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  1. Agatonovic-Kustrin S, Kustrin E, Angove MJ, Morton DW
    J Chromatogr A, 2018 May 18;1550:57-62.
    PMID: 29615323 DOI: 10.1016/j.chroma.2018.03.054
    The interaction of bioactive compounds from ethanolic extracts of selected marine algae samples, separated on chromatographic plates, with nitric/nitrous acid was investigated. The nature of bioactive compounds in the marine algae extracts was characterised using UV absorption spectra before and after reaction with diluted nitric acid, and from the characteristic colour reaction after derivatization with anisaldehyde. It was found that diterpenes from Dictyota dichotoma, an edible brown algae, and sterols from green algae Caulerpa brachypus, bind nitric oxide and may act as a nitric oxide carrier. Although the carotenoid fucoxanthin, found in all brown marine algae also binds nitric oxide, the bonds between nitrogen and the fucoxanthin molecule are much stronger. Further studies are required to evaluate the effects of diterpenes from Dictyota dichotoma and sterols from green algae Caulerpa brachypus to see if they have beneficial cardiovascular effects. The method reported here should prove useful in screening large numbers of algae species for compounds with cardiovascular activity.
    Matched MeSH terms: Chromatography, Thin Layer
  2. Farina Y, Munawar N, Abdullah MP, Yaqoob M, Nabi A
    Environ Monit Assess, 2018 Jun 09;190(7):386.
    PMID: 29884954 DOI: 10.1007/s10661-018-6762-8
    Occurrence and distribution of organochlorine pesticides (OCPs), organophosphate pesticides (OPPs), and pyrethroid pesticides (PYRs) residues in the leafy vegetables were analyzed together with the soil samples using gas chromatography-electron capture detector. Edible tissues of vegetables showed detectable residues of these compounds indicating the influence of the conventional farms and nearby organic farms. In the vegetables, the OCPs concentrations were recorded as nd-133.3 ng/g, OPPs as nd-200 ng/g, and PYRs as nd-33.3 ng/g. In the soil, the OCPs concentrations were recorded as nd-30.6 ng/g, OPPs as nd-26.6 ng/g, and for PYRs as nd-6.7 ng/g. Bioconcentration factor (BCF) was higher for the OPPs (0.3) than the OCPs and PYRs (1.1). The OCPs concentration in the vegetables decreased in the following order: spinach > celery > broccoli > cauliflower > cabbage > lettuce > mustard. For OPPs, the concentration decreased in the following order: cauliflower > spinach > celery > cabbage > broccoli > lettuce > mustard and for PYRs as spinach > celery > lettuce > cabbage > broccoli. Principal component analysis indicates that the sources of these pesticides are not the same, and the pesticide application on the vegetables depends on the type of crop. There is a significant positive correlation between OPPs and the soil (r = 0.65) as compared to OCPs and PYRs (r = 0.1) as the vegetables accumulated OPPs more efficiently than OCPs and PYRs.
    Matched MeSH terms: Chromatography, Gas
  3. Leong XF, Salimon J, Mustafa MR, Jaarin K
    Malays J Med Sci, 2012 Jan;19(1):20-9.
    PMID: 22977371
    BACKGROUND: Oxidative stress is associated with the pathogenesis of cardiovascular diseases. The process of deep-fat frying in dietary cooking oil plays a role in the generation of free radicals. In this study, palm olein heated to 180 °C was tested for its effect on the activity of blood pressure-regulating enzymes and lipid peroxidation.

    METHODS: Forty-two adult male Sprague-Dawley rats were equally assigned into 6 groups.The first group was fed with normal rat chow as the control group, and the subsequent groups were fed with rat chow fortified with 15% weight/weight of the following: fresh palm olein, palm olein heated once, palm olein heated twice, palm olein heated 5 times, or palm olein heated 10 times. The duration of feeding was 6 months. Fatty acid analyses of oil were performed using gas chromatography. Peroxide values were determined using standard titration. Plasma was collected for biochemical analyses.

    RESULTS: Repeatedly heated palm olein increased the levels of peroxide, angiotensin-converting enzyme, and lipid peroxidation as well as reduced the level of heme oxygenase. Fresh palm olein and palm olein heated once had lesser effects on lipid peroxidation and a better effect on the activity of blood pressure-regulating enzymes than repeatedly heated palm olein.

    CONCLUSION: Repeatedly heated palm olein may negatively affect the activity of blood pressure-regulating enzymes and increase lipid peroxidation.

    Matched MeSH terms: Chromatography, Gas
  4. Ismail Z, Mohamed R, Mohd Hassan MH, Wan Su K
    Malays J Med Sci, 2005 Jul;12(2):50-5.
    PMID: 22605958
    The elderly consume many medications including traditional medicines. In 1986, it was found that 29% of elderly took traditional medicines although in 1996, the National Health Morbidity survey reported a 2.3% prevalence. However, studies from other countries showed much higher percentages. The Ministry of Health in Malaysia is concerned that some of these preparations maybe contaminated with steroids, antihistamines, hormones and other poisons. The aims of the study were to determine a). the health seeking behaviour of elderly Malays living in rural areas, b). the utilization of both modern and traditional medicines and c). the steroid content of the traditional medicines used. Methodology included interviews using structured questionnaires of elderly Malays living in rural areas of Kelantan, aged above 60 years. Samples of traditional medications collected were sent to the Pharmacology Department, School of Medical Sciences, Universiti Sains Malaysia, for steroid content analysis using Thin Layer Chromatography. A total of 599 elderly respondents were interviewed comprising 62.4% females and 37.6% males. The 60-69 years cohort group made up 48.7%, followed by 70-79 years at 36.1% and the remainder 15.2% were more than 80 years. There were 82% of elderly taking medicines. The trends of utilization of modern and traditional medicine in the last two weeks among elderly were 59.3% and 40.9% respectively. The utilization of traditional medicine by rural elderly Malays was therefore much higher than that reported in the previous study and nearly similar to that of France and Australian studies. There were 102 samples of traditional medications collected and analysed for steroid content. Results showed that 27.5% were positive for prednisolone, 34.3% positive for unknown steroids (a total of 61.8%) and 38.2% were negative for both steroids. The present study therefore once again confirmed the high usage of traditional medicines where some of which are contaminated with steroids.
    Matched MeSH terms: Chromatography, Thin Layer
  5. Alallam B, Abdulameed HT, Lim V
    Food Chem, 2025 Apr 01;470:142666.
    PMID: 39755036 DOI: 10.1016/j.foodchem.2024.142666
    Sargassum polycystum (S. polycystum) is a brown macroalga with a high phytochemical content, making it a nutritious and bioactive food source. However, information on factors contributing to health benefits, like antioxidants and cytotoxicity, is less explored for Malaysian S. polycystum. In this study, three extracts of S. polycystum were characterized using a combination of analytical techniques. Despite similar carbohydrate content across all extracts, water extract exhibited the highest protein [21.90 ± 1.01 albumin equivalent (μg/mg)] and phenolic [7.73 ± 1.95 gallic acid equivalent (μg/mg)] contents. However, it displayed the lowest antioxidant and anticancer activities [half-maximal inhibitory concentration (IC50) of > 2000 μg/mL]. Interestingly, ethanolic extract demonstrated the strongest scavenging activity (IC50 of 397.90 ± 20.43 μg/mL) and selective anticancer activity against MCF7 breast cancer cells (IC50 of 338.63 ± 48.98 μg/mL). Untargeted metabolomic profiling confirmed the differences in the chemical composition of the extracts. Subsequently, correlation and docking analyses were used to identify the potential bioactive compounds within the extracts. The ethanolic extract is a rich source of these bioactive compounds with superior antioxidant and anticancer properties, highlighting the need for further research on its potential utility in the food industry.
    Matched MeSH terms: Gas Chromatography-Mass Spectrometry
  6. Yusof RM, Haque F, Ismail M, Hassan Z
    Asia Pac J Clin Nutr, 2000 Jun;9(2):130-5.
    PMID: 24394399
    Probiotic organism Bifidobacteria was isolated from the faeces of breast-fed infants at Universiti Putra Malaysia. Trypticase phytone peptone yeast extract agar (TPY) was used as a selective media for the isolation. Morphological examination of the isolates indicated that Bifidobacteria was Gram-positive rods in nature, curved with characteristics of V and Y shapes. The organisms were non-catalase producing, non-nitrate reducing, non-motile, had an absence of indole and were unable to liquify gelatin. The ratios of acetic and lactic acids were determined using high performance liquid chromatography (HPLC). Using carbohydrate fermentation profile test API-CH-50 kits, 20 Bifidobacteria strains had been identified: they were the species of Bifidobacteria infantis and two different sub-species, mainly infantis and lacentis. Based on a wide zone of inhibition, three suitable strains of B. infantis, Bifi-11, Bifi-19 and Bifi-20, were tested in weaning foods for antimicrobial activity towards two human pathogens: E. coli-0157 (World Health Organization) and Salmonella typhimurium S-285. The pH, titratable acidity of weaning foods and total colony count for Bifidobacteria, enteropathogenic Escherichia coli and S. typhimurium were recorded at 3-h intervals for 30 h. It was found that after 9 h of incubation of weaning foods, the pH declined to < 3.6 from pH 6.0, whereas titratable acidity increased from 0.026 to 0.08%. It was indicated that Bifidobacteria inhibited E. coli better than did S typhimurium due to low pH. After 24 h of incubation, approximately 98% of E. coli was inhibited by Bifidobacteria. It is suggested that the inhibitory effect of Bifidobacteria strains in weaning foods towards the growth of enteropathogenic E. coli and S. typhimurium was solely due to low pH and the production of volatile acid components by the organism.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  7. Ariffin N, Newman DW, Nelson MG, O'cualain R, Hubbard SJ
    J Proteome Res, 2024 May 03;23(5):1583-1592.
    PMID: 38651221 DOI: 10.1021/acs.jproteome.3c00675
    MD2 pineapple (Ananas comosus) is the second most important tropical crop that preserves crassulacean acid metabolism (CAM), which has high water-use efficiency and is fast becoming the most consumed fresh fruit worldwide. Despite the significance of environmental efficiency and popularity, until very recently, its genome sequence has not been determined and a high-quality annotated proteome has not been available. Here, we have undertaken a pilot proteogenomic study, analyzing the proteome of MD2 pineapple leaves using liquid chromatography-mass spectrometry (LC-MS/MS), which validates 1781 predicted proteins in the annotated F153 (V3) genome. In addition, a further 603 peptide identifications are found that map exclusively to an independent MD2 transcriptome-derived database but are not found in the standard F153 (V3) annotated proteome. Peptide identifications derived from these MD2 transcripts are also cross-referenced to a more recent and complete MD2 genome annotation, resulting in 402 nonoverlapping peptides, which in turn support 30 high-quality gene candidates novel to both pineapple genomes. Many of the validated F153 (V3) genes are also supported by an independent proteomics data set collected for an ornamental pineapple variety. The contigs and peptides have been mapped to the current F153 genome build and are available as bed files to display a custom gene track on the Ensembl Plants region viewer. These analyses add to the knowledge of experimentally validated pineapple genes and demonstrate the utility of transcript-derived proteomics to discover both novel genes and genetic structure in a plant genome, adding value to its annotation.
    Matched MeSH terms: Chromatography, Liquid
  8. Lau BF, Abdullah N, Aminudin N, Lee HB, Yap KC, Sabaratnam V
    PLoS One, 2014;9(7):e102509.
    PMID: 25054862 DOI: 10.1371/journal.pone.0102509
    Previous studies on the nutritional and nutraceutical properties of Lignosus rhinocerotis focused mainly on the sclerotium; however, the supply of wild sclerotium is limited. In this investigation, the antioxidant capacity and cytotoxic effect of L. rhinocerotis cultured under different conditions of liquid fermentation (shaken and static) were compared to the sclerotium produced by solid-substrate fermentation. Aqueous methanol extracts of the mycelium (LR-MH, LR-MT) and culture broth (LR-BH, LR-BT) demonstrated either higher or comparable antioxidant capacities to the sclerotium extract (LR-SC) based on their radical scavenging abilities, reducing properties, metal chelating activities, and inhibitory effects on lipid peroxidation. All extracts exerted low cytotoxicity (IC50>200 µg/ml, 72 h) against selected mammalian cell lines. Several low-molecular-weight compounds, including sugars, fatty acids, methyl esters, sterols, amides, amino acids, phenolics, and triterpenoids, were identified using GC-MS and UHPLC-ESI-MS/MS. The presence of proteins (<40 kDa) in the extracts was confirmed by SDS-PAGE and SELDI-TOF-MS. Principal component analysis revealed that the chemical profiles of the mycelial extracts under shaken and static conditions were distinct from those of the sclerotium. Results from bioactivity evaluation and chemical profiling showed that L. rhinocerotis from liquid fermentation merits consideration as an alternative source of functional ingredients and potential substitute for the sclerotium.
    Matched MeSH terms: Chromatography, High Pressure Liquid; Gas Chromatography-Mass Spectrometry
  9. Diong SH, Mohd Yusoff NS, Sim MS, Raja Aziddin RE, Chik Z, Rajan P, et al.
    J Anal Toxicol, 2014 Nov-Dec;38(9):660-6.
    PMID: 25106416 DOI: 10.1093/jat/bku096
    Gas chromatography-mass spectrometry quantitative method was developed to monitor concentrations of methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in plasma and urine of patients. The developed method was simple, accurate and reproducible to quantify methadone and EDDP in plasma and urine samples in the concentration range of 15-1,000 and 50-2,000 ng/mL, respectively. The proposed analytical method was applied to plasma and urine samples obtained from 96 patients undergoing methadone maintenance treatment (MMT) with daily methadone doses of 2-120 mg/day. Urinary methadone excretion was observed to be significantly affected by pH, in which the ratio of methadone to EDDP was two times higher in acidic urine (P = 0.029). The findings of this study further enhance the guidelines for monitoring of methadone treatment among outpatients. Methadone-to-EDDP ratio in urine was found to be consistent at 24 and 4 h, hence suggesting the possibility that outpatients may be monitored with single urine sample in order to check for compliance. This study which provides data on peak concentrations of methadone and EDDP as well as the ratio of both compounds has added to the body of knowledge regarding pharmacokinetic properties of methadone among heroin-dependent patients under MMT.
    Study site: University Malaya Medical Centre (UMMC), HKL, University Malaya Centre for Addiction Sciences (UMCAS) and Rehabilitation Centre of Al-Rahman Mosque, Kuala Lumpur, Malaysia
    Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods
  10. Nordin MA, Wan Harun WH, Abdul Razak F, Musa MY
    Int J Oral Sci, 2014 Mar;6(1):15-21.
    PMID: 24406634 DOI: 10.1038/ijos.2013.97
    Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of P. betle was identified using liquid chromatography-mass spectrophotometry (LC-MS/MS). Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments: (i) in the absence of P. betle extract; and in the presence of P. betle extract at respective concentrations of (ii) 1 mg⋅mL(-1); (iii) 3 mg⋅mL(-1); and (iv) 6 mg⋅mL(-1). The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates (µ). Scanning electron microscopy (SEM) was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the µ-values of the treated cells were significantly different than those of the untreated cells (P<0.05), indicating the fungistatic properties of the P. betle extract. The candidal population was also reduced from an average of 13.44×10(6) to 1.78×10(6) viable cell counts (CFU)⋅mL(-1). SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity.
    Matched MeSH terms: Chromatography, Liquid/methods
  11. Wong DZ, Kadir HA, Ling SK
    J Ethnopharmacol, 2012 Jan 6;139(1):256-64.
    PMID: 22107836 DOI: 10.1016/j.jep.2011.11.010
    A parasite plant, Loranthus parasiticus (Loranthaceae), which is generally known as benalu teh (in Malay), Sang Ji Sheng (in Chinese), and baso-kisei (in Japan) distributed in south and southwest part of China, has been used as a folk medicine for the treatment of schizophrenia in southwest China. Loranthus parasiticus has various uses in folk and traditional medicines for bone, brain, kidney, liver, expels wind-damp, and prevents miscarriage.
    Matched MeSH terms: Chromatography, Liquid; Chromatography, Thin Layer
  12. Venkatesh G, Ramanathan S, Mansor SM, Nair NK, Sattar MA, Croft SL, et al.
    J Pharm Biomed Anal, 2007 Mar 12;43(4):1546-51.
    PMID: 17157469
    A simple, sensitive and specific reversed phase high performance liquid chromatographic (RP-HPLC) method with UV detection at 251 nm was developed for simultaneous quantitation of buparvaquone (BPQ), atenolol, propranolol, quinidine and verapamil. The method was applicable in rat in situ intestinal permeability study to assess intestinal permeability of BPQ, a promising lead compound for Leishmania donovani infections. The method was validated on a C-4 column with mobile phase comprising ammonium acetate buffer (0.02 M, pH 3.5) and acetonitrile in the ratio of 30:70 (v/v) at a flow rate of 1.0 ml/min. The retention times for atenolol, quinidine, propranolol, verapamil and BPQ were 4.30, 5.96, 6.55, 7.98 and 8.54 min, respectively. The calibration curves were linear (correlation coefficient > or =0.996) in the selected range of each analyte. The method is specific and sensitive with limit of quantitation of 15 microg/ml for atenolol, 0.8 microg/ml for quinidine, 5 microg/ml for propranolol, 10 microg/ml for verapamil and 200 ng/ml for BPQ. The validated method was found to be accurate and precise in the working calibration range. Stability studies were carried out at different storage conditions and all the analytes were found to be stable. This method is simple, reliable and can be routinely used for accurate permeability characterization.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
  13. Mohamed SIA, Jantan I, Nafiah MA, Seyed MA, Chan KM
    Curr Pharm Biotechnol, 2021;22(2):262-273.
    PMID: 32532192 DOI: 10.2174/1389201021666200612173029
    BACKGROUND: The anticancer effects of Phyllanthus amarus extract on various cancer cells have been investigated, however, the effects of its major constituents on HCT116 human colorectal cancer cells have not been reported.

    OBJECTIVE: In the present study, we investigated the cytotoxic effect of 80% ethanol extract of P. amarus and its marker constituents (phyllanthin, hypophyllanthin, gallic acid, niranthin, greraniin, phyltetralin, isolintetralin, corilagin and ellagic acid) on HCT116 and their underlying mechanisms of action.

    METHODS: Their antiproliferative and apoptotic effects on HCT 116 were performed using MTT assay and flow cytometric analysis, respectively, while caspases 3/7, 8 and 9 activities were examined using the colorimetric method. The expression of cleaved poly ADP ribose polymerase enzyme (PARP) and cytochrome c proteins was investigated by the immune-blot technique.

    RESULTS AND DISCUSSION: HPLC and LC-MS/MS analyses demonstrated that the extract contained mainly lignans and polyphenols. The plant samples markedly suppressed the growth and expansion of HCT116 cells in a concentration- and time-dependent manner with no toxicity against normal human fibroblast CCD18 Co. P. amarus extract, phyllanthin and gallic acid induced mode of cell death primarily through apoptosis as confirmed by the exteriorization of phosphatidylserine. Caspases 3/7, 8, and 9 activities increased in a concentration-dependent manner following 24h treatment. The expressions of cleaved PARP (Asp 214) and cytochrome c were markedly upregulated.

    CONCLUSION: P. amarus extract, phyllanthin and gallic acid exhibited an apoptotic effect on HCT116 cells through the caspases-dependent pathway.

    Matched MeSH terms: Chromatography, Liquid/methods
  14. Hariono M, Rollando R, Karamoy J, Hariyono P, Atmono M, Djohan M, et al.
    Molecules, 2020 Oct 14;25(20).
    PMID: 33066411 DOI: 10.3390/molecules25204691
    Matrix metalloproteinase9 (MMP9) is known to be highly expressed during metastatic cancer where most known potential inhibitors failed in the clinical trials. This study aims to select local plants in our state, as anti-breast cancer agent with hemopexin-like domain of MMP9 (PEX9) as the selective protein target. In silico screening for PEX9 inhibitors was performed from our in house-natural compound database to identify the plants. The selected plants were extracted using methanol and then a step-by-step in vitro screening against MMP9 was performed from its crude extract, partitions until fractions using FRET-based assay. The partitions were obtained by performing liquid-liquid extraction on the methanol extract using n-hexane, ethylacetate, n-butanol, and water representing nonpolar to polar solvents. The fractions were made from the selected partition, which demonstrated the best inhibition percentage toward MMP9, using column chromatography. Of the 200 compounds screened, 20 compounds that scored the binding affinity -11.2 to -8.1 kcal/mol toward PEX9 were selected as top hits. The binding of these hits were thoroughly investigated and linked to the plants which they were reported to be isolated from. Six of the eight crude extracts demonstrated inhibition toward MMP9 with the IC50 24 to 823 µg/mL. The partitions (1 mg/mL) of Ageratum conyzoides aerial parts and Ixora coccinea leaves showed inhibition 94% and 96%, whereas their fractions showed IC50 43 and 116 µg/mL, respectively toward MMP9. Using MTT assay, the crude extract of Ageratum exhibited IC50 22 and 229 µg/mL against 4T1 and T47D cell proliferations, respectively with a high safety index concluding its potential anti-breast cancer from herbal.
    Matched MeSH terms: Chromatography, Thin Layer; Gas Chromatography-Mass Spectrometry
  15. Teh CH, Nazni WA, Nurulhusna AH, Norazah A, Lee HL
    BMC Microbiol, 2017 Feb 16;17(1):36.
    PMID: 28209130 DOI: 10.1186/s12866-017-0936-3
    BACKGROUND: Antimicrobial resistance is currently a major global issue. As the rate of emergence of antimicrobial resistance has superseded the rate of discovery and introduction of new effective drugs, the medical arsenal now is experiencing shortage of effective drugs to combat diseases, particularly against diseases caused by the dreadful multidrug-resistant strains, such as the methicillin-resistant Staphylococcus aureus (MRSA). The ability of fly larvae to thrive in septic habitats has prompted us to determine the antibacterial activity and minimum inhibitory concentrations (MICs) of larval extract of flies, namely Lucilia cuprina, Sarcophaga peregrina and Musca domestica against 4 pathogenic bacteria [Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Pseudomonas aeruginosa and Escherichia coli] via a simple and sensitive antibacterial assay, resazurin-based turbidometric (TB) assay as well as to demonstrate the preliminary chemical profile of larval extracts using gas chromatography-mass spectrophotometry (GC-MS).

    RESULTS: The resazurin-based TB assay demonstrated that the L. cuprina larval extract was inhibitory against all tested bacteria, whilst the larval extract of S. peregrina and M. domestica were only inhibitory against the MRSA, with a MIC of 100 mg ml(-1). Subsequent sub-culture of aliquots revealed that the larval extract of L. cuprina was bactericidal against MRSA whilst the larval extracts of S. peregrina and M. domestica were bacteriostatic against MRSA. The GC-MS analysis had quantitatively identified 20 organic compounds (fatty acids or their derivatives, aromatic acid esters, glycosides and phenol) from the larval extract of L. cuprina; and 5 fatty acid derivatives with known antimicrobial activities from S. peregrina and M. domestica.

    CONCLUSION: The resazurin-based turbidometric assay is a simple, reliable and feasible screening assay which evidently demonstrated the antibacterial activity of all fly larval extracts, primarily against the MRSA. The larval extract of L. cuprina exerted a broad spectrum antibacterial activity against all tested bacteria. The present study revealed probable development and use of novel and effective natural disinfectant(s) and antibacterial agent(s) from flies and efforts to screen more fly species for antibacterial activity using resazurin-based TB assay should be undertaken for initial screening for subsequent discovery and isolation of potential novel antimicrobial substances, particularly against the multi-drug resistant strains.

    Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods
  16. Tan CH, Tan KY, Yap MK, Tan NH
    Sci Rep, 2017 02 27;7:43237.
    PMID: 28240232 DOI: 10.1038/srep43237
    Tropidolaemus wagleri (temple pit viper) is a medically important snake in Southeast Asia. It displays distinct sexual dimorphism and prey specificity, however its venomics and inter-sex venom variation have not been thoroughly investigated. Applying reverse-phase HPLC, we demonstrated that the venom profiles were not significantly affected by sex and geographical locality (Peninsular Malaya, insular Penang, insular Sumatra) of the snakes. Essentially, venoms of both sexes share comparable intravenous median lethal dose (LD50) (0.56-0.63 μg/g) and cause neurotoxic envenomation in mice. LCMS/MS identified six waglerin forms as the predominant lethal principles, comprising 38.2% of total venom proteins. Fourteen other toxin-protein families identified include phospholipase A2, serine proteinase, snaclec and metalloproteinase. In mice, HPLC fractions containing these proteins showed insignificant contribution to the overall venom lethality. Besides, the unique elution pattern of approximately 34.5% of non-lethal, low molecular mass proteins (3-5 kDa) on HPLC could be potential biomarker for this primitive crotalid species. Together, the study unveiled the venom proteome of T. wagleri that is atypical among many pit vipers as it comprises abundant neurotoxic peptides (waglerins) but little hemotoxic proteinases. The findings also revealed that the venom is relatively well conserved intraspecifically despite the drastic morphological differences between sexes.
    Matched MeSH terms: Chromatography, High Pressure Liquid; Chromatography, Reverse-Phase
  17. Khoo LW, Kow ASF, Maulidiani M, Ang MY, Chew WY, Lee MT, et al.
    Phytochem Anal, 2019 Jan;30(1):46-61.
    PMID: 30183131 DOI: 10.1002/pca.2789
    INTRODUCTION: Clinacanthus nutans, a small shrub that is native to Southeast Asia, is commonly used in traditional herbal medicine and as a food source. Its anti-inflammation properties is influenced by the metabolites composition, which can be determined by different binary extraction solvent ratio and extraction methods used during plant post-harvesting stage.

    OBJECTIVE: Evaluate the relationship between the chemical composition of C. nutans and its anti-inflammatory properties using nuclear magnetic resonance (NMR) metabolomics approach.

    METHODOLOGY: The anti-inflammatory effect of C. nutans air-dried leaves extracted using five different binary extraction solvent ratio and two extraction methods was determined based on their nitric oxide (NO) inhibition effect in lipopolysaccharide-interferon-gamma (LPS-IFN-γ) activated RAW 264.7 macrophages. The relationship between extract bioactivity and metabolite profiles and quantifications were established using 1 H-NMR metabolomics and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The possible metabolite biosynthesis pathway was constructed to further strengthen the findings.

    RESULTS: Water and sonication prepared air-dried leaves possessed the highest NO inhibition activity (IC50  = 190.43 ± 12.26 μg/mL, P 

    Matched MeSH terms: Chromatography, Liquid/methods
  18. Baharudin MMA, Ngalimat MS, Mohd Shariff F, Balia Yusof ZN, Karim M, Baharum SN, et al.
    PLoS One, 2021;16(5):e0251514.
    PMID: 33974665 DOI: 10.1371/journal.pone.0251514
    Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have reached epidemic proportions globally. Therefore, there is an urgent need for a continuous supply of antibiotics to combat the problem. In this study, bacteria initially identified as species belonging to the Bacillus amyloliquefaciens operational group were re-identified based on the housekeeping gene, gyrB. Cell-free supernatants (CFS) from the strains were used for antimicrobial tests using the agar well diffusion assay against MRSA and various types of pathogenic bacteria. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and physicochemical characteristics of the CFS were determined. Based on gyrB sequence analysis, five strains (PD9, B7, PU1, BP1 and L9) were identified as Bacillus velezensis. The CFS of all B. velezensis strains showed broad inhibitory activities against Gram-negative and -positive as well as MRSA strains. Strain PD9 against MRSA ATCC 33742 was chosen for further analysis as it showed the biggest zone of inhibition (21.0 ± 0.4 mm). The MIC and MBC values obtained were 125 μl/ml. The crude antimicrobial extract showed bactericidal activity and was stable at various temperatures (40-80°C), pH (4-12), surfactants (Tween 20, Tween 80, SDS and Triton X-100) and metal ions (MgCI2, NaCI2, ZnNO3 and CuSO4) when tested. However, the crude extract was not stable when treated with proteinase K. All these properties resembled the characteristics of peptides. The antimicrobial compound from the selected strain was purified by using solvent extraction method and silica gel column chromatography. The purified compound was subjected to High Performance Liquid Chromatography which resulted in a single peak of the anti-MRSA compound being detected. The molecular weight of the anti-MRSA compound was determined by using SDS-PAGE and zymogram. The size of the purified antimicrobial peptide was approximately ~ 5 kDa. The antimicrobial peptide produced from B. velezensis strain PD9 is a promising alternative to combat the spread of MRSA infections in the future.
    Matched MeSH terms: Chromatography, Gel; Chromatography, High Pressure Liquid
  19. Hakkimane SS, Shenoy VP, Gaonkar SL, Bairy I, Guru BR
    Int J Nanomedicine, 2018;13:4303-4318.
    PMID: 30087562 DOI: 10.2147/IJN.S163925
    INTRODUCTION: Tuberculosis (TB) is the single largest infectious disease which requires a prolonged treatment regime with multiple drugs. The present treatment for TB includes frequent administration of a combination of four drugs for a duration of 6 months. This leads to patient's noncompliance, in addition to developing drug-resistant strains which makes treatment more difficult. The formulation of drugs with biodegradable polymeric nanoparticles (NPs) promises to overcome this problem.

    MATERIALS AND METHODS: In this study, we focus on two important drugs used for TB treatment - rifampicin (RIF) and isoniazid (INH) - and report a detailed study of RIF-loaded poly lactic-co-glycolic acid (PLGA) NPs and INH modified as INH benz-hydrazone (IH2) which gives the same therapeutic effect as INH but is more stable and enhances the drug loading in PLGA NPs by 15-fold compared to INH. The optimized formulation was characterized using particle size analyzer, scanning electron microscopy and transmission electron microscopy. The drug release from NPs and stability of drug were tested in different pH conditions.

    RESULTS: It was found that RIF and IH2 loaded in NPs release in a slow and sustained manner over a period of 1 month and they are more stable in NPs formulation compared to the free form. RIF- and IH2-loaded NPs were tested for antimicrobial susceptibility against Mycobacterium tuberculosis H37Rv strain. RIF loaded in PLGA NPs consistently inhibited the growth at 70% of the minimum inhibitory concentration (MIC) of pure RIF (MIC level 1 µg/mL), and pure IH2 and IH2-loaded NPs showed inhibition at MIC equivalent to the MIC of INH (0.1 µg/mL).

    CONCLUSION: These results show that NP formulations will improve the efficacy of drug delivery for TB treatment.

    Matched MeSH terms: Chromatography, High Pressure Liquid; Chromatography, Reverse-Phase
  20. Syahidah A, Saad CR, Hassan MD, Rukayadi Y, Norazian MH, Kamarudin MS
    Pak J Biol Sci, 2017;20(2):70-81.
    PMID: 29022997 DOI: 10.3923/pjbs.2017.70.81
    BACKGROUND AND OBJECTIVE: The problems of bacterial diseases in aquaculture are primarily controlled by antibiotics. Medicinal plants and herbs which are seemed to be candidates of replacements for conventional antibiotics have therefore gained increasing interest. Current study was performed to investigate the presence of phytochemical constituents, antibacterial activities and composition of antibacterial active compounds in methanolic extract of local herb, Piper betle .

    METHODOLOGY: Qualitative phytochemical analysis was firstly carried out to determine the possible active compounds in P. betle leaves methanolic extract. The antibacterial activities of major compounds from this extract against nine fish pathogenic bacteria were then assessed using TLC-bioautography agar overlay assay and their quantity were determined simultaneously by HPLC method.

    RESULTS: The use of methanol has proved to be successful in extracting numerous bioactive compounds including antibacterial compounds. The TLC-bioautography assay revealed the inhibitory action of two compounds which were identified as hydroxychavicol and eugenol. The $-caryophyllene however was totally inactive against all the tested bacterial species. In this study, the concentration of hydroxychavicol in extract was found to be 374.72±2.79 mg g-1, while eugenol was 49.67±0.16 mg g-1.

    CONCLUSION: Based on these findings, it could be concluded that hydroxychavicol and eugenol were the responsible compounds for the promising antibacterial activity of P. betle leaves methanolic extract. This inhibitory action has significantly correlated with the amount of the compounds in extract. Due to its potential, the extract of P. betle leaves or it compounds can be alternative source of potent natural antibacterial agents for aquaculture disease management.

    Matched MeSH terms: Chromatography, High Pressure Liquid; Chromatography, Thin Layer
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