Journal of Tropical Biodiversity and Biotechnology
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Habitat suitability modelling of Rhacophorus reinwardtii (Schlegel, 1840) in Java, with notes on habitat characteristics from Malang, East Java
No full textThe distribution of the Reinwardt's Gliding Frog, Rhacophorus reinwardtii (Schlegel, 1840), was recently thought to be restricted in Java. Furthermore, the constant and rapid deforestation in Java highlight the significance of the frog's habitat requirements in establishing the accurate species' conservation status. This study aims to predict the suitable habitat for this species in Java and to identify the habitat characteristics in Malang Region-East Java. Using the Maximum Entropy (MaxEnt) approach, we modelled the distribution of species and examined numerous types of breeding sites in Malang Region. Our findings revealed that the species inhabits a much more restricted and fragmented habitat in Java, where it inhabits both forest and agroforestry areas.
Species Composition and Inshore Migration of the Tropical Glass Eels (Anguilla spp.) Recruiting to the Jali River, Purworejo Regency
Full text linkPurworejo Regency is located in the south coast of Java where rivers flow into the Indian Ocean. The Jali River in Purworejo becomes a migration route for eels where juvenile eels (glass eels) move from the ocean to freshwater passing through the estuary. During migration, glass eels will make efforts to survive, one of which is to manage their osmotic pressure (osmolarity). With regards to those, a study on the upstream migration of glass eels in Jali River was carried out. Glass eels samplings were conducted using hand-held lift nets at the new moon phase, from 20:00 pm to 4:00 am. Sampling stations included the estuary, a branch river, and below the dam. The osmolarity of both glass eels and media (river water) were measured. Furthermore, the chemical and physical parameters of the waters as the natural habitat for glass eels were also measured. Glass eel samples were then identified to species level. The results showed that glass eels entering the Jali River consisted of Anguilla bicolor bicolor and Anguilla nebulosa nebulosa with the former being the most common. Total length of glass eels ranged between 44.10 to 69.70 mm with total weights 0.08 to 0.54 g. Glass eel migration has a close relation with surface current and tide. The osmotic work level (OWL) of glass eels approaches 0.34 mOsm/l H2O which is close to iso-osmotic. This happened at salinity 0 o/oo so that the glass eels migrate to fresh water which has a lower salinity to achieve iso-osmotic condition.
Seed Conservation of Anaxagorea luzonensis A. Gray (Annonaceae) Through Storage Behaviour and Morphology
Full text linkFruits and seeds morphological traits and seed storage behaviour of Anaxagorea luzonensis are important for seed and plant conservation. Fruits and seeds characterization using a digital microscope and morphometry method. Seed storage behaviour was determined using 100-seed test method. The findings revealed that the colour of A. luzonensis fruit did not change and A. luzonensis seed was glossy, brittle, black in colour, 9.05 x 5.89 x 2.93 mm sized and oval. The seeds are desiccation-tolerant and are categorized as orthodox seeds. These results can become the findings of A. luzonensis seed storage behaviour, because information about it never existed before. Knowing the seed storage behaviour and seed morphology of A. luzonensis is essential so that the recommendation of conservation efforts at PBG in the future are covering the fruit, modifying the environment, breaking dormant seeds, vegetative propagation, and preserving seeds.
Morphological Variation of Diospyros spp. Native to Sulawesi Based on Vegetative Organ Characters
Full text linkResearchers about Diospyros have not extensively conducted studies on the morphological characteristics to enhance information for taxonomic hierarchy purposes. Diospyros in Indonesia has great potential for in-depth research due to its unique characteristics, particularly in Sulawesi. This research aims to fill the knowledge gap regarding investigating phenotypic variations in Diospyros, specifically in the Sulawesi region. Nine species of Diospyros from the BBG collection will be observed and described for their morphological characteristics. The results indicate 25 variations of 50 characters in morphological characteristics. Variations in morphological characters can suggest that each species adapts to the surrounding environmental conditions
First Report of Cladosporium dominicanum Zalar, de Hoog & Gunde-Cim. Infecting Whitefly on Ornamental Plants in Bali, Indonesia
Full text linkAs natural enemies, entomopathogenic fungi are essential for controlling certain plant pests, such as whitefly. Many types of entomopathogenic fungi can infect whiteflies, including those from the genera Aschersonia, Metarhizium, Beauveria, and Cladosporium. Currently, there is great interest in using entomopathogenic fungi as an environmentally friendly pest control in organic and sustainable agricultural systems. This study aimed to identify entomopathogenic fungus associated with whiteflies. Identification of entomopathogenic fungus was performed morphologically and molecularly using DNA barcoding with ITS-1 and ITS-4 as primers, in addition to sequencing and phylogenetic tree analysis. Whiteflies infected with entomopathogenic fungus were discovered on ornamental plants (Premna serratifolia, Ficus religiosa, and Ficus rumphii) in Denpasar, Bali, Indonesia from January to March 2023. We found that samples from the field had mycelium that was unbranched or sparingly branched with solitary conidiophores arising terminally from ascending hyphae or laterally from plagiotropous hyphae. Samples from PDA media had ramoconidia with darkened septa, straight and conidia in long branched chains, branching in all directions, conidia were obovoid, ovoid to limoniform. The fungal colonies had the characteristics of being grey-olivaceous, olivaceous-black, and the margins were grey-livaceous to white, gray olivaceous in colony center due to abundant sporulation. In addition, based on the BLAST nucleotide sequence from NCBI GenBank, the insect pathogen phylogenetic tree found in Denpasar, Bali, is in the same clade as Cladosporium dominicanum strain SCAU014, accession number KY827344.1. Based on morphological and molecular analysis the fungus that infects whiteflies on ornamental plants is C. dominicanum
SiDREB2-based SNAP Marker-Assisted and Multi-Trait Selection in The Early Generation of Foxtail Millet (Setaria italica L. Beauv.)
Full text linkSetaria italica L. or foxtail millet is known for its nutritious grains and adaptability to unfavorable environmental conditions. High productivity, early heading, medium stature, and tolerance to drought- or salinity stress are among the breeding objectives for foxtail millet. The objective of this study was to select F3 families of foxtail millet from the cross of Botok-10xICERI-6 by weighted selection index and assisted by SiDREB2-based SNAP marker. Genotyping of 178 F3 families using the SiDREB2-based SNAP marker resulted in 29 A/A genotypes, 121 A/G genotypes, and 28 G/G genotypes. Further evaluation was conducted on 48 F3 families consisting of 27 A/A genotypes and 21 A/G genotypes in an augmented randomized complete block design together with their parental genotypes (Botok-10xICERI-6) and three check genotypes (Mauliru-2, NTB-1, and Toraja). Plant height and heading time had high broad-sense heritability, whereas grain weight per plant had a moderate broad-sense heritability. Ten potential F3 families were selected based on a weighted selection index with 20% intensity, comprised of seven A/G genotypes and three A/A genotypes with a weighted selection index ranging from 0.84 to 3.76. The F3 family with pedigree numbers B10I6-15-136, B10I6-15-161, and B10I6-15-70 with A/A genotypes are considered putative transgressive segregants and could be continued to the next generation for further breeding process.
New Record of A Freshwater Prawn Macrobrachium sundaicum in Selat Panjang Island, Riau Province, Indonesia
Full text linkA freshwater prawn M. sundaicum, is an obligate species to acidic peat swamp. Up to the present, M. Sundaicum has only been reported in the West Kalimantan, the Riau Archipelago, and Jambi Provinces in Indonesia. The aim of this research is to determine the distribution and habitat preferences of peat swamp prawn in Selat Panjang Island, Riau Province, Indonesia. The samples were collected in seven peat swamp rivers by hand net. The study yielded one hundred specimens. The acidic peat swamp is a perfect habitat for M. sundaicum. This study provided the basic information about peat swamp prawn in Selat Panjang Island, especially their distribution and habitat preferences.
A Mini Review on Analysis of Potential Antibacterial Activity of Symbiotic Bacteria from Indonesian Freshwater Sponge: An Unexplored and A Hidden Potency
Full text linkMarine sponges have been investigated as potential bioresources because of their symbiotic relationship with microbes such as Actinobacteria that produce antibacterial substances. In contrast, a group of sponges, that inhabits freshwater environments called freshwater sponges (Order Spongillida Manconi & Pronzato, 2002) and consists of only one percent among all of the sponges’ species (Phylum Porifera Grant, 1836), has not yet intensively examined. For this reason, we screened, determined, evaluated, and reviewed by examining several databases in Scopus, Pub Med, and Google Scholar related to potential aspects of symbiotic bacteria and their antibacterial substances that can be further utilised and developed into synthesised antibacterial compounds, based on published metagenomic data of symbiotic bacteria in freshwater sponges. At the same time, we compared a composition of those freshwater symbionts to marine sponges’ symbionts whether those possess a similar composition or not. Moreover, a current report and a revisit study of freshwater sponges in East Java, initiate further direction on mapping of those symbiotic bacteria from Indonesia that can be nominated as potential groups possessing antibacterial properties.
Expression, Characterisation and Structural Homology Modelling of Recombinant Mercuric Reductase of Streptomyces sp. AS2
Full text linkMercury pollution poses a significant environmental challenge worldwide, prompting extensive efforts over the past two decades to combat its detrimental effects. Cloning merA from Streptomyces sp. AS2 (Accession numbers LC026157) into the expression vector pET-28c (+) marks a critical advancement in this field, necessitating further investigation into the expression and structural analysis of the resulting recombinant mercuric reductase protein. This study aimed to optimise the expression and characterise the structural MerA protein. The study involved the expression of merA from AS2 isolate in the host Escherichia coli BL21 and the measurement of mercuric reductase using SDS-PAGE. Induction of E. coli BL21 was optimized by adding IPTG concentration and incubation time. Purification of mercuric reductase was attempted using ammonium sulphate precipitation, dialysis, and column chromatography. Protein structural characterisation was conducted using computational modelling tools Swiss-Model and Phyre2. Expression of merA from AS2 isolate was successfully performed in E. coli BL21, with SDS-PAGE showing a dominant band in the 55-70 kDa range using IPTG concentration 1 and 1,2 mM and 18-hour incubation time. The specific activity of mercuric reductase was obtained at an enzyme concentration of 294.07 Unit/mg. Protein structural characterisation revealed homology with Lysinibacillus sphaericus (Swiss-Model) and similar folding to c5c1Yc, a known mercuric reductase from the same species using Phyre2. The successful expression of recombinant pET-28c (+)-MerA in E. coli BL21 offers new opportunities for bioremediation efforts targeting mercury contamination.
Biotransformation of n-butanol to Fruity-Like Bio-Flavour by Indonesian Lactic Acid Bacteria
Full text linkMicrobial production of aroma compounds is a promising alternative to extracting plants or chemical synthesis. In our research, the Indonesian lactic acid bacteria (LAB) have been utilised as producing fruity-like bio flavour by biotransformation approach using n-butanol as a precursor. The aims of our research are to identify LAB- secondary metabolites categorised fruity-like bio flavour and investigate the changes of glucose, mannitol, xylose, lactic acid and acetic acid in growth medium after fermentation. Our result research showed that n-butanol could be transformed to several fruity like bio flavour such as ethyl butyrate, butyl acetate, butyl formate, ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, 2-heptanone, butyl propanoate, butyl propanoate, butyl 2-methylbutanoate, butyl isovalerate, butyl pentanoate, and butyl hexanoate. All of LABs consumed above 75% of glucose and only Lactococcus lactis KGB1 consumed all the mannitol on fermentation medium. In addition, Lactococcus lactis KGB1 produced the highest xylose, 11.87 g/L LABs produced. Based on the amount of fruity-like bio flavour compound generated, Lactobacillus fermentum WKS2, Lactobacillus fermentum KGL2, Lactococcus lactis KK4, Lactobacillus fermentum WKS3, Lactococcus lactis KGB1, and Lactobacillus fermentum KGL7 could be considered as agent fruity-like bio flavour by biotransformation approach