–1.6%), alanine (Ala) (0.1–0.8%), phenylalanine (Phe) (0.1–0.4%), valine (Val) (0.2–0.3%), serine (Ser) (0.1–0.2%), aspartic acid (Asp) (0.2%), and proline (Pro) (0.1%) were detected in longjing and oolong teas. Differences between natural tea and fermented tea in the profiles of D-amino acids as well as the total amino acids were also observed. The results provided useful information for the bio-function research of D-amino acids in tea.
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Journal of Functional Foods
·
2025
·
IF 4
Lanlan Yang,Nian Yang,Yuanquan Ran,Huan Zhao,Qiong Hu,Yi Hong,Minyi Tian
Herein, the chemical constituents of Pittosporum glabratum leaf essential oil (EO) were analyzed, and its anticancer efficacy was explored in vitro and in vivo . Its primary phytochemicals were α -caryophyllene, ( E )- β -farnesene, and germacrene D. It displayed significant cytotoxicity against cancerous A549 cells and lower cytotoxicity against noncancerous MRC-5 cells. It induced cell cycle arrest in the G1 phase by downregulating CDK2-cyclin E1/2 and CDK4-cyclin D3 complexes and upregulating p21, thereby inhibiting A549 cell proliferation. It triggered A549 cell apoptosis via the mitochondrial pathway, resulting in the ratio increase of Bax/Bcl-2, ΔΨm decrease, Cyt c release, caspase-9 and caspase-3 activation, and PARP cleavage. It blocked migration ability by decreasing MMP-2, MMP-9, and N-cadherin levels. Additionally, it effectively suppressed tumor growth by inducing apoptosis of transplanted tumor cells in nude mice. Hence, P. glabratum leaf EO has remarkable anticancer properties and has great potential as an anticancer drug in the pharmaceutical field.
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高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Aminu Shehu Abubakar,Bilal Ahmad,Nabi Ahmad,Liangliang Liu,Bin Liu,Yatong Qu,Jikang Chen,Ping Chen,Haohan Zhao,Jia Chen,Kunmei Chen,Gang Gao,Aiguo Zhu
Luobuma tea is made from the leaves of Apocynum hendersonii (Bt) and A. venetum (Ht) and has been used for a very long time in China and Japan as herbal tea. This study isolated water-soluble polysaccharides from the two species` teas. Physicochemical properties, structural properties, in vitro and in vivo antioxidant and immunomodulatory activities were determined for the first time. The results showed that the Bt and Ht polysaccharides with molecular weights of 31.21 and 49.11 kDa, respectively, composed of arabinose, galactose, rhamnose, glucose, xylose, fucose, and mannose. A dose-dependent nitric oxide production and interleukin-6 inhibitory effects were obtained. Also, they suppressed the expression of cyclooxygenase-2, tumor necrosis factor-α and interleukin-6 mRNA in LPS-induced RAW 264.7 macrophages. Likewise, Bt and Ht have significantly reduced edema in the paws of mice after carrageenan injection. These results suggested that the Luobuma teas polysaccharides can be explored as potential antioxidants and anti-inflammatory agents.
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高影响因子
Horticulturae
·
2025
·Vol. 11
·期 2
·120
·
IF 3
Zi-Wei Zhou,Qing-Yang Wu,Yang Wu,Ting-Ting Deng,Xiao-Hui Chen,Shu-Ting Xiao,Chen-Xin Zhang,Yun Sun,Shi-Zhong Zheng
Wuyi Rock tea (WRT), originating from the northern region of Fujian province, has a good reputation for its distinctive Yan flavor and floral–fruity aroma. The aroma quality, an essential element of the Yan flavor, undergoes various changes during the manufacturing process of WRT. To enhance the understanding of the formation patterns of WRT aroma and its influence on the flavor quality of WRT, we utilized both manufactured WRT (Rougui tea) and primary tea as materials. Utilizing a sensory evaluation, detection of volatile compounds, and multivariate statistical analysis, we identified and characterized the distinctive volatile components present in WRT. The sensory evaluation and radar chart analysis revealed that the primary tea exhibited a strong and lasting aroma, along with a mellow taste and a prominent Yan flavor. Through gas chromatography time-of-flight mass spectrometry (GC-TOF MS), a total of 251 volatile compounds were identified. The odor activity value (OAV) was calculated to identify key aroma-active compounds in the primary tea. The results indicated that a total of 14 compounds had an OAV greater than 1.0, including (2-nitroethyl) benzene, indole, and geranylacetone. These compounds exhibited floral and fruity aroma attributes. They primarily formed and accumulated during the latter stages of WRT. Using a partial least squares discrimination analysis (PLS-DA) combined with a variable importance in projection (VIP) score greater than 1.0 as a criterion, a total of 89 compounds were identified. Furthermore, out of the selected compounds, 15 types, including geraniol, 1-nonanol, and 1-butyl-2-ethyl-cyclopropene, were found to exclusively exist during the enzymatic manufacturing stages, particularly during the intermediate and later phases of the turn-over process (the last-three-times turn-over treatments), exhibiting predominantly floral and sweet fragrances. In contrast, during the non-enzymatic stages, only four compounds, such as pentanoic acid and phenylmethyl ester, were detected, exhibiting a fruity aroma profile. These volatile compounds significantly influenced the quality attributes of the final tea product, resulting in strong and lasting characteristics, particularly marked by a pronounced floral and fruity aroma. This study revealed how the aroma quality in WRT is developed and pinpointed possible volatile compounds that react to post-harvest treatments, thereby offering valuable insights relating to the intelligent production strategies of WRT.
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高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Xiangdong Qing,Xinran Wu,Taoxiang Wang,Xiaohua Zhang,Zhiyuan Hu,Xiaohong Zhou,Jie Luan,Rong An
In the work, a novel strategy was developed to characterize and classify Chinese dark tea based on alternating trilinear decomposition combined with uniform manifold approximation and projection (ATLD-UMAP). Firstly, nine active components as targeted analytes were selected to construct qualitative and quantitative models to investigate the performance of ATLD-UMAP analysis of 3D fluorescence data. Spiked sample sets demonstrated that satisfactory results were returned with their average recoveries ranging from (91.4 ± 9.7)% to (109.3 ± 1.5)%. Subsequently, ATLD-UMAP was employed to analyze the contents of analytes in 124 real dark tea samples, revealing the presence of eight active components other than tryptophan with their average contents ranging from 0.22 mg·g −1 to 57.69 mg·g −1 . Finally, ATLD-UMAP was applied to discriminate tea samples produced from different geographical origins and processing depths, and compared with the targeted-based feature component analysis (ATLD-FCA) and the nontargeted-based principal component analysis (ATLD-PCA). The research findings demonstrated that ATLD-UMAP achieved satisfactory classification results (100.0 % accuracy, sensitivity and specificity) in simultaneously identifying dark tea's geographical origin and processing depth. In contrast, ATLD-FCA and ATLD-PCA failed to distinguish them accurately with accuracies of only 68.5 % and 64.8 %, respectively. In a word, ATLD-UMAP provides a new method for rapid authenticity identification in the dark tea industry.
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高影响因子
NEW JOURNAL OF CHEMISTRY
·
2025
·
IF 2.5
Yuanbin Li,Siyuan Chen,shanshan Li,Zhenyuan Wang,Chengyu Wu,Jichuan Zhang,Junzi Dong,Jiaheng Zhang
Bioactive constituents in Camellia sinensis (white tea) provide dermatoprotective benefits, but conventional extraction methods are often inefficient and cumbersome. Research on green extraction techniques for white tea and their effects on skin-related bioactivities remains limited. This study therefore established Natural Deep Eutectic Solvents (NaDESs) as a sustainable extraction platform for white tea bioactives and evaluated the multifunctional skincare properties of the resulting extracts. An optimized L-proline/xylitol NaDES significantly enhanced polyphenol extraction efficiency over traditional solvents. the NaDES-derived extract exhibited superior antioxidant and anti-photoaging effects due to its higher polyphenol content, while also inhibiting advanced glycation end-products (AGEs) formation—demonstrating anti-glycation potential. In conclusion, NaDES represents an advanced plant extraction solvent, and the derived white tea extract shows promise as a multifunctional skincare ingredient (antioxidant, anti-photoaging, anti-glycation) for cosmetic and food applications.
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INDUSTRIAL CROPS AND PRODUCTS
·
2025
·
IF 6.2
Yanfei Wang,Muhammad Yasir,Noman Walayat,Isam A. Mohamed Ahmed,Wen Zhang,Jian Zheng,Zhucheng Su,Ran Wei
While withering and drying are key variables influencing white tea (WT) flavor, the combined effects of different withering methods and drying temperatures remain elusive. The current study investigated variations in sensory profiles, non-volatile and volatile compounds in WT under three withering methods and drying temperatures (55 °C, 80 °C, and 105 °C) combinations. Among groups, the tank withering groups yielded relatively better taste, including sweetness, freshness and sweet aftertaste, alongside lower bitterness. Increasing drying temperature elevated bitterness and baking aroma intensity while decreasing sweet aftertaste and sweetness. A prominent fresh floral aroma was observed under the medium drying temperature. In terms of non-volatile compounds, polyphenol levels increased with elevated drying temperature, while amino acid contents were mostly accumulated under medium drying temperature across all three withering methods. Additionally, non-targeted metabolic analysis revealed significant differences among combinations. Moreover, a total of 66 volatile compounds were identified across all groups, with phytol, methyl salicylate, benzaldehyde, benzeneacetaldehyde, and nonanal exhibiting higher odor activity values (OAV > 1), indicating their significant contribution to the aroma of WT. Furthermore, after optimization via optimal design analysis, the predicted optimal processing parameters for WT were tank withering combined with a drying temperature of 84 ℃. Overall, the findings underscore the crucial role of different combinations of withering methods and varying drying temperatures in shaping the flavor profile of WT, which provides a theoretical basis for WT processing.
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Food Chemistry-X
·
2025
·
IF 8.2
Xinyi Sun,Ceyu Wang,Xingyu Long,Shumei Han,Wei Xu,Taolin Chen,Jianjun Liu,Beibei Wen,Meifeng Li
Niangniang tea is typically processed using a two-stage bunch-drying process, which gives it distinct floral aroma characteristics. This study investigated the impact of the two-stage bunch-drying process on the formation of Niangniang tea's floral aroma and compared it with green tea and yellow tea. Sensory evaluation, metabolomics, aroma recombination and omission tests, and molecular docking results revealed that Niangniang tea's key aroma compounds were linalool, hotrienol, p -anisaldehyde, 5-nonanone, S -methyl thiohexanoate, 1-nonen-3-ol, and 2-isopropyl-3-methoxypyrazine. p -Anisaldehyde, linalool, and hotrienol were responsible for Niangniang tea's intense floral aroma, and p -anisaldehyde was the marker of the floral aroma of NNT. This study identified the key floral compounds in Niangniang tea and revealed how the two-stage bunch-drying process influenced aroma formation. These results provide a theoretical basis for optimizing the bunch-drying process parameters in future studies.
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高影响因子
Food Chemistry-X
·
2025
·
IF 8.2
Wu Yang,Wu Qingyang,Zhou Ziwei,Deng Tingting,Sun Yun
Innovative Jinmudan black tea shows pronounced sweet aroma and taste, but the mechanisms by which volatile compounds enhance sweetness remain unclear. This study combined flavoromics, molecular modeling, and sensory analysis to identify key aroma compounds responsible for the sweetening sensory effect. HS-SPME-GC–MS and multivariate analysis characterized 93 sweet-related volatiles, of which 30 were screened by Partial Least Squares-Discriminant Analysis (PLS-DA). Six representative compounds covering major sweet-aroma subtypes were selected for in silico analysis. Molecular docking and dynamics revealed stronger and more stable binding of these volatiles to the sweet receptor T1R3 than to T1R2. Aroma addition tests using a low-sweetness Jinmudan black tea confirmed that five compounds enhanced perceived sweetness, with ( Z )-3-hexen-1-ol benzoate and 2-methyl-2-phenylethyl propanoic acid showing the greatest effects. These findings clarify aroma-taste interactions in innovative black tea and provide a reference for sweetness modulation in tea-based foods.
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高影响因子
危险品化学品经营许可证（带存储）