Showing papers by "Indonesian Institute of Sciences published in 2006"

Frictional Afterslip Following the 2005 Nias-Simeulue Earthquake, Sumatra

Abstract: Continuously recording Global Positioning System stations near the 28 March 2005 rupture of the Sunda megathrust [moment magnitude (M_w) 8.7] show that the earthquake triggered aseismic frictional afterslip on the subduction megathrust, with a major fraction of this slip in the up-dip direction from the main rupture. Eleven months after the main shock, afterslip continues at rates several times the average interseismic rate, resulting in deformation equivalent to at least a M_w 8.2 earthquake. In general, along-strike variations in frictional behavior appear to persist over multiple earthquake cycles. Aftershocks cluster along the boundary between the region of coseismic slip and the up-dip creeping zone. We observe that the cumulative number of aftershocks increases linearly with postseismic displacements; this finding suggests that the temporal evolution of aftershocks is governed by afterslip.

Plate-boundary deformation associated with the great Sumatra–Andaman earthquake

Abstract: The Sumatra–Andaman earthquake of 26 December 2004 is the first giant earthquake (moment magnitude M_w > 9.0) to have occurred since the advent of modern space-based geodesy and broadband seismology. It therefore provides an unprecedented opportunity to investigate the characteristics of one of these enormous and rare events. Here we report estimates of the ground displacement associated with this event, using near-field Global Positioning System (GPS) surveys in northwestern Sumatra combined with in situ and remote observations of the vertical motion of coral reefs. These data show that the earthquake was generated by rupture of the Sunda subduction megathrust over a distance of >1,500 kilometres and a width of <150 kilometres. Megathrust slip exceeded 20 metres offshore northern Sumatra, mostly at depths shallower than 30 kilometres. Comparison of the geodetically and seismically inferred slip distribution indicates that ~30 per cent additional fault slip accrued in the 1.5 months following the 500-second-long seismic rupture. Both seismic and aseismic slip before our re-occupation of GPS sites occurred on the shallow portion of the megathrust, where the large Aceh tsunami originated. Slip tapers off abruptly along strike beneath Simeulue Island at the southeastern edge of the rupture, where the earthquake nucleated and where an M_w = 7.2 earthquake occurred in late 2002. This edge also abuts the northern limit of slip in the 28 March 2005 M_w = 8.7 Nias–Simeulue earthquake.

Controlled Arrangement of Nanoparticle Arrays in Block-Copolymer Domains

Abstract: This Review describes recent results on the precise spatial distribution control of metal and semiconductor nanoparticles into domains of microphase-separated block copolymers. Specific focus is directed towards selective incorporation into a specific microphase of a block copolymer. Details on theoretical aspects concerning nanoparticle incorporation as well as practical examples are given. Furthermore, examples on applications and technological aspects of the resulting nanoparticle/polymer nanocomposites are provided.

Deformation and Slip Along the Sunda Megathrust in the Great 2005 Nias-Simeulue Earthquake

Abstract: Seismic rupture produced spectacular tectonic deformation above a 400-kilometer strip of the Sunda megathrust, offshore northern Sumatra, in March 2005. Measurements from coral microatolls and Global Positioning System stations reveal trench-parallel belts of uplift up to 3 meters high on the outer-arc islands above the rupture and a 1-meter-deep subsidence trough farther from the trench. Surface deformation reflects more than 11 meters of fault slip under the islands and a pronounced lessening of slip trenchward. A saddle in megathrust slip separates the northwestern edge of the 2005 rupture from the great 2004 Sumatra-Andaman rupture. The southeastern edge abuts a predominantly aseismic section of the megathrust near the equator.

Source parameters of the great Sumatran megathrust earthquakes of 1797 and 1833 inferred from coral microatolls

Abstract: Large uplifts and tilts occurred on the Sumatran outer arc islands between 0.5° and 3.3°S during great historical earthquakes in 1797 and 1833, as judged from relative sea level changes recorded by annually banded coral heads. Coral data for these two earthquakes are most complete along a 160-km length of the Mentawai islands between 3.2° and 2°S. Uplift there was as great as 0.8 m in 1797 and 2.8 m in 1833. Uplift in 1797 extended 370 km, between 3.2° and 0.5°S. The pattern and magnitude of uplift imply megathrust ruptures corresponding to moment magnitudes (M_w) in the range 8.5 to 8.7. The region of uplift in 1833 ranges from 2° to at least 3.2°S and, judging from historical reports of shaking and tsunamis, perhaps as far as 5°S. The patterns and magnitude of uplift and tilt in 1833 are similar to those experienced farther north, between 0.5° and 3°N, during the giant Nias-Simeulue megathrust earthquake of 2005; the outer arc islands rose as much as 3 m and tilted toward the mainland. Elastic dislocation forward modeling of the coral data yields megathrust ruptures with moment magnitudes ranging from 8.6 to 8.9. Sparse accounts at Padang, along the mainland west coast at latitude 1°S, imply tsunami runups of at least 5 m in 1797 and 3–4 m in 1833. Tsunamis simulated from the pattern of coral uplift are roughly consistent with these reports. The tsunami modeling further indicates that the Indian Ocean tsunamis of both 1797 and 1833, unlike that of 2004, were directed mainly south of the Indian subcontinent. Between about 0.7° and 2.1°S, the lack of vintage 1797 and 1833 coral heads in the intertidal zone demonstrates that interseismic submergence has now nearly equals coseismic emergence that accompanied those earthquakes. The interseismic strains accumulated along this reach of the megathrust have thus approached or exceeded the levels relieved in 1797 and 1833.

Uplift and subsidence associated with the great Aceh‐Andaman earthquake of 2004

Abstract: Rupture of the Sunda megathrust on 26 December 2004 produced broad regions of uplift and subsidence. We define the pivot line separating these regions as a first step in defining the lateral extent and the downdip limit of rupture during that great M_w ≈ 9.2 earthquake. In the region of the Andaman and Nicobar islands we rely exclusively on the interpretation of satellite imagery and a tidal model. At the southern limit of the great rupture we rely principally on field measurements of emerged coral microatolls. Uplift extends from the middle of Simeulue Island, Sumatra, at ~2.5°N, to Preparis Island, Myanmar (Burma), at ~14.9°N. Thus the rupture is ~1600 km long. The distance from the pivot line to the trench varies appreciably. The northern and western Andaman Islands rose, whereas the southern and eastern portion of the islands subsided. The Nicobar Islands and the west coast of Aceh province, Sumatra, subsided. Tilt at the southern end of the rupture is steep; the distance from 1.5 m of uplift to the pivot line is just 60 km. Our method of using satellite imagery to recognize changes in elevation relative to sea surface height and of using a tidal model to place quantitative bounds on coseismic uplift or subsidence is a novel approach that can be adapted to other forms of remote sensing and can be applied to other subduction zones in tropical regions.

Adaptive radiation and hybridization in Wallace's Dreamponds: evidence from sailfin silversides in the Malili Lakes of Sulawesi

Abstract: Adaptive radiations are extremely useful to understand factors driving speciation. A challenge in speciation research is to distinguish forces creating novelties and those relevant to divergence and adaptation. Recently, hybridization has regained major interest as a potential force leading to functional novelty and to the genesis of new species. Here, we show that introgressive hybridization is a prominent phenomenon in the radiation of sailfin silversides (Teleostei: Atheriniformes: Telmatherinidae) inhabiting the ancient Malili Lakes of Sulawesi, correlating conspicuously with patterns of increased diversity. We found the most diverse lacustrine species-group of the radiation to be heavily introgressed by genotypes originating from streams of the lake system, an effect that has masked the primary phylogenetic pattern of the flock. We conclude that hybridization could have acted as a key factor in the generation of the flock's spectacular diversity. To our knowledge, this is the first empirical evidence for massive reticulate evolution within a complex animal radiation.

Plant growth-promoting bacteria as biofertilizer

Abstract: Seventeen rhizobacteria isolated from different ecological regions, i.e. Brazil, Indonesia, Mongolia and Pakistan were studied to develop inoculants for wheat, maize and rice. Almost all the bacterial isolates were Gram-negative, fast-growing motile rods and utilized a wide range of carbon sources. These isolates produced indole-3-acetic acid at concentrations ranging from 0.8-42.1 μg/ml, irrespective of the region. Fifteen isolates fixed N at rates ranging from 20.3-556.8 nmole C 2 H 2 reduced/h/vial. Isolate 8N-4 from Mongolia produced the highest amount of indole-3-acetic acid (42.1 μg/mL), produced siderophores (0.3 mg/mL) and was the only isolate that solubilized phosphate (188.7 tag P/mL). Inoculation of the wheat variety Orkhon with 8N-4 isolate resulted in the maximum increase in plant biomass, root length, and total N and P contents in plants. Random amplified polymorphic deoxyribonucleic acid (RAPD) analysis, conducted with 60 decamer primers, revealed a high level of polymorphism among the bacterial isolates from different geographic regions and a low level of polymorphism among isolates from the same region. The complete 16S rRNA gene sequence analysis demonstrated that 8N-4 is a Bacillus pumilus strain (Accession number AY548949). It was concluded that Bacillus pumilus 8N-4 can be used as a bio-inoculant for biofertilizer production to increase the crop yield of wheat variety Orkhon in Mongolia.

Supercritical CO2 extraction of nutmeg oil: Experiments and modeling

Abstract: Nutmeg oil was extracted from nutmeg seed at pressures of 15–20 MPa and temperatures of 313–323 K with supercritical CO2. The effects of separation parameters such as temperature, pressure, CO2 flow rate and particle size on the extraction rate of nutmeg oil were observed. Broken and intact cells (BIC) model combined with discontinuous phase equilibrium between fluid phase and solid phase, and shrinking core model were selected to describe the extraction process. For BIC model, the initial fraction solute in broken cell to total solute in the ground particle f, dimensionless transition concentration Xc and partition coefficient K were used as fitting parameters. For shrinking core model, two effective diffusivities De were used as fitting parameters. The best fitting of De1 was from 4.33 × 10−9 to 7.69 × 10−8 m2/s and De2 was from 1.90 × 10−9 to 3.20 × 10−8 m2/s. From comparison of experimental data and models calculation, the shrinking core model could describe the experimental data well for all extraction conditions, while the BIC model could only describe the data at lower extraction yields well.

Tepidanaerobacter syntrophicus gen. nov., sp. nov., an anaerobic, moderately thermophilic, syntrophic alcohol- and lactate-degrading bacterium isolated from thermophilic digested sludges.

Abstract: Three anaerobic, moderately thermophilic, syntrophic primary alcohol- and lactate-degrading microbes, designated strains JLT, JE and OL, were isolated from sludges of thermophilic (55 °C) digesters that decomposed either municipal solid wastes or sewage sludge. The strains were strictly anaerobic organisms. All three strains grew at 25–60 °C and pH 5.5–8.5 and optimum growth was observed at 45–50 °C and pH 6.0–7.0. The three organisms grew chemo-organotrophically on a number of carbohydrates in the presence of yeast extract. In co-culture with the hydrogenotrophic methanogen Methanothermobacter thermautotrophicus, all strains could utilize ethanol, glycerol and lactate syntrophically for growth, although these compounds were not metabolized in pure culture without additional external electron acceptors. All strains could reduce thiosulphate. Quinones were not detected. The DNA G+C contents of strains JLT, JE and OL were 38.0, 37.3 and 37.7 mol%, respectively. Major cellular fatty acids of the strains were iso-C15 : 0, C16 : 0 and unsaturated species of C15 : 1. Phylogenetic analyses based on 16S rRNA gene sequences revealed that the strains belong to a deeply branched lineage of the phylum Firmicutes; the most closely related species was Thermovenabulum ferriorganovorum (16S rRNA gene sequence similarity of 88 %). The three strains were phylogenetically very closely related to each other (99–100 % 16S rRNA gene sequence similarity) and were physiologically and chemotaxonomically similar. These genetic and phenotypic properties suggest that the strains should be classified as representatives of a novel species and genus; the name Tepidanaerobacter syntrophicus gen. nov., sp. nov. is proposed. The type strain of Tepidanaerobacter syntrophicus is strain JLT (=JCM 12098T=NBRC 100060T=DSM 15584T).

Comparison of in vitro digestibility and chemical composition among sugarcane bagasses treated by four white-rot fungi

Abstract: The capabilities of four white-rot fungi to improve the digestibility of sugarcane bagasse for ruminants were determined. Bagasse was cultured with Lentinula edodes, Pleurotus eryngii, Pleurotus salmoneostramineus, Ceriporiopsis subvermispora (ATCC 90467) or C. subvermispora (CZ-3) at 26°C for 8, 12 or 16 weeks. The in vitro organic matter digestibility (IVOMD) and in vitro neutral detergent fiber digestibility (IVNDFD) in untreated bagasse were 45.6 and 40.3%, respectively. Meanwhile, the bagasse cultured with L. edodes and two strains of C. subvermispora, respectively, for 12 weeks, were elevated to 68.6 and 59.1%, 60.6 and 49.9% and 59.9 and 49.0%, respectively. In contrast, the IVOMD and the IVNDFD in bagasse cultured with P. eryngii and P. salmoneostramineus were the same or lower than those in untreated bagasse. In vitro gas production (IVGP) in bagasse cultured with L. edodes and two strains of C. subvermispora for 12 weeks was also higher than that of untreated bagasse. These changes in IVOMD, IVNDFD and IVGP demonstrate that L. edodes has a higher capability of improving the digestibility for ruminants than C. subvermispora, P. eryngii or P. salmoneostramineus.

Phylogeographic origin of Hokkaido house mice (Mus musculus) as indicated by genetic markers with maternal, paternal and biparental inheritance.

Abstract: We examined intraspecies genetic variation in house mice (Mus musculus molossinus) from the northern third of the Japanese Islands, in order to obtain evidence of the history of mouse colonization that might have shaped the current genetic diversity. We extended the previous sampling of mitochondrial cytochrome b sequence and added information from the Y-linked Sry gene and ribosomal RNA gene surveys. We distinguish mitochondrial haplotypes characteristic of the North Asian musculus subspecies group (involving M. m. musculus and M. m. molossinus) as 'MUS', and that of the Southeast Asian castaneus subspecies group as 'CAS' (although the mice resemble MUS morphologically). There was a clear geographic partition of MUS and CAS types into southern and northern Hokkaido, respectively. Conversely, on Tohoku, the MUS and CAS types were interspersed without clear geographic subdivision. In contrast to the mtDNA data, all Hokkaido and Tohoku mice examined were found to possess a unique type for the Y-linked Sry gene, specific to Korea and Japan. Restriction site analysis of nuclear rDNA probe showed a consistent distribution of MUS and CAS types, as major and minor components, respectively, in the Hokkaido and Tohoku mice. These data support the previous notion that the Hokkaido and Tohoku mice experienced genetic hybridization between primary residents of CAS origin and MUS newcomers arriving via a southern route. The invasion of the MUS type could correspond with the evidence for arrival of prehistoric peoples. There are, however, alternative interpretations, including genetic admixture between MUS arriving by a southern route and CAS from a northern route.

Cytotoxic lignans from the stems of Helicteres hirsuta collected in indonesia

Abstract: Optical rotations were measuredwith a Perkin-Elmer 241 automatic polarimeter. NMRspectroscopic data were recorded at room temperatureon Bruker Avance DPX 300 and DRX 400 spectro-meters with tetramethylsilane (TMS) as internal stand-ard. Electrospray ionization (ESI) mass spectrometricanalysis was performed with a 3-Tesla Finnigan FTMS-2000 Fourier Transform mass spectrometer and elec-tron impact (EI) ionization was performed with a KratosMS-25 mass spectrometer, using 70 eV ionizationconditions. LC-MS analyses were conducted using anAgilent (Palo Alto, CA, USA) LC-MSD quadrupolemass spectrometer equipped with an 1100 series HPLCand an XTerra MS C

Long-term avifaunal impoverishment in an isolated tropical woodlot.

Abstract: : Long-term (>50 years) extinction patterns and processes in isolated tropical forest patches are poorly understood. Considering that forest fragments are rapidly becoming the common feature of most tropical landscapes, data on the long-term conservation value of such fragments are urgently needed. We report on avifaunal turnover in a tropical woodlot (Bogor Botanical Gardens; 86 ha; 54% native and 46% introduced plants; mean 83,649 visitors/month) that has been surveyed several times before and after its isolation in 1936. By 2004 the original avifaunal richness of this woodlot declined by 59% (97 to 40 species) and its forest-dependent avifauna declined by 60% (30 to 12 species). Large-bodied birds were particularly prone to extinction before 1987, but following this time none of the species traits we studied could be considered predictive of extinction proneness. All seven forest-dependent bird species that attempted to colonize this woodlot by 1987 perished thereafter. Our results show that area reduction, isolation, intense human use, and perverse management (e.g., understory removal) of this patch have probably negatively affected the long-term sustainability of its forest avifauna. Resumen: Los patrones y procesos de extincion a largo plazo (>50 anos) en parches aislados de bosque tropical son poco comprendidos. Considerando que los fragmentos de bosque se estan convirtiendo en una caracteristica comun en la mayoria de los paisajes tropicales, se requieren urgentemente datos sobre el valor de conservacion a largo plazo de dichos fragmentos. Reportamos sobre el recambio anual de la avifauna en un terreno boscoso tropical (Jardines Botanicos Bogor; 86 ha; 54% plantas nativas y 46% plantas introducidas; promedio de visitantes/mes: 83,649) que ha sido muestreado varias veces antes y despues de su aislamiento en 1936. En 2004 la riqueza de especies de aves original de este terreno habia declinado en 59% (97 a 40 especies), y su fauna dependiente de bosque declino 67% (30 a 12 especies). Las aves de cuerpo grande fueron particularmente propensas a la extincion antes de 1987, pero despues de este ano ninguno de los caracteres de las especies que estudiamos podria considerarse predictivo de la propension a la extincion. Las siete especies de aves dependientes de bosque que intentaron colonizar este terreno antes de 1987 perecieron despues. Nuestros resultados muestran que la reduccion del area, el aislamiento, el uso humano intenso y la gestion perversa (e.g., remocion del sotobosque) de este parche probablemente han afectado negativamente a la sustentabilidad a largo plazo de su avifauna de bosque.

Traditonal use of medicinal herbs by local community of Wawonii island, Southeast Sulawesi

Abstract: Twice field works to Wawonii Island was carried out in 2003 and 2004, in order to collect data on utilization of medicinal plants by local people. Two villages of Wawonii, which occupied by Wawonii tribe, were selected as study sites. Based on the study of 73 plants species, which uses by local people as traditional medicine and after having child were recorded. Similar to order inland areas of Indonesia, forest clearances and process of modernization was also occurred in this study area. Consequence the effect of those activities expected will beaffect in lost of local knowledge and destruction of natural resources. For that reason a study on utilizes of medicinal plant by local people is needed.© 2006 Jurusan Biologi FMIPA UNS SurakartaKeywords: traditional medicine; Wawonii tribe; Southeast Sulawesi.

An examination of species within the genus surirella from the malili lakes, sulawesi island, indonesia, with descriptions of 11 new taxa

Abstract: With 35 taxa reported by Hustedt (1942a), the genus Surirella (Turpin) is one of the most taxonomically rich and important genera in the Malili Lakes, a system of five ancient lakes located on the island of Sulawesi, Indonesia. We examine in detail the taxonomy of diatoms within the genus Surirella from the Malili Lakes. We also statistically evaluate valve morphology and relationships among taxa, and describe 11 new taxa. Results show Surirella taxa clustered according to unique combinations of morphological characteristics. Individuals within clusters often shared common valve shape, torsion, and presence of siliceous features including spines, spinules, and novel structures such as siliceous tendrils and tubular processes along the median area. We demonstrate that the siliceous tendrils of Surirella sublinearis and its varieties, and S. tenacis are used for attachment to substrata and further postulate that the evolutionary development of attachment features contributes to the substantial diversity of ...

Distribution and ecology of leptocephali of the congrid eel, Ariosoma scheelei, around Sulawesi Island, Indonesia

Abstract: A survey for leptocephali around Sulawesi Island in the central Indonesian Seas during May 2001 found that the leptocephali of the congrid eel, Ariosoma scheelei, were present in all seven areas that were sampled. A total of 551 leptocephali (22–166 mm TL) were collected, and A. scheelei was by far the most abundant species of leptocephali collected during the survey. The wide range of sizes in most areas indicated that spawning had occurred during a period of several months in many different areas, although the exact spawning locations were not determined. The larger size classes were more abundant in all areas except in Tomini Bay on the northeast side of Sulawesi Island. The highest catch rates were observed at the eastern edge of the Java Sea and to the north in the Celebes Sea near Makassar Strait. Premetamorphic leptocephali were also collected in surface samples at 11 stations (N=62), but metamorphosing leptocephali (N=86) were only caught in IKMT tows that fished from the surface to about 200 m. Metamorphosing leptocephali were collected primarily at two stations in the Java Sea and Makassar Strait where a surface layer of lower-salinity water was detected. Their total lengths (105.3–153.3 mm) and the largest premetamorphic individuals suggested that this species can reach maximum sizes of about 165 mm before beginning to metamorphose. It is hypothesized that this species may be abundant in the Indonesian Seas region and that it has ecological traits such as large size at recruitment and a small size at reproduction that have made it successful in many regions of the Indo-Pacific.

Declining populations of the Javan warty pig Sus verrucosus

Abstract: We conducted an interview-based survey for the Javan warty pig Sus verrucosus, endemic to the islands of Java and Bawean in Indonesia. The species occurs in 10 isolated areas, although some additional, probably very small populations, may remain. Compared to a survey conducted in 1982, 17 of the 32 (53%) populations are extinct or have dropped to levels so low that local hunters have failed to encounter the species in recent years. This indicates a rapid population decline. We hypothesize that this loss is primarily caused by a decline in suitable habitat, especially stands of teak Tectona grandis forest or similar forest plantations, and by high hunting pressure. Competition from and hybridization with the Eurasian wild boar Sus scrofa may be further threats to S. verrucosus. Rapid action is needed to prevent extinction in the wild. We recommend effective pro- tection of selected S. verrucosus populations, lobbying of the Government to give protected status to S. verru- cosus, conducting ecological research and investigating crop damage issues, and establishment of conservation breeding programmes.

Ecology and conservation of endangered Javan Hawk-eagle Spizaetus bartelsi

Abstract: The Javan Hawk-eagle Spizaetus bartelsi is globally endangered species which exclusively occupies the last remnant forests of Java island, Indonesia. Studies to explore its distribution throughout the island and to uncover its eco-biology have been going on. Recent field surveys recorded new localities of the Javan Hawk-eagle at South Cianjur, West Java, at G. Sanggabuana, Karawang district, West Java and at G. Endut complex, West Java. Our understanding about this enigmatic bird of prey has been improved. Ecological research, including radio tracking, has provided information on prey species, breeding biology and the estimated home range. Small mammals such as treeshrews, squirrels, bats, rats and other small rodents are the preferred prey, but birds, snakes and lizards are also taken. The Javan Hawk-eagle may breed at anytime of the year but usually between January and July. It is sexually mature at the age of three to four years, breeds every two years and lays only one egg. Incubation lasts f...

Biochemical characteristics of chitosanase from the Indonesian Bacillus licheniformis MB-2

Abstract: Bacillus licheniformis MB-2, isolated from a hot spring water in Manado, Indonesia, secreted a unique chitosanase. Media consisted of 0.24% chitosan, 0.25% casiton, 1% MgSO4, 1.4% K2HPO4, 0.02% CaCl2·2H2O, 0.002% FeSO4·7H2O (w/v) was used for enzyme production. Purification of the enzyme through the hydrophobic interaction chromatography system (butyl Sepharose 4 FF) resulted in two major active fractions; the F2 fraction was shown as a single band at both sodium dodecyl sulfate-polyacrylamide gel electrophoresis and zymogram analysis with apparent molecular mass of 75 kDa. The enzyme worked best at 70°C and pH between 6.0 and 7.0. When incubated at 70, 80, and 90°C, the t1/2 values were 26.56, 18.44, and 16.74 min, respectively with the k constant being at 0.026, 0.037, and 0.04/min. When heated at 90°C, the enzyme retained its activity up to 8 h in the presence of 1mM MnCl2. The enzyme's activity was unaffected by the presence of 1 M NaCl and 6 M urea but was decreased by 2 M of guanidine hydrochloride. Albeit the enzyme did not degrade colloidal and glycol chitin, it hydrolyzed glycol chitosan up to 0.8% and colloidal chitosan up to 11%. The 85% deacetylated (DDA) soluble chitosan was the most susceptible to this enzyme, followed by 90% and 100% DDA chitosan. The K m app values of the 85, 90, and 100% DDA soluble chitosans were found as 0.23, 0.24, and 0.58 mg/mL, whereas the Vmax values were 843, 668, and 261 U/mg, respectively. The hydrolysis products of F2 chitosanase at 24 h incubation (70°C) were pentasaccharide (GlcN)5 and hexasaccharide (GlcN)6. The prelimiaary test showed inhibitory effect of chitooligosaccharides resulted from enzymatic degradation toward Pseudomonas aeruginosa, Salmonella typhimurium. Listeria monocytogenes, Bacillus cereus, Escherichia coli, and Staphylococcus aureus.

Eulophine parasitoids of the genus Trichospilus in Indonesia, with the description of two new species (Hymenoptera: Eulophidae)

Abstract: Two new species of the parasitoid wasp genus Trichospilus (Chalcidoidea: Eulophidae: Eulophinae) are described from Java and Sulawesi, Indonesia. A key to all species of Trichospilus worldwide is provided.

The effect of Lactobacillus plantarum 1A-2 and 1BL-2 inoculant on the quality of napier grass silage

Abstract: Ensiling is one solution to handle lack of forage at dry and wet season in tropical area. Napier grass (Pennisetum purpureum) is a popular crop conserved as silage, regarded with a relatively high dry matter (DM) content and adequate water soluble carbohydrates for fermentation to lactic acid. The aim of this study was to determine the effect of adding lactic acid bacteria inoculants to Napier grass at ensiling on the quality of silage. Two strain lactic acid bacteria inoculants Lactobacillus plantarum 1A-2 and 1BL-2 were added to the grass at different variation of inoculants , single or mix strain (0%, 0.1%, 0.3%, 0.5%, and 1%) with 3% of rice brand as additive, and incubated for 30 days. The 1A-2 inoculants treatment lowered the pH between 3.67 to 4.18 and increased the lactate level of the grass silage 0.3 to 0.34 mg mL-1 compared with the control and other treatments. The parameters for destruction is under 5% and DM loss was considerably lower in single inoculants 1BL-2 (0.01-3.97%) and 1A-2 (0.31-5.18%). © 2006 Jurusan Biologi FMIPA UNS SurakartaKey words: silage, fermentation, potential microorganism, lactic acid bacteria

PENGARUH KONSENTRASI NITROGEN DAN FOSFOR TERHADAP PERTUMBUHAN, KANDUNGAN PROTEIN, KARBOHIDRAT DAN FIKOSIANIN PADA KULTUR Spirulinafusiformis

Abstract: An experiment was carried out to find out the optimum nitrogen and phosphorous concentration for growth and phycocyanin production in Spirulina fusiformis culture. The cultures were grown in Zarouk medium at various nitrogen and phosphorous concentrations, which were 0.0 mM N, 7.5 mM N, 15.0 mM N, 22.5 mM N, and 30.0 mM N, as well as 0 raM P, 90 mM P, 180 mM P, 270 mM P, and 360 mM P, with four replications each. The result shows that optimal growth of the alga, which is expressed in terms of the biomass yield, was achieved at nitrogen and phosphorous concentration of 7.5 mM and 270 mM, respectively.At the same time, the highest phycocyanin content was obtained at nitrogen concentration of 22.5 mM, which was 1,2% of the biomass, and phosphorous concentration of 360 mM, which was 1.1% of the biomass. According to this result, it is suggested the optimum concentration of nitrogen and phosphorous in the media of Spirulina culture for phycocyanin production is 22.5 mM and 360 mM, respectively.