Food extract supplements, with high functional activity and low side effects, play a recognized role in the adjunctive therapy of human colorectal cancer. The present study reported a new functional beverage, which is a type of Chinese Hakka stir-fried green tea (HSGT) aged for several years. The extracts of the lyophilized powder of five HSGT samples with different aging periods were analyzed with high-performance liquid chromatography. The major components of the extract were found to include polyphenols, catechins, amino acids, catechins, gallic acid and caffeine. The tea extracts were also investigated for their therapeutic activity against human colorectal cancer cells, HT-29, an epithelial cell isolated from the primary tumor. The effect of different aging time of the tea on the anticancer potency was compared. Our results showed that, at the cellular level, all the extracts of the aged teas significantly inhibited the proliferation of HT-29 in a concentration-dependent manner. In particular, two samples prepared in 2015 (15Y, aged for 6 years) and 2019 (19Y, aged for 2 years) exhibited the highest inhibition rate for 48 h treatment (cell viability was 50% at 0.2 mg/mL). Further, all the aged tea extracts examined were able to enhance the apoptosis of HT-29 cells (apoptosis rate > 25%) and block the transition of G1/S phase (cell-cycle distribution (CSD) from 30%) population to G2/M phase (CSD from nearly 30% to nearly 10%) at 0.2 mg/mL for 24 h or 48 h. Western blotting results also showed that the tea extracts inhibited cyclin-dependent kinases 2/4 (CDK2, CDK4) and CylinB1 protein expression, as well as increased poly ADP-ribose polymerase (PRAP) expression and Bcl2-associated X (Bax)/B-cell lymphoma-2 (Bcl2) ratio. In addition, an upstream signal of one of the above proteins, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signalling, was found to be involved in the regulation, as evidenced by the inhibition of phosphorylated PI3K and AKT by the extracts of the aged tea. Therefore, our study reveals that traditional Chinese aged tea (HSGT) may inhibit colon cancer cell proliferation, cell-cycle progression and promoted apoptosis of colon cancer cells by inactivating PI3K/AKT signalling.

Type 2 diabetes mellitus is a disease caused by hyperglycemia, an imbalance in the intestinal flora and disruption of the endocrine system. At present, it is primarily controlled through drug treatment and an improved diet. Mulberry leaf and fu brick tea were considered to have excellent hypoglycemic effects. This study used mulberry leaves and fu brick tea as raw materials to develop a dietary regulator that can assist in the prevention and alleviation of diabetes. The experiment used the Goto-Kakizaki (GK) rat model to investigate the hypoglycemic effect of mulberry leaf fu tea (MFT) and its influence on the intestinal flora of diabetic rats through methods including ELISA, tissue section observation and 16S RNA microbial sequencing. The results showed that, compared with the GK group, the intervention of mulberry leaf fu tea significantly reduced the activities of α-glucosidase (p < 0.05) and α-amylase (p < 0.05) in the duodenum of GK diabetic rats. The height of the duodenal villi was significantly reduced (p < 0.001), leading to decreased intestinal sugar absorption. At the same time, MFT alleviates the imbalance of intestinal flora caused by high blood sugar, promotes the growth of beneficial bacteria (Lactobacillus, Bifidobacterium, etc.), and inhibits the reproduction of harmful bacteria (Blautia, Klebsiella, Helicobacter, Alistipes, etc.). MFT helps reduce the secretion of toxic substances (lipopolysaccharide, p < 0.001), decreases oxidative stress and inflammation, mitigates organ damage, and improves symptoms of diabetes. Finally, the random blood glucose value of GK rats dropped from 22.79 mmol/L to 14.06 mmol/L. In summary, mulberry leaf fu tea can lower sugar absorption in diabetic rats, reduce the body’s oxidative stress and inflammatory response, regulate intestinal flora, and reduce blood sugar levels in GK rats. It is hinted that mulberry leaf fu tea could be used as a functional drink to help prevent the occurrence of diabetes.

This study used a targeted metabolomics approach to examine changes in metabolites within green tea infusions fermented by G. lucidum (TFG) and evaluate the in vitro antioxidant and lipid-lowering properties of TFG. Fermentation decreased tea polyphenols, flavonoids, caffeine, soluble sugars, theaflavins, and catechins, while increasing free amino acids and theabrownins. The microbial bioconversion process led to the generation of decorated flavonoids, phenolic acids, terpenoids, alkaloids, nucleotides, and amino acids. This process shifted the tea’s taste from bitter and astringent to mellow, primarily due to the transformation of flavonoid glycosides, caffeine, catechins, 5′-guanosine monophosphate, 5′-uridine monophosphate, and theabrownins. Volatile metabolites added woody, floral, sweet, and fruity aromas. Reduced gallic acid and catechins lowered antioxidant activity, whereas increased theabrownins enhanced lipid-lowering activity and imparted a reddish-brown color. These findings indicate that fermentation significantly affects the flavor, aroma, and lipid-lowering ability of green tea infusion.

Human colorectal cancer is notorious for its high morbidity and mortality; however, the lack of effective and low-toxic drugs has currently been a bottleneck for the treatment of the disease. The present study reported a new functional food of Hakka stir-fried green tea (HSGT) aged with different years, including those stored starting from 2003 (03Y), 2007 (07Y), 2011 (11Y), 2015 (15Y) and 2019 (19Y) respectively, for their effective therapeutic activity against colorectal cancer. The major active ingredients including polyphenols, catechins, amino acids, catechins, gallic acid and caffeine found in the lyophilized powder of these aged HSGT were analyzed with high performance liquid chromatography. Our results showed that, at the cellular level, all these aged HSGT inhibited significantly the proliferation of colon cancer cells (HT-29) in a concentration-dependent manner. In particular, the batch of 15Y and 19Y exhibited the highest inhibition rate for 48 hours treatment. Further, all these aged HSGT examined were able to enhance the apoptosis of HT-29 cells and block the transition of G1/S phase population to G2/M phase. Western blotting results also showed that the aged HSGT inhibited CDK2, CDK4 and CylinB1 protein expression, as well as increased PRAP expression and Bax/Bcl2 ratio in HT-29 cells. In addition, an upstream signal, PI3K/AKT signaling, was found involving in this regulation, as evidenced by the inhibition of phosphorylated PI3K and AKT by the aged HSGT. Therefore, our study reveals that the aged HSGT may inhibit colon cancer cell proliferation, cell cycle progression and promoted apoptosis of colon cancer cells by inactivating PI3K/AKT signalling. The therapeutic effects of the HSGT aged with different years were also investigated.

This study integrated sensory evaluation, volatile profiling (HS-SPME/GC × GC-Q-TOF-MS) and non-volatile profiling (UHPLC-Orbitrap-MS), and multivariate analysis to characterise 13 Sun-Dried Green Tea samples from Xishuangbanna, Yunnan, China. A total of 230 volatile and 226 non-volatile compounds were identified, and metabolite profiles were more similar among geographically adjacent production regions. Based on the intensity of the floral–fruity aroma, the samples were classified into three groups: strong, relatively strong, and pure, with a weak floral–fruity aroma. The strong floral–fruity group, comprising samples from Mengla and vicinity, contained high levels of Nonanal, Decanal, 2-pentylfuran, benzaldehyde, cis-linalool oxide, safranal, and 6-methyl-5-hepten-2-one. The moderately rich floral–fruity group, consisting of high-altitude Menghai samples, exhibited significantly higher levels of limonene, linalool, p-cymene, β-myrcene, γ-terpinene, terpinolene, and α-terpinene, compounds with both floral and woody attributes. Menghai and vicinity samples were characterised by higher levels of proanthocyanidins, hydrolyzable tannins, and amino acids, which account for their pronounced astringency and sweet aftertaste. In contrast, samples from Mengla and the vicinity exhibited higher levels of Myricetin 3-O-glucoside, Isoschaftoside, and Epigallocatechin 3-O-(3-O-methylgallate). Key differential compounds revealed that multiple environmental factors drive distinct metabolite profiles, which may underlie the regional quality difference of Sun-Dried Green Tea. These findings provide a theoretical reference for production improvement and market guidance.