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The change in activity of cinnamic acid 4-hydroxylase (CA4H) in potato parenchyma tissue exposed to various conditions has been examined. Maximum induction of CA4H activity was obtained at 18 hr of incubation. Though CA4H induction can occur in dark, over 100% increase in enzyme activity was
Exogenous supplies of phenylalanne, cinnamic acid and p-coumaric acid can inhibit the appearance of phenylalanine ammonia-lyase (PAL, E.C. 4.3.1.5) activity in potato tuber discs, and exogenous supplies of cinnamic acid and p-coumaric acid can inhibit the appearance of cinnamic acid 4-hydroxylase
Cinnamic acid-4-hydroxylase activation factor has been found to be located in the supernatant fraction of wounded potato tissue homogenate in phosphate buffer. The factor has been purified to homogeneity as judged by SDS polyacrylamide gel electrophoresis, by heat treatment on boiling water-bath for
The cytoplasmic localisation of cinnamic acid 4-hydroxylase (CA4H) has been shown by isolation and subcellular fractionation of the enzyme in Hepes buffer. The enzyme was purified by ammonium sulphate fractionation followed by AcA-34 molecular sieve chromatography. The enzyme existed as a high
Phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) and cinnamic acid 4-hydroxylase (CA4H, EC 1.14.13.11) undergo concomitant increases in activity after a 2 h lag following disc preparation and illumination. The increases in PAL and CA4H activity can be inhibited by actinomycin-D, cordycepin and
The interaction of trans-cinnamic acid with the cytochrome P-450 of microsomes derived from washed potato slices has been studied. The washing process increased the specific content of microsomal electron transport components and hence provided a useful material in which to study the interaction.
Development of novel approaches for the control of fungal phytopathogens is desirable. In this study we hypothesized that the combination of commercial fungicides with certain enhancing agents could result in synergistic levels of control. Prior research has indicated that trans-cinnamic-acid (TCA),
The outer potato periderm layer consists of dead suberized cells. Suberin, a protective biopolymer, is made of a polyaliphatic portion covalently linked to polyaromatic moieties. Evidence accumulates that Streptomyces scabies, the main causal agent of potato common scab, can degrade the
In this work, maltodextrin-grafted-cinnamic acid (MD-g-CA) was synthesised and used as wall material to improve the stability of purple sweet potato anthocyanins (PSPa) via microencapsualtion. MD-g-CA was prepared through esterification in a two-step convenient synthesis procedure and characterised
Three new pentasaccharide resin glycosides, batatosides III-V (1-3), were isolated from the roots of Sweet potato (Ipomoea batatas). Saponification of the crude resin glycoside mixture yielded substituents and simonic acid B. The structures of the isolated compounds (1-3) were established through
Previously, we isolated t-cinnamoyl-D-glucose as a possible intermediate in chlorogenic acid biosynthesis from sweet potato root. The enzyme which catalyzes the formation of t-cinnamoyl-D-glucose has been purified 539-fold from sweet potato root (Ipomoea batatas Lam.) and characterized. It required
Ipomeamarone 15-hydroxylase activity was found in a microsomal fraction from cut-injured and Ceratocystis fimbriata-infected sweet potato (Ipomoea batatas Lam. cv. Norin No. 1) root tissues and its optimum pH was 8.0. The enzyme reaction required O(2) and NADPH. The K(m) values calculated for
Marked polyphenol production takes place in root tissue of sweet potato, Ipomoea batatas Lam. cv. Norin 1, in response to slicing. A possible intermediate, tentatively termed compound V, of chlorogenic acid biosynthesis was isolated from the root tissue administrated with t-cinnamic acid-2-(14)C.
Investigation of polyphenol production in cut-injured sweet potato (Ipomoea batatas Lam. cv. Kokei 14) roots by histochemical and quantitative methods showed that polyphenols were produced in striking amounts in the proximal side of the tissue pieces (2 cm thick), but only in small amounts in cells
Batatins I (1) and II (2), two ester-type dimers of acylated pentasaccharides, have been isolated by recycling HPLC from the hexane-soluble extract of sweet potato (Ipomoea batatas var. batatas). The structures were elucidated by a combination of high-resolution NMR spectroscopy and mass