Acyclic diterpene alcohols isolated from four algae of Bryopsidophyceae and their toxicity

Three new acylic diterpenoids belonging to the class of phytol series have been isolated. They were obtained from the ethyl acetate soluble fractions of four siphonaceous green seaweeds, Bryopsis pennata Lamour., Caulerpa taxifolia (Vahl) C. Ag., Codium decorticatum (Woodw.) Howe and Valoniopsis pachynema (Mart.) Børg., collected from Karachi coast of Pakistan. Structures of these compounds were elucidated with the help of spectroscopic methods and confirmed by comparison with the known compounds. Even the known compounds are being reported for the first time from a green algal source. All the compounds were found to display a strong toxicity at all the three concentrations tested in the brine shrimp bioassay

Sterol composition of marine algae from Karachi coast of Arabian Sea

During the course of chemical investigation of marine algae collected from Karachi coast of Arabian Sea, five sterols named as sarangosterol(1), 23-methyl cholesta-5, 25-dien-3ß-ol(2) from Endarachne binghamiae (brown alga), sargasterol(3) from Dictyota indica (brown alga), cholesterol(4) from Laurencia obtusa (red alga) and clerosterol(5) from Codium iyengarii (green alga) have been isolated. Their structures were elucidated with the help of spectroscopic means

Bio-transformation of Gibberellin 20,19-lactones by Rhizopus stolonifer

In a study of the stereo-electronic requirements for microbiological hidroxylation by Rhizopus stolonifer, ent-19-hydroxygibberell-16-en-20-oic acid 20,19-lactone. ent-7,19-dihydroxygibberell-16-en-20-oic acid 20,19-lactone and ent-19-hydroxygibberell-16-en-7,20-dioic acid 20,19-lactome 7-methyl ester are shown to be hydroxylated at the 15$-position.Part of tre work was carried out under the H.E.J. Institute Karachi-University of Sussex Link Scheme. We thank Professor Atta-ur-Rahman. Dr. D.R.M. Walton and the British Council for establishing this link. We also thank the Spanish Ministry of Education for a grant.Peer reviewe