Esterification of black bean anthocyanins with unsaturated oleic acid, and application characteristics of the product.

Esterification of anthocyanins with saturated fatty acids have been widely investigated, while that with unsaturated fatty acids is little understood. In this study, crude extract (purity âˆ¼ 35 %) of cyanidin-3-O-glucoside (C3G) from black bean seed coat was utilized as reaction substrate, and enzymatically acylated with unsaturated fatty acid (oleic acid). Optimization of various reaction parameters finally resulted in the highest acylation rate of 54.3 %. HPLC-MS/MS and NMR analyses elucidated the structure of cyanidin-3-O-glucoside-oleic acid ester (C3G-OA) to be cyanidin-3-O-(6″-octadecene)-glucoside. Introduction of oleic acid into C3G improved the lipophilicity, antioxidant ability, and antibacterial activity. Further, the color and substance stability analyses showed that the susceptibility of C3G and C3G-OA to different thermal, peroxidative, and illuminant treatments were highly pH dependent, which suggested individual application guidelines. Moreover, C3G-OA showed lower toxicity to normal cell (QSG-7701) and better inhibitory effect on the proliferation of HepG2 cells than C3G, which indicated its potential anti-tumor bioactivity.

Theabrownin from Dark Tea Ameliorates Insulin Resistance via Attenuating Oxidative Stress and Modulating IRS-1/PI3K/Akt Pathway in HepG2 Cells.

Dark tea has great potential in regulating glycolipid metabolism, and theabrownin (TB) is considered to be the characteristic and bioactive constituent of dark tea. This study evaluated the ability of TB1 (fermented for 7 days) and TB2 (fermented for 14 days) isolated from dark tea to reverse insulin resistance (IR) in HepG2 cells. The results indicated that TB significantly ameliorated oxidative stress by improving mitochondrial function. In addition, TB improved glycogen synthesis and glucose consumption, and inhibited gluconeogenesis and fatty acid synthesis, by regulating GSK3ß (Glycogen synthase kinase 3ß), G6Pase (Glucose-6-phosphatase), GCK (Glucokinase), PEPCK1 (Phosphoenolpyruvate carboxy kinase 1), SREBP-1C (sterol regulatory element-binding protein 1C), FASN (fatty acid synthase), and ACC (Acetyl-CoA carboxylase). Additionally, the results of Western blot and real-time PCR experiments demonstrated that TB modulated glucolipid metabolism through the IRS-1 (Insulin receptor substrate 1)/PI3K (phosphatidylinositol-3 kinase)/Akt (protein kinase B) signaling pathway. Treatment with the PI3K inhibitor demonstrated a favorable correlation between PI3K activation and TB action on glycolipid metabolism. Notably, we observed that TB2 had a greater effect on improving insulin resistance compared with TB1, which, due to its prolonged fermentation time, increased the degree of oxidative polymerization of TB.

Maternal tobacco exposure and health-related quality of life during pregnancy: a national-based study of pregnant women in China.

BACKGROUND: With the increase of the number of smokers, tobacco exposure among pregnant women is becoming more and more common. Pregnant women exposed to first-hand smoke and second-hand smoke are susceptible to physiological and psychological health issues has been proved in previous studies. Nevertheless, there are no enough studies focus on the impact of third-hand smoke during pregnancy. This study aimed to assess and compare health-related quality of life for pregnant women with exposure to first-hand smoke, second-hand smoke, third-hand smoke and non-exposure to tobacco in mainland China. METHODS: National-based cross-sectional study is based on a questionnaire survey which collects information including demographics, smoking behaviors and self-evaluation. All questionnaires were delivered and collected from August to September 2019. EuroQol group's visual analog scale and EuroQoL Five-dimension Questionnaire were used to collect data in mainland China. RESULTS: Totally, 15,682 pregnant women were included in this study, among which non-exposure to smoke were 7564 (48.2%), exposed to first-hand smoke, second-hand smoke and third-hand smoke were 89 (0.6%), 2349 (15.0%), and 5680 (36.2%) respectively. Pregnant women without tobacco exposure had the highest EuroQol group's visual analog scale score (mean value = 85.4[SD = 14.0]), while those with first-hand smoke had the lowest score (mean value = 77.4[SD = 22.2]). Among all five dimensions of EuroQoL Five-dimension Questionnaire, there were significant differences of EQ-index among groups with different tobacco exposure in usual activity and anxiety or depression dimensions (p < 0.001). CONCLUSIONS: Third-hand smoke exposure had close relationship with low health-related quality of life in pregnant women. Moreover, second-hand smoke exposure significantly led more problems on mental dimension of pregnant women.

One-step duplex RT-droplet digital PCR assay for the detection of norovirus GI and GII in lettuce and strawberry.

The study was designed to develop a sensitive one-step duplex reverse transcription droplet digital polymerase chain reaction (RT-ddPCR) to detect norovirus genogroup I and II (NoV GI and GII) in lettuce and strawberry. The specificity, sensitivity, repeatability and robustness of the assay was compared with RT-qPCR. The lowest concentration detected by RT-ddPCR for NoV GI and NoV GII were 4.68 and 8.47 copies/µL respectively, much lower than that of RT-qPCR with a number of 46.8 and 84.7 copies/µL, respectively. Lettuce and strawberry samples were artificially contaminated with NoV GI and GII suspensions, with inoculum size of 3.00 × 106 to 1.70 × 108 copies and 4.80 × 105 to 2.50 × 107 copies, respectively. Strawberry spiked with low inoculum size revealed positive results by RT-ddPCR, while recorded negative by RT-qPCR. Meanwhile, RT-ddPCR also showed a higher average recovery rate for NoV in lettuce and strawberry than RT-qPCR.The limit of detection (LoDs) of RT-ddPCR for NoVs in lettuce was 2.32 × 104 copies/25g (NoV GI) and 2.36 × 104 ciopies/25g (NoV GII), and that in strawberry was 2.56 × 104 copies/25g (NoV GI) and 2.64 × 104 ciopies/25g (NoV GII), which were 10 folds lower than that of RT-qPCR. The developed duplex RT-ddPCR assay exhibited stability and increased capacity to resist inhibitors in food samples with low concentration of NoV, making it a reliable method to avoid false negative result as opposed to RT-qPCR. In conclusion, one-step RT-ddPCR method developed in this study is pertinent in detecting foodborne virus such as NoV.

The Influence of Average Temperature and Relative Humidity on New Cases of COVID-19: Time-Series Analysis.

BACKGROUND: The influence of meteorological factors on the transmission and spread of COVID-19 is of interest and has not been investigated. OBJECTIVE: This study aimed to investigate the associations between meteorological factors and the daily number of new cases of COVID-19 in 9 Asian cities. METHODS: Pearson correlation and generalized additive modeling (GAM) were performed to assess the relationships between daily new COVID-19 cases and meteorological factors (daily average temperature and relative humidity) with the most updated data currently available. RESULTS: The Pearson correlation showed that daily new confirmed cases of COVID-19 were more correlated with the average temperature than with relative humidity. Daily new confirmed cases were negatively correlated with the average temperature in Beijing (r=-0.565, P<.001), Shanghai (r=-0.47, P<.001), and Guangzhou (r=-0.53, P<.001). In Japan, however, a positive correlation was observed (r=0.416, P<.001). In most of the cities (Shanghai, Guangzhou, Hong Kong, Seoul, Tokyo, and Kuala Lumpur), GAM analysis showed the number of daily new confirmed cases to be positively associated with both average temperature and relative humidity, especially using lagged 3D modeling where the positive influence of temperature on daily new confirmed cases was discerned in 5 cities (exceptions: Beijing, Wuhan, Korea, and Malaysia). Moreover, the sensitivity analysis showed, by incorporating the city grade and public health measures into the model, that higher temperatures can increase daily new case numbers (beta=0.073, Z=11.594, P<.001) in the lagged 3-day model. CONCLUSIONS: The findings suggest that increased temperature yield increases in daily new cases of COVID-19. Hence, large-scale public health measures and expanded regional research are still required until a vaccine becomes widely available and herd immunity is established.