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Highly divergent regions in the complete plastome sequences of Aquilaria are suitable for DNA barcoding applications including identifying species origin of agarwood products

Hishamuddin MS, Lee SY, Syazwan SA, Ramlee SI, Lamasudin DU, Mohamed R

3 Biotech, 2023 Mar;13(3):78.
PMID: 36761338 DOI: 10.1007/s13205-023-03479-1

Members of Aquilaria Lam. (Thymelaeaceae) are evergreen trees that are widely distributed in the Indomalesia region. Aquilaria is highly prized for its unique scented resin, agarwood, which is often the subject of unlawful trade activities. Survival of the tree is heavily threatened by destructive harvesting and agarwood poaching, leading to its protection under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Unfortunately, an efficient species identification method, which is crucial to aid in the conservation efforts of Aquilaria is lacking. Here, we described our search for a suitable specific DNA barcode for Aquilaria species using eight complete plastome sequences. We identified five highly variable regions (HVR) (matK-rps16, ndhF-rpl32, psbJ-petA, trnD, and trnT-trnL) in the plastomes. These regions were further analyzed using the neighbor-joining (NJ) method to assess their ability at discriminating the eight species. Coupled with in silico primer design, two potential barcoding regions, psbJ-petA and trnT-trnL, were identified. Their strengths in species delimitation were evaluated individually and in combination, via DNA barcoding analysis. Our findings showed that the combined dataset, psbJ-petA + trnT-trnL, effectively resolved members of the genus Aquilaria by clustering all species into their respective clades. In addition, we demonstrated that the newly proposed DNA barcode was capable at identifying the species of origin of six commercial agarwood samples that were included as unknown samples. Such achievement offers a new technical advancement, useful in the combat against illicit agarwood trades and in assisting the conservation of these valuable species in natural populations.
SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-023-03479-1.
Fulltext Production of hydrogen using plastic waste via Aspen Hysys simulation

Yi CQ, Bojeng MNBHBH, Kamis SKBH, Mubarak NM, Karri RR, Azri H

Sci Rep, 2024 Feb 28;14(1):4934.
PMID: 38418697 DOI: 10.1038/s41598-024-55079-5

Plastic waste is being manufactured for the production of hydrogen. The amount of plastic waste collected annually is 189,953 tonnes from adjacent nations like Indonesia and Malaysia. Polyethylene (PE), Polypropylene (PP), Polyethylene Terephthalate (PET), Polyvinyl chloride (PVC), and Polystyrene (PS) are the five most prevalent forms of plastic found in most waste. Pyrolysis, water gas shift and steam reforming reaction, and pressure swing adsorption are the three main phases utilized and studied. In this research, authors examines the energy consumption on every stage. The plastic waste can be utilized to manufacture many hydrocarbons using the pyrolysis reaction. For this process, fast pyrolysis is being used at a temperature of 500 °C. A neutralization process is also needed due to the presence of Hydrochloric acid from the pyrolysis reaction, with the addition of sodium hydroxide. This is being carried to prevent any damage to the reactor during the process. Secondly, the steam reforming process continues after the water gas shift reaction has produced steam and carbon monoxide, followed by carbon dioxide and hydrogen formation. Lastly, pressure swing adsorption is designed to extract H2S and CO2 from the water gas shift and steam reforming reaction for greater purity of hydrogen. From the simulation study, it is observed that using various types of plastic waste procured (total input of 20,000 kg per hour of plastics) from, Brunei Darussalam, Malaysia and Indonesia, can produce about 340,000 tons of Hydrogen per year. Additionally, the annual profit of the Hydrogen production is estimated to be between $ 271,158,100 and $ 358,480,200. As per the economic analysis, it can be said that its a good to start hydrogen production plant in these regions.
Fulltext A renewable approach to electric vehicle charging through solar energy storage

Umair M, Hidayat NM, Sukri Ahmad A, Nik Ali NH, Mawardi MIM, Abdullah E

PLoS One, 2024;19(2):e0297376.
PMID: 38422065 DOI: 10.1371/journal.pone.0297376

Developing novel EV chargers is crucial for accelerating Electric Vehicle (EV) adoption, mitigating range anxiety, and fostering technological advancements that enhance charging efficiency and grid integration. These advancements address current challenges and contribute to a more sustainable and convenient future of electric mobility. This paper explores the performance dynamics of a solar-integrated charging system. It outlines a simulation study on harnessing solar energy as the primary Direct Current (DC) EV charging source. The approach incorporates an Energy Storage System (ESS) to address solar intermittencies and mitigate photovoltaic (PV) mismatch losses. Executed through MATLAB, the system integrates key components, including solar PV panels, the ESS, a DC charger, and an EV battery. The study finds that a change in solar irradiance from 400 W/m2 to 1000 W/m2 resulted in a substantial 47% increase in the output power of the solar PV system. Simultaneously, the ESS shows a 38% boost in output power under similar conditions, with the assessments conducted at a room temperature of 25°C. The results emphasize that optimal solar panel placement with higher irradiance levels is essential to leverage integrated solar energy EV chargers. The research also illuminates the positive correlation between elevated irradiance levels and the EV battery's State of Charge (SOC). This correlation underscores the efficiency gains achievable through enhanced solar power absorption, facilitating more effective and expedited EV charging.
Development of sperm cryopreservation protocol for patin buah, Pangasius nasutus

Idris N, Abduh MY, Mat Noordin N, Abol-Munafi AB, Koh ICC

Cryobiology, 2024 Feb 29.
PMID: 38431183 DOI: 10.1016/j.cryobiol.2024.104878

The development of sperm cryopreservation for Pangasius nasutus is necessary in order to serve the growing demand of this species through artificial fertilization and the preservation of valuable strains of male broodstocks. In the present study, the basic protocol of sperm cryopreservation for P. nasutus was established by identifying the optimal conditions for optimum cryoprotectant, toxicity of cryoprotectants, extenders, freezing condition and dilution ratio. Methanol (MeOH) at 10% concentration had the best post-thaw motility (26.3 ± 0.9%) and curvilinear velocity (VCL) compared to dimethyl acetamide and dimethyl sulfoxide. MeOH was the least toxic cryoprotectant; sperm suspended in 5 and 10% MeOH maintained motility up to 50 min. No significant differences were detected between the three types of extenders tested (0.9% sodium chloride, Calcium-free Hanks' Balance salt solution and ringer solution. P. nasutus sperm had a narrow range of optimal cooling rate. Significantly higher post-thaw motility was identified when cooling at 9.23 °C min-1, obtained by freezing at height of 14 cm above liquid nitrogen vapor for 7 min, showing lower cooling rate is suitable for this species. However, when cooling below and above the optimal cooling rate, post-thaw motility dropped drastically. There were no significant differences among the dilution ratios investigated, indicating the volume of cryodiluent at all tested ratios (1:9, 1:19 and 1:49) was sufficient for the protection of cells during the cryopreservation process. The development of the protocol for cryopreserved P. nasutus sperm will assist artificial seed production and provide an important tool for genetic and breeding research.
Unveiling the potential of membrane in climate change mitigation and environmental resilience in ecosystem

Ahmad T, Kumar N, Kumar A, Mubashir M, Bokhari A, Paswan BK, et al.

Environ Res, 2024 Mar 15;245:117960.
PMID: 38135098 DOI: 10.1016/j.envres.2023.117960

Carbon capture technologies are becoming increasingly crucial in addressing global climate change issues by lowering CO2 emissions from industrial and power generation activities. Post-combustion carbon capture, which uses membranes instead of adsorbents, has emerged as one of promising and environmentally friendly approaches among these technologies. The operation of membrane technology is based on the premise of selectively separating CO2 from flue gas emissions. This provides a number of different benefits, including improved energy efficiency and decreased costs of operation. Because of its adaptability to changing conditions and its low impact on the surrounding ecosystem, it is an appealing choice for a diverse array of uses. However, there are still issues to be resolved, such as those pertaining to establishing a high selectivity, membrane degradation, and the costs of the necessary materials. In this article, we evaluate and explore the prospective applications and roles of membrane technologies to control climate change by post-combustion carbon capturing. The primary proposition suggests that the utilization of membrane-based carbon capture has the potential to make a substantial impact in mitigating CO2 emissions originating from industrial and power production activities. This is due to its heightened ability to selectively absorb carbon, better efficiency in energy consumption, and its flexibility to various applications. The forthcoming challenges and potential associated with the application of membranes in post-carbon capture are also discussed.
Fulltext Geochemical dispersion of gold-bearing quartz veins in the Wadi Abu Khusheiba area in Southern Jordan

Mosleh M, Aziz JHA, Roselee MH, Al-Shorman A, Al Tamimi M, Alsoudi A

Geochem Trans, 2024 Mar 02;25(1):2.
PMID: 38429600 DOI: 10.1186/s12932-024-00085-9

This study delves into the geochemical dispersion of gold-bearing quartz veins in the Wadi Abu Khusheiba area, southern Jordan, with a focus on uncovering the complex patterns of mineralization and their geological significance. Employing an in-depth geochemical analysis of 24 rock samples from the region, we identified that these samples are predominantly hosted by oversaturated rhyolitic rocks, characterized by high SiO2 content and abundant free Quartz and orthoclase minerals. The mineralized zone of the quartz veins is particularly notable for its gold and silver concentrations, with maximum values reaching up to 5 ppm for gold and 18 ppm for silver. Our investigation into the elemental correlations revealed nuanced relationships, dependent on the 21 sample and analyzed at confidence level of (85%). Contrary to initial assumptions, we did not find a significant positive correlation between gold (Au) and arsenic (As), nor significant negative correlations between gold and other trace elements. These insights are critical for understanding the geochemical behavior of gold in the area and offer a nuanced view of elemental associations. The results of this study are significant for both academic research and practical exploration. They enhance our comprehension of the geological history and mineralization processes in Wadi Abu Khusheiba, providing valuable data that can inform future exploration strategies and deepen our understanding of mineral deposition in similar geological settings. This research not only contributes to the scientific community's knowledge of the area's geochemistry but also has potential implications for the mining and exploration industries.
Trypanosuppressive effects of Kolaviron may be associated with down regulation of Trypanothione reductase in Trypanosoma congolense infection

Timothy MR, Ibrahim YKE, Muhammad A, Chechet GD, Aimola IA, Mamman M

Trop Biomed, 2021 Mar 01;38(1):94-101.
PMID: 33797530 DOI: 10.47665/tb.38.1.016

Trypanothione reductase is a key enzyme that upholds the redox balance in hemoflagellate protozoan parasites such as T. congolense. This study aims at unraveling the potency of Kolaviron against trypanothione reductase in T. congolense infection using Chrysin as standard. The experiment was performed using three different approaches; in silico, in vitro and in vivo. Kolaviron and Chrysin were docked against trypanothione reductase, revealing binding energies (-9.3 and -9.0 kcal/mol) and Ki of 0.211μM and 0.151μM at the active site of trypanothione reductase as evident from the observed strong hydrophobic/hydrogen bond interactions. Parasitized blood was used for parasite isolation and trypanothione reductase activity assay using standard protocol. Real-time PCR (qPCR) assay was implored to monitor expression of trypanothione reductase using primers targeting the 177-bp repeat satellite DNA in T. congolense with SYBR Green to monitor product accumulation. Kolaviron showed IC50 values of 2.64μg/ml with % inhibition of 66.78 compared with Chrysin with IC50 values of 1.86μg/ml and % inhibition of 53.80. In vivo studies following the administration of these compounds orally after 7 days post inoculation resulted in % inhibition of Chrysin (57.67) and Kolaviron (46.90). Equally, Kolaviron relative to Chrysin down regulated the expression trypanothione reductase gene by 1.352 as compared to 3.530 of the infected group, in clear agreement with the earlier inhibition observed at the fine type level. Overall, the findings may have unraveled the Kolaviron potency against Trypanosoma congolense infection in rats.
Exploring use of a commercial passive sampler in a closed static chamber to measure ammonia volatilization

Sabrina J, Nurulhuda K, Amin AM, Sulaiman MF, Man HC

Environ Pollut, 2022 Dec 15;315:120282.
PMID: 36174812 DOI: 10.1016/j.envpol.2022.120282

Studies have indicated that up to 47% of total N fertilizer applied in flooded rice fields may be lost to the atmosphere through NH3 volatilization. The volatilized NH3 represents monetary loss and contributes to increase in formation of PM2.5 in the atmosphere, eutrophication in surface water, and degrades water and soil quality. The NH3 is also a precursor to N2O formation. Thus, it is important to monitor NH3 volatilization from fertilized and flooded rice fields. Commercially available samplers offer ease of transportation and installation, and thus, may be considered as NH3 absorbents for the static chamber method. Hence, the objective of this study is to investigate the use of a commercially available NH3 sampler/absorbent (i.e., Ogawa® passive sampler) for implementation in a static chamber. In this study, forty closed static chambers were used to study two factors (i.e., trapping methods, exposure duration) arranged in a Randomized Complete Block Design. The three trapping methods are standard boric acid solution, Ogawa® passive sampler with acid-coated pads and exposed coated pads without casing. The exposure durations are 1 and 4 h. Results suggest that different levels of absorbed NH3 was obtained for each of the trapping methods. Highest level of NH3 was trapped by the standard boric acid solution, followed by the exposed acid-coated pads without casing, and finally acid-coated pads with protective casing, given the same exposure duration. The differences in absorbed NH3 under same conditions does not warrant direct comparison across the different trapping methods. Any three trapping methods can be used for conducting studies to compare multi-treatments using the static chamber method, provided the same trapping method is applied for all chambers.
Fulltext Psychological capital research in HEIs: Bibliometric analysis of current and future trends

Zhang L, Wider W, Fauzi MA, Jiang L, Tanucan JCM, Naces Udang L

Heliyon, 2024 Feb 29;10(4):e26607.
PMID: 38404889 DOI: 10.1016/j.heliyon.2024.e26607

This study presents a comprehensive bibliometric analysis of the literature on psychological capital (PsyCap) within higher education institutions (HEIs). Its main objective is to offer an encompassing perspective on this field's current state and potential developments. To achieve this, the study examines present research trends and predicts future directions using a bibliometric approach. A total of 412 journal articles were gathered from the Web of Science database. The analysis identifies influential publications, outlines the knowledge structure, and forecasts future trends through bibliographic coupling and co-word analyses. The bibliographic coupling revealed five distinct clusters, while the co-word analysis identified four clusters. Despite the growing significance of PsyCap research in HEIs, there remains a need for greater academic efforts to comprehend the research landscape fully. This paper provides valuable insights into the expanding area of PsyCap research within HEIs. In conclusion, the study sheds light on the extensive research conducted on PsyCap in the context of HEIs and offers insights into its potential for further growth.
Fulltext Structural and functional insights into TRiC chaperonin from a psychrophilic yeast, Glaciozyma antarctica

Yusof NA, Kamaruddin S, Abu Bakar FD, Mahadi NM, Abdul Murad AM

Cell Stress Chaperones, 2019 Mar;24(2):351-368.
PMID: 30649671 DOI: 10.1007/s12192-019-00969-1

Studies on TCP1-1 ring complex (TRiC) chaperonin have shown its indispensable role in folding cytosolic proteins in eukaryotes. In a psychrophilic organism, extreme cold temperature creates a low-energy environment that potentially causes protein denaturation with loss of activity. We hypothesized that TRiC may undergo evolution in terms of its structural molecular adaptation in order to facilitate protein folding in low-energy environment. To test this hypothesis, we isolated G. antarctica TRiC (GaTRiC) and found that the expression of GaTRiC mRNA in G. antarctica was consistently expressed at all temperatures indicating their importance in cell regulation. Moreover, we showed GaTRiC has the ability of a chaperonin whereby denatured luciferase can be folded to the functional stage in its presence. Structurally, three categories of residue substitutions were found in α, β, and δ subunits: (i) bulky/polar side chains to alanine or valine, (ii) charged residues to alanine, and (iii) isoleucine to valine that would be expected to increase intramolecular flexibility within the GaTRiC. The residue substitutions observed in the built structures possibly affect the hydrophobic, hydrogen bonds, and ionic and aromatic interactions which lead to an increase in structural flexibility. Our structural and functional analysis explains some possible structural features which may contribute to cold adaptation of the psychrophilic TRiC folding chamber.
Fulltext Freshwater fishes (Actinopterygii) of Kenyir Reservoir, Peninsular Malaysia: Updated checklist, taxonomic concerns and alien species

Aqmal-Naser M, Ali NA, Azmi NU, Fahmi-Ahmad M, Rizal SA, Ahmad AB

Biodivers Data J, 2023;11:e100337.
PMID: 38327369 DOI: 10.3897/BDJ.11.e100337

BACKGROUND: A total of 87 freshwater fish species from 30 families were recorded from the Kenyir Reservoir, Peninsular Malaysia, where 75 are native and 12 are introduced species. Few species still have unstable taxonomy identities which urge further studies. Most of the species were categorised as Least Concern (LC) and two were threatened species; Endangered and Critically Endangered (EN and CR). One introduced species, Gambusiaaffinis is widespread in the human-associated area, while other introduced fish species can be considered low in numbers.
NEW INFORMATION: Twenty five fish species are recorded for the first time in the Kenyir Reservoir.
Fulltext Common but ignored: a new species of Cyrtodactylus (Chordata, Reptilia, Squamata, Gekkonidae) from lowland Sumatra Barat, Indonesia

Nugraha FAD, Ahda Y, Tjong DH, Kurniawan N, Riyanto A, Fauzi MA, et al.

Zookeys, 2023;1169:47-64.
PMID: 38328028 DOI: 10.3897/zookeys.1169.98681

The lowland region of Sumatra Barat has received little attention in previous biodiversity studies. Past studies have mainly focused on highland habitat and conservation areas. However, many populations of Cyrtodactylus in the lowland habitats of Sumatra Barat were not correctly identified. A phylogenetic tree based on the NADH dehydrogenase subunit 2 (ND2) gene showed that the lowland Sumatran population is the sister group of the Malaysian lowland species, C.semenanjungensis, together nesting within the agamensis group. The genetic divergence within the Sumatra Barat population is 0-4.2% and 18.3-20% to C.semenanjungensis. Further examination of morphological characters revealed that they differed from the sister clade and other Sumatran Cyrtodactylus members by a unique combination of characters such as absence of tubercle on brachium, presence of tubercle on ventrolateral fold, 32-41 paravertebral tubercles, 38-46 ventral scales, enlarged femoral scales, presence of precloacofemoral pores and 22-23 subdigital lamellae under fourth toe. Based on the morphological and molecular evidence, the lowland Sumatran population is herein described as a new species, increasing the number of species in Sumatra to seven. More comprehensive and intensive sampling efforts would most likely yield further discoveries in the group of Sumatran Cyrtodactylus in the near future.
Fulltext Ecofriendly Natural Surfactants in the Oil and Gas Industry: A Comprehensive Review

Abdurrahman M, Kamal MS, Ramadhan R, Daniati A, Arsad A, Abdul Rahman AF, et al.

ACS Omega, 2023 Nov 07;8(44):41004-41021.
PMID: 37970044 DOI: 10.1021/acsomega.3c04450

The use of different types of chemicals in upstream oilfield operations is critical for optimizing the different operations involved in hydrocarbon exploration and production. Surfactants are a type chemical that are applied in various upstream operations, such as drilling, fracturing, and enhanced oil recovery. However, due to their nonbiodegradability and toxicity, the use of synthetic surfactants has raised environmental concerns. Natural surfactants have emerged because of the hunt for sustainable and environmentally suitable substitutes. This Review discusses the role of natural surfactants in upstream operations as well as their benefits and drawbacks. The Review discusses the basic characteristics of surfactants, their classification, and the variables that affect their performance. Finally, the Review examines the possible applications of natural surfactants in the upstream oil sector and identifies areas that require further research.
Paediatric new onset type 1 diabetes and diabetic ketoacidosis during the COVID-19 pandemic in Malaysia

Lee YL, Nasir FFWA, Selveindran NM, Zaini AA, Lim PG, Jalaludin MY

Diabetes Res Clin Pract, 2023 Nov;205:110981.
PMID: 37890700 DOI: 10.1016/j.diabres.2023.110981

AIMS: Despite emerging evidence of increased paediatric diabetes mellitus (DM) and diabetic ketoacidosis (DKA) worldwide following the COVID-19 pandemic, studies in Asia are lacking. We aimed to determine the frequency, demographics, and clinical characteristics of new onset type 1 DM (T1DM) during the pandemic in Malaysia.
METHODS: This is a retrospective multicenter study involving new onset T1DM paediatric patients in Klang Valley, Malaysia during two time periods ie 18th September 2017-17th March 2020 (pre-pandemic) and 18th March 2020-17th September 2022 (pandemic).
RESULTS: There was a total of 180 patients with new onset T1DM during the 5-year study period (71 pre-pandemic, 109 pandemic). An increase in frequency of T1DM was observed during the pandemic (52 in 2021, 38 in 2020, 27 in 2019 and 30 in 2018). A significantly greater proportion of patients presented with DKA (79.8 % vs 64.8 %), especially severe DKA (46.8 % vs 28.2 %) during the pandemic. Serum glucose was significantly higher (28.2 mmol vs 25.9 mmol/L) with lower venous pH (7.10 vs 7.16), but HbA1c was unchanged.
CONCLUSIONS: New onset T1DM increased during the pandemic, with a greater proportion having severe DKA. Further studies are required to evaluate the mechanism leading to this rise to guide intervention measures.
Fulltext Exploring Patient Safety Culture: A Study of Community Pharmacies in Karachi, Pakistan

Khatri SA, Ahmad R, Osama M, Khan K, Khan MA, Ishaqui A, et al.

Cureus, 2024 Jan;16(1):e52135.
PMID: 38344495 DOI: 10.7759/cureus.52135

Background Community pharmacies are integral to the healthcare system, actively contributing to patient safety through accurate dispensing, education, collaboration, monitoring, and the implementation of safety protocols. Their accessibility and role as medication experts make them key partners in promoting positive health outcomes for individuals and communities. Objective The current study will evaluate the patient safety culture (PSC) among community pharmacies in Karachi, Pakistan. Additionally, this study will measure the association between patient safety culture in community pharmacies and the demographic characteristics of the pharmacy staff. Methods A cross-sectional survey of pharmacy staff was conducted using a survey instrument developed by the US Agency for Healthcare Research and Quality (AHRQ). Demographic variables and assessments of safety culture in pharmacies were studied. The data were analyzed using descriptive statistics. Results Among the 102 participants, positive responses ranged from 30% to 87.5%. The highest positive response was for the dimension "mistakes in communication" (86.3%), followed by "communication across shifts" (82.2%) and "communication openness" (81.7%). The dimensions "overall perceptions of patient safety" and "response to mistakes" had the lowest positive responses (56.0% and 60.9%, respectively). Furthermore, many staff did not regularly record the errors, even if they impacted the practices. Conclusion There was an overall unfavorable perception of patient safety culture among the surveyed pharmacies of Karachi, Pakistan. However, the communication dimensions showed the highest positive response. There is a strong need to improve the overall perception of patient safety among the staff and develop an optimistic response to mistakes.
Fulltext Nystagmus and Abducens Nerve Palsy as an Early Presentation of Non-alcoholic Wernicke Encephalopathy

Darussalam SH, Mohd Isa M, Md Saleh R, Mohmood A, Mohammad Razali A

Cureus, 2024 Jan;16(1):e52121.
PMID: 38344547 DOI: 10.7759/cureus.52121

Wernicke encephalopathy (WE) is a rare but life-threatening syndrome that is commonly associated with chronic alcoholism. It has also been found to be associated with malnutrition, prolonged parenteral nutrition, hemodialysis, hyperemesis gravidarum, gastroplasty, and AIDS. It usually presents as a clinical triad of confusion, ophthalmoplegia, and gait ataxia. Nystagmus is usually the most common and earliest ophthalmologic sign. We report a case of non-alcoholic WE in a patient who had prior bariatric surgery and was treated for malnutrition and sepsis, with nystagmus being the initial presentation. The MRI of the brain was normal. The diagnosis of WE was made clinically and was supported by the patient's symptomatic and clinical recovery following intravenous thiamine treatment. It is essential to highlight that a high level of suspicion is needed to diagnose non-alcoholic WE to allow the commencement of appropriate treatment and reduce morbidity and mortality rates related to this condition.
Phylogenetic Relationships of Sun Bear (Helarctos malayanus) Based on Mitochondrial DNA from Sumatra and Other Southeast Asian Regions

Roesma DI, Tjong DH, Syaifullah, Aidil DR, Maulana MR, Salis VM

Pak J Biol Sci, 2023 Nov;26(12):615-627.
PMID: 38334154 DOI: 10.3923/pjbs.2023.615.627

Background and Objective: The Helarctos malayanus is the sole bear species-living in Indonesia (Sumatra and Borneo). The available biological data for sun bears (H. malayanus) in Sumatra is limited, especially for morphological and genetic data. A morphological approach is difficult to do. Therefore, a molecular approach is the most likely choice. Phylogenetic analysis was carried out on H. malayanus in Central Sumatra (Dharmasraya, South Solok and Riau) using the Cytochrome B gene. Materials and Methods: Blood samples from three individuals of H. malayanus were obtained at the Sumatran Tiger Rehabilitation Center, Dharmasraya. Three H. malayanus Central Sumatra sequences and 62 GenBank sequences were used in the analysis. The DNA sequences were analyzed using the DNA Star, AliView, Bioedit, DNA SP, haplotype network, IQ Tree and MEGA software. Results: Forty-one haplotypes were identified in 65 sequences, with 17 haplotypes belonging to H. malayanus. Haplotype network analysis divides H. malayanus into Haplogroup I (Sundaland) and Haplogroup II (Mainland). All individuals of H. malayanus in Central Sumatra have the same haplotype as Peninsular Malaysia sequence. The sun bear (H. malayanus) has a monophyletic relationship with other bear species. The H. malayanus has a higher genetic distance between the two lineages (1.0-2.3%) than the genetic distance within the subpopulations of each lineage. Conclusion: The study results supported sun bear (H. malayanus) divided into two different lineages: Mainland (subcluster 1) and Sundaland (subcluster 2 and 3). The geographic isolation causes the absence of gene flow, which results in high genetic distance between sun bears (H. malayanus) in Sundaland and Mainland lineages.
Erythrocarpines IN, new limonoids from the barks of Chisocheton erythrocarpus and their neuroprotective effects against hydrogen peroxide in NG108-15 cells

Ngadni MA, Chong SL, Kamarudin MNA, Hazni H, Litaudon M, Supratman U, et al.

Fitoterapia, 2024 Mar;173:105765.
PMID: 38042506 DOI: 10.1016/j.fitote.2023.105765

A phytochemical study on the bark of Chisocheton erythrocarpus Hiern (Meliaceae) has led to the isolation of six new phragmalin-type limonoids named erythrocarpines I - N (1-6) along with one known limonoid, erythrocarpine F (7). Their structures were fully characterized by spectroscopic methods. The pre-treatment of NG108-15 cells with 1-5, 7 (2 h) demonstrated low to good protective effects against H2O2 exposure; 1 (83.77% ± 1.84 at 12.5 μM), 2 (69.07 ± 2.01 at 12.5 μM), 3 (80.38 ± 2.1 at 12.5 μM), 4 (62.33 ± 1.95 at 25 μM),5 (58.67 ± 1.85 at 50 μM) and 7 (66.07 ± 2.03 at 12.5 μM). Interestingly, 1 and 3 demonstrated comparable protective effects to positive control epigallocatechin gallate (EGCG) with similar cell viability capacity (≈ 80%), having achieved that at lower concentration (12.5 μM) than EGCG (50 μM). Collectively, the results suggested the promising use of 1 and 3 as potential neuroprotective agents against hydrogen peroxide-induced cytotoxicity in neuronal model.
Fulltext First Report of Colletotrichum scovillei Causing Anthracnose on Watermelon (Citrullus lanatus) in Malaysia

Goh KS, Balasubramaniam J, Sani SF, Alam MW, Ismail NA, Gleason ML, et al.

Plant Dis, 2022 Mar 06.
PMID: 35253485 DOI: 10.1094/PDIS-10-21-2211-PDN

Production of watermelon (Citrullus lanatus) in Malaysia was 150,000 mt in 2020 (Malaysian Department of Agriculture, 2021). In November 2019, nine locally produced watermelon fruit (red flesh, seedless) from five local stores in the states of Kelantan, Terengganu, and Penang exhibited sunken, circular, brown lesions that enlarged to1.5 to 10 cm in diameter with scattered orange masses of conidia. Lesions coalesced to cover approximately 50% of the fruit surface. Lesions were surface sterilized by spraying 70% alcohol onto the fruit followed by drying with sterilized paper towels. A total of 153 tissue segments (1×1 cm) were excised from the rind, immersed in 1% sodium hypochlorite for 3 min, rinsed twice for 1 min in sterilized distilled water, air-dried, transferred to potato dextrose agar (PDA) plates, and incubated at 25±1°C for 7 days. Single-spore transfers produced pure cultures, resulting in 12 isolates. Colonies on PDA were initially white and turned pale gray with age. Conidia were hyaline, one end round and the other narrowly acute, aseptate, smooth-walled, straight, cylindrical to clavate, 10.5-16.5 µm × 3-4.5 μm (n = 30). Observed morphological characters matched published description of Colletotrichum spp. (Damm et al. 2012). Internal transcribed spacer (ITS) and glyceraldehyde-phosphate dehydrogenase (GAPDH) genes were amplified using primer sets ITS1/ITS4 and GDF1/GDF2, respectively. All sequences were deposited in GenBank (MW856808 for ITS; MZ219296 for GAPDH). A BLASTn search of both sequences on GenBank showed 99% identity with C. scovillei along with other closely related Colletotrichum species. Phylogenetic analysis of ITS and GAPDH alignments, using maximum likelihood along with reference strains of closely related species from Mycobank, confirmed species identity as C. scovillei. A pathogenicity test was conducted on two healthy watermelon fruit (red flesh, seedless). A 6-mm-diameter mycelial plug of a colony on PDA was positioned on a 0.5-cm-long wound on each fruit; a sterile PDA plug placed on a similar wound on the opposite side served as a control. Fruit were incubated at 25±1°C for 7 days in plastic-wrapped trays above distilled water to maintain high humidity. Small, sunken, circular brown lesions appeared and expanded at inoculation sites within 7 days. Symptoms were identical to those produced by natural infections, and the controls were asymptomatic. Isolates from the lesions at the inoculation sites were confirmed as C. scovillei based on morphological characteristics, fulfilling Koch's postulates. The pathogenicity test was conducted four times with a total of eight fruit. Many species in the C. orbiculare complex cause watermelon anthracnose (Keinath, 2018). To our knowledge, this is the first report of C. scovillei (C. acutatum species complex; Damm et al. 2012) causing anthracnose on watermelon in Malaysia. Anthracnose caused by C. scovillei has been confirmed on other crops such as pepper (Toporek and Keinath, 2021), banana (Zhou et al., 2017), and chili (Oo et al., 2017). This insight will inform efforts to improve management of watermelon anthracnose in Malaysia.
Identification and mechanism determination of the efflux pump subunit amrB gene mutations linked to gentamicin susceptibility in clinical Burkholderia pseudomallei from Malaysian Borneo

Hussin A, Nathan S, Shahidan MA, Nor Rahim MY, Zainun MY, Khairuddin NAN, et al.

Mol Genet Genomics, 2024 Feb 21;299(1):12.
PMID: 38381232 DOI: 10.1007/s00438-024-02105-w

The bacterium Burkholderia pseudomallei is typically resistant to gentamicin but rare susceptible strains have been isolated in certain regions, such as Thailand and Sarawak, Malaysia. Recently, several amino acid substitutions have been reported in the amrB gene (a subunit of the amrAB-oprA efflux pump gene) that confer gentamicin susceptibility. However, information regarding the mechanism of the substitutions conferring the susceptibility is lacking. To understand the mechanism of amino acid substitution that confers susceptibility, this study identifies the corresponding mutations in clinical gentamicin-susceptible B. pseudomallei isolates from the Malaysian Borneo (n = 46; Sarawak: 5; Sabah: 41). Three phenotypically confirmed gentamicin-susceptible (GENs) strains from Sarawak, Malaysia, were screened for mutations in the amrB gene using gene sequences of gentamicin-resistant (GENr) strains (QEH 56, QEH 57, QEH20, and QEH26) and publicly available sequences (AF072887.1 and BX571965.1) as the comparator. The effect of missense mutations on the stability of the AmrB protein was determined by calculating the average energy change value (ΔΔG). Mutagenesis analysis identified a polymorphism-associated mutation, g.1056 T > G, a possible susceptible-associated in-frame deletion, Delta V412, and a previously confirmed susceptible-associated amino acid substitution, T368R, in each of the three GENs isolates. The contribution of Delta V412 needs further confirmation by experimental mutagenesis analysis. The mechanism by which T368R confers susceptibility, as elucidated by in silico mutagenesis analysis using AmrB-modeled protein structures, is proposed to be due to the location of T368R in a highly conserved region, rather than destabilization of the AmrB protein structure.

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