Displaying publications 741 - 760 of 1723 in total

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  1. Tin, H.S., Padam, B.S., Abdullah, M.I., Chye, F.Y.
    MyJurnal
    The study aimed to isolate and elucidate the chemical compounds that are found in banana
    (Musa balbisiana cv. Saba) inflorescences. Banana inflorescence buds were extracted using
    methanol and the resulted methanolic extract was partitioned using chloroform, ethyl acetate
    and butanol against deionized water. The chloroform partition was further separated into
    fractions using column chromatography assisted by thin layer chromatography. The structure
    elucidation was performed using nuclear magnetic resonance spectrometry (NMR). Three
    triterpenes were isolated namely 31-norcyclolaudenone (1), cycloartenol (2) and (24R)-4a,24-
    trimethyl-5a-cholesta-8,25(27)-dien-3b-ol (3). This is the first report on the isolation of these
    triterpenes from Musa balbisiana inflorescence. The discovery of new triterpenes from banana
    inflorescence should be further explored to open a new perspective that banana by-products
    might serve as new source of natural products for food and pharmaceutical applications.
    Matched MeSH terms: Chromatography, Thin Layer
  2. Ahmed Kaid, N. A., Norbaiyah, M. B., Imad, M. A., Norazian, M. H.
    MyJurnal
    Introduction: This study aims to build a standardization method for preparation of effective powder from
    FSA and to quantify diosgenin in FSA. Methodology: One kg of FS were used in this study. Setting: BMS, KOM
    and KOP, IIUM Kuantan campus. FS were washed with distilled water to exclude any foreign matter, and
    were then air dried. FS-powder were put in distilled water in a ratio of 1 g of powder in 20 ml of distilled
    water and were shaken at room temperature for 24 hours. Ten mg of hydrolyzed extract sample was diluted
    in 10 ml volumetric flask with methanol for 15 minutes. Chromatographic estimation was performed using
    an equilibrated reverse phase Eclipse XDB-C18 column (particle size 5 µg, 4.6 mm x 150 mm). Results: One
    gram of FSA extract was hydrolyzed to produce sapogenins and 46.6% was recovered. A calibration curve
    that was constructed based on five dilutions of diosgenin standard at concentrations of 2, 5, 10, 20, 30 and
    50 ppm produced a linear graft (r = 0.999). The concentration of diosgenin in FSA extract as calculated using
    the regression analysis was found to be 29.66 µg/ml, 13.81 % w/w on dried weight basis. Conclusion:
    Preparation and standardization of effective powder from FSA are the corner stone of many scientific
    researches in IIUM and Malaysia. Diosgenin is available in the FSA in adequate concentration. The adequate
    amount of diosgenin in the FSA will guide us to do further study in the way of preparation of a natural
    product that can be used in the field of reversible anti-fertility therapy.
    Matched MeSH terms: Chromatography
  3. Abdullah R, Diaz LN, Wesseling S, Rietjens IM
    PMID: 27892830 DOI: 10.1080/19440049.2016.1266098
    After the incidences of induction of aristolochic acid nephropathy after consumption of herbal weight loss preparations that accidentally contained aristolochic acids (AAs), several countries defined national restrictions on the presence of AAs in food, including plant food supplements (PFS) and herbal products. This study investigates whether the risks associated with exposure to AAs via PFS and herbal products are at present indeed negligible. Data reported in literature on AA levels in PFS and other herbal products and also obtained from a new series of PFS in the present study were used to calculate the estimated daily intakes (EDIs) and corresponding margins of exposure (MOEs). Available literature data revealed that 206 out of 573 samples were found to contain aristolochic acid I (AAI) and/or aristolochic acid II (AAII). The results obtained from recently collected PFS revealed that both AAI and AAII were detected in three out of 18 analysed PFS at levels up to 594.8 and 235.3 µg g(-1), respectively, being in line with the levels reported in literature. The EDIs resulting from intake of these PFS resulted in MOEs that were generally below 10,000, corroborating the priority for risk management. Although these results refer to PFS collected by targeted sampling strategies, the data reveal that AA-containing PFS are still freely available. When considering that the use of these samples may be limited to shorter periods of time, the EDIs might be lower, but MOE values would still be lower than 10,000 for more than 50% of the AA-containing PFS and herbal products. In conclusion, the presence of AAs in PFS and herbal products even several years after instalment of the legal restrictions still raises concern, especially for people who frequently use the respective PFS and herbal products.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  4. Bivi MS, Paiko AS, Khairulmazmi A, Akhtar MS, Idris AS
    Plant Pathol J, 2016 Oct;32(5):396-406.
    PMID: 27721689
    Continuous supplementation of mineral nutrients and salicylic acid (SA) as foliar application could improve efficacy in controlling basal stem rot (BSR) disease in oil palm seedling. It is revealed from the results that the highest disease severity index (58.3%) was recorded in T8 treatments at 9 months after inoculation. The best disease control was achieved by T7 treatments (calcium/copper/SA [Ca/Cu/SA]) (5.0%) followed by T1 (5.5%), T5 (5.8%), T3 (8.3%), T6 (8.3%), T4 (13.3%), and T2 (15.8%) treatments. Continuous supplementation of Ca/Cu/SA was found to be the most effective in controlling the disease and the high performance liquid chromatography results showed the detection of ergosterol at very low concentration in the treated samples. Moreover, the transmission electron microscopy analysis results clearly indicated that T7 treatment was also enhancing lignification, which was responsible for the thickness of the secondary cell walls and middle lamella compared to untreated samples. It was therefore, concluded that continuous supplementation of minerals nutrients and SA could effectively suppress disease severity by reducing ergosterol activity and also improve the process of lignification in the treated plants. Furthermore, this treatment also managed to delay the onset of BSR symptoms and promote the growth of the seedlings and eventually suppress the BSR disease.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  5. Nurdianah, H.F., Ahmad Firdaus, A.H., Eshaifol Azam, O., Wan Adnan, W.O.
    MyJurnal
    Bee pollen is considered as one of the functional foods due to its complex biochemical
    properties. Bee pollen which is collected from pollen grains from various botanical sources
    contains almost a complete nutrition such as carbohydrates, proteins, amino acids, vitamins
    and minerals. Its beneficial effect on health is thought to be due to the presence of phenolic
    compounds with its antioxidant activity. Antioxidant activities of ethanolic bee pollen extract
    (BPE) from three species of Malaysian stingless bee; Trigona thoracica, Trigona itama and
    Trigona apicalis in this study were measured using DPPH-HPLC method and gallic acid (GA)
    as a standard reference. The percentage of DPPH inhibition by T. apicalis BPE at 1 mg/mL
    showed the highest inhibition (39%, GA equivalent to 0.3 mg/mL) compared with T. itama
    (14.3%, GA equivalent to 0.1 mg/mL) and T. thoracica (6.7%, GA equivalent to 0.05 mg/mL).
    Our result was the first in reporting antioxidant activity of BPE measured using DPPH-HPLC
    method from three different species of Malaysian stingless bee.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  6. Ugusman A, Zakaria Z, Hui CK, Nordin NA, Mahdy ZA
    EXCLI J, 2012;11:705-714.
    PMID: 27847456
    Abnormalities in endothelial cell structure and function may lead to diseases such as thrombosis and atherosclerosis. Oxidative stress plays an important role in the pathogenesis of various cardiovascular diseases including atherosclerosis. Previous studies have shown a relationship between a diet rich in flavonoid and a reduced incidence of cardiovascular diseases. Piper sarmentosum (PS) is a plant with high flavonoid content and it possesses antioxidant and anti-atherosclerotic activities. Therefore this study aimed to investigate the flavonoids present in aqueous extract of PS (AEPS) and its cytoprotective effects in oxidative stress-induced human umbilical vein endothelial cells (HUVEC). AEPS contained high total phenolic content (91.02 ± 0.02 mg QE/g DM) and total flavonoid content (48.57 ± 0.03 mg GAE/g DM). Screening using high performance liquid chromatography (HPLC) technique showed the presence of rutin and vitexin as the main flavonoids in AEPS. HUVEC were exposed to 180 µM H2O2 and treated with various concentrations of rutin or vitexin (10 to 400 µM) for 24 hours. Both rutin and vitexin at the concentration of 150-400 µM significantly increased the viability of H2O2-induced HUVEC as denoted by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Therefore rutin and vitexin as the main flavonoids present in PS may be involved in the protective effects of PS against oxidative stress.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  7. Chang CC, Saad B, Surif M, Ahmad MN, Md Shakaff AY
    Sensors (Basel), 2008 Jun 01;8(6):3665-3677.
    PMID: 27879900
    A disposable screen-printed e-tongue based on sensor array and pattern recognition that is suitable for the assessment of water quality in fish tanks is described. The characteristics of sensors fabricated using two kinds of sensing materials, namely (i) lipids (referred to as Type 1), and (ii) alternative electroactive materials comprising liquid ion-exchangers and macrocyclic compounds (Type 2) were evaluated for their performance stability, sensitivity and reproducibility. The Type 2 e-tongue was found to have better sensing performance in terms of sensitivity and reproducibility and was thus used for application studies. By using a pattern recognition tool i.e. principal component analysis (PCA), the e-tongue was able to discriminate the changes in the water quality in tilapia and catfish tanks monitored over eight days. E-tongues coupled with partial least squares (PLS) was used for the quantitative analysis of nitrate and ammonium ions in catfish tank water and good agreement were found with the ion-chromatography method (relative error, ±1.04- 4.10 %).
    Matched MeSH terms: Chromatography
  8. Loh KS, Lee YH, Musa A, Salmah AA, Zamri I
    Sensors (Basel), 2008 Sep 18;8(9):5775-5791.
    PMID: 27873839
    Magnetic nanoparticles of Fe₃O₄ were synthesized and characterized using transmission electron microscopy and X-ray diffraction. The Fe₃O₄ nanoparticles were found to have an average diameter of 5.48 ±1.37 nm. An electrochemical biosensor based on immobilized alkaline phosphatase (ALP) and Fe₃O₄ nanoparticles was studied. The amperometric biosensor was based on the reaction of ALP with the substrate ascorbic acid 2-phosphate (AA2P). The incorporation of the Fe₃O₄ nanoparticles together with ALP into a sol gel/chitosan biosensor membrane has led to the enhancement of the biosensor response, with an improved linear response range to the substrate AA2P (5-120 μM) and increased sensitivity. Using the inhibition property of the ALP, the biosensor was applied to the determination of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The use of Fe₃O₄ nanoparticles gives a two-fold improvement in the sensitivity towards 2,4-D, with a linear response range of 0.5-30 μgL-1. Exposure of the biosensor to other toxicants such as heavy metals demonstrated only slight interference from metals such as Hg2+, Cu2+, Ag2+ and Pb2+. The biosensor was shown to be useful for the determination of the herbicide 2, 4-D because good recovery of 95-100 percent was obtained, even though the analysis was performed in water samples with a complex matrix. Furthermore, the results from the analysis of 2,4-D in water samples using the biosensor correlated well with a HPLC method.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  9. Mohd Hassan FW, Muggundha Raoov, Kamaruzaman S, Sanagi MM, Yoshida N, Hirota Y, et al.
    J Sep Sci, 2018 Oct;41(19):3751-3763.
    PMID: 30125466 DOI: 10.1002/jssc.201800326
    This study describes a dispersive liquid-liquid microextraction combined with dispersive solid-phase extraction method based on phenyl-functionalized magnetic sorbent for the preconcentration of polycyclic aromatic hydrocarbons from environmental water, sugarcane juice, and tea samples prior to gas chromatography with mass spectrometry analysis. Several important parameters affecting the extraction efficiency were investigated thoroughly, including the mass of sorbent, type and volume of extraction solvent, extraction time, type of desorption solvent, desorption time, type and amount of salt-induced demulsifier, and sample volume. Under the optimized extraction and gas chromatography-mass spectrometric conditions, the method revealed good linearity (10-100000 ng/L) with coefficient of determination (R2 ) of ≥0.9951, low limits of detection (3-16 ng/L), high enrichment factors (61-239), and satisfactory analyte recoveries (86.3-109.1%) with the relative standard deviations 
    Matched MeSH terms: Gas Chromatography-Mass Spectrometry
  10. Siti Fadhilah Abd. Rahim, Normala Masrom, Muhamad Cyrill Kamal, Noor Azmi Shaharuddin, Khairul Basyar Baharudin, Norliza Abu Bakar
    MyJurnal
    Water contamination by herbicides and chelating agents is increasing mainly due to the
    increasing agricultural activities. Water contamination by these compounds has become a
    concern due to their adverse effects to the environment and humans. Seven sampling sites of
    water sources in Selangor and Johor were chosen for the study. Contamination level of
    Mecoprop (MCCP), Nitrilotriacetic acid (NTA) and Ethylenediaminetetraacetic acid (EDTA) in
    these water body areas was determined by using Gas Chromatography-Electron Capture
    Detector (GC-ECD). Our results indicated that water samples of Sungai Melot in Selangor
    showed the highest presence of EDTA. MCCP was detected at a high level at Sungai Sarang
    Buaya, Johor while NTA showed similar level of concentration at three different sites, Ladang
    10, Ladang Sayur and Mardi, Selangor.
    Matched MeSH terms: Chromatography, Gas
  11. Panettieri S, Gjinaj E, John G, Lohman DJ
    PLoS One, 2018;13(9):e0202465.
    PMID: 30208047 DOI: 10.1371/journal.pone.0202465
    With varied, brightly patterned wings, butterflies have been the focus of much work on the evolution and development of phenotypic novelty. However, the chemical structures of wing pigments from few butterfly species have been identified. We characterized the orange wing pigments of female Elymnias hypermnestra butterflies (Lepidoptera: Nymphalidae: Satyrinae) from two Southeast Asian populations. This species is a sexually dimorphic Batesian mimic of several model species. Females are polymorphic: in some populations, females are dark, resemble conspecific males, and mimic Euploea spp. In other populations, females differ from males and mimic orange Danaus spp. Using LC-MS/MS, we identified nine ommochrome pigments: six from a population in Chiang Mai, Thailand, and five compounds from a population in Bali, Indonesia. Two ommochromes were found in both populations, and only two of the nine compounds have been previously reported. The sexually dimorphic Thai and Balinese populations are separated spatially by monomorphic populations in peninsular Malaysia, Singapore, and Sumatra, suggesting independent evolution of mimetic female wing pigments in these disjunct populations. These results indicate that other butterfly wing pigments remain to be discovered.
    Matched MeSH terms: Chromatography, Liquid
  12. Keshavarzifard, Mehrzad, Mohamad Pauzi Zakaria, Keshavarzifard, Shahin, Sharifi, Reza
    MyJurnal
    This study investigated distributions, composition patterns, sources and potential toxicity of polycyclic aromatic hydrocarbon (PAHs) pollution in surface sediments from the Kim Kim River and Segget River, Peninsular Malaysia. The samples were extracted using Soxhlet extraction, purified using two-step silica gel column chromatography and then analysed by gas chromatography mass spectrometry (GC-MS). The total PAH concentrations ranged from 95.17 to 361.24 ng g-1 dry weight (dw) and 330.09 to 552.76 ng g-1 dw in surface sediments from the Kim Kim and Segget Rivers, respectively. Source type identification using PAH molecular indices and hierarchical cluster analysis (HCA) indicated that PAHs were mostly of pyrogenic origin, while in some stations petrogenic sources had a significant portion. A PAH toxicity assessment using sediment quality guidelines (SQGs), mean effect range-median quotient (M-ERM-Q), benzo[a]pyrene (BaP) equivalent concentration and BaP toxicity equivalent quotient (TEQcarc) indicated low probability of toxicity for both the Kim Kim and Segget Rivers. Moreover, the human health risk assessment applying Cancer Riskingestion and Cancer Riskdermal indicated that probabilistic health risk to humans via ingestion and dermal pathways from sediments of the Kim Kim and Segget Rivers can be categorised as low-to-moderate risk.
    Matched MeSH terms: Gas Chromatography-Mass Spectrometry
  13. Jamil NAM, Rahmad N, Rosli NHM, Al-Obaidi JR
    Electrophoresis, 2018 12;39(23):2954-2964.
    PMID: 30074628 DOI: 10.1002/elps.201800185
    Wax apple is one of the underutilized fruits that is considered a good source of fibers, vitamins, minerals as well as antioxidants. In this study, a comparative analysis of the developments of wax fruit ripening at the proteomic and metabolomic level was reported. 2D electrophoresis coupled with MALDI-TOF/TOF was used to compare the proteome profile from three developmental stages named immature, young, and mature fruits. In general, the protein expression profile and the identified proteins function were discussed for their potential roles in fruit physiological development and ripening processes. The metabolomic investigation was also performed on the same samples using quadrupole LC-MS (LC-QTOF/MS). Roles of some of the differentially expressed proteins and metabolites are discussed in relation to wax apple ripening during the development. This is the first study investigating the changes in the proteins and metabolites in wax apple at different developmental stages. The information obtained from this research will be helpful in developing biomarkers for breeders and help the plant researchers to avoid wax apple cultivation problems such as fruit cracking.
    Matched MeSH terms: Chromatography, Liquid
  14. Osman BE, Khalik WMAWM
    Data Brief, 2018 Oct;20:999-1003.
    PMID: 30225314 DOI: 10.1016/j.dib.2018.08.178
    The main goal of this research work is to measure the concentration levels of organochlorine residue in soil. The potential health risk of this pollutant on human was also determined. 10 samples were taken from a lowland paddy field situated in Kelantan, Malaysia. Physical parameters namely soil pH, organic carbon content, water content and particle size were identified to evaluate the quality of soil from the agriculture site. Soxhlet extraction and florisil clean-up process were applied to isolate 10 targeted organochlorine compounds prior to the final determination using a gas chromatography-electron capture detector. Soil from the lowland has characteristics such as slightly acidic, low organic carbon content, high water content and texture dominated by the sandy type. Concentration levels of six detected organochlorine pesticides were calculated in µg/kg. Hazard quotient value in all samples was less than the acceptable risk level HQ ≤ 1, thus reflecting the status of soil in the subjected area as unlikely to pose any adverse health effects.
    Matched MeSH terms: Chromatography, Gas
  15. Meriam Suhaimy SH, Lai CW, Tajuddin HA, Samsudin EM, Johan MR
    Materials (Basel), 2018 Oct 23;11(11).
    PMID: 30360462 DOI: 10.3390/ma11112066
    There are various approaches to enhancing the catalytic properties of TiO₂, including modifying its morphology by altering the surface reactivity and surface area of the catalyst. In this study, the primary aim is to enhance the photocatalytic activity by changing the TiO₂ nanotubes' architecture. The highly ordered infrastructure is favorable for a better charge carrier transfer. It is well known that anodization affects TiO₂ nanotubes' structure by increasing the anodization duration which in turn influence the photocatalytic activity. The characterizations were conducted by FE-SEM (fiend emission scanning electron microscopy), XRD (X-ray diffraction), RAMAN (Raman spectroscopy), EDX (Energy dispersive X-ray spectroscopy), UV-Vis (Ultraviolet visible spectroscopy) and LCMS/MS/MS (liquid chromatography mass spectroscopy). We found that the morphological structure is affected by the anodization duration according to FE-SEM. The photocatalytic degradation shows a photodegradation rate of k = 0.0104 min-1. It is also found that a mineralization of Simazine by our prepared TiO₂ nanotubes leads to the formation of cyanuric acid. We propose three Simazine photodegradation pathways with several intermediates identified.
    Matched MeSH terms: Chromatography, Liquid
  16. Mohammad Rashedi Ismail-Fitry, Safiullah Jauhar, Chong, Gun Hean, Mahmud Ab Rashid NorKhaizura, Wan Zunairah Wan Ibadullah
    MyJurnal
    Recently natural polyphenol compounds (PCs) of plants, gained wide consideration of
    scientists, companies and public people because of its unique pharmaceutical and
    preservative benefits in the physiological system. They can prevent mortal and serious
    diseases such as cancer, cardiovascular and Alzheimer. However, defining a suitable
    source of PCs and their proper, economic and efficient extraction method are still a
    challenge. The aim of this study was to review PCs as an important antioxidant, the
    significance of pomegranate as a source of natural PCs and its application in meat and
    meat product. This study also covers different types of PCs extraction methods such as
    solid-liquid extraction (SLE) method as a conventional extraction which using Soxhlet
    apparatus and several solvents and advanced methods such as microwave-assisted
    extraction (MAE), supercritical fluid extraction (SFE), accelerated solvent extraction
    (ASE), ultrasound-assisted extraction (UAE) and high hydrostatic pressure extraction
    (HHPE). Simple and developed analytical method of PCs is also reviewed in the study.
    SLE method is an easy and simple method but, it uses lots of chemicals and is not
    suitable for all kinds of PCs extraction. UAE is using for quick extraction PCs, SFE is green
    extraction method uses less solvent and have a good result but it needs high
    technology. ASE method is a proper alternative for Soxhlet extraction method for its
    quick result. MAE method has high extraction result but is not suitable for some
    thermolabile PCs. Several parts of pomegranate showed antioxidant and antimicrobial
    traits for shelf life extension of meat and meat product. Pomegranate peel is the
    strongest antioxidant followed by pomegranate juice and seed. Pomegranate peel
    prolonged chilled chicken meat shelf live up to three weeks.
    Matched MeSH terms: Chromatography, Supercritical Fluid
  17. Liang JL, Yeow CC, Teo KC, Gnanaraj C, Chang YP
    J Food Sci Technol, 2019 Oct;56(10):4696-4704.
    PMID: 31686701 DOI: 10.1007/s13197-019-03912-5
    The capsicum seed core and cabbage outer leaves are common wastes generated in the vegetable processing industry. We explored the in vitro health-promoting activity of these waste products for valorization. Freeze-dried and pulverized cabbage wastes had a high bile acid binding capacity and the capsicum wastes inhibited glucose dialysis more effectively. Methanolic extracts prepared with conventional solvent extraction and ultrasound-assisted extraction were analyzed to determine their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, in vitro α-amylase inhibitory, in vitro lipase inhibitory, and prebiotic activity. Crude extracts of cabbage and capsicum wastes were screened using GC-MS analysis. The cabbage waste extracts showed high antioxidant activities but did not inhibit α-amylase. The capsicum waste extracts inhibited both lipase and α-amylase activities and supported the growth of the probiotic bacterium, Lactobacilli brevis. Volatile compounds of the vegetables consisted mainly of phenols and fatty acid esters. In all assays except the α-amylase inhibition assay, the extracts prepared with ultrasound-assisted solvent extraction showed higher activity than those prepared using the conventional method. The capsicum seed core and cabbage outer leaves are potential sources of phytochemicals and antioxidant fibers. Capsicum waste extract supported probiotic bacterial growth without a lag phase. These waste products may be processed into high-value functional ingredients.
    Matched MeSH terms: Gas Chromatography-Mass Spectrometry
  18. Romero Rocamora C, Ramasamy K, Meng Lim S, Majeed ABA, Agatonovic-Kustrin S
    J Pharm Biomed Anal, 2020 Jan 30;178:112909.
    PMID: 31618702 DOI: 10.1016/j.jpba.2019.112909
    A high-performance thin-layer chromatography (HPTLC) method combined with effect-directed-analysis (EDA) was developed to screen the antioxidant, neuroprotective and antidiabetic effects in essential oils derived from lavender flower, lemon myrtle, oregano, peppermint, sage, and rosemary leaves (Lamiaceae family). HPTLC hyphenated with microchemical (DPPH•, p-anisaldehyde, and ferric chloride) derivatizations, was used to evaluate antioxidant activity, presence of phytosterols and terpenoids, and polyphenolic content, while the combination with biochemical (α-amylase and acetylcholine esterase (AChE) enzymatic) derivatizations was used to asses α-amylase and AChE inhibitory activities. The superior antioxidant activity of oregano leaf extract is attributed to the presence of high levels of aromatic compounds, like polyphenolic acids. The strongest α-amylase inhibition was observed in lemon myrtle and rosemary plus extracts due to the presence of monoterpenes. Rosemary and sage extracts exhibit the highest AChE inhibition activity, with 1 μL essential oils being more potent than the recommended daily dose of donepezil. This superior neuroprotection was attributed to the presences of di- and triterpenes that displayed strong AChE inhibition and antioxidant potential in DPPH• free radical assay. Antioxidant activity was related to phenolic content (R = 0.49), while α-amylase inhibitory activity was positively related to antioxidant activity (R = 0.20) and terpenoid/sterol content (R = 0.31). AChE inhibitory activity was correlated (R = 0.80) to the combined effect of phenolics and terpenoids. Thus, the superior AChE inhibitory and neuroprotection potential of rosemary and sage essential oils could be attributed to joint effects of main phenolic and terpene constituents. The hyphenated HPTLC method provided rapid bioanalytical profiling of highly complex essential oil samples.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods*; Chromatography, Thin Layer/methods*
  19. Fan X, Matsumoto H, Wang Y, Hu Y, Liu Y, Fang H, et al.
    Environ Sci Technol, 2019 Nov 19;53(22):13042-13052.
    PMID: 31631659 DOI: 10.1021/acs.est.9b04616
    Rice fungal pathogens, responsible for severe rice yield loss and biotoxin contamination, cause increasing concerns on environmental safety and public health. In the paddy environment, we observed that the asymptomatic rice phyllosphere microenvironment was dominated by an indigenous fungus, Aspergillus cvjetkovicii, which positively correlated with alleviated incidence of Magnaporthe oryzae, one of the most aggressive plant pathogens. Through the comparative metabolic profiling for the rice phyllosphere microenvironment, two metabolites were assigned as exclusively enriched metabolic markers in the asymptomatic phyllosphere and increased remarkably in a population-dependent manner with A. cvjetkovicii. These two metabolites evidenced to be produced by A. cvjetkovicii in either a phyllosphere microenvironment or artificial media were purified and identified as 2(3H)-benzofuranone and azulene, respectively, by gas chromatography coupled to triple quadrupole mass spectrometry and nuclear magnetic resonance analyses. Combining with bioassay analysis in vivo and in vitro, we found that 2(3H)-benzofuranone and azulene exerted dissimilar actions at the stage of infection-related development of M. oryzae. A. cvjetkovicii produced 2(3H)-benzofuranone at the early stage to suppress MoPer1 gene expression, leading to inhibited mycelial growth, while azulene produced lately was involved in blocking of appressorium formation by downregulation of MgRac1. More profoundly, the microenvironmental interplay dominated by A. cvjetkovicii significantly blocked M. oryzae epidemics in the paddy environment from 54.7 to 68.5% (p < 0.05). Our study first demonstrated implication of the microenvironmental interplay dominated by indigenous and beneficial fungus to ecological balance and safety of the paddy environment.
    Matched MeSH terms: Gas Chromatography-Mass Spectrometry
  20. Kar SS, Bhat VG, Shenoy VP, Bairy I, Shenoy GG
    Chem Biol Drug Des, 2019 01;93(1):60-66.
    PMID: 30118192 DOI: 10.1111/cbdd.13379
    In our efforts to develop druggable diphenyl ethers as potential antitubercular agents, a series of novel diphenyl ether derivatives (5a-f, 6a-f) were designed and synthesized. The representative compounds showed promising in vitro activity against drug-susceptible, isoniazid-resistant, and multidrug-resistant strains of Mycobacterium tuberculosis with MIC values of 1.56 μg/ml (6b), 6.25 μg/ml (6a-d), and 3.125 μg/ml (6b-c), respectively. All the synthesized compounds exhibited satisfactory safety profile (CC50  > 300 μg/ml) against Vero and HepG2 cells. Reverse phase HPLC method was used to probe the physicochemical properties of the synthesized compounds. This series of compounds demonstrated comparatively low logP values. pKa values of representative compounds indicated that they were weak acids. Additionally, in vitro human liver microsomal stability assay confirmed that the synthesized compounds possessed acceptable stability under study conditions. The present study thus establishes compound 6b as the most promising antitubercular agent with acceptable drug-likeness.
    Matched MeSH terms: Chromatography, High Pressure Liquid
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