Musri Musman

New polyoxygenated steroids exhibiting reversal of multidrug resistance from the gorgonian Isis hippuris

Abstract Eleven new ( 5–15 ) and one known ( 4 ) polyoxygenated steroids have been isolated from two collections of the gorgonian Isis hippuris and their structures determined by spectroscopic analysis and X-ray diffraction study. Except for 15 all others were polyoxygenated gorgosterols. X-Ray study of the previously reported compound 4 demonstrated the stereochemistry of the side chain moiety to be identical with that of gorgosterol. Compound 15 was a deacetyl derivative of the known steroid 16 having a spiroketal and a lactone function. The stereochemistry of 15 was confirmed by X-ray analysis, which also established the C-22 configuration of 16 which had remained unsolved. These compounds have been tested for reversal of multidrug resistance (MDR) with cancer cells expressing P-glycoprotein (P-gp). Some of them showed moderate activity.

Bioactive compounds from coral reef invertebrates

Manzamine A (1) known as a cytotoxin exhibited potent antimalarial activity with 40% recovery 60 days after single intraperitoneal (i.p.) injection against mice infected with the malaria parasite Plasmodium berghei. Pachastrisamine (6), a simple derivative of a sphingosine, isolated from a sponge, Pachastrissa sp. showed a high level of cytotoxicity. New sesquiterpene carbonimidic dichlorides and related aldehydes (812) have been isolated as cytotoxic constituents of the sponge Stylotella aurantium and shown to have moderate cytotoxicity. Cyclic undecapeptides, barangamides AD (1316), have been isolated from the sponge Theonella swinhoei. Their structures were established by spectroscopic analysis and chemical reaction.

Spawning seasons of Rasbora tawarensis (Pisces:Cyprinidae) in Lake Laut Tawar, Aceh Province,Indonesia

BackgroundRasbora tawarensis is an endemic freshwater fish in Lake Laut Tawar, Aceh Province, Indonesia. Unfortunately, its status is regarded as critical endangered with populations decreasing in recent years. To date no information on the spawning activities of the fish are available. Therefore, this study provides a contribution to the knowledge on reproductive biology of R. tawarensis especially on spawning seasons as well as basic information for conservation of the species.MethodsMonthly sampling was conducted from April 2008 to March 2009 by using selective gillnets. The gonadosomatic index, size composition and sex ratio were assessed. The gonadal development was evaluated based on macroscopic and microscopic examinations of the gonads.ResultsThe gonadosomatic index (GSI) varied between 6.65 to 18.16 in female and 4.94 to 8.56 for male. GSI of the female R. tawarensis was higher in March, September and December indicating the onset of reproductive seasons, the GSI and oocyte size being directly correlated with gonadal development stages. Although, a greater proportion of mature male than female was detected during the study, the sex ratio showed that the overall number of female was higher than male. The ovaries had multiple oocyte size classes at every stage of gonadal development, thus R. tawarensis can be classified as a group synchronous spawner or a fractional multiple spawner.ConclusionThe spawning seasons of R. tawarensis were three times a year and September being the peak of the reproductive season and the female was the predominant sex. This species is classified as a group synchronous spawner.

The flora composition of Sabang Island, Aceh, Indonesia

We provide a checklist of Angiosperms from a rapid flora inventory of Sabang Island, Aceh, Indonesia. This inventory, conducted in April 2010, was carried out to prepare a baseline data of the floral composition in the north-western island archipelago of Aceh. In this exercise, we covered a total of 7 plots (0.2 ha each) and 120 quadrats (1x1 m each) in 7 sampling locations within the island. In total, we recorded 325 species from 211 genera of 68 families. Nine predominant families (i.e. family with ≥ 10 species) are Euphorbiaceae (32 species), Cyperaceae (19 species), Fabaceae (17 species), Moraceae (15 species), Meliaceae (13 species), Lauraceae and Sterculiaceae (12 species, respectively), Rubiaceae (11 species) and Annonaceae (10 species). The volcanic soil of the island could have played a significant role in defining species composition and their abundance. On the non-woody species’ composition and abundance, the increasing magnitude of anthropogenic activities, for example, road and pathways constructions into the forested area, could have enhanced propagule dispersal of non-native plants into the area.

Uji selektivitas ekstrak etil asetat (EtOAc) biji putat air (Barringtonia racemosa) terhadap keong mas (Pomacea canaliculata) dan ikan lele lokal (Clarias batrachus)

Abstract. This study examined the selectivity of ethyl acetate extract of putat air (Barringtonia racemosa) in controlling Pomacea canaliculata compared to local catfish (Clarias batrachus). Five concentration of putat air (25, 50, 100, 200, and 400 ppm) with triplicate were tested in this study. The powder of putat air kernel was extracted through increasing the polarity of solvent, i.e. dichloromethane, ethyl acetate, and methanol. The mortality data were analyzed using Trimmed Spearman Karber (TSK) program version 1.5. The selectivity value was calculated based on LC50 values obtained from TSK. The results showed that (1) LC50 values of putat airs kernel extract of putat air to P. canaliculata and C. batrachus were 25.00 and 87.06 ppm, respectively, (2) the selectivity value of putat airs kernel extract as molluscicide of P. canaliculata was 3.48. Key words: Pomacea canaliculata, local catfish (Clarias batrachus), putat air (Barringtonia racemosa).