BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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DYNAMICS OF MICROBIAL COMMUNITY DURING TEMPEH FERMENTATION
Get PDFTempeh is sliceable soybean-cake fermented by Rhizopus oligosporus. Various bacteria were detected in tempeh employing cultivation technique with limited information about their origin or sources. The present study aimed to examine the source/s of bacterial community in tempeh by combining metagenomics analysis and cultivation technique. Samples were obtained from a number of steps in tempeh production employing two-times boiling of soybean (WJB tempeh production). All samples were plated on Enterobacteriaceae and Lactic Acid Bacteria medium. Total DNA were extracted directly from tempeh for metagenomics analysis, employing High-Throughput Sequencing (HTS) and cloned 16S rRNA genes. Firmicutes and Proteobacteria were the predominant and second dominant bacteria existed in fresh tempeh (FT) obtained by metagenomics analysis. In contrast, cultivation technique showed that Proteobacteria was the predominant phylum, suggested that most of the Firmicutes were not culturable. FT was dominated by Lactobacillus and Acetobacter. Both FT and soaking water (SW) were dominated by same species of Lactobacillus, i.e. L. delbreuckii and L. mucosae, indicated that SW was probably the source of bacterial community established in the final product of fermentation. Predominant bacteria in starter culture (SC), Acinetobacter, was not detected in FT, indicating that bacteria in SC might not play significant role in bacterial community development in FT
EFFECTIVENESS OF INDIGENOUS ENDOMYCORRHIZAL BIOFERTILIZER PROTOTYPE ON ORGANIC SALAK (Salacca zalacca) PLANTATIONS AND ITS EFFECT ON NUTRIENT AND CARBOHYDRATE CONTENT OF LEAVES
No full textOrganically cultivated salak (Salacca zalacca) on dry land has limited production in Bali. Typically, fertilization is carried out using leaf litter or other organic fertilizers because soil fertility is low for salak plantations. The present study analyzed the effectiveness of an indigenous endomycorrhizal biofertilizer on the nutrient and total carbohydrate content of salak leaves and fruits. The study used a randomized block design with nine replicates. The treatment consisted of three levels, i.e., (1) fertilization with leaf litter only, as practiced by farmers and used as the control (C); (2) fertilization with an indigenous endomycorrhizal biofertilizer prototype (P); and (3) combined fertilization with leaf litter and an indigenous endomycorrhizal biofertilizer prototype (PM). Spores of indigenous endomycorrhizae from salak plantations were used to prepare the biofertilizer prototype. The results showed that the P and PM treatments provided beneficial results, such as: (1) significantly increasing chlorophyll content, relative water content of leaves, and the number and weight of fruits per tree; (2) improving fruit quality by increasing sweetness and weight per fruit; and (3) having a positive effect on water uptake and nutrient absorption, as indicated by high N and P contents in leaf tissue and high carbohydrate content in leaves
BEARDLESS BARB Cyclocheilichthys apogon (VALENCIENNES, 1842) (CYPRINIFORMES: CYPRINIDAE) IN MADURA ISLAND, INDONESIA
Get PDFThe freshwater fish Beardless Barb Cyclocheilichthys apogon (Valenciennes, 1842) is a native species of Southeast Asia, including the western Indonesia area (Borneo, Sumatra, and Java). Previously, the species was found only in the mainland of Java Island. This paper provides the first record of C. apogon in the Lembung River, one of the major rivers in Madura Island, Indonesia, thereby extending the species distribution up to 150 km northeast from the place of earlier record. The specimens of C. apogon were characterized as follows: dorsal fin rays 12; anal fin rays 8–9; pectoral fin rays 17–18; lateral line scales 34–35. A detailed description of the morphological characters of the specimen is provided in this manuscript
SEA RANCHING OF Holothuria atra: STOCKING DENSITY AND TIME
Get PDFStrong market demand, uncontrolled exploitation, and inadequate fisheries resource management have caused the overexploitation of sea cucumbers. Hence, sea ranching has been suggested as an intervention to overcome, or at least minimize, this problem. Since stocking density is one of the most important considerations in sea cucumber rearing, this study aimed to determine the optimal stocking density for the ranching of Holothuria atra. Individuals of H. atra were collected from Panjang Island, Jepara waters, and reared in bottom cages in Teluk Awur waters, Jepara, at densities of 30, 20, or 10 individuals per cage measuring 2 × 2 × 1.8 m (with a bottom area of 4 m²). Stocking of H. atra was conducted three times: at the time of cage installation, during the second month, and during the third month after installation. Characteristics of the bottom sediment (i.e., chlorophyll a, chlorophyll b, phaeophytin, and total carotene) in the sea cucumber habitat, as well as water quality parameters within the cages, were measured monthly. The results showed that the growth of H. atra fluctuated throughout the rearing period. Low stocking density resulted in higher individual weight gain compared to high stocking density. The highest weight gain was observed at a stocking density of 10 individuals per cage during the second stocking month. The highest survival rate (93%) was recorded at a stocking density of 30 individuals per cage during the third stocking month, considering that the sea cucumbers were reared for only three months. The highest mortality occurred at a stocking density of 20 individuals per cage. A low survival rate of 45% was observed during the first stocking period, or after the fifth month of rearing. Fission was observed among H. atra reared in the cages, resulting in smaller individuals. Among the measured parameters, sediment chlorophyll a, chlorophyll b, phaeophytin, and carotene concentrations fluctuated with rearing duration due to feeding activity and bioturbation by sea cucumbers. Overall, the results of this study suggest that a low stocking density of H. atra during the second stocking month promotes higher growth rates
GROWTH OF BLACK SOLDIER FLY LARVAE ( Hermetia illucens ) FED WITH PAK CHOI ( Brassica chinensis ) AND CARP ( Cyprinus carpio ) RESIDUES
Get PDFOne main drawback of the local animal industry is the inavailability of affordable and sustainable protein supply for the livestock. Insect larvae, such as the Black Soldier Fly (Hermetia illucens) larvae (BSFL), have been considered as a protein source which can be produced at a large scale using low cost organic wastes as feeding material. This study was designed to determine the response of BSFL to various waste combinations of vegetable and animal remains, Pak Choi (Brassica chinensis) residues (S) and carp (Cyprinus caprio) fish offal (I)). A total of 540 BSFL were fed with 100 mg/larvae/day combination of vegetable wastes: animal waste 70%: 30% (S > I), 50%: 50% (S = I), and 30%: 70% (S < I). Among the feed combinations, the S < I group showed the best results as it produced the significantly highest weight of BSFL at 122.8 mg/larvae and approximate digestibility of 62.01%, with the least pupae mortality rate at 4.29%
SPECIES DIVERSITY OF SOIL FUNGI FROM A CORN PLANTATION AT ECHAGUE, PHILIPPINES
Get PDFSoil fungi are a critical component of agroecosystems and provide ecological services affecting food and bioproduct production. Awareness of the composition and distribution of local species is necessary to maximize the productivity and sustainability of agroecosystems. This study aimed at isolating fungi from soil samples collected from a corn plantation at Echague, Isabela, morphologically defining, characterizing, and determining the diversity of fungal isolate species. Soil samples from five (5) different sampling units were collected, and microbiological techniques were used to isolate the fungi. Identification was performed by morphological characterization of fungal isolates guided by taxonomic keys and textbooks. Fungal diversity was assessed using Simpson\u27s indices of diversity. Sixteen (16) fungal isolates were found; 12 were known and four (4) were unidentified. Ten (10) species belonged to the Ascomycota group, and two (2) belonged to the Zygomycota class. Aspergillus species dominated the region among all species isolated and established. Aspergillus fumigatus and Aspergillus flavus were densely populated and well distributed. A potent biocontrol agent was also identified, namely Trichoderma harzianum and Trichoderma viride. The Mucor sp. and Rhizopus stolonifer (Zygomycota fungi) were also identified
KARAMUNTING (Melastoma malabathricum) EXTRACTS ON WHITE SHRIMP (Litopenaeus vannamei) MATURITY
Get PDFLanosterol is a phytosterol that is used by crustaceans to form animal steroid hormones that play a role in shrimp reproduction. This research aims to determine the response of ovary development in white shrimp parent after being given karamunting ethanol extract. This research was carried out in several stages: (1) injecting the white shrimp every 3 days at the base of the 5th leg for 15 days with variable control doses of 0 (C), 10 mg/kg BW (T1), 7.5 mg/kg BW (T2), 5 mg/kg BW (T3), 2 mg/kg BW (T4), and 1 mg/kg BW (T5); (2) isolation of white shrimp parent ovary; (3) measurement of progesterone levels in the ovary using the radioimmunoassay (RIA) method; (4) histological observation of white shrimp parent ovary; and (5) data analysis. The statistical results of progesterone level measurements showed that administration of karamunting ethanol extract at the end of maintenance resulted in a significant difference (P < 0.05). Histological observations of gonadal development in the control, T5, and T4 treatments showed that the cells developed into previtellogenic oocytes, whereas in treatments T1, T2, and T3, ovarian cells developed into endogenous vitellogenic oocytes, and only in T1 did ovarian cells develop into exogenous vitellogenic oocytes. Statistical results of oocyte size after administration of karamunting extract at the end of maintenance were significantly different (P < 0.05). The average oocyte size at the beginning of maintenance was 15.57 ± 3.15 μm, while in the control treatment it was 25.29 ± 2.69 μm, indicating that ovarian development occurred at the end of maintenance in both the control and treatment groups. Oocyte sizes in T1 (65.65 ± 2.64 μm), T2 (63.98 ± 3.06 μm), T3 (39.12 ± 6.01 μm), T4 (28.08 ± 0.84 μm), and T5 (27.65 ± 0.71 μm) were also greater than the oocyte size at the beginning of maintenance and in the control. Based on the results of this study, it can be concluded that the lanosterol content in karamunting plants can increase progesterone hormone levels, indicating an acceleration of gonadal maturity and enlargement of oocyte size in white shrimp broodstock
NATURAL HABITAT OF BALI STARLING (Leucopsar rothschildi) IN BALI BARAT NATIONAL PARK, INDONESIA
Get PDFTropical savannas and dry forests in Indonesia are important types of ecosystems which provide habitat to support various endemic wildlife. Several of these endemic species are now seriously threatened and accordingly have high conservation status according to IUCN, including the Bali starling (Leucopsar rotschildi) which is mostly now restricted to the Bali Barat National Park. Given the high extinction risk facing such species, conservation programmes are likely to require multidisciplinary approaches that address both the biological attributes of the species itself, as well as their habitat requirements. Regrettably, for many species, their habitat ecology remains inadequately understood. The objectives of this paper are to: 1) characterise the habitat of the Bali starling in terms of structure and floristic composition; and 2) document evidence of vegetation cover changes in the Bali Barat National Park. Analysis of remote sensing imagery as well as field sampling for vegetation attributes was conducted to address these objectives. Normalized Difference Vegetation Index (NDVI) was calculated from Landsat imageries using red and near infrared bands. Tree cover percentage data were downloaded from Vegetation Continuous Fields (VCF) product from the University of Maryland’s website. Results showed that forest and savanna are the dominant land cover types in the Bali Barat National Park but their distribution is somewhat dynamic with changes in vegetation cover and greenness found across the years in which increasing cover of woody plants is the general trend. In the Bali Barat National Park, the Bali starling is mostly found at or near distinct vegetation boundaries, such as the border between savanna-forest; savanna-cropland; savanna-shrubland; settlement-cropland; and forest-shrubland. Although Cekik area had planted species that has been known to be able to provide shelter and food for Bali Starling (so was Brumbun), the bird has not been observed to be presence in the area since the 1990s. These results further confirm the importance of examining habitat patterns of endemic bird within a landscape that are influenced by multiple factors that interact in space and time. Addressing data shortage in habitat patterns within endemic species distribution is important for conservation managers developing conservation management strategies. Evaluating the remaining habitat of the species is important for conservation of Bali starling and useful for the reintroduction and release program to their natural habitat
SULFATE AMMONIUM FERTILIZER ON THE OFF-SEASON PRODUCTION OF SNAKE FRUIT (Salacca sumatrana Becc.)
Get PDFSalacca sumatrana (Becc.), known locally as the Sidimpuan snake fruit, is one of the prime local commodity specialties of Padangsidimpuan City in Sumatra. The fruit is known for its sweet, sour, and astringent taste, which differentiates it from Pondoh and Balinese snake fruits. Recently, snake fruit farmers have noticed a continuous decrease in production due to failure in fruit set, particularly during the off-season. The use of fertilization and drip irrigation during the off-season has therefore been explored as a potential solution. Hence, this research investigated the use of these methods to overcome fruit-set failure and to ensure continuous production of Sidimpuan snake fruit throughout the year. Specifically, this study aimed to determine the optimal dosage of ammonium sulfate fertilizer and the appropriate drip irrigation level to improve fruit setting during the off-season. This research employed a split-plot design, with drip irrigation as the main plot and ammonium sulfate fertilization as the subplot. The observed parameters included the number of flower and fruit bunches, fruit-set percentage, and leaf nutrient content. Drip irrigation significantly affected fruit-set percentage and the number of harvested fruit bunches. The best treatment combination was 400 g ammonium sulfate fertilizer per plant combined with drip irrigation at 3,000 mL per plant. Fertilization applied during July–September resulted in an off-season harvest that was comparable to the on-season harvest fertilized during April–June, with differences of 10.76% in fruit-set percentage and 25.65% in the number of fruit bunches. These results indicate that the application of ammonium sulfate fertilizer combined with drip irrigation can overcome fruit-set failure in Sidimpuan snake fruit, particularly during the off-season
ETHNOBOTANICAL STUDY OF DIGESTIVE SYSTEMS DISORDERS IN BADUY ETHNIC, INDONESIA
Get PDFDigestive disorders rank among the most common problems faced in Indonesia, especially for the Baduy people in Banten Province. Although the Baduy live in water-rich areas, their lack of sanitation facilities and unawareness of methods of disease prevention have prompted high morbidity and mortality rates in their communities, largely due to digestive system disorders that they continue to treat with medicinal plants. This survey was undertaken to document Baduy indigenous medicinal plants that were used to treat and prevent different types of digestive system disorders in their communities using quantitative ethnobotanical approaches. Ethno medicinal data were collected from 30 informants regarding their knowledge on medicinal plants. Quantitative approaches were used to determine the use value and informant consensus factor values of collected data. The results revealed that the Baduy currently use 54 medicinal plant species belonging to 30 families to treat digestive system disorders. Additional research is required, however, to validate the function of the medicinal plants and identify their active compounds