Displaying publications 21 - 40 of 99 in total

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  1. Chrotacumines E and F, two new chromone-alkaloid analogs from Dysoxylum acutangulum (Meliaceae) leaves
    Izwan Mohd Lazim M, Safinar Ismail I, Shaari K, Abd Latip J, Ali Al-Mekhlafi N, Morita H
    Chem Biodivers, 2013 Sep;10(9):1589-96.
    PMID: 24078592 DOI: 10.1002/cbdv.201200391
    A chemical investigation of the alkaloidal fraction of Dysoxylum acutangulum leaves led to the isolation and characterization of two new chromone alkaloid analogs named chrotacumines E and F (1 and 2, resp.). Structure elucidation of 1 and 2 was achieved by spectroscopic analyses, including 2D-NMR. Both of these alkaloids exhibited modest activities as tyrosinase inhibitors with 29.2 and 25.8% inhibition at 100 μg/ml, respectively.
    Matched MeSH terms: Plant Leaves/metabolism*
  2. Fulltext Comparative metabolomics analysis reveals alkaloid repertoires in young and mature Mitragyna speciosa (Korth.) Havil. Leaves
    Veeramohan R, Zamani AI, Azizan KA, Goh HH, Aizat WM, Razak MFA, et al.
    PLoS One, 2023;18(3):e0283147.
    PMID: 36943850 DOI: 10.1371/journal.pone.0283147
    The fresh leaves of Mitragyna speciosa (Korth.) Havil. have been traditionally consumed for centuries in Southeast Asia for its healing properties. Although the alkaloids of M. speciosa have been studied since the 1920s, comparative and systematic studies of metabolite composition based on different leaf maturity levels are still lacking. This study assessed the secondary metabolite composition in two different leaf stages (young and mature) of M. speciosa, using an untargeted liquid chromatography-electrospray ionisation-time-of-flight-mass spectrometry (LC-ESI-TOF-MS) metabolite profiling. The results revealed 86 putatively annotated metabolite features (RT:m/z value) comprising 63 alkaloids, 10 flavonoids, 6 terpenoids, 3 phenylpropanoids, and 1 of each carboxylic acid, glucoside, phenol, and phenolic aldehyde. The alkaloid features were further categorised into 14 subclasses, i.e., the most abundant class of secondary metabolites identified. As per previous reports, indole alkaloids are the most abundant alkaloid subclass in M. speciosa. The result of multivariate analysis (MVA) using principal component analysis (PCA) showed a clear separation of 92.8% between the young and mature leaf samples, indicating a high variance in metabolite levels between them. Akuammidine, alstonine, tryptamine, and yohimbine were tentatively identified among the many new alkaloids reported in this study, depicting the diverse biological activities of M. speciosa. Besides delving into the knowledge of metabolite distribution in different leaf stages, these findings have extended the current alkaloid repository of M. speciosa for a better understanding of its pharmaceutical potential.
    Matched MeSH terms: Plant Leaves/metabolism
  3. Fulltext Comparative transcriptome analysis to identify candidate genes involved in 2-methoxy-1,4-naphthoquinone (MNQ) biosynthesis in Impatiens balsamina L
    Foong LC, Chai JY, Ho ASH, Yeo BPH, Lim YM, Tam SM
    Sci Rep, 2020 09 30;10(1):16123.
    PMID: 32999341 DOI: 10.1038/s41598-020-72997-2
    Impatiens balsamina L. is a tropical ornamental and traditional medicinal herb rich in natural compounds, especially 2-methoxy-1,4-naphthoquinone (MNQ) which is a bioactive compound with tested anticancer activities. Characterization of key genes involved in the shikimate and 1,4-dihydroxy-2-naphthoate (DHNA) pathways responsible for MNQ biosynthesis and their expression profiles in I. balsamina will facilitate adoption of genetic/metabolic engineering or synthetic biology approaches to further increase production for pre-commercialization. In this study, HPLC analysis showed that MNQ was present in significantly higher quantities in the capsule pericarps throughout three developmental stages (early-, mature- and postbreaker stages) whilst its immediate precursor, 2-hydroxy-1,4-naphthoquinone (lawsone) was mainly detected in mature leaves. Transcriptomes of I. balsamina derived from leaf, flower, and three capsule developmental stages were generated, totalling 59.643 Gb of raw reads that were assembled into 94,659 unigenes (595,828 transcripts). A total of 73.96% of unigenes were functionally annotated against seven public databases and 50,786 differentially expressed genes (DEGs) were identified. Expression profiles of 20 selected genes from four major secondary metabolism pathways were studied and validated using qRT-PCR method. Majority of the DHNA pathway genes were found to be significantly upregulated in early stage capsule compared to flower and leaf, suggesting tissue-specific synthesis of MNQ. Correlation analysis identified 11 candidate unigenes related to three enzymes (NADH-quinone oxidoreductase, UDP-glycosyltransferases and S-adenosylmethionine-dependent O-methyltransferase) important in the final steps of MNQ biosynthesis based on genes expression profiles consistent with MNQ content. This study provides the first molecular insight into the dynamics of MNQ biosynthesis and accumulation across different tissues of I. balsamina and serves as a valuable resource to facilitate further manipulation to increase production of MNQ.
    Matched MeSH terms: Plant Leaves/metabolism
  4. Construction of PHB and PHBV multiple-gene vectors driven by an oil palm leaf-specific promoter
    Masani MY, Parveez GK, Izawati AM, Lan CP, Siti Nor Akmar A
    Plasmid, 2009 Nov;62(3):191-200.
    PMID: 19699761 DOI: 10.1016/j.plasmid.2009.08.002
    One of the targets in oil palm genetic engineering programme is the production of polyhydroxybutyrate (PHB) and polyhydroxybutyrate-co-valerate (PHBV) in the oil palm leaf tissues. Production of PHB requires the use of phbA (beta-ketothiolase type A), phbB (acetoacetyl-CoA reductase) and phbC (PHB synthase) genes of Ralstonia eutropha, whereas bktB (beta-ketothiolase type B), phbB, phbC genes of R. eutropha and tdcB (threonine dehydratase) gene of Escherichia coli were used for PHBV production. Each of these genes was fused with a transit peptide (Tp) of oil palm acyl-carrier-protein (ACP) gene, driven by an oil palm leaf-specific promoter (LSP1) to genetically engineer the PHB/PHBV pathway to the plastids of the leaf tissues. In total, four transformation vectors, designated pLSP15 (PHB) and pLSP20 (PHBV), and pLSP13 (PHB) and pLSP23 (PHBV), were constructed for transformation in Arabidopsis thaliana and oil palm, respectively. The phosphinothricin acetyltransferase gene (bar) driven by CaMV35S promoter in pLSP15 and pLSP20, and ubiquitin promoter in pLSP13 and pLSP23 were used as the plant selectable markers. Matrix attachment region of tobacco (RB7MAR) was also included in the vectors to stabilize the transgene expression and to minimize silencing due to positional effect. Restriction digestion, PCR amplification and/or sequencing were carried out to ensure sequence integrity and orientation.
    Matched MeSH terms: Plant Leaves/metabolism
  5. Fulltext Cryptic coloration of Macaranga bancana seedlings: A unique strategy for a pioneer species
    Fadzly N, Zuharah WF, Mansor A, Zakaria R
    Plant Signal Behav, 2016 07 02;11(7):e1197466.
    PMID: 27315145 DOI: 10.1080/15592324.2016.1197466
    Macaranga bancana is considered as a successful pioneer plant species. Usually found in disturbed and open areas, most of the current research focused on its relations with ants. One of the unique feature of the plants is that the seedling leaves are red, resembling and almost matching the background. Using a portable spectrometer, we measured the color reflectance of M. bancana seedlings (less than 20 cm in height). We also measured the leaf litter reflectance, adult M. bancana leaves and also seedlings of several other species found in the vicinity of M. bancana seedlings. The reflectances of M. bancana seedlings are very similar to that of the leaf litter background. We suggest that this cryptic coloration is crucial during the early stages of the plant when it still cannot rely on the protection of ants.
    Matched MeSH terms: Plant Leaves/metabolism
  6. Fulltext Defining the scope for altering rice leaf anatomy to improve photosynthesis: a modelling approach
    Xiao Y, Sloan J, Hepworth C, Fradera-Soler M, Mathers A, Thorley R, et al.
    New Phytol, 2023 Jan;237(2):441-453.
    PMID: 36271620 DOI: 10.1111/nph.18564
    Leaf structure plays an important role in photosynthesis. However, the causal relationship and the quantitative importance of any single structural parameter to the overall photosynthetic performance of a leaf remains open to debate. In this paper, we report on a mechanistic model, eLeaf, which successfully captures rice leaf photosynthetic performance under varying environmental conditions of light and CO2 . We developed a 3D reaction-diffusion model for leaf photosynthesis parameterised using a range of imaging data and biochemical measurements from plants grown under ambient and elevated CO2 and then interrogated the model to quantify the importance of these elements. The model successfully captured leaf-level photosynthetic performance in rice. Photosynthetic metabolism underpinned the majority of the increased carbon assimilation rate observed under elevated CO2 levels, with a range of structural elements making positive and negative contributions. Mesophyll porosity could be varied without any major outcome on photosynthetic performance, providing a theoretical underpinning for experimental data. eLeaf allows quantitative analysis of the influence of morphological and biochemical properties on leaf photosynthesis. The analysis highlights a degree of leaf structural plasticity with respect to photosynthesis of significance in the context of attempts to improve crop photosynthesis.
    Matched MeSH terms: Plant Leaves/metabolism
  7. Differential gene expression and characterization of tissue-specific cDNA clones in oil palm using mRNA differential display
    San CT, Shah FH
    Mol Biol Rep, 2005 Dec;32(4):227-35.
    PMID: 16328884
    The mRNA differential display method was utilized to study the differential expression and regulation of genes in two species of oil palm, the commercially grown variety Elaeis guineensis, var. tenera and the South American species, Elaeis oleifera. We demonstrated the differential expression of genes in the mesocarp and kernel at the week of active oil synthesis (15 week after anthesis) during fruit development as compare to the roots and leaves and the isolation of tissue-specific and species-specific cDNA clones. A total of eight specific cDNA clones were isolated and their specificities were confirmed by Northern hybridization and classified into three groups. Group one contains four clones (KT3, KT4, KT5 and KT6) that are kernel-specific for E. guineensis, tenera and E. oleifera. The second group represents clone FST1, which is mesocarp and kernel-specific for E. guineensis, tenera and E. oleifera. The third group represents clones MLT1, MLT2 and MLO1 that are mesocarp and leaf-specific. Northern analysis showed that their expressions were developmentally regulated. Nucleotide sequencing and homology search in GenBank data revealed that clones KT3 and KT4 encode for the same maturation protein PM3. While clones MLT1 and MLT2 encode for S-ribonuclease binding protein and fibrillin, respectively. The other clones (KT5, KT6, FST1 and MLO1) did not display any significant homology to any known protein.
    Matched MeSH terms: Plant Leaves/metabolism
  8. Digestion of rice straw and oil palm fronds by microflora from rumen and termite bacteria, in vitro
    Ramin M, Alimon AR, Panandam JM, Sijam K, Javanmard A, Abdullah N
    Pak J Biol Sci, 2008 Feb 15;11(4):583-8.
    PMID: 18817130
    The digestion and Volatile Fatty Acid (VFA) production from rice straw and oil palm fronds by cellulolytic bacteria isolated from the termite Coptotermes curvignathus were investigated. The bacteria were Acinetobacter strain Raminalimon, Enterobacter aerogenes strain Razmin C, Enterobacter cloacae strain Razmin B, Bacillus cereus strain Razmin A and Chryseobacterium kwangyangense strain Cb. Acinetobacter strain Raminalimon is an aerobic bacterium, while the other species are facultative anaerobes. There were significant differences (p<0.05) among the bacteria for Dry Matter (DM) lost and acetic acid production from rice straw and Acinetobacter strain Raminalimon showed the highest activity. The facultative bacteria C. kwangyangense strain Cb (cfu mL(-1) 231 x 10(-6), OD: 0.5), E. cloacae (cfu mL(-1) 68 x 10(-7), OD: 0.5) and E. aerogenes (cfu mL(-1) 33 x 10(-7), OD: 0.5) were used for digestion study with the rumen fluid microflora. The in vitro gas production technique was applied for the comparative study and the parameters measured were pH, gas (volume), dry matter lost, acetic acid, propionic acid and butyric acid concentrations. pH was not significantly (p<0.05) different among the five treatments. The bacterium C. kwangyangense strain Cb showed the highest activity (p<0.05) for DM lost, acetic acid, propionic acid and butyric acid production from rice straw when compared to the other bacterial activities. There was no significance (p<0.05) difference between the three bacteria for the dry matter lost of oil palm fronds but the production of Volatile Fatty Acids (VFA) was significantly (p<0.05) high in the treatment which was inoculated with C. kwangyangense strain Cb. The Gen Bank NCBI/EMBL accession numbers for the bacterial strains are EU332791, EU305608, EU305609, EU294508 and EU169201.
    Matched MeSH terms: Plant Leaves/metabolism*
  9. Fulltext Diurnal biomarkers reveal key photosynthetic genes associated with increased oil palm yield
    Neoh BK, Wong YC, Teh HF, Ng TLM, Tiong SH, Ooi TEK, et al.
    PLoS One, 2019;14(3):e0213591.
    PMID: 30856213 DOI: 10.1371/journal.pone.0213591
    To investigate limiters of photosynthate assimilation in the carbon-source limited crop, oil palm (Elaeis guineensis Jacq.), we measured differential metabolite, gene expression and the gas exchange in leaves in an open field for palms with distinct mesocarp oil content. We observed higher concentrations of glucose 1-phosphate, glucose 6-phosphate, sucrose 6-phosphate, and sucrose in high-oil content palms with the greatest difference being at 11:00 (p-value ≤0.05) immediately after the period of low morning light intensity. Three important photosynthetic genes were identified using differentially expressed gene analysis (DEGs) and were found to be significantly enriched through Gene Ontology (GO) and pathway enrichment: chlorophyll a-b binding protein (CAB-13), photosystem I (PSI), and Ferredoxin-NADP reductase (FNR), particularly for sampling points at non-peak light (11:00 and 19:00), ranging from 3.3-fold (PSI) and 5.6-fold (FNR) to 10.3-fold (CAB-13). Subsequent gas exchange measurements further supported increased carbon assimilation through higher level of internal CO2 concentration (Ci), stomatal conductance (gs) and transpiration rate (E) in high-oil content palms. The selection for higher expression of key photosynthesis genes together with CO2 assimilation under low light is likely to be important for crop improvement, in particular at full maturity and under high density planting regimes where light competition exists between palms.
    Matched MeSH terms: Plant Leaves/metabolism
  10. Fulltext Effect of CO(2) enrichment on synthesis of some primary and secondary metabolites in ginger (Zingiber officinale Roscoe)
    Ghasemzadeh A, Jaafar HZ
    Int J Mol Sci, 2011 Feb 10;12(2):1101-14.
    PMID: 21541046 DOI: 10.3390/ijms12021101
    The effect of two different CO(2) concentrations (400 and 800 μmol mol(-1)) on the photosynthesis rate, primary and secondary metabolite syntheses and the antioxidant activities of the leaves, stems and rhizomes of two Zingiber officinale varieties (Halia Bentong and Halia Bara) were assessed in an effort to compare and validate the medicinal potential of the subterranean part of the young ginger. High photosynthesis rate (10.05 μmol CO(2) m(-2)s(-1) in Halia Bara) and plant biomass (83.4 g in Halia Bentong) were observed at 800 μmol mol(-1) CO(2). Stomatal conductance decreased and water use efficiency increased with elevated CO(2) concentration. Total flavonoids (TF), total phenolics (TP), total soluble carbohydrates (TSC), starch and plant biomass increased significantly (P ≤ 0.05) in all parts of the ginger varieties under elevated CO(2) (800 μmol mol(-1)). The order of the TF and TP increment in the parts of the plant was rhizomes > stems > leaves. More specifically, Halia Bara had a greater increase of TF (2.05 mg/g dry weight) and TP (14.31 mg/g dry weight) compared to Halia Bentong (TF: 1.42 mg/g dry weight; TP: 9.11 mg/g dry weight) in average over the whole plant. Furthermore, plants with the highest rate of photosynthesis had the highest TSC and phenolics content. Significant differences between treatments and species were observed for TF and TP production. Correlation coefficient showed that TSC and TP content are positively correlated in both varieties. The antioxidant activity, as determined by the ferric reducing/antioxidant potential (FRAP) activity, increased in young ginger grown under elevated CO(2). The FRAP values for the leaves, rhizomes and stems extracts of both varieties grown under two different CO(2) concentrations (400 and 800 μmol mol(-1)) were significantly lower than those of vitamin C (3107.28 μmol Fe (II)/g) and α-tocopherol (953 μmol Fe (II)/g), but higher than that of BHT (74.31 μmol Fe (II)/g). These results indicate that the plant biomass, primary and secondary metabolite synthesis, and following that, antioxidant activities of Malaysian young ginger varieties can be enhanced through controlled environment (CE) and CO(2) enrichment.
    Matched MeSH terms: Plant Leaves/metabolism
  11. Effect of autohydrolysis and enzymatic treatment on oil palm (Elaeis guineensis Jacq.) frond fibres for xylose and xylooligosaccharides production
    Sabiha-Hanim S, Noor MA, Rosma A
    Bioresour Technol, 2011 Jan;102(2):1234-9.
    PMID: 20797853 DOI: 10.1016/j.biortech.2010.08.017
    Oil palm (Elaeis guineensis Jacq.) is one of the most important commercial crops for the production of palm oil, which generates 10.88 tons of oil palm fronds per hectare of plantation as a by-product. In this study, oil palm frond fibres were subjected to an autohydrolysis treatment using an autoclave, operated at 121 °C for 20-80 min, to facilitate the separation of hemicelluloses. The hemicellulose-rich solution (autohydrolysate) was subjected to further hydrolysis with 4-16 U of mixed Trichoderma viride endo-(1,4)-β-xylanases (EC 3.2.1.8) per 100 mg of autohydrolysate. Autoclaving of palm fronds at 121°C for 60 min (a severity factor of 2.40) recovered 75% of the solid residue, containing 57.9% cellulose and 18% Klason lignin, and an autohydrolysate containing 14.94% hemicellulose, with a fractionation efficiency of 49.20%. Subsequent enzymatic hydrolysis of the autohydrolysate with 8 U of endoxylanase at 40 °C for 24 h produced a solution containing 17.5% xylooligosaccharides and 25.6% xylose. The results clearly indicate the potential utilization of oil palm frond, an abundantly available lignocellulosic biomass for the production of xylose and xylooligosaccharides which can serve as functional food ingredients.
    Matched MeSH terms: Plant Leaves/metabolism*
  12. Fulltext Effects of acute gamma irradiation on physiological traits and flavonoid accumulation of Centella asiatica
    Moghaddam SS, Jaafar H, Ibrahim R, Rahmat A, Aziz MA, Philip E
    Molecules, 2011 Jun 17;16(6):4994-5007.
    PMID: 21694666 DOI: 10.3390/molecules16064994
    In the present study, two accessions of Centella asiatica (CA03 and CA23) were subjected to gamma radiation to examine the response of these accessions in terms of survival rate, flavonoid contents, leaf gas exchange and leaf mass. Radiation Sensitivity Tests revealed that based on the survival rate, the LD(50) (gamma doses that killed 50% of the plantlets) of the plantlets were achieved at 60 Gy for CA03 and 40 Gy for CA23. The nodal segments were irradiated with gamma rays at does of 30 and 40 Gy for Centella asiatica accession 'CA03' and 20 and 30 Gy for accession 'CA23. The nodal segment response to the radiation was evaluated by recording the flavonoid content, leaf gas exchange and leaf biomass. The experiment was designed as RCBD with five replications. Results demonstrated that the irradiated plantlets exhibited greater total flavonoid contents (in eight weeks) significantly than the control where the control also exhibited the highest total flavonoid contents in the sixth week of growth; 2.64 ± 0.02 mg/g DW in CA03 and 8.94 ± 0.04 mg/g DW in CA23. The total flavonoid content was found to be highest after eight weeks of growth, and this, accordingly, stands as the best time for leaf harvest. Biochemical differentiation based on total flavonoid content revealed that irradiated plantlets in CA23 at 20 and 30 Gy after eight weeks contained the highest total flavonoid concentrations (16.827 ± 0.02; 16.837 ± 0.008 mg/g DW, respectively) whereas in CA03 exposed to 30 and 40 Gy was found to have the lowest total flavonid content (5.83 ± 0.11; 5.75 ± 0.03 mg/g DW). Based on the results gathered in this study, significant differences were found between irradiated accessions and control ones in relation to the leaf gas. The highest PN and gs were detected in CA23 as control followed by CA23 irradiated to 20Gy (CA23G20) and CA23G30 and the lowest PN and gs were observed in CA03 irradiated to 40Gy (CA03G40). Moreover, there were no significant differences in terms of PN and gs among the irradiated plants in each accession. The WUE of both irradiated accessions of Centella asiatica were reduced as compared with the control plants (p < 0.01) while Ci and E were enhanced. There were no significant differences in the gas exchange parameters among radiated plants in each accession. Moreover, malondialdehyde (MDA) of accessions after gamma treatments were significantly higher than the control, however, flavonoids which were higher concentration in irradiated plants can scavenge surplus free radicals. Therefore, the findings of this study have proven an efficient method of in vitro mutagenesis through gamma radiation based on the pharmaceutical demand to create economically superior mutants of C. asiatica. In other words, the results of this study suggest that gamma irradiation on C. asiatica can produce mutants of agricultural and economical importance.
    Matched MeSH terms: Plant Leaves/metabolism
  13. Fulltext Effects of dietary Kleinhovia hospita and Leucaena leucocephala leaves on rumen fermentation and microbial population in goats fed treated rice straw
    Ahmed MA, Adeyemi KD, Jahromi MF, Jusoh S, Alimon AR, Samsudin AA
    Trop Anim Health Prod, 2017 Dec;49(8):1749-1756.
    PMID: 28849307 DOI: 10.1007/s11250-017-1388-3
    The effects of partial replacement of dietary protein by forages on rumen fermentation and microbiology in goats were examined. Four fistulated Boer bucks were used in a 4 × 4 Latin square design. The goats were fed 60% of urea-treated rice straw and 40% dietary treatment (Kleinhovia hospita (KH), Leucaena leucocephala (LL), mixture of K. hospita with L. leucocephala (KHLL)) and concentrate as the control. Rumen fluid from the animals was collected at 0, 2, 4, 6, and 12 h postprandial for analysis. The KHLL diet had a greater (P 
    Matched MeSH terms: Plant Leaves/metabolism
  14. Effects of gamma radiation treatment on three different medicinal plants: Microbial limit test, total phenolic content, in vitro cytotoxicity effect and antioxidant assay
    Khawory MH, Amat Sain A, Rosli MAA, Ishak MS, Noordin MI, Wahab HA
    Appl Radiat Isot, 2020 Mar;157:109013.
    PMID: 31889674 DOI: 10.1016/j.apradiso.2019.109013
    BACKGROUND AND AIM: The aim of this study is to evaluate the effects of gamma radiation treatment on three medicinal plants, namely Euodia malayana, Gnetum gnemon and Khaya senegalensis at two different forms; methanol leaf extracts and dried leaves respectively.

    EXPERIMENTAL PROCEDURE: The microbial limit test (MLT) studies indicated the suitable dosage of minimum and maximum gamma irradiation for leaf extracts as well as dried leaves of all the tested medicinal plants. Quantitative analysis of total phenolic content (TPC) analysis is based on calorimetric measurements determined using the Folin-Ciocalteu reagent with gallic acid (GA) used as the reference. In vitro cytotoxicity assay by using fibroblast (L929) cell lines was performed on each plant to determine the toxicity effect which sodium dodecyl sulfate (SDS) as the positive control. DPPH (2,2-diphenyl-1-picryl-hydrazyl) assay was conducted by using vitamin C and GA as the positive controls to determine the antioxidant property of each plant.

    RESULTS AND CONCLUSION: The MLT analysis indicated that the suitable dosage gamma irradiation for leaf extracts was 6-12 kGy and dried leaves were 9-13 kGy. The amount of GA concentration in each plant increased significantly from 30-51 mg GAE g-1 before treatment to 57-103 mg GAE g-1 after treatment with gamma radiation. This showed no significant effect of in vitro cytotoxicity activity before and after treatment with gamma irradiation in this study. Effective concentration (EC50) values of Khaya senegalensis plant reduced significantly (P ≤ 0.005) from 44.510 μg/ml before treatment to 24.691 μg/ml after treatment with gamma radiation, which indicate an increase of free radical scavenging activity.

    Matched MeSH terms: Plant Leaves/metabolism
  15. Fulltext Effects of nitrogen fertilization on synthesis of primary and secondary metabolites in three varieties of Kacip Fatimah (Labisia pumila Blume)
    Ibrahim MH, Jaafar HZ, Rahmat A, Rahman ZA
    Int J Mol Sci, 2011;12(8):5238-54.
    PMID: 21954355 DOI: 10.3390/ijms12085238
    A split plot 3 by 4 experiment was designed to examine the impact of 15-week variable levels of nitrogen fertilization (0, 90, 180 and 270 kg N/ha) on the characteristics of total flavonoids (TF), total phenolics (TP), total non structurable carbohydrate (TNC), net assimilation rate, leaf chlorophyll content, carbon to nitrogen ratio (C/N), phenyl alanine lyase activity (PAL) and protein content, and their relationships, in three varieties of Labisia pumila Blume (alata, pumila and lanceolata). The treatment effects were solely contributed by nitrogen application; there was neither varietal nor interaction effect observed. As nitrogen levels increased from 0 to 270 kg N/ha, the production of TNC was found to decrease steadily. Production of TF and TP reached their peaks under 0 followed by 90, 180 and 270 kg N/ha treatment. However, net assimilation rate was enhanced as nitrogen fertilization increased from 0 to 270 kg N/ha. The increase in production of TP and TF under low nitrogen levels (0 and 90 kg N/ha) was found to be correlated with enhanced PAL activity. The enhancement in PAL activity was followed by reduction in production of soluble protein under low nitrogen fertilization indicating more availability of amino acid phenyl alanine (phe) under low nitrogen content that stimulate the production of carbon based secondary metabolites (CBSM). The latter was manifested by high C/N ratio in L. pumila plants.
    Matched MeSH terms: Plant Leaves/metabolism
  16. Enhanced photocatalysis and anticancer activity of green hydrothermal synthesized Ag@TiO2 nanoparticles
    Hariharan D, Thangamuniyandi P, Jegatha Christy A, Vasantharaja R, Selvakumar P, Sagadevan S, et al.
    J. Photochem. Photobiol. B, Biol., 2020 Jan;202:111636.
    PMID: 31739259 DOI: 10.1016/j.jphotobiol.2019.111636
    Titanium dioxide (TiO2) nanoparticles (NPs) have been doped with varying amounts (0.005, 0.010 and 0.015 M) of silver nanoparticles (Ag NPs) using hydrothermal method. Further, in this work, a green approach was followed for the formation of Ag@TiO2 NPs using Aloe vera gel as a capping and reducing agent. The structural property confirmed the presence of anatase phase TiO2. Increased peak intensity was observed while increasing the Ag concentration. Further, the morphological and optical properties have been studied, which confirmed the effective photocatalytic behavior of the prepared Ag@TiO2 NPs. The photocatalytic performance of Ag@TiO2 has been considered for the degradation of picric acid in the visible light region. The concentration at 0.010 M of the prepared Ag@TiO2 has achieved higher photocatalytic performance within 50 min, which could be attributed to its morphological behavior. Similarly, anticancer activity against lung cancer cell lines (A549) was also determined. The Ag@TiO2 NPs generated a large quantity of reactive oxygen species (ROS), resulting in complete cancer cell growth suppression after their systemic in vitro administration. Ag@TiO2 NPs was adsorbed visible light that leads to an enhanced anticancer sensitivity by killing and inhibiting cancer cell reproduction through cell viability assay test. It was clear that 0.015 M of Ag@TiO2 NPs were highly effective against human lung cancer cell lines and showed increased production of ROS in cancer cell lines due to the medicinal behavior of the Aloe vera gel.
    Matched MeSH terms: Plant Leaves/metabolism
  17. Fulltext Enhancement of leaf gas exchange and primary metabolites under carbon dioxide enrichment up-regulates the production of secondary metabolites in Labisia pumila seedlings
    Ibrahim MH, Jaafar HZ
    Molecules, 2011 May 04;16(5):3761-77.
    PMID: 21544039 DOI: 10.3390/molecules16053761
    A split plot 3 by 3 experiment was designed to investigate and distinguish the relationships among production of primary metabolites (soluble sugar and starch), secondary metabolites (total phenolics, TP; total flavonoids, TF) and leaf gas exchange of three varieties of the Malaysian medicinal herb Labisia pumila Blume, namely the varieties alata, pumila and lanceolata, under three levels of CO₂ enrichment (400, 800 and 1,200 µmol mol⁻¹) for 15 weeks. The treatment effects were solely contributed by CO₂ enrichment levels; no varietal differences were observed. As CO₂ levels increased from 400 to 1,200 µmol mol⁻¹, the production of carbohydrates also increased steadily, especially for starch more than soluble sugar (sucrose). TF and TP content, simultaneously, reached their peaks under 1,200 µmol exposure, followed by 800 and 400 µmol mol⁻¹. Net photosynthesis (A) and quantum efficiency of photosystem II (f(v)/f(m)) were also enhanced as CO₂ increased from 400 to 1,200 µmol mol⁻¹. Leaf gas exchange characteristics displayed a significant positive relationship with the production of secondary metabolites and carbohydrate contents. The increase in production of TP and TFs were manifested by high C/N ratio and low protein content in L. pumila seedlings, and accompanied by reduction in cholorophyll content that exhibited very significant negative relationships with total soluble sugar, starch and total non structural carbohydrate.
    Matched MeSH terms: Plant Leaves/metabolism*
  18. Evaluation of ethnopharmacologically selected Vitex negundo L. for In vitro antimalarial activity and secondary metabolite profiling
    Dwivedi MK, Shukla R, Sharma NK, Manhas A, Srivastava K, Kumar N, et al.
    J Ethnopharmacol, 2021 Jul 15;275:114076.
    PMID: 33789139 DOI: 10.1016/j.jep.2021.114076
    ETHANOPHARMACOLOGICAL RELEVANCE: Limited drugs, rise in drug resistance against frontline anti-malarial drugs, non-availability of efficacious vaccines and high cost of drug development hinders malaria intervention programs. Search for safe, effective and affordable plant based anti-malarial agents, thus becomes crucial and vital in the current scenario. The Vitex negundo L. is medicinal plant possessing a variety of pharmaceutically important compounds. The plant is used traditionally worldwide for the treatment of malaria including India and Malaysia by the indigenous tribes. In vitro studies have reported the anti-malarial use of the plant in traditional medicinal systems.

    AIM OF THE STUDY: The aim of the current study is to evaluate the traditionally used medicinal plants for in vitro anti-malarial activity against human malaria parasite Plasmodium falciparum and profiling secondary metabolite using spectroscopic and chromatographic methods. Chemical profiling of active secondary metabolites in the extracts was undertaken using LC-MS.

    MATERIALS AND METHODS: Based on the ethno-botanical data V. negundo L. was selected for in vitro anti-malarial activity against P. falciparum chloroquine-sensitive (3D7) and multidrug resistant (K1) strains using SYBR Green-I based fluorescence assay. Cytotoxicity of extracts was evaluated in VERO cell line using the MTT assay. Haemolysis assay was performed using human red blood cells. Secondary metabolites profiling was undertaken using chromatographic and spectroscopic analysis. Liquid chromatography analysis was performed using a C18, 150 X 2.1, 2.6 μm column with gradient mobile phase Solvent A: 95% (H2O: ACN), Solvent B: Acetonitrile, Solvent C: Methanol, Solvent D: 5 mM NH4 in 95:5 (H2O: ACN) at a constant flow rate of 0.250 ml/min. The LC-MS spectra were acquired in both positive and negative ion modes with electrospray ionization (ESI) source.

    RESULTS: The anti-malarial active extract of V. negundo L. leaf exhibited potent anti-malarial activity with IC50 values of 7.21 μg/ml and 7.43 μg/ml against 3D7 and K1 strains, respectively with no evidence of significant cytotoxicity against mammalian cell line (VERO) and no toxicity as observed in haemolysis assay. The HPLC-LC-MS analysis of the extract led to identification of 73 compounds. We report for the first time the presence of Sabinene hydrate acetate, 5-Hydroxyoxindole, 2(3,4-dimethoxyphenyl)-6, 7-dimethoxychromen-4-one, Cyclotetracosa-1, 13-diene and 5, 7-Dimethoxyflavanone in the anti-malarial active extract of V. negundo L. leaf. Agnuside, Behenic acid and Globulol are some of the novel compounds with no reports of anti-malarial activity so far and require further evaluation in pure form for the development of potent anti-malarial compounds.

    CONCLUSIONS: The result report and scientifically validate the traditional use of V. negundo L. for the treatment of malaria providing new avenues for anti-malarial drug development. Several novel and unknown compounds were identified that need to be further characterized for anti-malarial potential.

    Matched MeSH terms: Plant Leaves/metabolism*
  19. Fulltext Expression patterns of genes involved in the defense and stress response of Spiroplasma citri infected Madagascar Periwinkle Catharanthus roseus
    Nejat N, Vadamalai G, Dickinson M
    Int J Mol Sci, 2012;13(2):2301-2313.
    PMID: 22408455 DOI: 10.3390/ijms13022301
    Madagascar periwinkle is an ornamental and a medicinal plant, and is also an indicator plant that is highly susceptible to phytoplasma and spiroplasma infections from different crops. Periwinkle lethal yellows, caused by Spiroplasma citri, is one of the most devastating diseases of periwinkle. The response of plants to S. citri infection is very little known at the transcriptome level. In this study, quantitative real-time PCR (RT-qPCR) was used to investigate the expression levels of four selected genes involved in defense and stress responses in naturally and experimentally Spiroplasma citri infected periwinkles. Strictosidine β-glucosidase involved in terpenoid indole alkaloids (TIAs) biosynthesis pathway showed significant upregulation in experimentally and naturally infected periwinkles. The transcript level of extensin increased in leaves of periwinkles experimentally infected by S. citri in comparison to healthy ones. A similar level of heat shock protein 90 and metallothionein expression was observed in healthy, naturally and experimentally spiroplasma-diseased periwinkles. Overexpression of Strictosidine β-glucosidase demonstrates the potential utility of this gene as a host biomarker to increase the fidelity of S. citri detection and can also be used in breeding programs to develop stable disease-resistance varieties.
    Matched MeSH terms: Plant Leaves/metabolism
  20. Expression profiles of putative defence-related proteins in oil palm (Elaeis guineensis) colonized by Ganoderma boninense
    Tan YC, Yeoh KA, Wong MY, Ho CL
    J Plant Physiol, 2013 Nov 01;170(16):1455-60.
    PMID: 23769496 DOI: 10.1016/j.jplph.2013.05.009
    Basal stem rot (BSR) is a major disease of oil palm caused by a pathogenic fungus, Ganoderma boninense. However, the interaction between the host plant and its pathogen is not well characterized. To better understand the response of oil palm to G. boninense, transcript profiles of eleven putative defence-related genes from oil palm were measured by quantitative reverse-transcription (qRT)-PCR in the roots of oil palms treated with G. boninense from 3 to 12 weeks post infection (wpi). These transcripts encode putative Bowman-Birk serine protease inhibitors (EgBBI1 and 2), defensin (EgDFS), dehydrin (EgDHN), early methionine-labeled polypeptides (EgEMLP1 and 2), glycine-rich RNA binding protein (EgGRRBP), isoflavone reductase (EgIFR), metallothionein-like protein (EgMT), pathogenesis-related-1 protein (EgPRP), and type 2 ribosome-inactivating protein (EgT2RIP). The transcript abundance of EgBBI2 increased in G. boninense-treated roots at 3 and 6wpi compared to those of controls; while the transcript abundance of EgBBI1, EgDFS, EgEMLP1, EgMT, and EgT2RIP increased in G. boninense-treated roots at 6 or 12wpi. Meanwhile, the gene expression of EgDHN was up-regulated at all three time points in G. boninense-treated roots. The expression profiles of the eleven transcripts were also studied in leaf samples upon inoculation of G. boninense and Trichoderma harzianum to identify potential biomarkers for early detection of BSR. Two candidate genes (EgEMLP1 and EgMT) that have different profiles in G. boninense-treated leaves compared to those infected by T. harzianum may have the potential to be developed as biomarkers for early detection of G. boninense infection.
    Matched MeSH terms: Plant Leaves/metabolism
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