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Antioxidant activity-guided separation of coumarins and lignan from Melicope glabra (Rutaceae)

Kassim NK, Rahmani M, Ismail A, Sukari MA, Ee GC, Nasir NM, et al.

Food Chem, 2013 Aug 15;139(1-4):87-92.
PMID: 23561082 DOI: 10.1016/j.foodchem.2013.01.108

The ethyl acetate and methanol bark extracts of Melicope glabra were evaluated for their antioxidant capacities by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and β-carotene bleaching/linoleic acid system. Both extracts exhibited strong inhibition against the DPPH radical (IC50 values of 24.81 and 13.01 μg ml(-1), respectively) and strong antioxidant activity in β-carotene bleaching assay. Both samples were found to have high phenolic content with values of 39 and 44 mg GAE/g as indicated by Follin-Ciocalteau's reagent. Antioxidant TLC assay-guided isolation on the methanol extract led to the isolation of a new pyranocoumarin, glabranin (1), umbelliferone (2), scopoletin (3) and sesamin (4), and their structures were determined by spectroscopy. Compounds (1-3) showed significant activities on DPPH free radical with the IC50 of 240.20, 810.02 and 413.19 μg ml(-1), respectively. However, in β-carotene bleaching assay, sesamin (4) showed higher inhibitory activity (1 mg ml(-1), 95%) than glabranin (1) (1 mg ml(-1), 74%), whilst umbelliferone (2) and scopoletin (3) were slightly pro-oxidant.

Matched MeSH terms: Chromatography, Thin Layer
Identification of metabolites from benzo[a]pyrene oxidation by ligninolytic enzymes of Polyporus sp. S133

Hadibarata T, Kristanti RA

J Environ Manage, 2012 Nov 30;111:115-9.
PMID: 22835655 DOI: 10.1016/j.jenvman.2012.06.044

The biodegradation of benzo[a]pyrene (BaP) by using Polyporus sp. S133, a white-rot fungus isolated from oil-contaminated soil was investigated. Approximately 73% of the initial concentration of BaP was degraded within 30 d of incubation. The isolation and characterization of 3 metabolites by thin layer chromatography, column chromatography, and UV-vis spectrophotometry in combination with gas chromatography-mass spectrometry, indicated that Polyporus sp. S133 transformed BaP to BaP-1,6-quinone. This quinone was further degraded in 2 ways. First, BaP-1,6-quinone was decarboxylated and oxidized to form coumarin, which was then hydroxylated to hydroxycoumarin, and finally to hydroxyphenyl acetic acid by addition of an epoxide group. Second, Polyporus sp. S133 converted BaP-1,6-quinone into a major product, 1-hydroxy-2-naphthoic acid. During degradation, free extracellular laccase was detected with reduced activity of lignin peroxidase, manganese-dependent peroxidase and 2,3-dioxygenase, suggesting that laccase and 1,2-dioxygenase might play an important role in the transformation of PAHs compounds.

Matched MeSH terms: Chromatography, Thin Layer
Chemical constituents of Melicope ptelefolia

Shaari K, Zareen S, Akhtar MN, Lajis NH

Nat Prod Commun, 2011 Mar;6(3):343-8.
PMID: 21485271

Phytochemical investigations on the methanolic extract of Melicope ptelefolia Champ ex Benth. resulted in the isolation of three new compounds, identified as 3beta-stigmast-5-en-3-ol butyl tridecanedioate (melicoester) (1), (2Z, 6Z, 10Z, 14Z, 18Z, 22Z, 26E)-3', 7', 11', 15', 19', 23', 27', 31'-octamethyldotriaconta-2, 6, 10, 14, 18, 22, 26, 30-octadecanoate (melicopeprenoate) (2) and p-O-geranyl-7"-acetoxy coumaric acid (3). The compounds were isolated along with twenty-one other known compounds, lupeol (4), oleanolic acid (5), kokusaginine (6) genistein (7), p-O-geranyl coumaric acid (8), 4-stigmasten-3-one (9), 3beta-hydroxystigma-5-en-7-one (10) cis-phytyl palmitate (11), dodecane, dodecan-1-ol, ceryl alcohol, hentriacontanoic acid, eicosane, n-amyl alcohol, caprylic alcohol, octatriacontane, nonatriacontane, hexatriencontan-1-ol, methyl octacosanoate, beta-sitosterol, beta-sitosterol glucoside. Structures of all the compounds were established on the basis of MS and 1D and 2D NMR spectral data, as well as comparison with reported data.

Matched MeSH terms: Chromatography, Thin Layer
Fate and cometabolic degradation of benzo[a]pyrene by white-rot fungus Armillaria sp. F022

Hadibarata T, Kristanti RA

Bioresour Technol, 2012 Mar;107:314-8.
PMID: 22209445 DOI: 10.1016/j.biortech.2011.12.046

Armillaria sp. F022, a white-rot fungus isolated from a tropical rain forest in Samarinda, Indonesia, was used to biodegrade benzo[a]pyrene (BaP). Transformation of BaP, a 5-ring polycyclic aromatic hydrocarbon (PAH), by Armillaria sp. F022, which uses BaP as a source of carbon and energy, was investigated. However, biodegradation of BaP has been limited because of its bioavailability and toxicity. Five cosubstrates were selected as cometabolic carbon and energy sources. The results showed that Armillaria sp. F022 used BaP with and without cosubstrates. A 2.5-fold increase in degradation efficiency was achieved after addition of glucose. Meanwhile, the use of glucose as a cosubstrate could significantly stimulate laccase production compared with other cosubstrates and not using any cosubstrate. The metabolic pathway was elucidated by identifying metabolites, conducting biotransformation studies, and monitoring enzyme activities in cell-free extracts. The degradation mechanism was determined through the identification of several metabolites: benzo[a]pyrene-1,6-quinone, 1-hydroxy-2-benzoic acid, and benzoic acid.

Matched MeSH terms: Chromatography, Thin Layer
Fulltext Antihyperglycemic effect of orthosiphon stamineus benth leaves extract and its bioassay-guided fractions

Mohamed EA, Mohamed AJ, Asmawi MZ, Sadikun A, Ebrika OS, Yam MF

Molecules, 2011 May 04;16(5):3787-801.
PMID: 21544041 DOI: 10.3390/molecules16053787

Preliminary investigations were carried out to evaluate the antidiabetic effects of the leaves of O. stamineus extracted serially with solvents of increasing polarity (petroleum ether, chloroform, methanol and water); bioassay-guided purification of plant extracts using the subcutaneous glucose tolerance test (SbGTT) was also carried out. Only the chloroform extract, given at 1 g/kg body weight (b.w.), significantly reduced (P < 0.05) the blood glucose level of rats loaded subcutaneously with 150 mg/kg (b.w.) glucose. The active chloroform extract of O. stamineus was separated into five fractions using a dry flash column chromatography method. Out of the five fractions tested, only chloroform fraction 2 (Cƒ2), at the dose of 1 g/kg (b.w.) significantly inhibited (P < 0.05) blood glucose levels in SbGTT. Active Cƒ2 was split into two sub-fractions Cƒ2-A and Cƒ2-B, using a dry flash column chromatography method. The activities Cƒ2-A and Cƒ2-B were investigated using SbGTT, and the active sub-fraction was then further studied for anti-diabetic effects in a streptozotocin-induced diabetic rat model. The results clearly indicate that Cƒ2-B fraction exhibited a blood glucose lowering effect in fasted treated normal rats after glucose-loading of 150 mg/kg (b.w.). In the acute streptozotocin-induced diabetic rat model, Cƒ2-B did not exhibit a hypoglycemic effect on blood glucose levels up to 7 hours after treatment. Thus, it appears that Cƒ2-B functions similarly to metformin, which has no hypoglycemic effect but demonstrates an antihyperglycemic effect only in normogycemic models. The effect of Cƒ2-B may have no direct stimulatory effects on insulin secretion or on blood glucose levels in diabetic animal models. Verification of the active compound(s) within the active fraction (Cƒ2-B) indicated the presence of terpenoids and, flavonoids, including sinensitin.

Matched MeSH terms: Chromatography, Thin Layer
Optimization of enzymatic synthesis of palm-based kojic acid ester using response surface methodology

Ashari SE, Mohamad R, Ariff A, Basri M, Salleh AB

J Oleo Sci, 2009;58(10):503-10.
PMID: 19745577

Kojic acid monooleate is a fatty acid derivative of kojic acid which can be widely used as a skin whitening agent in a cosmetic applications. In avoiding any possible harmful effects from chemically synthesized product, the enzymatic synthesis appears to be the best way to satisfy the consumer demand nowadays. The ability of immobilized lipase from Rhizomucor meihei (lipozyme RMIM) to catalyze the direct esterification of kojic acid and oleic acid was investigated. Response Surface Methodology (RSM) and 5-level-4-factor central composite rotatable were employed to evaluate the effects of synthesis parameters such as enzyme amount (0.1-0.4 g), temperature (30-60 degrees C), substrate molar ratio (1-4 mmol, kojic acid:oleic acid) and reaction time (24-48 h) on percentage molar conversion to kojic acid monooleate. Analysis of the product using TLC, GC and FTIR showed the presence of kojic acid monooleate. The optimal conditions for the enzymatic reaction were obtained after analysis with backward elimination using 0.17 g of enzyme and 4 mmol of substrate at 52.50 degrees C for 42 h. Under these conditions the esterification percentage was 37.21%. The results demonstrated that response surface methodology can be applied effectively to optimize the lipase-catalysed synthesis of kojic acid monooleate. The optimum conditions can be used to scale up the process.

Matched MeSH terms: Chromatography, Thin Layer
Biolistic mediated production of transgenic oil palm

Kadir Ahmad Parveez G

Methods Mol Biol, 2008;477:301-20.
PMID: 19082956 DOI: 10.1007/978-1-60327-517-0_23

Physical and biological parameters affecting DNA delivery into oil palm embryogenic calli using the biolistic device are optimized. Five different promoters are also evaluated to identify the most suitable promoter for use in oil palm transformation. Finally, the effectiveness of kanamycin, geneticin (G418), neomycin, hygromycin, and herbicide Basta as selection agents to inhibit growth of oil palm embryogenic calli is evaluated. Combination of optimized parameters, best promoter and selection agent is later used to transform oil palm embryogenic calli for producing transgenic oil palm plants. Bombarded embryogenic calli are exposed to 50 mg/l of Basta after 3 weeks. Basta-resistant embryogenic calli started to emerge five to six months in medium containing Basta. The Basta-resistant embryogenic calli are proliferated until they reach a specific size, and the Basta-resistant calli are later individually isolated and regenerated to produce complete plantlets. The complete regenerated plantlets are evaluated for the presence of transgenes by PCR, Southern and thin layer chromatography analyses.

Matched MeSH terms: Chromatography, Thin Layer
Studies on diuretic and hypouricemic effects of Orthosiphon stamineus methanol extracts in rats

Arafat OM, Tham SY, Sadikun A, Zhari I, Haughton PJ, Asmawi MZ

J Ethnopharmacol, 2008 Aug 13;118(3):354-60.
PMID: 18602231 DOI: 10.1016/j.jep.2008.04.015

AIM OF THE STUDY: Orthosiphon stamineus (Labiatae) is a traditional folk medicine widely used in Southeast Asia for the treatment of several kidney disorders, gout and as a diuretic. This study was conducted to examine the diuretic and hypouricemic effects of Orthosiphon stamineus leaf extracts.
MATERIALS AND METHODS: The diuretic effect of different methanol extracts was examined by treating different groups of Sprague-Dawley rats with single (2g/kg) oral doses of methanol and methanol:water (1:1) extracts. Hydrochlorothiazide (10mg/kg) was used as positive control in acute study. Methanol and methanol water (1:1) extracts at 0.5 g/kg were administered for a period of 7 consecutive days. Cumulative urine volume and electrolytes (Na+ and K+) concentrations at different time intervals were measured. On the other hand, hypouricemic activity of methanol:water extract (1:1) was experimented using different oral single doses (0.25, 0.5, 1 and 2g/kg). Allopurinol was used as positive control. Uric acid concentration in serum was analyzed by using RP-HPLC at 280 nm.
RESULTS: Sodium and potassium excretion increased significantly (p<0.05 and <0.01) in the first 8h of treatment with a single dose (2g/kg) of the extracts in a pattern comparable to that of the known diuretic hydrochlorothiazide. Meanwhile, repeated administration of 0.5 g/kg methanol:water (1:1) extract showed a significant increase in urine volume (from day 3 to day 7) (p<0.01) and electrolytes excretion (Na+ and K+) from day 2 to day 7 (p<0.05 and <0.01). On the other hand, 0.5, 1 and 2g/kg of methanol:water (1:1) extract and the standard allopurinol reduced the serum urate level in hyperuricemic rats at hour 6.
CONCLUSION: These results provided an evidence of the high tendency of methanol:water (1:1) extract of Orthosiphon stamineus towards diuretic and hypouricemic effects in rats.

Matched MeSH terms: Chromatography, Thin Layer
Xanthones from Garcinia parvifolia

Xu YJ, Lai YH, Imiyabir Z, Goh SH

J Nat Prod, 2001 Sep;64(9):1191-5.
PMID: 11575954

Nine new xanthones, parvixanthones A-I (1-9), isolated from the dried bark of Garcinia parvifolia, were found to have a common 1,3,6,7-oxygenated pattern for their xanthone nucleus, but various oxygenated isoprenyl or geranyl substituent groups. The structures were determined by spectroscopic methods.

Matched MeSH terms: Chromatography, Thin Layer
Four new clerodane diterpenoids from Callicarpa pentandra

Xu J, Harrison LJ, Vittal JJ, Xu YJ, Goh SH

J Nat Prod, 2000 Aug;63(8):1062-5.
PMID: 10978198

Leaf extracts of Callicarpa pentandra provided four new clerodane-type diterpenoids (1-4), of which 1, 2, and 4 have ring-A-contracted structures. Their structures and stereochemistry were established by spectral data interpretation, and for 3 also by single-crystal X-ray diffraction.

Matched MeSH terms: Chromatography, Thin Layer
Fulltext Induction of cytotoxicity by Bruguiera gymnorrhiza in human breast carcinoma (MCF-7) cell line via activation of the intrinsic pathway

Chaudhry GE, Rahman NH, Sevakumaran V, Ahmad A, Mohamad H, Zafar MN, et al.

J Adv Pharm Technol Res, 2020 10 10;11(4):233-237.
PMID: 33425710 DOI: 10.4103/japtr.JAPTR_81_20

Breast cancer is among the frequently occurring cancer worldwide. The foremost underline aim of this study was to determine the growth inhibitory effect along with mechanistic study of a Bruguiera gymnorrhiza extract on MCF-7. The cytotoxicity activity was determined by using the MTS assay. Butanol extract exhibited the maximum cytotoxicity activity against the MCF-7 cells with IC50 of 3.39 μg/mL, followed by diethyl ether and methanol extract (IC50 at 16.22 μg/mL and 37.15 μg/mL, respectively) at 72 h. The DeadEndTM Colorimetric Apoptosis Detection System confirmed the induction of apoptosis (via DNA fragmentation) in MCF-7 cells. Both butanol and diethyl ether extracts of B. gymnorrhiza significantly increase the caspase-3 level. However, the diethyl ether extract induced higher caspase-9 levels compared to caspase-8, suggesting that the intrinsic pathway was the major route in the process of apoptosis. Thin-layer chromatography profiling demonstrated the presence of phenolic, terpene, and alkaloid compounds in crude methanol, diethyl ether, and butanol extracts. The phytochemicals present in the extracts of B. gymnorrhiza might have the potential to be a future therapeutic agent against breast cancer.

Matched MeSH terms: Chromatography, Thin Layer
Biological evaluation of curcumin and related diarylheptanoids

Abas F, Hui LS, Ahmad S, Stanslas J, Israf DA, Shaari K, et al.

Z Naturforsch C J Biosci, 2006 12 2;61(9-10):625-31.
PMID: 17137104

Nine derivatives of three natural diarylheptanoids, curcumin, demethoxycurcumin and bisdemethoxycurcumin, were prepared. Their antioxidant, free radical scavenging, nitric oxide (NO) inhibitory and cytotoxic activities were evaluated and compared with those of the respective natural compounds. Curcumin (1), demethoxycurcumin (2), demethyldemethoxy-curcumin (C3), diacetyldemethoxycurcumin (AC2) and triacetyldemethylcurcumin (AC5) exhibited higher antioxidant activity than quercetin while products from demethylation of 1 and 2 exhibited higher free radical scavenging activity. Compounds AC2 and AC5 were found to be most active in inhibiting breast cancer cells (MCF-7) proliferation with IC50 values of 6.7 and 3.6 microM, respectively. The activity of AC2 is almost doubled and of AC5 almost tripled as compared to curcumin. Their selectivity towards different cell lines is also more noticeable. Compounds AC2 and AC5 also showed increased activity against a human prostate cancer cell line (DU-145) and non-small lung cancer cell line (NCI-H460) with IC50 values of 20.4, 16.3 and 18.3, 10.7 microM, respectively.

Matched MeSH terms: Chromatography, Thin Layer
In Vitro Cytotoxicity and Anti-inflammatory Cytokinine Activity Study of Three Isolated Novel Compounds of Prismatomeris glabra

Alkadi KAA, Ashraf K, Adam A, Shah SAA, Taha M, Hasan MH, et al.

J Pharm Bioallied Sci, 2020 12 21;13(1):116-122.
PMID: 34084057 DOI: 10.4103/jpbs.JPBS_279_19

Objectives: The aim of the present study was to isolate and evaluate cytotoxicity and anti-inflammatory activities of new novel compounds isolated from Prismatomeris glabra.
Materials and Methods: Dried root of P. glabra was extracted under reflux with methyl alcohol, fractionated through the vacuum liquid chromatography technique, and evaporated and then purified the compounds using column chromatography and preparative thin-layer chromatography. THP-1 cells were treated with amentoflavone, 5,7,4'-hydroxyflavonoid, and stigmasterol with various concentrations (0-30 µg/mL) and then incubated with MTS reagent for 2h. Treatment was done for 24, 48, and 72h. Then, effects of these compounds were also tested on PGE2, TNF-α, and IL-6 expression in human THP-1-derived macrophage cells for 24h.
Results: Three new compounds such as amentoflavone, 5,7,4'-hydroxyflavonoid, and stigmasterol were isolated. After 24h of incubation, a significant decrease in cell viability was reported with IC50 values of amentoflavone, 5,7,4'- hydroxyflavonoid, and stigmasterol (21 µg/mL ≡ 38 M), (18 µg/mL ≡ 66 M) and (20 µg/mL ≡ 48.5 M), respectively. Whereas for 48 and 72h treatment showed a less decreased cell viability compared with 24h treatment. These compounds also showed a significant reduction in the production of TNF-α, IL-6, and PGE2 in a dose-dependent manner.
Conclusions: The isolated new compounds showed significant cytotoxicity and anti-inflammatory effects.

Matched MeSH terms: Chromatography, Thin Layer
Fulltext Antimicrobial activity of artemisinin and precursor derived from in vitro plantlets of Artemisia annua L

Appalasamy S, Lo KY, Ch'ng SJ, Nornadia K, Othman AS, Chan LK

Biomed Res Int, 2014;2014:215872.
PMID: 24575401 DOI: 10.1155/2014/215872

Artemisia annua L., a medicinal herb, produces secondary metabolites with antimicrobial property. In Malaysia due to the tropical hot climate, A. annua could not be planted for production of artemisinin, the main bioactive compound. In this study, the leaves of three in vitro A. annua L. clones were, extracted and two bioactive compounds, artemisinin and a precursor, were isolated by thin layer chromatography. These compounds were found to be effective in inhibiting the growth of Gram-positive and Gram-negative bacteria but not Candida albicans. Their antimicrobial activity was similar to that of antibactericidal antibiotic streptomycin. They were found to inhibit the growth of the tested microbes at the minimum inhibition concentration of 0.09 mg/mL, and toxicity test using brine shrimp showed that even the low concentration of 0.09 mg/mL was very lethal towards the brine shrimps with 100% mortality rate. This study hence indicated that in vitro cultured plantlets of A. annua can be used as the alternative method for production of artemisinin and its precursor with antimicrobial activities.

Matched MeSH terms: Chromatography, Thin Layer
Fulltext Enzymatic synthesis of polyphenol glycosides catalyzed by transglycosylation reaction of cyclodextrin glucanotransferase derived from Trichoderma viride

Nazir S, Sulistyo J, Hashmi MI, Ho AL, Khan MS

J Food Sci Technol, 2018 Aug;55(8):3026-3034.
PMID: 30065412 DOI: 10.1007/s13197-018-3223-x

Present study was conducted to evaluate the ability of Trichoderma viride as a source of cyclodextrin glucanotransferase that has shown transglycosylation activity in the presence of polyphenolic constituents extracted from Moringa oleifera leaves as its acceptor and wheat flour as its substrate to catalyze synthesis of polyphenolic glycosides as transglycosylation (transfer) reaction products. The enzymatic synthesized polyphenolic glycosides were then purified using octa-dodecyl-functionalized silica gel column chromatography prior to analysis using thin layer chromatography and high performance liquid chromatography and identified using nuclear magnetic resonance (NMR) spectroscopy. The high performance liquid chromatogram performed that the isolated transglycosylation products had retention times and concentration at 1.446 min (0.0017 mg/ml), 1.431 min (0.14 mg/ml), and 1.474 min (0.012 mg/ml), respectively, compared to the retention time of arbutin (1.474 min) that was applied as authentic standard for polyphenol glycoside. Moreover, observation using 1H NMR as well as 13C NMR showed that structures of the transglycosylation products were identified as gallic acid-4-O-β-glucopyranoside, ellagicacid-4-O-β-glucopyranoside, and catechin-4'-O-glucopyranoside, respectively.

Matched MeSH terms: Chromatography, Thin Layer
Fulltext In Vitro antioxidant and xanthine oxidase inhibitory activities of methanolic Swietenia mahagoni seed extracts

Sahgal G, Ramanathan S, Sasidharan S, Mordi MN, Ismail S, Mansor SM

Molecules, 2009 Nov 06;14(11):4476-85.
PMID: 19924080 DOI: 10.3390/molecules14114476

This study examines the in vitro antioxidant activities of the methanol extract of Swietenia mahagoni seeds (SMCM seed extract). The extract was screened for possible antioxidant activities by free radical scavenging activity (DPPH), xanthine oxidase inhibition (XOI), hydrogen peroxide scavenging activity (HPSA) and ferric-reducing antioxidant power (FRAP) assays. The total phenolic and flavonoid contents were also determined. The extract exhibits antioxidant activity of 23.29% with an IC(50 )value of 2.3 mg/mL in the DPPH radical scavenging method, 47.2% in the XOI assay, 49.5% by the HPSA method, and 0.728 mmol/Fe(II)g in the FRAP method at the concentration tested. The amount of total phenolics and flavonoid contents was 70.83 mg gallic acid equivalent (GAE) and 2.5 +/- 0.15 mg of catechin equivalent per gram of dry extract, respectively. High Performance Thin Layer Chromatography (HPTLC) screening indicates the presence of phenolic compounds in the SMCM seed extract. The results indicate that the extract has both high free radical scavenging and xanthine oxidase inhibition activity. The antioxidant activity of SMCM seed extract is comparable with that of other Malaysian tropical fruits and herbal plants.

Matched MeSH terms: Chromatography, Thin Layer
A screening method for cardiovascular active compounds in marine algae

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
Effect of Gibberellin and Heat Shock on the Lipid Composition of Endoplasmic Reticulum in Barley Aleurone Layers

Grindstaff KK, Fielding LA, Brodl MR

Plant Physiol, 1996 Feb;110(2):571-581.
PMID: 12226205

The heat-shock responses of barley (Hordeum vulgare L. cv Hi- malaya) aleurone layers incubated with or without gibberellic acid (GA3) were compared. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that heat shock blocked the synthesis and secretion of secretory proteins from GA3-treated layers but not untreated layers. This suppression of secretory protein synthesis has been correlated with changes in endoplasmic reticulum (ER) membranes (F.C. Belanger, M. R. Brodl, T.-h.D. Ho [1986] Proc Natl Acad Sci USA 83: 1354-1358; L. Sticher, A.K. Biswas, D.S. Bush, R.L. Jones [1990] Plant Physiol 92: 506-513). Our secretion data suggested that the ER membranes of aleurone layers incubated without GA3 may be more heat shock tolerant. To investigate this, the lipid profiles of membrane extracts in aleurone layers labeled with [14C]glycerol were examined. Heat shock markedly increased [14C]glycerol incorporation into phosphatidylcholine (PC), and gas chromatography revealed an increase in the amount of saturated fatty acids associated with thin layer chromatography-purified PC in GA3-treated layers. In contrast, aleurone layers incubated without GA3 at normal temperature contained PC-associated fatty acids with a greater degree of saturation than GA3-treated layers. Heat shock modestly increased the degree of fatty acid saturation in untreated aleurone layers. This same trend was noted in fatty acids isolated from ER membranes purified by continuous sucrose density centrifugation. We propose that increased fatty acid saturation may help sustain ER membrane function in heat-shocked aleurone layers incubated in the absence of GA3.

Matched MeSH terms: Chromatography, Thin Layer
Fulltext The Role of Semipurified Fractions Isolated from Quercus infectoria on Bone Metabolism by Using hFOB 1.19 Human Fetal Osteoblast Cell Model

Abdullah AR, Hapidin H, Abdullah H

Evid Based Complement Alternat Med, 2018;2018:5319528.
PMID: 29861772 DOI: 10.1155/2018/5319528

Background. Quercus infectoria (QI) is a plant used in traditional medicines in Asia. The plant was reported to contain various active phytochemical compounds that have potential to stimulate bone formation. However, the precise mechanism of the stimulation effect of QI on osteoblast has not been elucidated. The present study was carried out to isolate QI semipurified fractions from aqueous QI extract and to delineate the molecular mechanism of QI semipurified fraction that enhanced bone formation by using hFOB1.19 human fetal osteoblast cell model. Methods. Isolation of QI semipurified fractions was established by means of column chromatography and thin layer chromatography. Established QI semipurified fractions were identified using Liquid Chromatography-Mass Spectrometry (LC-MS). Cells were treated with derived QI semipurified fractions and investigated for mineralization deposition and protein expression level of BMP-2, Runx2, and OPN by ELISA followed gene expression analysis of BMP-2 and Runx2 by RT-PCR. Results. Column chromatography isolation and purification yield Fractions A, B, and C. LC-MS analysis reveals the presence of polyphenols in each fraction. Results show that QI semipurified fractions increased the activity and upregulated the gene expression of BMP-2 and Runx2 at day 1, day 3, and day 7. OPN activity increased in cells treated with QI semipurified fractions at day 1 and day 3. Meanwhile, at day 7, expression of OPN decreased in activity. Furthermore, the study showed that combination of Fractions A, B, and C with osteoporotic drug (pamidronate) further increased the activity and upregulated the gene expression of BMP-2 and Runx2. Conclusions. These findings demonstrated that polyphenols from semipurified fractions of QI enhanced bone formation through expression of the investigated bone-related marker that is its potential role when combined with readily available osteoporotic drug.

Matched MeSH terms: Chromatography, Thin Layer
Polyunsaturated fatty acid levels in red cell membranes of unmedicated schizophrenic patients

Peet M, Shah S, Selvam K, Ramchand CN

World J Biol Psychiatry, 2004 Apr;5(2):92-9.
PMID: 15179668

There are several reports of reduced levels of polyunsaturated fatty acids (PUFA), particularly arachidonic acid (AA) and docosahexaenoic acid (DHA), in membrane phospholipid from various tissues including red blood cells (RBC) taken from schizophrenic patients. However, reports have not been entirely consistent and most studies have been confounded by the potential effects of environmental factors including antipsychotic medication and diet. We measured PUFA levels in RBC from two separate groups of unmedicated patients and control subjects from India and Malaysia, populations which have substantial differences in diet. We found no significant difference in levels of AA between patients and control subjects in either population. Levels of adrenic acid were significantly reduced, and levels of DHA significantly increased in both clinical populations. However, diet-related differences in DHA between the populations from India and Malaysia were much greater than differences between schizophrenic patients and controls. It is concluded that reduced RBC membrane levels of AA and DHA are not pathognomic of schizophrenia but that variations in cell membrane fatty acid levels are an epiphenomenon which may reflect underlying abnormalities of phospholipid and fatty acid metabolism and their interaction with environmental factors including medication and diet.

Matched MeSH terms: Chromatography, Thin Layer

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