Journal of Tropical Biology & Conservation (JTBC)

The Correct Scientific Name for Kacip Fatimah is Labisia pumila (Primulaceae), not Marantodes pumilum

2025-07-08T07:12:04+08:00

Differences in Seed Germination and Seedling Survival of Selected Dipterocarpaceae Species Collected from Contrasting Forest Types in Brunei Darussalam

2025-09-08T07:46:16+08:00

Microplastics Contamination in Wild Fish Caught from Urbanised Sepanggar River of Kota Kinabalu, Sabah

2024-07-15T09:43:48+08:00

Urban areas with high populations generate high levels of plastic waste from human activities, entering and raising microplastic levels in riverine systems. Microplastic contamination in rivers poses serious risks to fish through ingestion, toxicity, and bioaccumulation. Nevertheless, the paucity of previous studies on fish microplastic pollution in Sabah, Malaysia highlights the knowledge gaps in this area. Thus, this study aimed to assess microplastic pollution in fish from the urbanised Sepanggar River in Kota Kinabalu, Sabah. A total of 39 fish were caught from the river using gill nets (2-inch mesh), identified to the species level, and measured for total length, standard length, and wet weight. Samples were dissected into muscles and internal organs and digested with 10% KOH. Microplastics were then extracted using the density separation method in 5M NaCl and counted by type, colour, size, and polymer type. The present study demonstrated that microplastics were detected in 77% of fish (5.28 ± 6.51 items/fish) caught from the Sepanggar River. Small-sized microplastic fragments (54%), black (40%), and rayon (23%) were the dominant microplastics in fish. The Mann-Whitney U test revealed that microplastic abundance in internal organs (3.54 ± 3.63 items) was significantly higher than that in muscles (1.74 ± 5.10 items). The characteristics of ingested microplastics varied significantly by fish species, probably due to the different feeding habits and diets. Overall, fish in the Sepanggar River were moderately polluted by microplastics from domestic and industrial activities. Improved waste management is needed to monitor and reduce long-term microplastic contamination.

Morphological and Genetic Characterisation of Seahorse Species (Syngnathidae: Hippocampus spp.) in the Waters of Sabah, Malaysia

2024-10-21T13:37:19+08:00

Seahorse are teleosts belonging to the genus Hippocampus which consists of 57 species. Among the 57 species, only 12 species exist in Malaysian waters and 11 species in the coastal waters of Sabah. These records and checklists pre-date 2015, and no known studies or field surveys have been conducted in Sabah since then. In this study, a field survey was conducted in selected areas of Sabah waters to document the species composition through morphological and genetic identification. Out of the 11 species that were recorded previously, only two species (Hippocampus barbouri and Hippocampus comes) were found and identified using taxonomic keys. CO1 mitochondrial gene was used for genetic identification and phylogenetic tree reconstruction of Maximum Likelihood (ML). The dataset comprises sequences of 11 species from Malaysian waters (excluding H. satomiae). The genetic distances, i.e., p-distances, for H. barbouri and H. comes were recorded to be less than 1% inter-species and more than 10% intra-species, which confirmed the distinct species genetically. Furthermore, findings highlight the urgency of implementing conservation strategies to protect the remaining populations, in light of limitations of this study.

Seasonal Abundance of Common Honey Bees and Floral Resources in Mixed Agriculture and Grassland Habitats

2025-02-24T12:27:50+08:00

Bee keeping is a traditional practice has been playing significant role in sustainable development of rural and tribal communities. Diversity and abundance of honey bee depends on the floral resources available and can be influenced by seasonal environmental changes. In the present study, we investigated seasonal abundance of hives of three common honey bees Apis cerana, A. florea and A. dorsata in a draught prone area in the Karjat Taluka, Maharashtra (India) for three consecutive years. Also, the flowering plants providing floral resources and their seasonal composition were studied. The study was conducted in mixed agriculture and grassland habitats at 11 locations. The study revealed that A. florea is the most abundant species followed by A. cerana and A. dorsata and their proportion remains similar in different seasons. A total of 72 plant species were recorded with nectar and pollen as floral resources. The proportion of agriculture crop plants was high in monsoon season. The composition of flowering plants varies in different seasons. The results of the present study suggest that in mixed agriculture and grassland ecosystem support the abundance of A. florea species. The changes in the seasonal floral resources do affect the honey bee species abundance. The results of the present study will be helpful as baseline information for the sustainable development of apiculture in mixed agriculture and grassland habitat.

Rural Tourism in Kiulu, Sabah, Malaysia: A Critical Examination through The Lens of The Host Community

2025-02-10T15:09:06+08:00

Local communities often face a number of challenges when seeking to participate in rural tourism including participation in decision making, the level of empowerment the community enjoys and other factors including knowledge of tourists and local culture and the role governments play in supporting rural tourism development. To investigate these issues, a mixed methods approach was used to collect data from 118 residents of Kiulu, a rural destination in Sabah, Malaysia through questionnaires and in-depth interviews. The results show that successful rural tourism in Kiulu is driven by strategies that promote local participation in decision-making, community empowerment and better knowledge of the tourism industry. However, the study also shows that there is a lack of positive correlation between rural tourism growth and knowledge sharing, a challenge that appears to be rooted in strained relationships between tourism stakeholders. Other barriers include financial constraints, inadequate road access and the need for specialised training in tourism services. Addressing these barriers through targeted government interventions such as financial support and capacity building programmes may help distribute the benefits of rural tourism more equitably and ultimately promote sustainable development within the community.

Modulation of Oxidative Stress by Centella asiatica (L.) Urb. Leaves Against Carbon Tetrachloride-Induced Hepatic Damage in Rats

2025-06-16T10:53:09+08:00

Liver injury induced by oxidative stress remains a significant global health concern, necessitating the exploration of safe and effective hepatoprotective agents derived from natural sources. Centella asiatica (L.) Urb., frequently referred to as ‘pegaga’, is a plant renowned for its notable medicinal attributes. The primary aim of this study is to assess the antioxidant capacity and hepatoprotective activity of the ethanolic extract of C. asiatica (EECA). The assessments used to evaluate EECA for its antioxidant properties included total phenolic content (TPC), as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power assays. Additionally, the study evaluated the ability of EECA to mitigate experimentally induced hepatic injury in Sprague-Dawley rats caused by carbon tetrachloride (CCl₄) at 100, 500, and 1,000 mg/kg b.wt. doses. Biochemical assays included measuring hepatic marker enzymes alanine transaminase (ALT) and aspartate transaminase (AST) in serum, as well as evaluating malondialdehyde (MDA) and reduced glutathione (GSH) levels in liver homogenates. The TPC of EECA was 106.55 ± 2.23 mg GAE/g. Its DPPH and reducing power assays exhibited moderately potent antioxidant attributes compared to standard references. Nonetheless, groups subjected to CCl₄ displayed notably elevated levels of ALT and AST, increased MDA, and decreased GSH. Pretreatment with EECA resulted in a marginal decrease in hepatic marker enzyme activity, with reductions in ALT (14% to 2-fold), AST (25% to 3-fold), and MDA (15–57%), along with an increase in GSH (3–23%). These findings imply that EECA contains active constituents capable of mitigating the hepatotoxic effects induced by CCl₄.

Characterisation of Fruticose Lichen Genus Stereocaulon from Sabah Based on Morphology, Chemotyping, and Molecular Typing

2025-03-03T08:34:05+08:00

Lichens in the genus Stereocaulon are commonly found in high-elevation mountains in tropical regions. Taxonomy of Stereocaulon is always an ongoing topic discussed among lichenologists, especially for species-level identification due to polymorphism and chemical diversity of Stereocaulon. In this study, we examined Stereocaulon spp. from Mount Kinabalu, the highest mountain in Borneo (4095 m). A total of 42 Stereocaulon specimens were included in this study; 40 were newly collected between 1900 m and 3700 m a.s.l. along the summit trail of Mount Kinabalu, and two specimens from Mount Alab (1900 m) were previously published. We used integrative approaches to delimit the specimens into Operational Taxonomic Units (OTUs) based on macro-morphology, chemical profiles, and molecular phylogeny. Macro-morphological characters, including apothecia (reproductive organ), phyllocladia, pseudopodetia and cephalodia were examined, while chemical profiles were obtained from spot tests and High-performance thin-layer chromatography (HPTLC). A phylogenetic tree was constructed based on the ITS gene by using Bayesian and Maximum Likelihood analyses. A total of six Operational Taxonomic Units (OTUs) were identified and were provisionally named according to their diagnostic morphological and chemical characters, namely, RF (ramular-fluorescence), RN (ramular-nonfluorescence), GF (granular-fluorescence), GN (granular-nonfluorescence), RU1 (ramular-curved 1) and RU2 (ramular-curved 2). The monophyly of each of the OTUs is supported by phylogenetic analysis. Due to lack of reliable identification keys and reference genetic data for this genus, we could not determine the species identities for the OTUs revealed in this study. Nevertheless, the findings of this study provide a baseline for future studies on the taxonomy of Stereocaulon species in Mount Kinabalu, integrating morphology, chemistry, and genetics. The implementation of high-performance thin-layer chromatography (HPTLC) profiles show potential for distinguishing samples. However, further research with more Stereocaulon samples from different taxa and regions is necessary to verify the reliability of this method.

Bat (Mammalia: Chiroptera) Diversity of the Taliwas River Conservation Area, Lahad Datu, Sabah

2024-10-28T07:31:44+08:00

Understanding species diversity and distribution is essential for informing conservation strategies, particularly in lesser-explored forest habitats. This study provides the first species checklist of bats in the Taliwas River Conservation Area (TRCA), a forest reserve adjacent to the Danum Valley Conservation Area (DVCA) in Sabah, Malaysia. A four-night bat survey was conducted from June 8–11, 2022, using mist nets and harp traps placed along three forest interior trails. A total of 16 bat species comprising 61 individuals were recorded across four families: Pteropodidae (4 spp.), Rhinolophidae (6 spp.), Hipposideridae (3 spp.), and Vespertilionidae (3 spp.). The insectivorous Hipposideros cf. saevus (formerly Hipposideros ater) was the most frequently captured species (21 individuals), while Pteropus vampyrus (n = 4) was visually observed feeding on Octomeles sumatrana (Binuang) nectar near the main camp. Two species of high conservation concern were recorded: the Endangered P. vampyrus and the Vulnerable Hipposideros ridleyi. The detection of multiple forest-interior species, including individuals showing reproductive signs, suggests that the TRCA provides suitable habitat for both foraging and roosting. These results highlight the conservation relevance of the TRCA as a complementary area to the broader DVCA landscape. Future studies incorporating long-term monitoring, acoustic detection, and habitat quality comparisons between protected and adjacent modified landscapes are recommended to inform site-based conservation management.

Inventory and Assessment of Lycophytes in the Selected Forest Patches of Kalabugao, Impasug-ong, Bukidnon

2025-07-22T09:01:08+08:00

Lycophytes, a group of ancient vascular plants, represent a fascinating evolutionary lineage with significant ecological and evolutionary importance. This study was carried out to determine species composition, describe the diagnostic characteristics, and assess the conservation status and endemism of lycophyte species in Kalabugao, Impasug-ong, Bukidnon. A total of nine lycophyte species were recorded in Kalabugao, namely Phlegmariurus banayanicus Herter, Huperzia sp., Phlegmariurus salvinioides (Herter) Ching, Palhinhaea cernua (L.) Vasc. & Franco, Selaginella alligansHieron., S. involvens (Sw.) Spring, S. llanosii Hieron, S. negrosensis Hieron., and Selaginella sp. Assessment of conservation status and endemism revealed that two species are endangered (EN) and two species are of least concern (LC). This study contributes to the broader understanding of lycophyte biology and ecology, emphasizing their role in terrestrial ecosystems and their evolutionary significance.

Dereplication of Oligostilbenes in The Crude Extracts of Dipterocarpaceae Plants from Kadamaian, Sabah

2025-08-19T17:14:30+08:00

Oligostilbenes are a class of polyphenolic compounds with notable bioactivities, predominantly produced by Dipterocarpaceae, a major tree family in Southeast Asian tropical rainforests. Given their ecological and pharmacological significance, efficient identification of oligostilbenes from natural sources is essential, particularly to avoid re-isolation of known compounds. This study aimed to apply an LC-ESI-MSⁿ-based dereplication approach for the rapid identification of known oligostilbenes directly from crude extracts of Dipterocarpaceae species collected from Kadamaian, Sabah. The selected species; Parashorea tomentella, Dryobalanops lanceolata, Dipterocarpus caudiferus, Shorea xanthophylla, and Shorea seminist, represent ecologically important flora from one of the most biodiverse forest regions in Malaysia. An in-house MS¹–MS⁵ spectral database of authenticated oligostilbenes was used to match fragmentation profiles and retention times from ten crude extracts (bark and heartwood). A total of 11 known oligostilbenes were confidently identified, with species- and tissue-specific variations observed in their distribution. P. tomentella showed the richest profile in bark, while certain trimeric and tetrameric stilbenes were more prevalent in heartwood, suggesting tissue-specific biosynthetic patterns. Additionally, several unidentified peaks with consistent stilbene-like fragmentation were detected, indicating the presence of potentially novel oligostilbenes. This dereplication method significantly enhanced the speed and reliability of compound identification in complex matrices, demonstrating its utility in streamlining phytochemical workflows. The findings also provide valuable chemotaxonomic insights into the Dipterocarpaceae of Sabah and support their potential as reservoirs of bioactive natural products.

Preliminary Assessment of Secondary Metabolites of Selected Pteridophytes from Jorhat, Assam, India

2025-06-09T10:43:26+08:00

This study analyses the phytochemical constituents of seven pteridophytic species from Assam, India. The methanolic extracts of

seven species: Pyrrosia lanceolata, Pyrrosia nummularifolia, Ampheneuron opulentum, Sphenomeris chinensis, Selaginella sp., Diplazium esculentum, and Blechnum orientale were screened for phenolic, flavonoid, and flavonol content using standard spectrophotometric methods. Pyrrosia nummularifolia exhibited the highest flavonoid content, while Diplazium esculentum had the highest flavonol concentration. These bioactive compounds, known for their antimicrobial, antioxidant, and anti-inflammatory properties, support their traditional medicinal use and highlight their potential for drug discovery. Further studies are required to isolate and identify the pharmacologically active compounds from these species.

Ardisia ledangensis (Primulaceae-Myrsinoideae), a new species from southern Peninsular Malaysia

2025-09-29T11:05:16+08:00

Ardisia ledangensis Julius & Utteridge, a new species from Gunung Ledang, Johor, in the southern part of Peninsular Malaysia, is formally described and illustrated. Its placement within subgenus (§) Crispardisia is justified by diagnostic characters such as vascularised glandular nodules along the leaf margin and a terminal inflorescence borne on a lateral shoot, accompanied by a normal foliage leaf (rather than a reduced, bract-like leaf). The species is distinctive among Peninsular Malaysian members of the subgenus by its slender, descending habit, narrowly elliptic leaves densely covered with black glandular-dots, and unbranched, strictly terminal inflorescences. Ardisia ledangensis is known only from a single locality within a protected area, and its conservation status is provisionally assessed as Least Concern (LC).

Total Phenolic, Total Flavonoid and Antioxidant Activities of Durio graveolens Becc. from Sabah, Malaysia

2025-09-30T11:28:08+08:00

Sabah is home to diverse wild durian species, including the orange-fleshed durian (Durio graveolens Becc.), locally known as "dalit." Despite its prevalence, scientific data on this wild durian remains limited. This study aimed to characterise the phytochemical composition and antioxidant potential of D. graveolens fruit parts (flesh, seed, mesocarp, and exocarp). Freeze-dried samples were extracted using 80% methanol and 60% acetone, followed by qualitative phytochemical screening. Total phenolic and total flavonoid contents were quantified via the Folin-Ciocalteu and aluminium chloride colourimetric methods, respectively. Antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assays, and ferric reducing antioxidant power (FRAP) assay. The 60% acetone extracts demonstrated superior phytochemical content and antioxidant activity compared to methanolic extracts. The mesocarp exhibited the highest total phenolic (76.64 ± 1.21 mg GAE/g, p < 0.01) and flavonoid (69.30 ± 0.69 mg CE/g, p < 0.01) contents, along with the strongest antioxidant activity (DPPH IC₅₀ = 70 µg/ml, p < 0.01; ABTS IC₅₀ = 50 µg/ml, p < 0.01; FRAP = 71.15 mg TE/g, p < 0.01). These findings highlight the mesocarp’s potential as a natural antioxidant source with promising pharmaceutical applications.

A New Variety of Capparis (Capparaceae) from Northern Peninsular Malaysia

2025-10-28T17:23:55+08:00

Here we describe and illustrate Capparis scortechinii var. setiuensis, a new variety of Capparaceae, which is endemic to Terengganu, from the northern region of Peninsular Malaysia. This taxon is placed within the section Monosticocalyxcharacterised by its persistent leaves, free and dimorphic sepals in bud, with the outer pair notably larger and enclosing the inner sepals. It resembles C. scortechinii var. scortechinii in the inflorescence characteristics, where each flower is subtended by a prominent leaf-like bract and arranged in a dense racemose formation along the rachis, which is densely covered with rusty-brown hairs. However, this variety is easily recognised by its pinkish to greenish leaf-like bract with brown venation, which is glabrous and caducous soon after. Additionally, this variety can be distinguished by its completely glabrous filaments and gynophores, in contrast to var. scortechinii, which has these parts that are densely hairy at their base. An updated identification key for Peninsular Malaysian species of Capparis, along with the provisional conservation status of this taxon, is also presented.

Bird Diversity and Functional Guilds in Sg. Talibu Forest Reserve, Sabah

2025-05-13T12:52:09+08:00

A rapid avifaunal assessment was conducted in Sg. Talibu Forest Reserve, a secondary mixed dipterocarp forest in Telupid, Sabah, Malaysia. Using a modified MacKinnon List method, the four-day survey recorded 15 lists, detecting 391 individuals. A total of 107 species from 40 families were identified, with a Shannon Diversity Index of H= 3.88 and Evenness EH= 0.65. Chao1 species richness, estimated via SuperDuplicates®, suggested approximately 138 species, with 31 undetected. The effective number of species (Numeff) was 48. Nine Bornean endemics were recorded, including the Borneo Ground Cuckoo. The survey also detected species of high conservation concern: the Helmeted Hornbill and the Greater Green Leafbird. Pycnonotidae was the most abundant family, with 45 individuals across 10 species. Insectivores dominated, with 167 individuals from 54 species and 20 families, followed by insectivores with 69 individuals from 15 species and eight families.