fermentation is an important process for black tea production. during this process, by exposure of substrate to enzymes and the underlying oxidation reactions, quality determining factors of tea is produced. it is known that the exogenous application of cell-wall degrading enzymes leads to the increased production of these compounds through enhancement of enzyme-substrate interactions. pectinas...

The flavanone naringenin, an intermediate in flavonoid biosynthesis, was tested for its effect on root growth, phenylalanine ammonia-lyase (PAL) and peroxidase (POD) activities, as well as phenolic compounds and lignin contents in soybean (Glycine max L. Merrill) seedlings. Three-day-old seedlings were cultivated in half-strength Hoagland nutrient solution (pH 6.0), with or without 0.1 to 0.4 m...

A split plot 3 by 4 experiment was designed to examine the impact of 15-week variable levels of nitrogen fertilization (0, 90, 180 and 270 kg N/ha) on the characteristics of total flavonoids (TF), total phenolics (TP), total non structurable carbohydrate (TNC), net assimilation rate, leaf chlorophyll content, carbon to nitrogen ratio (C/N), phenyl alanine lyase activity (PAL) and protein conten...

Flavonoids are phytochemicals present in medicinal plants and contribute to human health. Coreopsis tinctoria , a species rich flavonoids, has long been used traditional medicine as food resource. N (nitrogen) fertilization can reduce flavonoid accumulation C. . However, there is limited knowledge regarding regulatory mechanisms. The aim of this study was determine the effect availability on bi...

A heterologous probe encoding phenylalanine ammonia-lyase (PAL) was used to identify PAL clones in cDNA libraries made with RNA from young leaf tissue of two Populus deltoides x P. trichocarpa F1 hybrid clones. Sequence analysis of a 2.4-kb cDNA confirmed its identity as a full-length PAl clone. The predicted amino acid sequence is conserved in comparison with that of PAL genes from several oth...

Ozone (O3), a major photochemical oxidant, induces leaf injury concomitant with salicylic acid (SA) synthesis. In pathogen-infected leaves, SA is synthesized via two pathways, involving phenylalanine or isochorismate. SA biosynthesis under O3 fumigation is not well understood. When we applied 14C-labeled benzoic acid (a precursor of SA in the pathway via phenylalanine) to O3-exposed tobacco lea...

Grafted and non-grafted tomato plants were grown at 25 and 35 ◦C for 30 days. In tomato leaves we analysed total phenols, o-diphenols, enzymatic activities (PAL, PPO and GPX) and dry weight. Our results indicate that heat stress in both grafted and non-grafted tomato plants occurred at 35 ◦C and resulted in (1) increased PAL activity, (2) increased total phenols and o-diphenols, (3) decreased P...

The paper describes the experience and presents the results of a retargeting exercise aimed at replacing the PAL-implemented control circuitry of a high-performance multiprocessor with FPGA devices. While straightforward retargeting is easy to perform, it does not give good results with respect to speed requirements. In order to attain the desired speed performance, it is necessary to redesign ...

Two strains of callus have been isolated from bean hypocotyl and grown on a defined maintenance medium supplemented with 2 mg/l. 2:4-dichlorophenoxyacetic acid (2:4D) and 2% sucrose. Root initiation was observed in one strain and formation of nodules containing xylem and phloem in both strains after transfer to an induction medium supplemented with 1 mg/l. naphthyleneacetic acid, 0-2 mg/l. kine...

Previously, we found that phenolic content and antioxidant capacity (AOX) in carrots increased with wounding intensity. It was also reported that UV radiation may trigger the phenylpropanoid metabolism in plant tissues. Here, we determined the combined effect of wounding intensity and UV radiation on phenolic compounds, AOX, and the phenylalanine ammonia-lyase (PAL) activity of carrots. Accordi...