MyMedR

Fluorescence studies of selected 2-alkylaminopyrimidines

Abdullah Z, Tahir NM, Abas MR, Aiyub Z, Low BK

Molecules, 2004 Jun 30;9(7):520-6.

The reactions of 2-chloropyrimidine with methylamine, ethylamine and piperidine gave the corresponding 2-N-methylamino-, 2-N-ethylamino- and 2N- piperidinopyrimidines, respectively. The fluorescence properties of these alkylamino derivatives in chloroform, ethyl acetate, carbon tetrachloride, acetone, ether, ethanol and methanol were studied. All the alkylamino derivatives showed the highest fluorescence intensity in polar protic solvents; thus 2-N-methylaminopyrimidine (highest fluorescence intensity at 377 nm when excited at 282 nm) and 2-N-ethylaminopyrimidine (highest fluorescence intensity at 375 nm, when excited at 286 nm) showed the highest fluorescence in methanol. In ethanol, 2-N-piperidinopyrimidine showed a fluorescence peak at 403 nm when excited at 360 nm and in chloroform it fluoresced at 392 nm when excited at 356 nm.

Polyphenols in cocoa and cocoa products: is there a link between antioxidant properties and health?

Jalil AM, Ismail A

Molecules, 2008 Sep 16;13(9):2190-219.

PMID: 18830150

Cocoa and cocoa products have received much attention due to their significant polyphenol contents. Cocoa and cocoa products, namely cocoa liquor, cocoa powder and chocolates (milk and dark chocolates) may present varied polyphenol contents and possess different levels of antioxidant potentials. For the past ten years, at least 28 human studies have been conducted utilizing one of these cocoa products. However, questions arise on which of these products would deliver the best polyphenol contents and antioxidant effects. Moreover, the presence of methylxanthines, peptides, and minerals could synergistically enhance or reduce antioxidant properties of cocoa and cocoa products. To a greater extent, cocoa beans from different countries of origins and the methods of preparation (primary and secondary) could also partially influence the antioxidant polyphenols of cocoa products. Hence, comprehensive studies on the aforementioned factors could provide the understanding of health-promoting activities of cocoa or cocoa products components.

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.

Fulltext Evaluation of antioxidant and antibacterial activities of aqueous, methanolic and alkaloid extracts from Mitragyna speciosa (Rubiaceae family) leaves

Parthasarathy S, Bin Azizi J, Ramanathan S, Ismail S, Sasidharan S, Said MI, et al.

Molecules, 2009;14(10):3964-74.

PMID: 19924042 DOI: 10.3390/molecules14103964

Studies on the antioxidant and antimicrobial activities of Mitragyna speciosa leaf extracts are lacking. In this study the antioxidant properties of water, methanolic and alkaloid M. speciosa leaf extracts were evaluated using the DPPH (2,2-diphenyl-1- picrylhydrazyl) radical scavenging method. The amount of total phenolics and flavanoid contents were also estimated. The DPPH IC(50) values of the aqueous, alkaloid and methanolic extracts were 213.4, 104.81 and 37.08 microg/mL, respectively. The total phenolic content of the aqueous, alkaloid and methanolic extracts were 66.0 mg, 88.4, 105.6 mg GAE/g, respectively, while the total flavanoid were 28.2, 20.0 and 91.1 mg CAE/g respectively. The antioxidant activities were correlated with the total phenolic content. This result suggests that the relatively high antioxidant activity of the methanolic extract compared to aqueous and alkaloid extract could be possibly be due to its high phenolic content. The aqueous, alkaloid and methanolic extracts were screened for antimicrobial activity. The extracts showed antimicrobial activity against Salmonella typhi and Bacillus subtilis. The minimum inhibitory concentrations (MICs) of extracts determined by the broth dilution method ranged from 3.12 to 6.25 mg/mL. The alkaloid extract was found to be most effective against all of the tested organisms.

Fulltext A new norsesquiterpenoid from a Bornean soft coral genus Nephthea

Ishii T, Matsuura H, Zhaoqi Z, Vairappan CS

Molecules, 2009;14(11):4591-6.

PMID: 19924087 DOI: 10.3390/molecules14114591

A new germacrane-type norsesquiterpenoid, 1-acetoxy-germacra-5E,10(14)-diene-4-one (1), as well as three known compounds, were isolated from the organic extracts of a Bornean soft coral Nephthea sp. Their structures were elucidated on the basis of spectroscopic data analysis.

Fulltext A new 4alpha-methylated sterol from a Nephthea sp. (Nephtheidae) Bornean soft coral

Ishii T, Matsuura H, Zhaoqi Z, Vairappan CS

Molecules, 2009;14(9):3360-6.

PMID: 19783930 DOI: 10.3390/molecules14093360

A new 4alpha-methyl sterol, 4alpha-methyl-ergosta-6,8(14),22E-triene-3beta-ol (1), was isolated along with cholesterol from a Nephthea sp. Bornean soft coral The structure of compound 1 was elucidated on the basis of spectroscopic analysis and comparison of the data with those of the related compounds.

Fulltext Grandine A, a new proaporphine alkaloid from the bark of Phoebe grandis

Mukhtar MR, Aziz AN, Thomas NF, Hadi AH, Litaudon M, Awang K

Molecules, 2009;14(3):1227-33.

PMID: 19325519 DOI: 10.3390/molecules14031227

The stem bark of Phoebe grandis afforded one new oxoproaporphine; (-)-grandine A (1), along with six known isoquinoline alkaloids: (-)-8,9-dihydrolinearisine (2), boldine, norboldine, lauformine, scortechiniine A and scortechiniine B. In addition to that of the new compound, complete 1H- and 13C-NMR data of the tetrahydroproaporphine (-)-8,9-dihydrolinearisine (2) is also reported. The alkaloids' structures were elucidated primarily by means of high field 1D- and 2D-NMR and HRMS spectral data.

Fulltext Antioxidant activity and phenolic content of Paederia foetida and Syzygium aqueum

Osman H, Rahim AA, Isa NM, Bakhir NM

Molecules, 2009;14(3):970-8.

PMID: 19305354 DOI: 10.3390/molecules14030970

The antioxidant activity of fresh and dried plant extracts of Paederia foetida and Syzygium aqueum were studied using beta-carotene bleaching and the 2,2'-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radical cation assay. The percentage of antioxidant activity for all extract samples using both assays was between 58 and 80%. The fresh samples of both plants had higher antioxidant activity than the dried samples. The results of the beta-carotene bleaching assay were correlated (R(2) = 0.9849) with those of the ABTS assay.

Fulltext Cytotoxic components of Pereskia bleo (Kunth) DC. (Cactaceae) leaves

Malek SN, Shin SK, Wahab NA, Yaacob H

Molecules, 2009;14(5):1713-24.

PMID: 19471192 DOI: 10.3390/molecules14051713

Dihydroactinidiolide (1) and a mixture of sterols [campesterol (2), stigmasterol (3) and beta-sitosterol (4)], together with the previously isolated individual compounds beta-sitosterol (4), 2,4-di-tert-butylphenol (5), alpha-tocopherol (6), phytol (7) were isolated from the active ethyl acetate fraction of Pereskia bleo (Kunth) DC. (Cactaceae) leaves. Cytotoxic activities of the above mentioned compounds against five human carcinoma cell lines, namely the human nasopharyngeal epidermoid carcinoma cell line (KB), human cervical carcinoma cell line (CasKi), human colon carcinoma cell line (HCT 116), human hormone-dependent breast carcinoma cell line (MCF7) and human lung carcinoma cell line (A549); and non-cancer human fibroblast cell line (MRC-5) were investigated. Compound 5 possessed very remarkable cytotoxic activity against KB cells, with an IC(50 )value of 0.81microg/mL. This is the first report on the cytotoxic activities of the compounds isolated from Pereskia bleo.

Fulltext Phenolic and theobromine contents of commercial dark, milk and white chocolates on the Malaysian market

Meng CC, Jalil AM, Ismail A

Molecules, 2009;14(1):200-9.

PMID: 19127248 DOI: 10.3390/molecules14010200

Chocolate contains a wide range of antioxidants that includes soluble phenolic compounds (phenolic acids, catechin, epicatechin, and proanthocyanidins), insoluble polymeric phenolics and methylxanthines. The objective of this study was to determine phenolic and theobromine contents in dark (DC), milk (MC), and white (WC) chocolates commonly found in the Malaysian marketplace. Total phenolic and flavonoids were determined by means of a spectrometric assay, while catechin, epicatechin and theobromine were quantified using a reverse-phase HPLC method. Dark chocolates exhibited the highest phenolics and flavonoids contents, followed by milk and white chocolates. Catechin and epicatechin were major flavonoids detected in dark chocolates. Theobromine was detected in dark and milk chocolates, but not in white chocolates. A high correlation (r= 0.93) between total phenolic and flavonoid contents, indicating that the major phenolic compounds in dark chocolates belong to the flavonoid class. When nutrition and health promotion are of concern, dark chocolates would be recommended over milk and white chocolates owing to their higher contents of antioxidant phenolic compounds.

Fulltext Synthesis of 2,3-dioxo-5-(substituted)-arylpyrroles and their 2-oxo-5-aryl-3-hydrazone pyrrolidine derivatives

Mohammat MF, Shaameri Z, Hamzah AS

Molecules, 2009;14(1):250-6.

PMID: 19136912 DOI: 10.3390/molecules14010250

Some novel 2,3-dioxo-5-(substituted)-arylpyrroles have been synthesized. Among these, pyrrolidine compound 1b was converted to 2,3-dioxo-5-aryl pyrrolidine 2b. Finally a set of hydrazone derivatives was obtained from the reaction of 2b with various hydrazine salts. The structures of all the new synthesized compounds were confirmed by elemental analyses, IR and 1H-NMR spectra.

Fulltext In vitro and in vivo effects of three different Mitragyna speciosa korth leaf extracts on phase II drug metabolizing enzymes--glutathione transferases (GSTs)

Azizi J, Ismail S, Mordi MN, Ramanathan S, Said MI, Mansor SM

Molecules, 2010 Jan 20;15(1):432-41.

PMID: 20110902 DOI: 10.3390/molecules15010432

In the present study, we investigate the effects of three different Mitragyna speciosa extracts, namely methanolic, aqueous and total alkaloid extracts, on glutathione transferase-specific activity in male Sprague Dawley rat liver cytosol in vitro and in vivo. In the in vitro study, the effect of Mitragyna speciosa extracts (0.01 to 750 microg/mL) against the specific activity of glutathione transferases was examined in rat liver cytosolic fraction from untreated rats. Our data show concentration dependent inhibition of cytosolic GSTs when Mitragyna speciosa extract was added into the reaction mixture. At the highest concentration used, the methanolic extract showed the highest GSTs specific activity inhibition (61%), followed by aqueous (50%) and total alkaloid extract (43%), respectively. In in vivo study, three different dosages; 50, 100 and 200 mg/kg for methanolic and aqueous extracts and 5, 10 and 20 mg/kg for total alkaloid extract were given orally for 14 days. An increase in GST specific activity was generally observed. However, only Mitragyna speciosa aqueous extract with a dosage of 100 mg/kg showed significant results: 129% compared to control.

Fulltext Revealing the power of the natural red pigment lycopene

Kong KW, Khoo HE, Prasad KN, Ismail A, Tan CP, Rajab NF

Molecules, 2010 Feb 23;15(2):959-87.

PMID: 20335956 DOI: 10.3390/molecules15020959

By-products derived from food processing are attractive source for their valuable bioactive components and color pigments. These by-products are useful for development as functional foods, nutraceuticals, food ingredients, additives, and also as cosmetic products. Lycopene is a bioactive red colored pigment naturally occurring in plants. Industrial by-products obtained from the plants are the good sources of lycopene. Interest in lycopene is increasing due to increasing evidence proving its preventive properties toward numerous diseases. In vitro, in vivo and ex vivo studies have demonstrated that lycopene-rich foods are inversely associated to diseases such as cancers, cardiovascular diseases, diabetes, and others. This paper also reviews the properties, absorption, transportation, and distribution of lycopene and its by-products in human body. The mechanism of action and interaction of lycopene with other bioactive compounds are also discussed, because these are the crucial features for beneficial role of lycopene. However, information on the effect of food processing on lycopene stability and availability was discussed for better understanding of its characteristics.

Fulltext Evaluation of the antinociceptive activity and acute oral toxicity of standardized ethanolic extract of the rhizome of Curcuma xanthorrhiza Roxb

Devaraj S, Esfahani AS, Ismail S, Ramanathan S, Yam MF

Molecules, 2010 Apr;15(4):2925-34.

PMID: 20428088 DOI: 10.3390/molecules15042925

Ethanolic extract of Curcuma xanthorrhiza was used to evaluate the analgesic and toxicity effects in vivo. The extract was standardized using GC-MS, which showed that 1 mg of Curcuma xanthorrhiza ethanolic extract contains 0.1238 mg of xanthorrhizol. The analgesic activity was studied in rats using three different models, namely the hot plate test, tail flick test and formalin-induced pain test. The acute oral toxicity was examined by the oral administration of standardized Curcuma xanthorrhiza ethanolic extract in mice at doses ranging from 300-5,000 mg/kg and observation for 14 days. Standardized Curcuma xanthorrhiza ethanolic extract did not show significant analgesic effect in the hot plate and tail flick tests. However, in the formalin-induced pain test, Curcuma xanthorrhiza ethanolic extract significantly (P < 0.05) suppressed the paw licking time of rats in both early and late phases at doses 200 and 400 mg/kg of the extract, respectively. In the acute oral toxicity study, Curcuma xanthorrhiza ethanolic extract did not show any toxic effects in mice at 5 g/kg. These experimental results suggest that the standardized Curcuma xanthorrhiza ethanolic extract showed peripheral and central antinociceptive activity associated with neurogenic pain as well as a relative absence of toxic effects which could compromise the medicinal use of this plant in folk medicine.

Fulltext Boronate derivatives of functionally diverse catechols: stability studies

Ketuly KA, Hadi AH

Molecules, 2010 Apr;15(4):2347-56.

PMID: 20428047 DOI: 10.3390/molecules15042347

Benzeneboronate of catecholic carboxyl methyl esters, N-acetyldopamine, coumarin and catechol estrogens were prepared as crystalline derivatives in high yield. Related catechol compounds with extra polar functional group(s) (OH, NH2) do not form or only partially form unstable cyclic boronate derivatives.

Fulltext Assessment of antioxidant capacity and cytotoxicity of selected Malaysian plants

Ling LT, Radhakrishnan AK, Subramaniam T, Cheng HM, Palanisamy UD

Molecules, 2010 Apr;15(4):2139-51.

PMID: 20428033 DOI: 10.3390/molecules15042139

Thirteen Malaysian plants; Artocarpus champeden, Azadirachta indica, Fragaria x ananassa, Garcinia mangostana, Lawsonia inermis, Mangifera indica, Nephelium lappaceum, Nephelium mutobile, Peltophorum pterocarpum, Psidium guajava and Syzygium aqueum, selected for their use in traditional medicine, were subjected to a variety of assays. Antioxidant capability, total phenolic content, elemental composition, as well as it cytotoxity to several cell lines of the aqueous and ethanolic extracts from different parts of these selected Malaysian plants were determined. In general, the ethanolic extracts were better free radical scavengers than the aqueous extracts and some of the tested extracts were even more potent than a commercial grape seed preparation. Similar results were seen in the lipid peroxidation inhibition studies. Our findings also showed a strong correlation of antioxidant activity with the total phenolic content. These extracts when tested for its heavy metals content, were found to be below permissible value for nutraceutical application. In addition, most of the extracts were found not cytotoxic to 3T3 and 4T1 cells at concentrations as high as 100 microg/mL. We conclude that although traditionally these plants are used in the aqueous form, its commercial preparation could be achieved using ethanol since a high total phenolic content and antioxidant activity is associated with this method of preparation.

Fulltext Pellitorine, a potential anti-cancer lead compound against HL6 and MCT-7 cell lines and microbial transformation of piperine from Piper Nigrum

Ee GC, Lim CM, Rahmani M, Shaari K, Bong CF

Molecules, 2010 Apr;15(4):2398-404.

PMID: 20428051 DOI: 10.3390/molecules15042398

Pellitorine (1), which was isolated from the roots of Piper nigrum, showed strong cytotoxic activities against HL60 and MCT-7 cell lines. Microbial transformation of piperine (2) gave a new compound 5-[3,4-(methylenedioxy)phenyl]-pent-2-ene piperidine (3). Two other alkaloids were also found from Piper nigrum. They are (E)-1-[3',4'-(methylenedioxy)cinnamoyl]piperidine (4) and 2,4-tetradecadienoic acid isobutyl amide (5). These compounds were isolated using chromatographic methods and their structures were elucidated using MS, IR and NMR techniques.

Fulltext Synthesis and physico-chemical properties of new tetraethylammonium-based amino acid chiral ionic liquids

Abdul Rahman MB, Jumbri K, Basri M, Abdulmalek E, Sirat K, Salleh AB

Molecules, 2010 Apr 05;15(4):2388-97.

PMID: 20428050 DOI: 10.3390/molecules15042388

This paper reports the synthesis of a series of new tetraethylammonium-based amino acid chiral ionic liquids (CILs). Their physico-chemical properties, including melting point, thermal stability, viscosity and ionic conductivity, have been comprehensively studied. The obtained results indicated that the decomposition for these salts proceeds in one step and the temperature of decomposition (T(onset)) is in the range of 168-210 degrees C. Several new CILs prepared in this work showed high ionic conductivity compared to the amino acid ionic liquids (AAILs) found in the literature.

Fulltext Wound healing potential of Elaeis guineensis Jacq leaves in an infected albino rat model

Sasidharan S, Nilawatyi R, Xavier R, Latha LY, Amala R

Molecules, 2010 Apr 30;15(5):3186-99.

PMID: 20657471 DOI: 10.3390/molecules15053186

ETHNOPHARMACOLOGICAL RELEVANCE: Elaeis guineensis Jacq (Arecaceae) is one of the plants that are central to the lives of traditional societies in West Africa. It has been reported as a traditional folkloric medicine for a variety of ailments. The plant leaves are also used in some parts of Africa for wound healing, but there are no scientific reports on any wound healing activity of the plant.

AIM OF THE STUDY: To investigate the effects of E. guineensis leaf on wound healing activity in rats.

METHODS: A phytochemical screening was done to determine the major phytochemicals in the extract. The antimicrobial activity of the extract was examined using the disk diffusion technique and broth dilution method. The wound healing activity of leaves of E. guineensiswas studied by incorporating the methanolic extract in yellow soft paraffin in concentration of 10% (w/w). Wound healing activity was studied by determining the percentage of wound closure, microbial examination of granulated skin tissue and histological analysis in the control and extract treated groups.

RESULTS: Phytochemical screening reveals the presence of tannins, alkaloids, steroids, saponins, terpenoids, and flavonoids in the extract. The extract showed significant activity against Candida albicans with an MIC value of 6.25 mg/mL. The results show that the E. guineensis extract has potent wound healing capacity, as evident from better wound closure, improved tissue regeneration at the wound site, and supporting histopathological parameters pertaining to wound healing. Assessment of granulation tissue every fourth day showed a significant reduction in microbial count.

CONCLUSIONS: E. guineensis accelerated wound healing in rats, thus supporting this traditional use.

Fulltext Synthesis and liquid crystalline properties of new diols containing azomethine groups

Mohammed IA, Sankar G, Khairuddean M, Mohamad AB

Molecules, 2010 Apr 30;15(5):3260-9.

PMID: 20657475 DOI: 10.3390/molecules15053260

A series of new mesogenic azomethine diols were successfully synthesized by condensation reactions between various chloroalkanols and N,N'-bis(4-hydroxy)-benzylidene-o-toluidine (1). The structures of these compounds were confirmed by CHN, FT-IR, (1)H-NMR, and (13)C-NMR spectrophotometer. Their thermotropic liquid crystalline behavior was studied using differential scanning calorimetry (DSC) and polarizing optical microscope (POM). 4,4'-di(4-Hydroxybutoxy)-N-benzylidine-o-tolidine (2a) does not exhibit liquid crystalline properties. A nematic texture was observed for mesogenic diols 2b, and 2d, whereas the diol 2c exhibits a smectic mesophase. The increase of terminal alkyl chain in these mesogenic diols leads to a decrease in the transition temperature.

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