BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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MOLECULAR CLONING OF THE VITELLOGENIN GENE IN THE HARD-LIPPED BARB (Osteochillus hasseltii C.V.) AND PHOTOPERIOD’S EFFECTS ON GENE EXPRESSION
No full textPhotoperiod affects fish reproduction as it regulates activities of the endocrine glands, which produce the hormones needed for geonadal growth and development, gametogenesis, and reproductive cycles. This study aimed to determine the effects of photoperiod on the hard-lipped barb\u27s reproductive performance by exposing the fish to three photoperiod treatments (light hour: L, darks hour: D), namely 14L:10D (control), 8L:16D (short photoperiod) and 18L:6D (long photoperiod), with four aquaria, each containing 9 fish, serving as replicates. The fish were kept under these photoperiods for 8 weeks. Liver activity, the observable variable in the study, was evaluated by measuring vitellogenin gene expression. Normalized data were then subjected to ANOVA, followed by Tukey\u27s range test. The hard-lipped barb\u27s vitellogenin cDNA was found have a 1136 bp sequence and the vitellogenin precursors encoded cDNA comprising 378 amino acids. The vitellogenin gene in each experimental group saw a significant increase on average when exposed to longer photoperiods (P<0.05), and the highest levels of vitellogenin gene expression occurred under long photoperiods (LP, 18 h light:6 h dark). These results indicate that longer photoperiods stimulate and improve the hard-lipped barb\u27s reproductive performance
CYTOTOXIC ACTIVITY OF Anredera cordifolia LEAF EXTRACT ON HELA CELLS
No full textCervical cancer is the second most frequently occurring cancer among females worldwide. Since the best strategy against cancer is to kill cancer cells without endangering normal cells, discovering a potentially selective anticancer agent from plants has become a major focus for researchers globally. A previous study on Anredera cordifolia, known as binahong in Indonesia, revealed its cytotoxic activity on HeLa cervical cancer cells with an IC₅₀ value of 75 µg/mL. However, the selectivity of the chemical agent and its molecular target was not investigated. Therefore, this study aimed to determine the selectivity of ethanolic extract of Anredera cordifolia leaf (EAC) on Vero cells and its molecular target on HeLa cells. The extract was prepared by macerating A. cordifolia leaf powder in 70% ethanol. The viability of Vero cells was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, while the cell cycle of HeLa cells was analyzed using flow cytometry. The molecular target of the extract was further investigated using immunocytochemical staining. The results demonstrated the selective cytotoxicity of EAC against HeLa cells compared to Vero cells, with a Selectivity Index (SI) of 17.36. The extract induced cell cycle arrest at the G1/S phase and suppressed Bcl-2 expression, an anti-apoptotic protein that also regulates cell cycle progression. These findings support the potential use of A. cordifolia leaf extract as a promising anticancer agent against cervical cancer, particularly HeLa cells
FIRE SPOT IDENTIFICATION BASED ON HOTSPOT SEQUENTIAL PATTERN AND BURNED AREA CLASSIFICATION
No full textIndonesia has the world\u27s largest tropical peatlands of about 14.9 million hectares that have important life support roles. However, fire frequently occurs in peatlands. According to experts and field forest firefighters, fire hotspots that appear in a sequence of two to three days at the same location have a high potential of becoming a forest fire. This study aimed to determine the sequential patterns of hotspot occurrences, classify satellite image data and identify the fire spots. Fire spot identification was done using hotspot sequence patterns that were overlaid with burned area classification results. Sequential pattern mining using the Prefix Span algorithm was applied to identify sequences of hotspot occurrence. Maximum Likelihood method was applied to classify Landsat 7 satellite images toward identifying burned areas in Pulang Pisau and Palangkaraya in Central Kalimantan and Pontianak in West Kalimantan. Sequence patterns were overlaid with image classification results. The study results show that in Pulang Pisau, 26.19% of sequence patterns are located in burned areas and 72.62% sequence patterns were found in the buffer of burned area within a radius of one kilometer. As for Palangkaraya, there were 62.50% sequence patterns located in burned areas and 87.50% sequence patterns in the buffer of burned area within the radius of one kilometer. In total, there were 72.62% and 87.50% fire hotspots recorded in Pisau and Palangkaraya, respectively, which are strong indicators of peatland fires
FLORA DIVERSITY, COMPOSITION AND ECOLOGY IN BESIQ BERMAI TROPICAL FOREST OF DAMAI DISTRICT, EAST KALIMANTAN
Get PDFBesiq Bermai Forest is part of Kalimantan forests known for vast plant diversity. The present study aimed to investigate flora diversity, composition, and ecology in Besiq Bermai Forest to support the management of biodiversity and forest conservation. Thirteen plots were established with different sizes of plots (100 m x 20 m plots for trees; 40 m x 5 m plots for saplings; and 5 m x 5 m plots for understory). Data recorded included plant species name and individual number of each plant species. Data analysed were Shannon-Wiener diversity index, Relative Density, Relative Frequency, Relative Dominance and Important Value Index. The principal component analysis (PCA) was performed to determine relationship between edaphic components and flora occurrence. The results showed that there were 93 species of trees (belonging to 48 genera and 22 families), 112 species of saplings (belonging to 62 genera and 43 families), and 48 species of understory (belonging to 28 genera and 20 families). Shannon-Wiener diversity index (H’) were 6.05, 6.25 and 3.26 for tree, saplings and understory, respectively. The most common family for tree and saplings in the forest ecosystem in this area was Dipterocarpaceae (Shorea spp). Species of tree with the highest importance value index were Dillenia excelsa, Syzygium sp. and Shorea parvifolia. The highest importance value index for species of saplings were Macaranga triloba and Shorea parvifolia; and for species of understory were Phrynium jagorianum. Ecological (edaphic) factors affecting the occurence and establishment of flora in Bermai forest were total N and C/N ratio. The present study has implication for the management of biodiversity and forest conservation
MODELLING NATURAL MORTALITY OF TROPICAL PLANTATION SPECIES Acacia mangium Willd.
No full textNatural mortality of trees is extremely variable due to the uncertainty and complexity of the functioning of forest ecosystems. The objective of this study was to develop a stand-level mortality model for Acacia mangium species by relating mortality to stand variables that affect the natural mortality process. The model was developed using data from l97 permanent sample plots measured periodically at 1-yr time intervals from 2-4 years until 8-11 years after planting in South Sumatra, Indonesia. The model consists of two complementary equations. The first equation is a logistic function predicting the probability of mortality incidence depending on stand density, site index and stand age. The second equation estimates the reduction in the number of surviving stems observed in a stand where natural mortality occurs. Nine equations were fitted using data from permanent sample plots where trees died over the time period and the best model was selected. Estimates from this second model were then adjusted by a factor equal to the probability of mortality applying three different approaches: probabilistic two-step, deterministic threshold and stochastic. All methods revealed no significant difference between the observed and the predicted number of surviving stems per ha. The probabilistic two-step approach, however, produced more consistent and the most accurate estimates. This method should provide reliable prediction when it is to be used in forest productivity prediction and management system for the species
JABON (Anthocephalus cadamba Roxb.) POTENCY FOR REMEDIATING LEAD (Pb) TOXICITY UNDER NUTRIENT CULTURE CONDITION
Get PDFInformation on metal adaptation in plants is essential to understand the mechanism of heavy metal remediation, including lead (Pb), mediated by forest plants in contaminated land. This study aimed to identify the adaptation mechanism of jabon (Anthocephalus cadamba Roxb.) seedlings to excessive lead levels based on the tolerance index of growth performance and lead transport to plant tissue. The seedlings were exposed to lead Pb(NO₃)₂ at concentrations of 0, 0.5, 1, 1.5, 5, and 10 mM in nutrient culture for 15 days. The results showed that the tolerance index (TI) of the seedlings significantly decreased with Pb exposure up to 1.5 mM, although the TI values remained above 75%. All seedlings died at Pb concentrations of 5 mM and above. Lead accumulated in all parts of the seedlings, with the highest concentration found in the leaves (735.9 ppm) under 0.5 mM Pb exposure. Pb was transported to the upper portion of the seedlings, as indicated by a transport factor (TF) greater than 1. The results suggest that jabon can tolerate excessive Pb exposure up to 1.5 mM and has potential as a phytoremediator plant
ENZYME ACTIVITY IN RELATION TO TOTAL K, Ca, Mg, Fe, Cu AND Zn IN THE OIL PALM RHIZOSPHERE OF RIAU’S PEATLANDS, INDONESIA
No full textEnzyme activity can be used as an indicator of peat decomposition in the oil palm rhizosphere of peatlands. Oil palm plantation management requires fertilization in the rhizosphere to provide nutrients for oil palm growth. The state of total nutrients in the rhizosphere can influence enzyme activity. This research aimed to study enzyme activity in relation to nutrient content in the oil palm rhizosphere of peatlands. Using the explorative method in Riau\u27s tropical peatlands, an oil palm plantation was chosen as the main site, and a degraded forest as well as a shrubland were chosen as comparison sites. In the oil palm plantation, peat samples were taken from peat adhering to oil palm roots at depths of 0–25 and 25–50 cm and at distances of 0–1, 1–2, 2–3, and 3–4 m from the trees. In the degraded forest and shrubland, samples were taken from selected plant roots at depths of 0–25 and 25–50 cm. The triplicate peat samples were then composited for analysis of enzyme activity and total nutrient content. Results showed that enzyme activity (urease, phosphatase, β-glucosidase, and laccase) in the oil palm rhizosphere decreased as the distance from trees and the depth of the rhizosphere increased. The decline in enzyme activity was caused by low peat pH and increased water content as well as organic carbon content. Enzyme activity increased with increasing oil palm age and ash content. Total K and Zn contents showed no correlation with enzyme activities. However, total Ca and Mg contents showed a positive correlation only with β-glucosidase activity. Total Fe and Cu contents showed a significantly negative correlation with enzyme activities (urease, phosphatase, β-glucosidase, and laccase). Enzyme activity in the rhizosphere of the degraded forest and shrubland was mostly lower than in the oil palm rhizosphere
PRODUCTION AND CHARACTERIZATION OF BIOSURFACTANTS PRODUCED BY Pseudomonas aeruginosa B031 ISOLATED FROM A HYDROCARBON PHYTOREMEDIATION FIELD
Get PDFThe biosurfactants are used by several industrial sectors such as petroleum, agriculture, food production, chemistry, cosmetics, and pharmaceuticals. Because of their hydrophobic and hydrophilic moieties, they have potency to reduce surface tension, interfacial tension between water-hydrocarbon systems, and low micelle concentration. Their characteristics strongly depend on the producer strain as well as on the medium composition, such as carbon and nitrogen sources. This study was conducted to investigate the influence of different sources of carbon (n-hexadecane, glycerol and glucose) and nitrogen (urea, NH4Cl and NaNO3) for the production of biosurfactants by a new strain of Pseudomonas aeruginosa B031 isolated from a rhizosphere of Paraserianthes falcataria L. Nielsen, a hardwood plant species at a phytoremediation field. The biosurfactant characteristics of the strain were evaluated, particularly its surface-active properties and potential to remove hydrocarbon. Glycerol was found to be the optimum carbon source, with rhamnose concentration, emulsification index, and critical micelle concentration (CMC) of 718 mg/L, 37%, and 35 mN/m, respectively. NaNO3 was observed as the optimum nitrogen source, with rhamnose concentration, emulsification index, and CMC of 290 mg/L, 30%, and 24 mN/m, respectively. These biosurfactants efficiently reduced surface tension of culture broth from 42 mN/m to 31 mN/m for the glycerol treatment and from 37 mN/m to 24 mN/m for the sodium nitrate treatment. The crude biosurfactants from the glycerol and sodium nitrate treatments also removed 87.5% and 84%, respectively, of crude oil from sand. These rates were higher than those of the chemical surfactants (SDS and Triton X-100). These findings indicate that the biosurfactants produced by the strain from both glycerol and NaNO3 treatments can efficiently decrease the interfacial tension of culture broth dilution and have a high emulsion index, thus hold promise in hydrocarbon bioremediation application
ANTIMICROBIAL AND HERBICIDAL PROPERTIES OF THE FRUTICOSE LICHEN Ramalina FROM GUIMARAS ISLAND, PHILIPPINES
No full textLichens, a unique symbiosis between a mycobiont and a photobiont organism, are known to produce metabolites that can be tapped as biopesticides for agriculture. Such property of the fruticose lichen Ramalina collected within Guimaras Island, Philippines was investigated in this study. A total of 195 specimens were collected and characterized using conventional morphological and chemical analyses. These lichens were identified as Ramalina farinacea, R. roesleri, and R. nervulosa. To test their potential application in agriculture, nine lichen specimens were extracted with acetone and assayed for its inhibitory activities against test bacteria, fungi, and weedy plants. All nine lichen extracts inhibited Pseudomonas aeruginosa (>19 mm ZOI) while only seven lichen extracts inhibited Staphylococcus aureus (13–19 mm ZOI). No inhibitory activity was observed among the fungal plant pathogens Fusarium oxysporum, F. solani, F. verticillioides, Colletotrichum capsici, and C. gleosporioides, and on the Gram-negative bacteria Escherichia coli and Pectobacterium carotovorum var. carotovorum. A decrease in the root (up to 27% reduction) and shoot (up to 39% reduction) lengths, and leaf chlorophyll content (up to 44% reduction) of rice weeds Fimbristylis miliacea, Leptochloa chinensis and weedy rice (Oryza sp.) were also observed. These results, therefore, suggested that the lichen crude extract from Ramalina is a potential biological control for weed management
THE GROWTH STRATEGIES ANALYSIS OF TEN WOODY PLANT SPECIES FOR EFFECTIVE REVEGETATION
No full textThe growth strategies of plant species reflect their ecological roles, as expressed through their adaptations to environmental conditions and competitive abilities. These strategies are essential for evaluating the effectiveness of revegetation efforts. However, growth strategies of plant species across different habitat types have not been fully investigated. This study aimed to examine the growth strategies of ten woody plant species naturalized from mangrove to lowland habitats in relation to their effectiveness in revegetation programs. Seedling growth was monitored for four months at the Purwodadi Botanic Garden–LIPI from October 2014 to February 2015. A completely randomized design with plant species as treatments and three replications was applied to evaluate relative growth rates (RGRs), their components, leaf nitrogen productivity, and overall growth strategies. The results showed that RGRs varied among the ten woody plant species. Pearson correlation analysis indicated that net assimilation rate (NAR) and two root-related ecological traits—nitrogen productivity and specific root length (SRL)—were strongly correlated with RGR. Heritiera littoralis, Diospyros discolor, Antidesma bunius, Schleichera oleosa, Madhuca longifolia, and Syzygium cumini exhibited high RGRs but low specific leaf area (SLA). Barringtonia asiatica showed relatively low RGR and SLA, whereas Dracontomelon dao exhibited high RGR and SLA. These findings indicate that most of the studied species, except D. dao, achieve high growth rates and competitive ability by developing fine root systems that enhance nutrient uptake. Most woody species were well adapted to dry lowland habitats, while D. dao showed greater potential to dominate the ecosystem. Furthermore, D. discolor and S. oleosa are highly recommended for revegetation of degraded tropical lowland areas