Tea () cultivated in three agro-ecological regions of Bangladesh: Unveiling the variability of methylxanthine, bioactive phenolic compound, and antioxidant activity.

Tea () is a widely consumed beverage known for its numerous health benefits, largely attributed to its rich content of quality determining secondary metabolites such as methylxanthine compounds and bioactive phenolic compounds. The goal of this study was to find out variations of the levels of methylxanthines, bioactive phenolic compounds, and antioxidant activity in methanolic and hot water extracts of 129 tea samples grown in three different ecological regions of Bangladesh named Panchagar, Sylhet, and Chattogram. Methylxanthine and bioactive phenolic compounds were determined by using HPLC-DAD, and the antioxidant profile was analysed by UV-vis spectrophotometric methods for methanol and hot water extracts of tea leaves.

Relative evaluation of in-vitro antioxidant potential and phenolic constituents by HPLC-DAD of vegetables extracted in different solvents.

Cabbage, cauliflower and broccoli are well-known vegetables from the family having functional effects on human health. This study was carried out to identify different antioxidant properties and to quantify phenolic compounds by HPLC-DAD in different extracts (methanol, ethanol and water: acetic acid: acetone) of these vegetables. The results showed that, the methanolic dry extract of cabbage possessed the highest antioxidant activity (549 ± 7.

Determination of dietary exposure and extraction efficiency of nitrosamine from cooked meat.

Meat products are claimed to be a source of carcinogenic nitrosamines (NAs) exposure in food. In this study, dietary exposure of six nitrosamines: N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosopyrrolidine (NPYR), N-nitrosopiperidine (NPIP), N-nitrosodipropylamine (NDPA), N-nitrosodibutylamine (NDBA) were estimated by Gas chromatography method. Four types of processed beef products were collected from different restaurants of Dhaka city, Bangladesh and analyzed by Gas chromatography-Mass spectrometry (GC-MS) after extracting under different methods.