Search

In present study, the quality of commercially brands of green and black tea available in Pakistan was analyzed on the basis of phenolic contents. Total phenolic content was analyzed through spectrophotometric measurement using the Ferrous Tartrate method. Individual catechins along with gallic acid and caffeine were determined using HPLC-UV. TPC of green tea was found to be higher than black tea. Among green tea brands, Lipton Clear Green showed higher TPC than Tapal Gulbahar. Both green and black tea polyphenols showed higher solubility in the aqueous acetone (50%, v/v) compared to water. (-)-EGCG was detected as the most abundant catechins in all green and black tea samples. Theaflavin content of Lipton Yellow Label and Vital was significantly higher than Tapal Family Mixture and Tetley. Based on catechins and theaflavins content, Lipton Clear Green, Lipton Yellow Label, and Vital Tea were considered to be of higher quality than other brands. [ABSTRACT FROM AUTHOR]

In present study, the quality of commercially brands of green and black tea available in Pakistan was analyzed on the basis of phenolic contents. Total phenolic content was analyzed through spectrophotometric measurement using the Ferrous Tartrate method. Individual catechins along with gallic acid and caffeine were determined using HPLC-UV. TPC of green tea was found to be higher than black tea. Among green tea brands, Lipton Clear Green showed higher TPC than Tapal Gulbahar. Both green and black tea polyphenols showed higher solubility in the aqueous acetone (50%, v/v) compared to water. (-)-EGCG was detected as the most abundant catechins in all green and black tea samples. Theaflavin content of Lipton Yellow Label and Vital was significantly higher than Tapal Family Mixture and Tetley. Based on catechins and theaflavins content, Lipton Clear Green, Lipton Yellow Label, and Vital Tea were considered to be of higher quality than other brands. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate the impact of untreated urban and industrial effluents on water quality of river Ravi. Water samples were collected from 11 polluted and relatively unpolluted sites at river Ravi during low flow season and analyzed for heavy metals content and physico-chemical parameters. Dissolved oxygen fell below the recommended limit for propagation of fish and other aquatic life as the river flows through Lahore up to Balloki Headworks. Manganese and lead contents were higher than permissible limits for aquatic ecosystems at several polluted sites of the river. Highest concentration of nickel, zinc, manganese, cadmium and lead detected in river water was 20.0 μg/L, 70.0 μg/L, 190.0 μg/L, 2.0 μg/L and 72.0 μg/L respectively. Findings revealed that river water at downstream sites of wastewater carrying drains was not suitable to support fish and other aquatic life due to its very low dissolved oxygen level. [ABSTRACT FROM AUTHOR]