Malaysian Species Research Articles

Potential Utilisation of Solar-Assisted Kiln Dryer in Bamboo Drying

Bamboo is increasingly used as an alternative material for producing renewable and environmentally friendly products. Bamboo should be dried before use to increase its stability and improve its resistance against biodeterioration agents. The most common drying method for bamboo is through air-drying. Alternatively, artificial drying, such as solar drying, can produce optimum drying results regarding the drying rate and quality of bamboo throughput. This study investigated the potential utilisation of solar drying methods for processing local bamboo. The drying characteristics and physical and mechanical properties of solar-dried Gigantochloa levis bamboo culms’ bottom, middle, and top sections were determined. The drying time of G. levis culm has been reduced to about 40 days compared to the conventional air drying of 70 days using the solar-assisted kiln dryer. Solar-dried culms have a lower final moisture content of 20% than air-dried ones. The average circumference and diameter shrinkage values of solar-dried G. levis culms from green to approximately 12% moisture content were 3.22% and 4.29%, respectively, and the wall thickness shrinkage was 8.12%. The mean values of modulus of rupture and modulus of elasticity of solar-dried G. levis culm were 63.75 and 12567.99 N mm-2, respectively, while its mean values of compression and shear parallel to fibre were 45.87 and 10.01 N mm-2, respectively. The quality of solar-dried G. levis culms produced in this study showed the viability of using a solar-assisted kiln-dryer as a potential alternative processing method for drying local bamboo species in Malaysia.

Mitochondrial Genome of Endangered Hylobatidae, Hylobates agilis and Hylobates lar, of Peninsular Malaysia

Hylobates agilis and Hylobates lar, members of the family Hylobatidae, are classified as endangered species in Malaysia due to threats such as population decline and habitat loss. The aim of this study was to sequence and characterize the mitochondrial genome of H. lar and H. agilis. This study reported the total length of mitogenome of H. agilis and H. lar to be 16,473 and 15,949 base pair (bp), respectively. Each sequence contained 13 protein-coding sequences, 2 rRNAs, 22 tRNAs, and a control region D-loop (H. agilis); meanwhile for H. lar, there are 13 protein-coding sequences, 2 rRNAs, 19 trNAs, and a control region D-loop. Phylogenetic analysis showed both species formed a strong monophyletic clade within Hylobates grouping. Mitogenomic data of this study is essential for future references in evolutionary biology and conservation management of endangered Malaysian gibbons in captivity.

Novel Bioactive Peptides from Red Bigeye (Priacanthus macracanthus) Flesh Protein

Red bigeye (Priacanthus macracanthus) is a common fish species in Malaysia. This study reported an in silico assessment of the main proteins in red bigeye flesh as precursors for bioactive peptides. Six major proteins were chosen as precursors from the proteomic profiles of red bigeye proteins. Analyses using the BIOPEP-UWM database found that Protein number 4 gave the highest total number of bioactive peptides (5052 peptides), with dominant bioactivity in angiotensin-I-converting enzyme (ACE) inhibition (1571 peptides) and dipeptidyl peptidase-IV (DPP-IV) inhibition (2238 peptides). The ACE inhibitors had a frequency of bioactive fragment occurrences (A) of 0.4098, while the DPP-IV inhibitors gave a frequency of 0.5805. In silico proteolysis using BIOPEP-UWM found that pepsin (pH > 2) was the most promising proteinase in releasing a high number of DPP-IV and ACE inhibitory peptides. A novel peptide with significant potential was identified as QYKF. This study shows that red bigeye is a potential source of antihypertensive and antidiabetic peptides.

Machine Learning and Image Processing-Based System for Identifying Mushrooms Species in Malaysia

Malaysia, a country with a tropical climate characterized by consistent warmth and year-long high humidity, houses the perfect conditions for mushroom growth. Recently, there has been a surge in back-to-nature activities in Malaysia. However, many participants lack prior knowledge about the local flora and fungi, leading to a rise in mushroom poisoning cases, some of which have been fatal. Despite thorough research, there is a notable lack of identification studies specifically focused on mushroom species in Malaysia. Identifying these species is crucial for medical providers to effectively counteract the toxins from ingested mushrooms and also serves as an important educational tool. This study aims to determine the most suitable architecture for mushroom identification, focusing specifically on mushroom species found in Malaysia. A dataset of these mushrooms was curated, augmented, and processed through multiple variants of Vision Transformers (ViTs) and ResNet models, with uniform hyperparameters to ensure fairness. The results indicate that the ViT-L/16 model achieved the highest accuracy at 90.47%.

Extraction and characterization of morphological, physical, physiochemical, thermal, and chemical composition of five bamboo malaysian species

Extraction and characterization of morphological, physical, physiochemical, thermal, and chemical composition of five bamboo malaysian species

Cultivation of edible Caulerpa species in Malaysia: Current status and future prospects for sustainable aquaculture

Cultivation of edible Caulerpa species in Malaysia: Current status and future prospects for sustainable aquaculture

Physicochemical properties of Capsicum annum (red chilli) and Capsicum frutescens (bird’s eye chilli) seed powder

Capsicum annuum and Capsicum frutescens are the most widely cultivated species in Malaysia. Vegetable processing wastes, such as seeds, have been used as an alternative resource to manage waste and as a food source in the food industry. This research aimed to determine the potential of chilli seed powder as functional ingredient. Following this analysis, the proximate, phytic acid, and mineral were conducted for chemical analysis. Water and oil holding capacity and colour analysis were done for the physical study of chilli seed powder. Results showed that the crude fat, crude fibre, and protein contents were 22.24±0.50 g/100 g, 30.87±1.59 g/100 g and 17.57±0.28 g/100 g for C. annuum seed powder and 17.68±0.44 g/100 g, 24.07±1.57 g/100 g, 16.1±0.48 g/100 g for C. frutescens seed powder, respectively. Both chilli seed powders displayed low amounts of mineral contents, such as calcium (Ca), sodium (Na), magnesium (Mg) and zinc (Zn). In addition, C. frutescens seed powders exhibited phytic acid content (6.03±0.36 g/100 g) and red C. annuum seed powder (8.64±1.96 g/100 g). The low amount of phytic acid in both samples may be due to the low amount of minerals. The L* values of C. frutescens seed powder (68.21±0.35) were significantly higher than that of C. annuum seed powder (66.17±0.35), indicating the lightness in colour of both samples. As the L* value increased, the sample became lighter in colour. Positive a* and b* values led to a yellowish colour. The waterholding capacity (WHC) and oil-holding capacity (OHC) were 2.25±0.38 and 0.87±0.07, for C. annuum seed powder and 1.40±0.55 and 0.43±0.75 for C. frutescens seed powder, respectively. Both powders exhibited low averages of WHC and OHC due to the low amount of protein. Hence, C. annuum and C. frutescens seed powders may be used to improve colour for the development of food products.

Ethnoprimatology reveals new extended distribution of critically endangered banded langur Presbytis femoralis (Martin, 1838) in Pahang, Malaysia: Insights from indigenous traditional knowledge and molecular analysis.

The banded langur (Presbytis femoralis) is a critically endangered primate, which within Malaysia has not been known to extend significantly outside the state of Johor. Traditionally, distribution studies on this highly threatened primate have relied on conventional methods such as DNA identification, live counting, and camera trapping. However, ethnoprimatology offers an alternative approach to data collection, involving the active participation of indigenous and local communities possessing valuable knowledge and experience with local primate species. This study employed an integrated approach incorporating ethnoprimatology by utilizing pooled local expert opinion, local surveys, interviews, and fecal DNA analysis, resulting in a novel distribution range for the banded langur. The combination of expert opinions revealed this species' most optimistic distribution scenario across Johor and Pahang, inhabiting various ecosystems, including lowland forests, peat swamps, and human-modified landscapes. Further interviews and surveys conducted within the Orang Asli community in Tasik Chini and Tasek Bera have provided additional support for the revised distribution, documenting occurrences of banded langur utilization in indigenous practices, such as food consumption, cultural beliefs, medicinal applications, and craftsmanship. Phylogenetic analysis demonstrated genetic differentiation between populations in Johor and Pahang, with the populations in the southern part of Peninsular Malaysia likely serving as ancestral sources for other populations. Consequently, this study not only elucidated the updated distribution of banded langur through DNA records and direct observations but also established the efficacy of ethnoprimatology as a precursory tool for uncovering the present distribution patterns of other primate species in Malaysia.

Aquaponics Vs. Recirculating Aquaculture System: Assessing Productivity and Water Use Efficiency of Native Fish Species Empurau (Tor tambroides) and Jelawat (Leptobarbus hoevenii) Compared to Red Hybrid Tilapia

A 3 × 2 (fish species × culture system) factorial design experiment was conducted to compare productivity of empurau (Tor tambroides), jelawat (Leptobarbus hoevenii) and red hybrid tilapia (Oreochromis sp., control) cultured in recirculating aquaculture system (RAS) and aquaponics system. Growth performance, feed conversion ratio (FCR) and survival rate of fish were evaluated, and water quality of all tanks throughout the 70-days experiment was determined. In the present study, FCR of tilapia, empurau and jelawat tended to be lower in aquaponics than RAS, while no significant differences (P>0.05) on weight gain (WG) and specific growth rate (SGR) between RAS and aquaponics for each fish species were observed. Although tilapia had significantly higher WG and SGR, and lower FCR compare to empurau and jelawat, the survival rate of empurau and jelawat were higher than tilapia, regardless of the culture system. Between empurau and jelawat, better growth performance was observed in aquaponics than in RAS. Significantly higher (p<0.05) ammonia and nitrite concentrations were shown in RAS tanks as compared to aquaponics tanks, regardless of the fish species. Jelawat might have wide range tolerance to ammonia as no mortality in both RAS and aquaponics, while tilapia and empurau had higher survival rate in aquaponics than RAS. In summary, aquaponics appears to be a viable approach to enrich variety and improve fish production in an environmentally responsible manner. Therefore, it is plausible to advocate for the use of aquaponics as a sustainable methods of farming native fish species in Malaysia.

Vanishing giants: An assessment on the population status of giant clams across Malaysia

The iconic giant clams are known for its multifaceted importance throughout the Indo-Pacific –for functional, ecological, or cultural purposes. In Malaysia, habitat destruction and illegal poaching were main reasons behind the declining populations of giant clams. As previous surveys date back to 1990 s, an update on the status of giant clam populations in Malaysia is overdue. Using the extensive monitoring data from Reef Check Malaysia, we analysed and provided an assessment of population trends of giant clams between 2007 and 2021 in Malaysia. This study showed a decline in giant clam population in the east coast Peninsula and Sabah, while their abundances have always been low in the west coast Peninsula and Sarawak. In the east coast Peninsula, Tridacna maxima and T. crocea were most common (2.7 ± 7.3 and 1.4 ± 7.6 clams per 100 m2, respectively), followed by T. squamosa (0.7 ± 1.4 clams per 100 m2), and Hippopus hippopus (0.3 ± 2.5 clams per 100 m2). The boring species, T. maxima and T. crocea, typically displayed highly aggregated populations, reaching densities of 41.5 and 70 clams per 100 m2, where a reciprocal abundance shift between both species was observed between northern and southern sites of east coast Peninsula. The demography of T. maxima and T. crocea is either positively skewed or normally distributed, indicating abundant recruits that correspond to their higher densities. In contrast, T. squamosa showed a negative skew, suggesting poor recruitment rates. Findings here underscore the need to tailor conservation strategies for respective giant clam species in Malaysia. Proposed initiatives include establishing conservation zones in key areas like Perhentian, Lang Tengah, Redang, and Tioman Islands, which have significant T. maxima and T. crocea recruit populations. Also, targeted restocking efforts are necessary for T. squamosa and H. hippopus to ensure long-term viability of populations.

Reproductive Biology and Spawning Pattern of Oyster Magallana bilineata in Mengkabong Bay, Sabah, Malaysia

Abstract Magallana bilineata is a commercially important oyster species in Malaysia. Despite its economic significance, the biology and ecology of this species, particularly its reproductive cycle, are poorly understood in the region. Therefore, this study aimed to investigate the reproductive cycle of M. bilineata in Mengkabong Bay, Tuaran, Sabah and its correlation with environmental factors. A total of 105 oyster specimens were collected and examined to determine the sex ratio, gonad developmental stages, maturity index (MI), and condition index (CI). The results revealed a sex ratio of 1:2.36 (♂:♀) in the oyster population of the bay, with a significantly higher proportion of females (P < 0.05). Hermaphroditism was detected in 1.90% of the samples. M. bilineata was found to spawn throughout most months in the bay, with the highest MI and CI values recorded in November 2019 when most oysters were in mature or maturing stages. Salinity was found to be the primary factor influencing male gonad maturation, while temperature was the primary factor influencing female gonad maturation. Understanding the reproductive biology of this species is crucial for predicting its future survival and facilitating assisted spawning and hatchery spat production, thereby ensuring the conservation and sustainability of the oyster fishery in Malaysia.

Five-year species distribution and antimicrobial susceptibility of non-tuberculous mycobacteria in Malaysia, 2018-2022.

Introduction. Non-tuberculous Mycobacteria (NTM) is a group of mycobacteria distinct from the Mycobacterium tuberculosis complex. They can cause opportunistic infections, especially in immunocompromised individuals.Gap Statement. Over the last few years, there has been a growing concern regarding the distribution and antimicrobial resistance of NTM in Malaysia. however, a comprehensive study to fully grasp the NTM situation has yet to be conducted.Aim. This study aimed to investigate the species distribution and antimicrobial susceptibility patterns of NTM isolated from clinical samples in Malaysia from 2018 to 2022.Methodology. A retrospective analysis was conducted on NTM isolates obtained from various clinical specimens over a span of five years. The isolates were identified using phenotypic and molecular techniques, and antimicrobial susceptibility profiles for clinically significant isolates were determined using minimum inhibitory concentration.Results. The study revealed a diverse distribution of NTM species in Malaysia, with Mycobacteroides abscessus complex and Mycobacterium avium complex emerging as the most predominant. Furthermore, the antimicrobial susceptibility patterns showed varying degrees of resistance to commonly used antibiotics, highlighting the significance of treatment tailored to susceptibility testing results.Conclusion. This study provides valuable perspective into the epidemiology of NTM in Malaysia. The information gained from this study should prove useful for empirically treating serious NTM infections prior to species identification and the availability of antimicrobial susceptibility testing results.

First record of Caligusdussumieri Rangnekar, 1957 (Copepoda, Siphonostomatoida, Caligidae) from Malaysia, with notes on caligids found from Malaysia and on host-specificity of caligids on lutjanid fishes.

In total, 14 species of Caligus have been reported from Malaysia. Amongst them, four species are reported from lutjanid fishes. Caligusdussumieri Rangnekar, 1957 is reported from Malabar snapper, Lutjanusmalabaricus, purchased from a local wet market in Terengganu, Peninsular Malaysia. This is the first record of this species in Malaysia and it is only the second species assigned to the bonito-group of the genus Caligus to be reported from Malaysia. A key to species of the bonito-group is presented herein. The list of caligids infecting lutjanid fishes and the geographical distributions plus the known hosts of members of the bonito-group of Caligus are discussed.

Analysis of Pyrrolizidine Alkaloids in Stingless Bee Honey and Identification of a Botanical Source as Ageratum conyzoides.

Stingless bee honeys (SBHs) from Australian and Malaysian species were analysed using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for the presence of pyrrolizidine alkaloids (PAs) and the corresponding N-oxides (PANOs) due to the potential for such hepatotoxic alkaloids to contaminate honey as a result of bees foraging on plants containing these alkaloids. Low levels of alkaloids were found in these SBHs when assessed against certified PA standards in targeted analysis. However, certain isomers were identified using untargeted analysis in a subset of honeys of Heterotrigona itama which resulted in the identification of a PA weed species (Ageratum conyzoides) near the hives. The evaluation of this weed provided a PA profile matching that of the SBH of H. itama produced nearby, and included supinine, supinine N-oxide (or isomers) and acetylated derivatives. These PAs lacking a hydroxyl group at C7 are thought to be less hepatoxic. However, high levels were also observed in SBH (and in A. conyzoides) of a potentially more toxic diester PA corresponding to an echimidine isomer. Intermedine, the C7 hydroxy equivalent of supinine, was also observed. Species differences in nectar collection were evident as the same alkaloids were not identified in SBH of G. thoracica from the same location. This study highlights that not all PAs and PANOs are identified using available standards in targeted analyses and confirms the need for producers of all types of honey to be aware of nearby potential PA sources, particularly weeds.

PRELIMINARY STUDY OF THE POLLEN MORPHOLOGY OF MALAYSIAN ZINGIBERACEAE (TRIBE ALPINIEAE) AND THE TAXONOMIC RELATIONSHIP

The family Zingiberaceae forms an important herbaceous layer in the tropical forests of Malaysia. From a phylogenetic point of view, certain genera of the problematic tribe Alpinieae are non-monophyletic and in need of more taxonomic evidence to support the classification. This study demonstrates how the palynological data could correlate with the proposed phylogenetic data, using representatives from the Malaysian species. The pollen morphology of 21 species from the tribe Alpinieae was investigated. Parameters including polarity, symmetry, shape, size, apertures, exine ornamentation, size of spine, type of spine apex, spine density, and distance between spine were analysed. The results demonstrated that the studied species were conveniently divided into two major groups based on the exine sculpturing of the spheroidal pollens, either psilate as in Etlingera and Hornstedtia, or echinate as in Alpinia, Conamomum, Meistera, Plagiostachys, Sundamomum, and Sulettaria. Hence, as far as the study is concerned, the main sculpturing is considered useful to generally distinguish the genera in the tribe.

Taxonomic Significance of Leaf Micromorphology in Selected Garcinia from Peninsular Malaysia

Garcinia is a notably large genus from Clusiaceae. This genus is approximately discovered across Asia and Africa, predominantly in Southeast Asia. The recent taxonomic revision revealed several changes in the species classification within the Garcinia taxa. Additionally, few data on the anatomical characteristics of Garcinia species in Malaysia have been documented recently. This study aims to identify the leaf micromorphological characters using scanning electron microscopy (SEM) on Garcinia mangostana var. mangostana, G. mangostana var. malaccensis and G. celebica in Peninsular Malaysia. The result of this study found several important characteristics in terms of stomatal size, stomatal shape as well as abaxial and adaxial cuticular sculpturing. In conclusion, this study proposed that the anatomical characteristics in these selected Garcinia species might have a significant taxonomic value that can be applied to species identification and classification. Keywords: Garcinia, Garcinia celebica, Garcinia mangostana var. malaccensis, Garcinia mangostana var. mangostana, leaf micromorphology

DNA barcodes and species boundaries of black flies (Diptera: Simuliidae) in Malaysia

Black flies play a prominent role in public health and the epidemiology of parasitic diseases of humans, domesticated and wild animals. Correct identification and a comprehensive survey are required to identify vector and pest species and thus understand their biological attributes which play a vital role in the monitoring program. DNA barcoding is an established molecular tool that provides rapid and accurate species identification. Our study strengthens the molecular database for black flies in Malaysia by adding 59 cytochrome c oxidase I sequences for 22 species, of which 14 are included for the first time. These sequences, combined with those in public databases, represent a total of 338 sequences for 52 Malaysian species, nearly 50% of which were collected from type localities. At the subgeneric level, barcode gap analysis most accurately identified species in the subgenus Nevermannia (92%), followed by Simulium s. l. (91%), and Gomphostilbia (81%). The remaining sequences were ambiguous and could not be distinguished from those of nearest neighbour species due to an overlap in genetic divergence and low genetic diversity, especially between insular species. Tree analyses indicate that certain species had incomplete lineage sorting and low mitochondrial signals. Possible cryptic species were indicated in the Simulium (Gomphostilbia) batoense and S. (G.) epistum species groups. Species delimitations were consistent with morphological identifications except in large species groups such as the S. (G.) asakoae, S. (G.) batoense, S. (G.) epistum, and S. (Simulium) melanopus groups. The use of type specimens or specimens collected from type localities (topotypes) in barcoding is strongly recommended for reference sequences to increase the reliability of the molecular database.

ICP ANALYSIS OF HEAVY METALS IN MERETRIX SPP. FROM PANTAI SEPAT, KUANTAN, PAHANG

Hard clams constitute the genus Meretrix is one of the most demanded bivalvia species in Malaysia. However, the unknown level of heavy metal content raises concerns for the health of seafood lovers, particularly those who consume seafood from Pantai Sepat, Kuantan, Pahang. Using bivalves as bio-indicators, the objectives of this study are to determine the level of concentration of Copper (Cu), Zinc (Zn), Cadmium (Cd) and Lead (Pb), and to evaluate these concentrations according to the permissible limits established by the Malaysia Food Act (1983) and Food Regulations (1985) and the World Health Organisation (1982). Before analysing the samples with Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), the collected and desiccated samples were digested with acid. The concentrations of copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) were determined to be 0.56 ppm, 6.76 ppm, 0.06 ppm, and 0.04 ppm, respectively. The order of metals in the collected Meretrix spp. is Zn> Cu> Cd> Pb. The concentrations of all elements present in the hard clams were assessed and found to fall within acceptable thresholds, indicating that they are suitable for consumption without posing any health risks. Keyword(s) : heavy metal; Meretrix genus; Pantai Sepat, Pahang

WILD BANANA PLANTS AND THEIR MANAGEMENT IN OIL PALM PLANTATIONS

Several species of wild banana plants can be encountered in oil palm plantations and a number of them are considered as weeds. Some wild banana species in Malaysia are Musa acuminata, Musa violascens, Musa gracilis, Musa balbisiana, Musa beccari, Musa campestris, Musa monticola, Musa borneensis, Musa ornata and Musa juwiniana. These wild banana plants produce inedible fruits with many large hard seeds. Musa ornata, M. violascens and M. gracilis are cultivated as ornamentals in gardens because of their unique appearance with brightly coloured bracts and other colourful parts in red, purple, pink, or white. This paper gives a brief account of these wild banana species and deliberate in general the classification, names, distribution, habitats, plant features, pollination, dispersal, and uses. The most common wild banana weed encountered in oil palm plantations is M. acuminata. The weed status and management aspects of the wild banana weeds are deliberated and focussed on and to a lesser extent references to the control of unwanted banana plants/disease infected plants are also given. The early detection and control of wild banana weeds are the strategies adopted for the management of these weeds in oil palm plantations. In the integrated weed management approach, preventive measures are preferred. When planters encounter serious infestation of these weeds, several control measures of applying herbicides (2,4-D herbicides, glyphosate isopropylamine, metsulfuron-methyl) such as trunk injection, insertion of treated sticks and cut and application are possible. In the writer’s opinion, cutting and applying a few drops of 2,4-D herbicide concentrate is probably the obvious recommendation for controlling wild banana weeds in serious widespread infestation in replanting fields and immature planting in oil palm plantations. Keywords: Wild banana plants, Musa species, weeds, ornamental, oil palm, management, herbicides.

A synopsis of the genus Lepidagathis (Acanthaceae) in India, new taxa and notes on Dalzell's species

Nicolas Alexander Dalzell (1817–1878) described seven species of Lepidagathis (Acanthaceae). Except for Lepidagathis grandiflora, which was later recognized as Calacanthus, all are retained in the genus Lepidagathis. Of these, five are endemic to peninsular India. While exploring Dalzell’s species, we have made field explorations, consulted Lepidagathis collection at different herbaria, and presented here a synopsis of the genus in India. The nomenclature, taxonomy, distribution, and The International Union for Conservation of Nature (IUCN) threat status of Lepidagathis species in India are reviewed. Nomenclature and taxonomic notes on L. cristata and L. cuspidata and the infraspecific taxa in L. pungens, L. incurva are provided. Lepidagathis aristata, a Malaysian species is resurrected; a new name Lepidagathis forskaolii is proposed for the oldest basionym Ruellia aristata. Lepidagathis clavata, L. prostrata, and L. rigida are rare, and only known by a few collections, L. lutea is confined to Konkan and adjoining areas. Lepidagathis cuspidata is collected from its entire geographic range and an overlooked variety, L. cuspidata var. stenostegia is resurrected. Based on live and herbarium collections, a riverine, elliptic-linear-leaved variety elliptica is proposed. Lepidagathis dalzellii, a large flowered new species, allied to L. cuspidata from the United Nations Educational, Scientific and Cultural Organization (UNESCO) World Natural Heritage Site (Kaas plateau, Maharashtra) is also described and illustrated.