The MW profiles of proanthocyanidin polymers (condensed tannins) from 32 samples representing a wide range of plant tissues of many different species have been obtained by gel permeation chromatography of the peracetate derivatives. The tannins vary widely in MW, with Al. values for the peracetates in the range 1600-5500. The MW profiles vary greatly from those with narrow, rather smooth distri...

This study assessed the impact of fruit temperature on the phenolic metabolism of grape berries (Vitis vinifera L. cv. Merlot) grown under field conditions with controlled exposure to sunlight. Individual cluster temperatures were manipulated in situ. Diurnal temperature fluctuation was damped by daytime cooling and nighttime heating of clusters. Daytime-only and nighttime-only temperature cont...

This study evaluated the antioxidant activity as well as bioflavonoid content of the methanol and ethanol-water extracts of the fresh and dried leaves of Tetracarpidium conophorum. Antioxidant activity was determined by spectrophotometric methods using DPPH free radical, nitric oxide radical inhibition and ferric reducing antioxidant power assays. In addition, total phenolics, flavonoids and pr...

The transcriptional response of hybrid poplar (Populus trichocarpa x P. deltoides) to poplar leaf rust (Melampsora medusae) infection was studied using the Populus 15.5K cDNA microarray. Pronounced changes in the transcriptome were observed, with approximately 20% of genes on the array showing either induction or repression of transcription within the 9-day infection timecourse. A small number ...

Anthocyanins and proanthocyanidins are widespread in the plant kingdom involved important bioactivities, such as antioxidation. These flavonoids can reduce risk of cardiovascular diseases, cancer, high blood pressure, hyperlipidemia, diabetes; consequently, they widely studied for disease prevention treatment. In this review, we summarize recent advances our understanding chemical structures, f...