ABSTRACT
The biotransformations of cholic acid (1a), deoxycholic acid (1b), and hyodeoxycholic acid (1c) to bendigoles and other metabolites with bacteria isolated from the rural slaughterhouse of Cayambe (Pichincha Province, Ecuador) were reported. The more active strains were characterized, and belong to the genera Pseudomonas and Rhodococcus. Various biotransformation products were obtained depending on bacteria and substrates. Cholic acid (1a) afforded the 3-oxo and 3-oxo-4-ene derivatives 2a and 3a (45% and 45%, resp.) with P. mendocina ECS10, 3,12-dioxo-4-ene derivative 4a (60%) with Rh. erythropolis ECS25, and 9,10-secosteroid 6 (15%) with Rh. erythropolis ECS12. Bendigole F (5a) was obtained in 20% with P. fragi ECS22. Deoxycholic acid (1b) gave 3-oxo derivative 2b with P. prosekii ECS1 and Rh. erythropolis ECS25 (20% and 61%, resp.), while 3-oxo-4-ene derivative 3b was obtained with P. prosekii ECS1 and P. mendocina ECS10 (22% and 95%, resp.). Moreover, P. fragi ECS9 afforded bendigole A (8b; 80%). Finally, P. mendocina ECS10 biotransformed hyodeoxycholic acid (1c) to 3-oxo derivative 2c (50%) and Rh. erythropolis ECS12 to 6α-hydroxy-3-oxo-23,24-dinor-5ß-cholan-22-oic acid (9c, 66%). Bendigole G (5c; 13%) with P. prosekii ECS1 and bendigole H (8c) with P. prosekii ECS1 and Rh. erythropolis ECS12 (20% and 16%, resp.) were obtained.
Subject(s)
Bile Acids and Salts/metabolism , Hydroxysteroids/metabolism , Pseudomonas/metabolism , Rhodococcus/metabolism , Abattoirs , Ecuador , Hydroxysteroids/chemistry , Molecular ConformationABSTRACT
From the ethanolic extract of Lentinus edodes (Shiitake) eight known sterols were isolated and identified: ergosterol, ergosterol peroxide, (22E)-ergosta-5,7,9(11), 22-tetraen-3beta-ol, (22E)-ergosta-7,9(11),22-trien-3beta-ol, (22E)-ergosta-6,8,22-trien-3beta-ol, (22E)-norergosta-5,7,9,22-tetraen-3beta-ol, 3beta,5alpha-dihydroxy-(22E)-ergosta-7,22-dien-6-one, (22E)-ergosta-4,6,8(14),22-tetraen-3-one and, for the first time in mushrooms, (22E)-ergosta-6,22-diene-3beta,5alpha,8alpha-triol.
Subject(s)
Hydroxysteroids/chemistry , Hydroxysteroids/isolation & purification , Phytosterols/chemistry , Phytosterols/isolation & purification , Shiitake Mushrooms/chemistry , Cholestenones , Ergosterol/analogs & derivatives , Ergosterol/chemistry , Ergosterol/isolation & purification , Molecular StructureABSTRACT
Ten new [1-10] and three known [11-13] polyhydroxysteroids were isolated, along with four known asterosaponins [14-17], from the starfish Luidia clathrata, collected from the offshore waters of the northern Gulf of Mexico. The EtOH extracts of this starfish showed feeding-deterrent properties against marine fish, and inhibited the settlement of larvae of barnacles and bryozoans, as well as the growth of several bacteria. The structures of the new compounds were determined by interpretation of their nmr spectral data and by comparison with the spectral data of known compounds. The assignment of the configurations of the side-chain stereogenic centers of compounds 1 and 3-10 were based on the comparison of their nmr data with those of the stereoisomeric model compounds after derivatization with the chiral auxiliary MTPA reagent. Larval settlement assays conducted on ten isolated compounds revealed they are all potent inhibitors of settlement. Two of these isolated compounds inhibited the growth of several bacteria.