P. Srinivasa Reddy

Antibacterial Activity of Isolates from Piper longum and Taxus baccata

This study describes the antibacterial activity of the pure isolates from Piper longum (L.) (black pepper) and Taxus baccata (L.) (Yew). Three isolates of black pepper were active against Gram-positive bacteria and moderately active against Gram-negative bacteria. Each isolate was highly active against at least one particular species of bacteria; piperlonguminine (1) against Bacillus subtilis, piperine (2) against Staphylococcus aureus, and pellitorine (3) against Bacillus sphaericus. 3-(3-4-5-Trimethoxyphenyl) propionicacid (4) did not show any antibacterial activity. The isolate (--)-rhododendrol (5) of Taxus baccata (L.) inhibited Salmonella typhimurium and Pseudomonas syringae, while 4-(4-hydroxyphenyl)-butan-2-one (6) and 4-(4-hydroxyphenyl)-trans-but-3-en-2-one (7) inhibited Pseudomonas syringae and Bacillus sphaericus. It is therefore evident that all the isolates of Piper longum had antibacterial activity except 3-(3-4-5-trimethoxyphenyl) propionicacid (4), whereas isolates of T. baccata showed moderate activity.

CHEMICAL REDUCTION OF ZOANTHAMINE AND EVALUATION OF ANTIBACTERIAL ACTIVITY

Zoanthamine 1 when treated with H2/Pd-C in EtOH yielded dihydrozoanthamine 2 and on treatment with NaBH4 in dry dichloromethane yielded deoxyzoanthamine 3 and deoxytetrahydrozoanthamine 4 The structures of 2,3 and 4 were determined on the basis of spectral studies. Compounds ! , 2, 3 and 4 were tested for their antimicrobial activity. Unusual biosynthetic alkaloids of the class zoanthamine (1,2) have been increasingly becoming important because of their biological activities (3,4,5). In continuation of our search for biologically active molecules from marine organisms (6,7), we isolated zoanthamine I as major constituent from unidentified colonial zoanthid of the genus Zoanthus We report herein the preparation of zoanthamine reduced analogues and evaluation of their antimicrobial activity. Y.Venkateswarlu*, N.Srinivasa Reddy. P.Ramesh, P.Srinivasa Reddy and Kaiser Jami^ Natural Products Laboratory. Organic Division-!,^Biology Division. Indian Institute of Chemical Technology, Hyderabad 500007. India. Ρ φ

Microbial transformation of Δ9-africanene

Incubation of -africanene with fungi Aspergillus niger and Rhizopus oryzae for 8 days yielded two oxidized derivatives, 10α-hydroxy--africanene and 9α,15-epoxyafricanane. The structure of the two products were assigned by interpretation of their spectral data.

Microbial transformation of -africanene

Incubation of -africanene with fungi Aspergillus niger and Rhizopus oryzae for 8 days yielded two oxidized derivatives, 10α-hydroxy--africanene and 9α,15-epoxyafricanane. The structure of the two products were assigned by interpretation of their spectral data.

Microbial transformation of Δ915-africanene

Incubation of -africanene with fungi Aspergillus niger and Rhizopus oryzae for 8 days yielded two oxidized derivatives, 10α-hydroxy--africanene and 9α,15-epoxyafricanane. The structure of the two products were assigned by interpretation of their spectral data.