Ammonia-lyase activity for L-phenylalanine, m-hydroxyphenylalanine and L-tyrosine was demonstrated in cell-free extracts ofSporobolomyces roseus. Cultures of this organism converted DL-[ring-14C]phenylalanine and L-[U-14C]tyrosine into the corresponding cinnamic acid. Tracer studies showed that these compounds were further metabolized to [14C]protocatechuic acid. Benzoic acid andp-hydroxybenzoi...

Potato tuber disks, when treated with laminarin, a beta-1,3-glucooligosaccharide from Laminaria digitata, accumulate a hydroxycinnamoyl amide compound, N-p-coumaroyloctopamine (p-CO). The biosynthesis of p-CO was investigated by feeding experiments, in order to show that the precursors of N-p-coumaroyl and octopamine moieties of p-CO are L-phenylalanine and L-tyrosine, respectively. The treatme...

The effect of gamma irradiation on lignin biosynthesis during wound healing in potato tubers was studied by [U-C] phenylalanine incorporation into lignin and monitoring the activities of key enzymes involved in the lignification process. There was a 40% reduction in lignin biosynthesis during wound healing in response to gamma irradiation. The level of the first enzyme involved in lignin biosyn...

The pool sizes of free l-phenylalanine and l-tyrosine, the precursors of rosmarinic acid in Anchusa officinalis L. cell suspension cultures, fluctuated during the culture cycle. The major increase in pool sizes was preceded by a peak of prephenate aminotransferase activity, while the subsequent decrease coincided with the presence of high activities of phenylalanine ammonia-lyase and tyrosine a...

A randomized complete block design experiment was designed to characterize the relationship between production of total flavonoids and phenolics, anthocyanin, photosynthesis, maximum efficiency of photosystem II (Fv/Fm), electron transfer rate (Fm/Fo), phenyl alanine lyase activity (PAL) and antioxidant (DPPH) in Labisia pumila var. alata, under four levels of irradiance (225, 500, 625 and 900 ...

Changes in the activity of antioxidant enzymes, proline, and total soluble carbohydrates (TSC) were evaluated in tomato (Solanum lycopercicum cv. Superchief) plants in response to salicylic acid (SA) and jasmonic acid (JA) and inoculation with CMV (Cucumber mosaic virus) on days 0, 1, 2, 4, 6, 8, and 15 after virus inoculation (dpi). Results showed that proline content increased in all treatmen...

Arbuscular mycorrhizal fungi (AMF) species and/or phosphorus addition in the soil can affect secondary metabolism production and growth plants. This study evaluated these effects on Piper divaricatum culture, which presents an essential oil rich phenylpropanoids. Growth parameters, leaf volatile composition, total phenolic content, enzymatic activity of lipoxygenase (LOX) phenylalanine ammonia-...

increased salinity stress because of rising temperature as a result of global warming. High salinity enhances plants photorespiration and affects its physiology, but Salicornia europaea L. in Urmia Lake has adapted to grow, propagate and occupy increasingly exposed saline habitats. Plant and soil samples were collected in triplicate plots from different sites of retreated beds of Urmia Lake in ...

Aspartate ammonia-lyase (AAL) catalyzes the reversible conversion reactions of aspartate to fumaric acid and ammonia. In this work, Lactobacillus paracasei LpAAL gene was heterologously expressed in Escherichia coli. As well as a recombinant His-tagged protein, maltose-binding protein (MBP) fused used enhance its solubility expression level. Both proteins showed broad substrate specificity, cat...