Indole-3-acetaldoxime (IAOx) is an important intermediate in the biosynthesis of several plant secondary metabolites. It is a precursor of several cruciferous phytoalexins (e.g. brassinin and camalexin), as well as of indole glucosinolates (glucobrassicin) and the plant hormone indole-3-acetic acid. Previous work showed that the plant pathogen Sclerotinia sclerotiorum transformed IAOx to indolyl-3-acetonitrile using an indolyl-3-acetaldoxime dehydratase, IADSs. In this work, IAOx activity was screened in mycelia from different crucifer pathogenic fungi. Leptosphaeria maculans isolate Laird 2 metabolized IAOX and mycelial cell-free extracts showed the highest activity among the tested pathogens. Partially purified indolyl-3-acetaldoxime dehydratase showed Michaelis–Menten kinetics, had an apparent molecular mass of 40 kDa and maximum activity at pH 6.5 and 22-25 0C. Sodium dithionite was used in all enzyme assays, and enzymatic activity was enhanced under anaerobic conditions in the presence of dithionite. The enzyme was stabilized in the presence of detergents and glycerol; however, it was strongly inhibited by dithiothreitol and antiproteases. On the basis of its substrate specificity, the enzyme appears to be an indolyl-3-acetaldoxime dehydratase similar to IADSs. Partial purification, stabilization and substrate specificity studies of IAD from Laird 2 will be described and results compared with previous work.

The detailed macro- and micromorphological characters of the leaf, stem and root of Juglans nigra Linn. (Black Walnut) cultivated in Egypt have been studied in order to find out the diagnostic features which can help in the identuification of the plant in both entire and powdered forms.

The detailed macro- and micromorphological characters of the leaf, stem and root of Juglans nigra Linn. (Black Walnut) cultivated in Egypt have been studied in order to find out the diagnostic features which can help in the identuification of the plant in both entire and powdered forms.

The detailed macro- and micromorphological characters of the leaf, stem and root of Juglans nigra Linn. (Black Walnut) cultivated in Egypt have been studied in order to find out the diagnostic features which can help in the identuification of the plant in both entire and powdered forms.

The detailed macro- and micromorphological characters of the leaf, stem and root of Juglans nigra Linn. (Black Walnut) cultivated in Egypt have been studied in order to find out the diagnostic features which can help in the identuification of the plant in both entire and powdered forms.

From the methanolic extract of the leaves of Juglans nigra L. (Black Walnut) Family Juglandaceae (Walnut family), kaempferol-3-O-ß-glucoside quercetin-3-O-ß-glucoside and quercetin-3-O- ß-glucoside-6``-ethyl ester were isolated for the first time from the family Juglandaceae, in addition to stigmasterol-3-O-ß-glucoside. The structures were established on the basis of UV, MS and NMR (1H, 13C and DEPT) spectroscopic data. Moreover, the hypotensive and toxicological studies were done.

From the methanolic extract of the leaves of Juglans nigra L. (Black Walnut) Family Juglandaceae (Walnut family), kaempferol-3-O-ß-glucoside quercetin-3-O-ß-glucoside and quercetin-3-O- ß-glucoside-6``-ethyl ester were isolated for the first time from the family Juglandaceae, in addition to stigmasterol-3-O-ß-glucoside. The structures were established on the basis of UV, MS and NMR (1H, 13C and DEPT) spectroscopic data. Moreover, the hypotensive and toxicological studies were done.

From the methanolic extract of the leaves of Juglans nigra L. (Black Walnut) Family Juglandaceae (Walnut family), kaempferol-3-O-ß-glucoside quercetin-3-O-ß-glucoside and quercetin-3-O- ß-glucoside-6``-ethyl ester were isolated for the first time from the family Juglandaceae, in addition to stigmasterol-3-O-ß-glucoside. The structures were established on the basis of UV, MS and NMR (1H, 13C and DEPT) spectroscopic data. Moreover, the hypotensive and toxicological studies were done.

Destruxin B and sirodesmin PL are phytotoxins produced by the phytopathogenic fungi Alternaria brassicae (Berk.) Sacc. and Leptosphaeria maculans (asexual stage Phoma lingam), respectively. The molecular interaction of destruxin B and sirodesmin PL with cruciferous and cereal species was investigated using HPLC-ESI-MS(n). It was determined that crucifers transformed destruxin B to hydroxydestruxin B, but sirodesmin PL was not transformed. Overall, the results suggest that the five cruciferous species Arabidopsis thaliana, Thellungiella salsuginea, Erucastrum gallicum, Brassica rapa and Brassica napus are likely to produce a destruxin B detoxifying enzyme (destruxin B hydroxylase), similar to other cruciferous species reported previously. In addition, HPLC analyses and quantification of the phytoalexins elicited in each cruciferous species by these phytotoxins indicates that sirodesmin PL elicits a larger number of phytoalexins than destruxin B. Interestingly, transformation of destruxin B appears to occur also in the cereals Avena sativa and Triticum aestivum; however, the various destruxin metabolites detected in these cereals suggest that these reactions are non-specific enzymatic transformations, contrary to those observed in crucifers, where only a main transformation pathway is detectable. None of the toxins appear to elicit production of metabolites in either A. sativa or T. aestivum.