Journal of Tropical Biodiversity and Biotechnology

Understanding The Current Knowledge and Potential Research of Indonesia's Only Protected Amphibian: The Bleeding Toad (Leptophryne cruentata)

Rizki Kurnia Tohir — 2025-01-09

Globally, amphibian populations are facing a substantial decline attributed to environmental degradation and lack of public attention. Indonesia, which one of countries with the high number of amphibian species in the world, paradoxically holds the record for the highest number of data-deficient amphibians. Indonesia currently has only one protected species, the bleeding toad (Leptophryne cruentata) also categorized as Critically Endangered. Considering this, our study undertakes a comprehensive review of bleeding toad research, highlighting research gaps and identifying potential topics for future investigations. In this study, we used an electronic database to acquire relevant studies aligned with our research objectives. The literature collection process involved the utilisation of the Publish or Perish (PoP) and manual internet searches. Our documentation reveals limited literature on bleeding toads, comprising only 20 reviews, with a notable prevalence of grey literature. This underscores the critical endangerment of bleeding toads, coupled with their neglect in research endeavours. Furthermore, our examination presents limited information on crucial aspects, such as taxonomy, morphology, geographical distribution, habitat characteristics, encounter records, behaviour, protection status, threats, and bioprospecting. The research gap is exceptionally high, with only two out of the 11 research topics attaining sufficient research status. Our findings underscore the urgent need for further research in this area. We identified at least 18 potential research areas that were essential for completing the baseline data. These findings serve as a valuable resource for researchers and policymakers seeking to address the critical endangerment of bleeding toads and to formulate effective conservation strategies.

Antifeedant Activity of Limonoids from the Seeds of Lansium domesticum Corr. Against Subterranean Termite Coptotermes curvignathus

Rudiyansyah — 2025-01-10

Lansium domesticum is one of Meliaceae plants produces limonoids with various biological activities, except for anti termites. Seven limonoids, dukunolides A-D (DA-DD), F (DF), and langsatides A-B (LA and LB), each previously isolated from the seeds of L. domesticum and prepared at 5 %, together with methanol root extract (MRE) 5 % were evaluated for insecticidal activity against Coptotermes curvignathus. Fifty workers and five soldiers of C. curvignathus were tested in a No-Choice Test to determine which limonoid was the most active. Dukunolides A-D, F, langsatides A-B, and MRE showed weaker antifeedant activity than the regent 50sc (positive standart, 8.04 %), except for dukunolide B (DB) that was stronger antifeedant activity, with a 7.28 % paper weight loss and 33.3 % mortality against C. curvignathus. Conclusion, this study showed limonoid compounds that were isolated from the seeds of L. domesticum could be developed for antitermite drugs.

Enhanced Antibacterial Potential of Fractionated Bioactive Compounds Isolated from Endophytic Nigrospora oryzae UILRZ1 in Ocimum gratissimum

Rahmat Folashade Zakariyah — 2025-01-10

The recurring global health challenges due to antimicrobial resistance require an impulsive response to search for alternative drugs with strong activities against multidrug-resistant pathogens. This study evaluated and screened endophytic fungi of strong antibacterial potential from Moringa oleifera and Ocimum gratissimum. Primer pairs of ribosomal DNA's internally transcribed spacer regions (ITS1 and ITS4) were used to determine their evolutionary relationships. A principal component analysis (PCA) biplot was used to identify the most effective endophyte at a 95% confidence level (P˂0.05). Improved culture conditions for the production of bioactive metabolites was done using the Taguchi design of experiment. Considering PCA biplot analysis, Nigrospora oryzae UILRZ1 from Ocimum gratissimum was most effective against selected pathogens. Production of metabolites was optimum at pH 5, 0.3 % (w/v) protein, 6-day inoculation time, and 4-plug inoculum, while variable of highest contribution was percentage of protein used. The column and thin layer chromatography were used to fractionate the extracts after optimization of production conditions while GCMS analysis was adopted to identify the chemical compounds. The crude extract's minimum inhibitory concentration (MIC) for chosen test microorganisms was 256 μg/mL prior optimization; while fractions of partially purified optimized extract of Nigrospora oryzae UILRZ1 showed enhanced antibacterial activity against Staphylococcus aureus with a MIC of 64 μg/mL. Efficient synthesis of bioactive metabolites was significant in the enhanced antibacterial activity against S. aureus.

The Distribution and Behaviour of Lesser Whistling-Duck (Dendrocygna javanica) at Lang Sen Ramsar site in Mekong Delta Vietnam

Le Diem Kieu — 2025-01-13

This study aimed to investigate the distribution, behaviour, potential food, competitor, and potential predator of Lesser Whistling-Duck (Dendrocygna javanica) by direct observations at six sub-zones in the Lang Sen Ramsar site in the south of Vietnam, from September 2021 to August 2022. Two hundred sixty nine (269) individuals of the D. javanica were seen on site mainly in pairs and small flocks. The survey showed that Lesser Whistling-Duck often appears in areas with water lettuce and duckweed at sub-zone 9, wild rice and lotus fields at sub-zone 12, and low water level fluctuation at sub-zone 5 in the early morning and late afternoon. The food source of Lesser Whistling-Duck in the reserve Lang Sen are mainly plants (duckweed, water lettuce, young shoots or seeds of lotus, water lily, water hyacinth, and wild rice) and small animals (snail, worm, shrimp, fish, and insect). This bird species is relatively sensitive to environmental influences and their ability to perceive, reflect, and make sound depends on the size of flocks. The carnivores often damage the Lesser Whistling-Duck including black kite, greater coucal, lesser coucal, and python. They are also affected by competition for food and habitat of other waterbirds, activities of tourists, and people around the reserve. The result of observation of Lesser Whistling-Duck is a concern from new area, so it added the information on the distribution of the species, including behaviour, the potential food, competitors, predators, and human threats, which are important in managing the species.

Exploration the Potency of Copper and Dyes Multi-Resistant of Indigenous Bacteria Isolated from Cikijing River, West Java

Wahyu Irawati — 2025-01-20

Various types of textile dye have been reported to contaminate the Cikijing River, West Java, Indonesia due to its location within the industrial region of Rancaekek District. It has been understood that certain bacterial species develop copper resistance and dye decolourisation as a mechanism of stress adaptation. The study aims at isolating and characterising copper and dye resistance as well as decolourisation ability of bacteria isolated from the Cikijing River. Copper-resistant bacteria were isolated using a series dilution method on Luria Bertani media supplemented with the addition of 1-10 mM CuSO₄. Purified bacterial isolates were then tested for copper resistance onto LB agar medium supplemented with CuSO₄ concentrations ranging from 0 mM to 20 mM and decolourisation of various dyes. A total of 59 copper-resistant bacteria were successfully isolated, nine of them showed the highest copper resistance with a MIC value from 11 mM up to 16 mM CuSO₄ and resistance to 4 types of dyes up to 700 ppm. The 16S rDNA analysis showed that the nine isolates were Klebsiella sp., Klebsiella pneumoniae, Lysinibacillus boronitolerans, Lysinibacillus fusiformis, Bacillus proteoliticus, Pseudomonas stutzeri, Klebsiella variicola, Citrobacter freundii, and Klebsiella variicola. Out of nine isolates, five were found resistant to 5 mM CuSO₄ and decolourise Methylene Blue, Congo Red, and Basic Fuchsine dyes at a maximum concentration of 700 ppm.

Biodegradable Sheets from Dried Mycelia of Edible Mushrooms

Chairat Pattarasiripol — 2025-01-17

Due to its quick growth and biodegradability, mushroom mycelium has been used to create alternative materials. This study aimed to produce mycelium sheets from market-purchased edible mushrooms (Lentinus sp. and Pleurotus sp.). They were isolated and cultured in various liquid media. The production of four mycelium sheets was successful. After drying, the sheets of Pleurotus sp. using potato dextrose broth had the largest water contact angle. With a tensile strength, the sheet of Lentinus sp. using malt extract broth obtained the highest value. The dried mycelium sheet from Pleurotus sp. cultured on yeast extract broth had the greatest hardness value in the microhardness testing. After 7 days, the residual dry weight of the sheets in different conditions—soil burying, soil surface exposure, and water immersion—was less than 50% of the initial weight. This work has demonstrated the biodegradability of mycelium sheets.

Present and Future Distribution Model using MaxEnt: A Risk Map for Dengue Haemorrhagic Fever based on Aedes aegypti Mosquitoes Distribution in Malang Region, East Java, Indonesia

Zulfaidah Penata Gama — 2025-01-24

The prevalence of Dengue Haemorrhagic Fever (DHF), a disease prevalent in countries with tropical and sub-tropical climates, including Indonesia, has exhibited a notable increase over the past two decades. A study case of a region experiencing this surge is Malang Region, which situated in East Java. The transmission of DHF within individual human is facilitated by the existence of Ae. aegypti, which serves as one of the intermediate vector mosquitoes. MaxEnt modelling was employed to analyse the niche and distribution of Ae. aegypti. The results of this study demonstrated that the integration of environmental and anthropogenic variables in a combination model provided more comprehensive approach for comprehending the niche and distribution patterns of Ae. aegypti compared to relying only regarding a climatic model. Areas characterised by higher temperatures, high population density, and limited vegetation cover possess the inherent capacity to serve as suitable habitats for Ae. aegypti. According to the modelling results, the distribution of Ae. aegypti in Malang region currently encompasses approximately 14.5 % (545.5 km²) of the total area. It is projected that this distribution can potentially expand to 15.5 % (568.9 km²) by the year 2040. Several sub-districts, namely Klojen, Blimbing, Sukun, Lowokwaru, Kedungkandang, Pakisaji, and Kepanjen, have been classified as high-risk areas that require special concern. The combination model of environmental variables and anthropogenic variables provide more comprehensive approach to understand the niche and the distribution patterns of Ae. aegypti in Malang Region compared to relying solely on climate models.

Stand Structure Characteristics of Fragmented and Primary Forests and Their Correlation to Carbon Stocks

Afifi Nazeri — 2025-02-03

Stand structure contributes to forest biodiversity and productivity. The disparity of stand structure between fragmented and primary forests and how they affect carbon storage are poorly understood. This study determined differences among some stand parameters in fragmented and primary forests and the correlation between forest stand structure and carbon stock. Twenty-five replicate quadrats were established in Bukit Durang and Division 5, representing the fragmented forests, and Lambir Hills National Park and Kubah National constitute the primary forests. All trees with diameter at breast height of 10 cm and above were measured, and the tree species were recorded. Aboveground biomass was calculated and converted to carbon stock. Statistical analyses showed that tree density is comparable among the forests. However, species abundance, species dominance, basal area aboveground biomass, and carbon stocks are different . Large-diameter trees significantly contribute to carbon storage. Principal component analyses revealed basal area, tree diameter and carbon stock were positively intercorrelated and associated. Species dominance and tree density are intercorrelated and strongly associated. Conversely, the number of species is negatively correlated to species dominance and tree density. This study showed the significance of tree diameter in impacting carbon stock.

Utilising Plant Extracts as Lures to Capture Ambrosia Beetles (Coleoptera: Curculionidae) in Cocoa Plantation

Sylvia Sjam — 2025-02-10

The ambrosia beetle (Coleoptera: Curculionidae) is a significant pest affecting cocoa plants in South Sulawesi. The high intensity of their attacks poses a serious threat to cocoa production, causing plants to wilt and die. This study developed traps baited with active ingredient compounds from various plant species, including coffee, carrot leaves, fermented cocoa wood, and eucalyptus oil, and compared their efficacy with ethanol. Beetles collected in these traps were identified based on morphological characteristics using a stereo microscope. The attraction test results indicated that all treatments successfully attracted ambrosia beetles, with ethanol capturing the highest number of individuals (1391). The results showed that ethanol and other extracts could capture ambrosia beetles of various kinds. The highest number of captures was found in ethanol and carrot leaf extract treatments. Additionally, eleven species were identified: Coccotrypes sp., Diuncus quadrispinulosus, Eccoptopterus spinosus, Hypothenemus sp. 1, Hypothenemus sp. 2, Hypothenemus sp. 3, Xyleborus affinis, Xylosandru s mancus, Xylosandrus crassiusculus, Xylosandrus eupatorii, and Xylosandrus morigerus. Traps baited with carrot leaf extract were most effective in capturing Hypothenemus sp. 3. These findings underscore the importance of developing various attractant traps utilising plant chemical compounds to detect and identify ambrosia beetle species and mitigate severe crop damage.

Biodiversity and Ecosystem Services Analysis to Develop a University Botanical Garden: A Case Study in the University of Palangka Raya, Central Kalimantan

Lia Hapsari — 2025-02-14

Information on existing site characteristics both biotic and abiotic factors is mandatory to provide an initial picture for a baseline to develop a botanical garden. This study aimed to analyse the biodiversity and ecosystem services in the candidate botanical garden area as an existing site, a case study in the University of Palangka Raya (UPR) to prepare the university botanical garden development. The fieldwork was conducted in 5 transects consisting of 100 plots with a plot size of 20x20 m². The results showed that the site is categorized as a Sundaland peat swamp forest ecoregion. The peatlands thickness varies from shallow to medium and deep, with the remaining area reaching 75 % of the total campus. The floristic condition is categorized as an early stage of succession after fires, consisting of 26 plant species belonging to 25 genera and 18 families, with various potential uses. Wildlife comprised 42 species including amphibians, reptiles, birds, fishes and prawns, also insects. Three high conservation value plants and two wildlife were documented. The stand carbon storage reached 14.33 tons/ha. A botanical garden consists of both natural and artificial ecosystems, thus it is important to strategically plan in setting the plant collections layout and species enrichment efforts. The UPR botanical garden will provide the conservation of native and endemic plants of Kalimantan, with high conservation value, potentials, and local wisdom value; and provide ecosystem services for storing carbon, improving hydrological services, habitat and protection for various existing and incoming wildlife.

The Effect of Thidiazuron and Naphtalene Acetic Acid on In Vitro Development of Eria hyacinthoides (Blume) Lindl Orchid

Rita Foorantika — 2025-02-17

Eria hyacinthoides (Blume) Lindl. is an Indonesian orchid species found in Sumatra, Java, and Bali. This orchid is a sympodial orchid with flowers that has fragrant aroma, suspected containing phytochemicals for herbal medicines, so mass plant propagation is necessary. The aim of this research is to obtain the best in vitro conditions for this orchid through somatic embryos using growth regulators and analysing the structure of the Dendrobium Orchid Homeobox 1 (DOH1) homologous gene in E. hyacinthoides to Dendrobium ‘Madame Thong-In’ which is known to induce bud formation. The method used in this study: (1) the leaves of the plant spread about 20 - 30 days from shoots measuring about 6.3-6.7cm on the mother plant aged ± 8 years, stored in an incubation room with picture of 16 hours of light and 8 hours of darkness in the heat. 25 ± 1 ℃, (2) compared Murashige and Skoog, Vacin and Went, Knudson C and New Phalaenopsis growth to get the best medium, (3) added PGR to medium (Thidiazuron (TDZ) 1 - 3 mg L^-1 and Naphthalene-1-acetic acid (NAA) 1-3 mg L^-1), (4) isolate partial gen DOH1 homologous by using primer of DOH1, (5) analyse sequence of PCR products. Optimal medium for callus embryogenesis production from leave was Knudson C + TDZ 1 mg L^-1 + NAA 1 mg L^-1. Amplification of DNA fragments using degenerate primers of DOH1 resulted 175 bp, indicating similarity about 88.64 % with between the DOH1 gene structure in E. hyacinthoides and in Dendrobium ‘Madame Thong-In’.

Phenol and Tannin Contents of Fresh Phyllodes and Leaf Litter Materials from Three Acacia Species in Brunei Darussalam

Safira Jamil — 2025-02-21

Invasive Acacia species are increasingly spreading into degraded forests in Brunei Darussalam since their initial planting in the 1990s. Information on the secondary metabolites of these invasive Acacia species is important in understanding their effects on leaf litter decomposition rates of invaded forests in Brunei. This study aimed to quantify the pH, total phenolic, and total tannin content of three invasive Acacia species (Acacia auriculiformis A. cunn ex Benth., Acacia holosericea A. Cunn. Ex G. Don and Acacia mangium Willd.) and one co-occurring native heath tree species (Buchanania arborescens (Blume) Blume) in Brunei Darussalam. pH, total phenolic and total tannin contents were measured and compared between leaves of the four species, as well as between leaf types (fresh phyllodes vs. leaf litter samples). All three invasive Acacia species recorded higher pH, total phenolic and total tannin contents than the native species. High pH and total phenolic content were observed in fresh phyllodes than leaf litter samples of all studied species but no differences were observed in total tannin contents for both fresh phyllodes and leaf litter samples. Higher pH, total phenolic and total tannin contents in all Acacia species may reduce leaf palatability to herbivores and detritivores, resulting in slower degradation processes compared to the native tree species, thus potentially affecting leaf litter decomposition rates in Acacia-invaded heath forests. Overall, the study on differences in secondary compounds between species and leaf types has provided insights into the decomposition rate of Acacia species compared to the native tree species.

Impact of Global Climate Shifts on the Biodiversity and Functionality of Marine Zooplankton Communities

Angkasa Putra — 2025-02-07

The impact of climate change is one of the biggest crises facing humanity today. Not only humans are affected, but also the conditions of the marine environment, including zooplankton communities, which are a key component in the marine food chain. This study reviews the analysis of the impact of global climate shifts on biodiversity and the function of marine zooplankton communities. Specifically, the study addresses how temperature changes, ocean acidification, and other stressors affect zooplankton communities. In addition, the study includes an analysis of case studies and regional variations on the impacts of climate change on zooplankton communities, as well as discusses methodologies that can be used in studying the effects of climate change. We also evaluate existing knowledge gaps and identify future research directions that are needed. Through this latest evaluation, the research highlights the importance of continuous monitoring and a multi-stressor research approach. The study also emphasizes the importance of designing effective adaptation strategies for marine zooplankton communities, which are highly relevant to future sustainable marine conservation policies. The results of this study show the urgency of further research to maintain the integrity of marine ecosystems in facing the challenge of global climate change.