Kaempferia parviflora is an ethnomedicinally important plant. Conventional propagation of K. parviflora is hindered by slow growth rate, long dormancy periods and dual use of rhizomes for seeds as well as marketable produce. In our study, we developed a promising dual-phase micropropagation protocol to increase number of plantlets, survivability, biomass and quality plantlets for mass production. Multiple shoot regeneration was found most successful on Murashige and Skoog (MS) media supplemented with 35.52 μM N6-benzyladenine (BA) in terms of highest number of shoots (22.4 ± 1.84), leaves (29.27 ± 1.30), and roots (17.8 ± 1.72) per explant. High survivability was observed with an acclimatisation percentage of 100% in sterile perlite medium. This method was shown to be preferable compared to conventional propagation in terms of propagation time and number of plantlets. Regenerated in vitro plantlets were then successfully induced to form microrhizomes in MS media with an optimal concentration of 6% (w/v) sucrose. Increase in microrhizome biomass (35.7 ± 2.59 g per flask), number of microrhizomes (5.2 ± 0.78), shoots (8.5 ± 1.58) and roots (8.5 ± 1.58) were observed for this treatment. This investigation successfully highlights the manipulation of single factors in short time frame to produce a simple and efficient alternative propagation method for K. parviflora.
A total of 33 isolates of Fusarium sp. were isolated from soil samples collected from a mangrove forest in an area in Kampung Pantai Acheh, Balik Pulau, Pulau Pinang, Malaysia. The isolates were isolated using soil dilution, direct isolation and debris isolation techniques. The debris isolation technique yielded the most isolates, with a total of 22 Fusarium isolates. Based on identification using morphological characteristics, three Fusarium species were identified: F. solani, F. oxysporum and F. verticillioides. F. solani (91%) was the most common species recovered from the mangrove soil samples, followed by F. oxysporum (6%) and F. verticillioides (3%).
Endophytic fungi inhabit apparently healthy plant tissues and are prevalent in
terrestrial plants, especially root tissues, which harbour a wide assemblage of fungal
endophytes. Therefore, this study focused on the isolation and characterisation of
endophytic fungi from the roots of wild banana (Musa acuminata). A total of 31 isolates of
endophytic fungi were isolated from 80 root fragments. The endophytic fungi were initially
sorted according to morphological characteristics and identified using the sequences of
the translation elongation factor-1α (TEF-1α) gene of Fusarium spp. and the Internal
Transcribed Spacer (ITS) regions of other fungi. The most common fungal isolates were
species of the genus Fusarium, which were identified as F. proliferatum, Fusarium sp.,
F. solani species complex, and F. oxysporum. Other isolated endophytic fungi included
Curvularia lunata, Trichoderma atroviride, Calonectria gracilis, Rhizoctonia solani,
Bionectria ochroleuca, and Stromatoneurospora phoenix (Xylariceae). Several of the
fungal genera, such as Fusarium, Trichoderma, Rhizoctonia, and Xylariceae, are among
the common fungal endophytes reported in plants. This study showed that the roots of wild
banana harbour a diverse group of endophytic fungi.
Mating studies were conducted on 78 isolates of Fusarium species section Liseola from rice, sugarcane and maize. From the crosses with tester strains of Gibberella fujikuroi species complex, 64.1% (50 out of 78 isolates) were cross-fertile with tester strains of mating populations A to E. The results of the mating studies showed that of the 50 isolates, 19 belonged to mating population A (Gibberella moniliformis), 18 to mating population B (Gibberella sacchari), 4 to mating population E (Gibberella subglutinans), 6 to mating population D (Gibberella intermedia) and 3 to mating population C (G. fujikuroi). Identification of several mating populations from rice,sugarcane and maize could be important biological entities under field conditions.
Species of the genus Chattonella (Raphidophyceae) are a group of marine protists that are commonly found in coastal waters. Some are known as harmful microalgae that form noxious blooms and cause massive fish mortality in finfish aquaculture. In Malaysia, blooms of Chattonella have been recorded since the 1980s in the Johor Strait. In this study, two strains of Chattonella were established from the strait, and morphological examination revealed characteristics resembling Chattonella subsalsa. The molecular characterization further confirmed the species' identity as C. subsalsa. To precisely detect the cells of C. subsalsa in the environment, a whole-cell fluorescence in-situ hybridisation (FISH) assay was developed. The species-specific oligonucleotide probes were designed in silico based on the nucleotide sequences of the large subunit (LSU) and internal transcribed spacer 2 (ITS2) of the ribosomal DNA (rDNA). The best candidate signature regions in the LSU-rRNA and ITS2-rDNA were selected based on hybridisation efficiency and probe parameters. The probes were synthesised as biotinylated probes and tested by tyramide signal amplification with FISH (FISH-TSA). The results showed the specificity of the probes toward the target cells. FISH-TSA has been proven to be a potential tool in the detection of harmful algae in the environment and could be applied to the harmful algal monitoring program.
Indonesia is home to several tree taxa that are harvested for agarwood. This highly valuable oleoresin ironically was the cause for some species to become vulnerable due to gluttonous human activity. However, information on the genetic diversity of these endangered trees is limited. In this study, 28 specimens representing eight species from two genera, Aquilaria and Gyrinops, were collected from ex-situ and in-situ populations in Indonesia. Phylogenetic analysis conducted on DNA sequences of the nuclear ribosomal internal transcribed spacer (ITS) and the trnL-trnF intergenic spacer regions, revealed that Aquilaria and Gyrinops are paraphyletic when Aquilaria cumingiana is excluded. The phylogenetic analysis for ITS and trnL-trnF showed capability to categorise agarwood-producing species based on their regions: East Indonesia and West Indonesia, using Wallace's Line as the divider. In addition, we discuss challenges in species identification and taxonomy of agarwood-producing genera, and their conservation efforts in Indonesia.
Stevia rebaudiana, a perennial herb native to northeastern Paraguay, has gained immense attention globally over the recent decades due to the natural sweetness of its leaves. Like in most plants, this particular species contains high amount of secondary metabolites, thus rendering the isolation of high quality and quantity RNA extract for molecular applications rather challenging. An effective, high-yield and high-quality RNA isolation protocol for this economically important plant species was devised here based on the cetyltrimethylammonium bromide (CTAB) extraction method, with an additional genomic DNA (gDNA) removal step. DNA and other contaminants that may affect downstream applications were effectively removed. Our results exhibited that RNA samples isolated from the leaves and stems of Stevia rebaudiana using this improvised method are high in integrity and quality with RNA integrity number (RIN) of more than 8 and low in contaminants.
The yellow tetrazolium salt 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) is widely used to determine cell viability in cell proliferation and cytotoxic assays. MTT is reduced by metabolically active cells to form an insoluble purple formazan product that is quantifiable by spectrophotometry. It is the most common and direct assay for cell viability. However, in this present study, we demonstrated that the vitamin E isomers α-β-γ-δ-tocotrienols and α-tocopherol were able to reduce MTT into a formazan product, despite the absence of living cells. For comparison, a second method for determining cell viability, which is the neutral red uptake assay, was used in parallel with the MTT assay. The results showed that neutral red did not interact with the vitamin E isomers. Our findings suggest that the MTT assay is not suitable for studying the proliferative effects of vitamin E isomers on cell growth.
Fig, or Ficus carica, is a fruit tree from the Moraceae family and is widely grown in tropical and subtropical regions of the world. Fig plants are mainly propagated through grafting, air layering, and hardwood cutting whereby these methods were found to be less efficient. Plant tissue culture is efficient method to propagate plants, particularly to produce true-to-type platelets for mass multiplication. The aim of this study is to induce multiple shoot formation on Ficus carica cv. Japanese BTM 6 through identifying and optimising the concentrations of 6-Benzylaminopurine (BAP) and Zeatin suited for shoot formation. The axillary shoot tip explants were cultured in MS media supplemented with different concentrations of BAP and Zeatin (0, 0.5, 1.0, 1.5 and 2.0 mg/L) to determine the optimal concentration for the formation of multiple shoots. Number of shoots per explants and the differences in shoot height of explants were calculated after 8 and 12 weeks of culture respectively. Of all the treatments of BAP, MS media containing with 2 mg/L BAP marked the highest number of shoots per explant with the average value of 1.67 ± 0.33 while 1.5 and 2 mg/L of BAP produced the highest differences in shoot height with 0.51 ± 0.08 cm and 0.51 ± 0.07 cm after 12 weeks respectively. Murashige and Skoog (MS) media supplemented with 2 mg/L Zeatin showed the highest production of multiple shoots and differences in shoot height with the average of 0.83 ± 0.219 and 0.32 ± 0.04 cm respectively among all the different treatments of Zeatin. In this study, BAP performed better in shoot induction and elongation as compared to Zeatin for the cultivar Japanese BTM 6.
The metabolism of alcohol involves cytochrome P450 2E1 (CYP2E1)-induced oxidative stress, with the association of phosphatidylinositol-3-kinases (PI3K) and nuclear factor kappa B (NFκB) signalling pathways. CYP2E1 is primarily involved in the microsomal ethanol oxidising system, which generates massive reactive oxygen species (ROS) and ultimately leads to oxidative stress and tissue damage. Lauric acid, a major fatty acid in palm kernel oil, has been shown as a potential antioxidant. Here, we aimed to evaluate the use of lauric acid as a potential antioxidant against ethanol-mediated oxidative stress by investigating its effect on CYP2E1 mRNA expression and the signalling pathway in ethanol-induced HepG2 cells. HepG2 cells were firstly treated with different concentrations of ethanol, and subsequently co-treated with different concentrations of lauric acid for 24 h. Total cellular RNA and total protein were extracted, and qPCR and Western blot was carried out. Ethanol induced the mRNA expression of CYP2E1 significantly, but lauric acid was able to downregulate the induced CYP2E1 expression in a dose-dependent manner. Similarly, Western blot analysis and densitometry analysis showed that the phosphorylated PI3K p85 (Tyr458) protein was significantly elevated in ethanol-treated HepG2 cells, but co-treatment with lauric acid repressed the activation of PI3K. However, there was no significant difference in NFκB pathway, in which the normalised NFκB p105 (Ser933) phosphorylation remained constant in any treatment conditions in this study. This suggests that ethanol induced CYP2E1 expression by activating PI3K p85 (Tyr458) pathway, but not the NFκB p105 (Ser933) pathway in HepG2 cells.
Burkholderia pseudomallei is a soil-dwelling bacterium that causes a globally emerging disease called melioidosis. Approximately one third of the in silico annotated genes in its genome are classified as hypothetical genes. This group of genes is difficult to be functionally characterised partly due to the absence of noticeable phenotypes under conventional laboratory settings. A bioinformatic survey of hypothetical genes revealed a gene designated as BPSL3393 that putatively encodes a small protein of 11 kDA with a CoA binding domain. BPSL3393 is conserved in all the B. pseudomallei genomes as well as various in other species within the genus Burkholderia. Taking into consideration that CoA plays a ubiquitous metabolic role in all life forms, characterisation of BPSL3393 may uncover a previously over-looked metabolic feature of B. pseudomallei. The gene was deleted from the genome using a double homologous recombination approach yielding a null mutant. The BPSL3393 mutant showed no difference in growth rate with the wild type under rich and minimal growth conditions. An extensive metabolic phenotyping test was performed involving 95 metabolic substrates. The deletion mutant of BPSL3393 was severely impaired in its ethanolamine metabolism. The growth rate of the mutant was attenuated when ethanolamine was used as the sole carbon source. A transcriptional analysis of the ethanolamine metabolism genes showed that they were down-regulated in the BPSL3393 mutant. This seemed to suggest that BPSL3393 functions as a positive regulator for ethanolamine metabolism.
Keradangan hati berkait rapat dengan perubahan dalam ekspresi lipoprotein dan apolipoprotein. Interferon-γ (IFN-γ), wakil tunggal jenis kedua IFN, memainkan peranan yang penting dalam memodulasi dan mempergiatkan tindak balas keradangan. Justeru itu, kajian ini direka untuk mengenal pasti kesan IFN-γ terhadap apolipoprotein A-I (APOA-I) dan penglibatan nuclear factor–kappa B (NF-κB) dalam laluan isyarat tersebut. Tindak balas rantai polymerase transkripsi berbalik kuantitatif (qRT-PCR) dan analisis blot western telah dilaksanakan untuk menguantifikasi ekspresi APOA-I dalam sel-sel HepG2 selepas dirawat dengan IFN-γ. Kajian ini menunjukkan bahawa 50 ng/mL IFN-γ merangsangkan ekspresi mRNA dan protein APOA-I. Walau bagaimanapun, pra-rawatan sel dengan inhibitor laluan isyarat NF-κB mengurangkan tahap ekspresi APOA-I. Kajian ini juga mendemonstrasikan penglibatan langsung isyarat NF-κB dalam ekspresi APOA-I akibat rangsangan IFN-γ, di mana IFN-γ meningkatkan tahap fosforilasi NF-κB p65 Ser468 dan Ser536 kepada 2.59-ganda and 1.63-ganda. Namun demikian, pra-rawatan sel dengan perencat laluan isyarat NF-κB melumpuhkan peningkatkan tersebut dan kemudian mengurangkan ekspresi APOA-I dalam sel HepG2. Sebagai rumusan, kajian ini berjaya mengenalpasti peranan isyarat NF-κB dan pengaktifan p65 Ser468 dan Ser536 sebagai pengantara IFN-γ ke atas induksi APOA-I di dalam sel-sel HepG2.
Coral reefs in the northern region of the Straits of Malacca have a diverse group
of octocorals growing on its bed. The octocorals identified in this study are from islands
along the Straits. In this study, 23 specimens were identified, belonging to 4 sub-orders,
which have been subdivided into 8 families. From these 8 families, 15 different genera
have been identified. The identification process for this research was conducted based on
five important keys; the external form and colouration, polyps or colonial and fundamental
structure of colonies, monomorphic or dimorphic, the arrangement of polyps, and the
arrangement of sclerites.
Three Malaysian ginger cultivars (Bukit Tinggi, Tanjung Sepat and Sabah) were collected and examined for genetic polymorphisms using microsatellite DNA primers. The single microsatellite oligonucleotide primers (CATA)5, (GATA)5 and (GAC)6 were used in polymerase chain reactions (PCRs). These PCR reactions produced 7 polymorphic bands with an average of 2.334 polymorphic bands per primer, leading to an average polymorphism rate of 17.9%. Cluster analysis revealed 87.50% similarity between Bukit Tinggi and Tanjung Sepat, 64.27% similarity between Bukit Tinggi and Sabah and 56.25% similarity between Tanjung Sepat and Sabah. DNA sequencing of the polymorphic PCR products of Tanjung Sepat ginger revealed the characteristic features of a putative new gene: a core promoter sequence, an enhancer and a transcription start site. Cluster analysis using the unweighted pair group method with arithmetic average (UPGMA) was used to construct a phylogenetic tree, which indicated that Bukit Tinggi ginger is genetically more closely related to Tanjung Sepat ginger than to Sabah ginger. Based on the results of this study, we concluded that there is genotypic variation among ginger cultivars, and the microsatellite DNA primers described here are useful for detecting polymorphic DNA in Malaysian ginger cultivars. Additionally, these microsatellite DNA primers may be used as molecular markers for discriminating among select Malaysian ginger cultivars.
Contamination of paddy seeds (rice with husk) by Fusarium species can cause spoilage and subsequent production of mycotoxins, especially fumonisins that affect human and animal health. A mycological study was conducted to evaluate the natural occurrence of fumonisin B1 produced by Fusarium proliferatum on paddy grown in different geographic regions of Karnataka (India). A total of 65 isolates of F. proliferatum from paddy samples were analysed by polymerase chain reaction (PCR). One set of primers, Fp3-F and Fp4-R was employed to identify the species F. proliferatum, and another set of primers, FUM1 was employed to determine the fumonisin producing ability of the isolates. All 65 isolates of F. proliferatum scored positive with both set of primers, producing amplified products of the expected sizes. Furthermore, thin layer chromatography (TLC) analysis detected fumonisin B1 (FB1) in all of the PCR positive isolates of F. proliferatum.
The pteridophyte flora of Langkawi Archipelago consists of 130 species, 1 subspecies and 12 varieties in 68 genera and 27 families. This value represents 22.1% of the 647 taxa at the species level and below reported for Peninsular Malaysia. Of the 143 recorded taxa of pteridophytes at the species level and below, 8 species in 2 genera and 2 families are lycophytes and the other 135 taxa in 66 genera and 25 families are monilophytes or ferns.
Nine soil samples from nine buildings infested with Coptotermes gestroi in Pulau Pinang, Malaysia, were tested for the type of soil texture. The soil texture analysis procedures used the hydrometer method. Four of nine buildings (44%) yielded loamy sand-type soil, whereas five of nine buildings (56%) contained sandy loam-type soil.
Fusarium is a cosmopolitan and highly diversified genus of saprophytic, phytopathogenic and toxigenic fungi. However, the existence and diversity of a few species of Fusarium are restricted to a certain area or climatic condition. The present study was conducted to determine the occurrence and diversity of Fusarium species in tropical highland areas in Malaysia and to compare with those in temperate and subtropical regions. A series of sampling was carried out in 2005 to 2009 at several tropical highland areas in Malaysia that is: Cameron Highlands, Fraser Hills and Genting Highlands in Pahang; Penang Hill in Penang; Gunung Jerai in Kedah; Kundasang and Kinabalu Park in Sabah; Kubah National Park and Begunan Hill in Sarawak. Sampling was done randomly from various hosts and substrates. Isolation of Fusarium isolates was done by using pentachloronitrobenzene (PCNB) agar and 1449 isolates of Fusarium were successfully recovered. Based on morphological characteristics, 20 species of Fusarium were identified. The most prevalent species occurring on the highlands areas was F. solani (66.1%) followed by F. graminearum (8.5%), F. oxysporum (7.8%), F. semitectum (5.7%), F. subglutinans (3.5%) and F. proliferatum (3.4%). Other Fusarium species, namely F. avenaceum, F. camptoceras, F. chlamydosporum, F. compactum, F. crookwellense, F. culmorum, F. decemcellulare, F. equiseti, F. nygamai, F. poae, F. proliferatum, F. sacchari, F. sporotrichioides, F. sterilihyphosum and F. verticillioides accounted for 1% recoveries. The present study was the first report on the occurrences of Fusarium species on highland areas in Malaysia.
The status and distribution of Mimosa pigra L., a semi-aquatic invasive species in Peninsular Malaysia, were continuously assessed between 2004 and 2007. This assessment investigated its population stand density and related weed management activities. In total, 106 sites of 6 main habitat types i.e., construction site (CS), dam/ reservoir (DM), forest reserve (FR), plantation (PL), river bank/waterway (RB) and roadside (RD) were assessed, and 55 sites were recorded with M. pigra populations. A CS is the most likely habitat to be infested with M. pigra (16 out of 18 assessed sites have this weed), whereas none of the FR visited were found to harbour M. pigra. In terms of population stand density, 41 populations were in the low range of stand density (individual plant of ≤5 m(-2)), compared to only 9 populations in the high range of stand density (individual plant of >10 m(-2)). In general, the current impact of M. pigra infestation on natural habitats is relatively low, as its distribution is only confined to disturbed areas. However, continuous monitoring of this weed species is highly recommended, especially in the riparian zone and wetland habitats.
Bird surveys were conducted in the Bukit Kepala Gajah limestone area in Lenggong, Perak from July 2010 to January 2011. The study area was divided into three zones: forest edge, forest intermediate and forest interior. A point-count distance sampling method was used in the bird surveys. The study recorded 7789 detections, representing 100 bird species belonging to 28 families. Pycnonotidae, Timaliidae and Nectariniidae were the dominant families overall and showed the highest number of observations recorded in the study area whereas Motacillidae showed the fewest observations. The bird species were grouped into three feeding guilds: insectivores, frugivores and others (omnivores, carnivores, nectarivores and granivores). The species richness of insectivorous birds differed significantly among the forest zones sampled (Kruskal-Wallis: α=0.05, H=10.979, d.f.=2, p=0.004), with more insectivorous birds occurring in the forest interior. No significant differences were found among the zones in the species richness of either the frugivore guild or the composite others guild.