MyMedR

A note on (+)-catechin

Wiart C

Nutr Res, 2015 Jun;35(6):545.

PMID: 25957969 DOI: 10.1016/j.nutres.2015.04.014

A note on Toxicodendron vernicifluum (Stokes) F.A. Barkley

Wiart C

Food Chem Toxicol, 2014 Feb;64:410.

PMID: 24316313 DOI: 10.1016/j.fct.2013.11.052

Goniothalamus species: a source of drugs for the treatment of cancers and bacterial infections?

Wiart C

Evid Based Complement Alternat Med, 2007 Sep;4(3):299-311.

PMID: 17965760

Irrespective of the presence of cytotoxic acetogenins and styryl-lactones in the genus Goniothalamus, only 22 species in the genus Goniothalamus, out of 160 species (13.7%) have so far been investigated. In an effort to promote further research on the genus Goniothalamus which could represent a source of drugs for the treatment of cancers and bacterial infections, this work offers a broad analysis of current knowledge on Goniothalamus species. Therefore, it includes (i) taxonomy (ii) botanical description (iii) traditional medicinal uses and (iv) phytochemical and pharmacological studies. We discuss the molecular mechanisms of actions of acetogenins and styryl-lactones, with some emphasis on the possible involvement of protein kinase, Bax and TRAIL receptors in the cytotoxic effects of styryl-lactones. We also report (v) the growth inhibition of several nosocomial bacteria by Goniothalamus. scortechinii. The crude methanol extract of G. scortechinii showed a good and broad spectrum of antibacterial activity against both Gram-negative and Gram-positive bacteria.

Fulltext The Medicinal Timber Canarium patentinervium Miq. (Burseraceae Kunth.) Is an Anti-Inflammatory Bioresource of Dual Inhibitors of Cyclooxygenase (COX) and 5-Lipoxygenase (5-LOX)

Mogana R, Teng-Jin K, Wiart C

ISRN Biotechnol, 2013;2013:986361.

PMID: 25937987 DOI: 10.5402/2013/986361

The barks and leaves extracts of Canarium patentinervium Miq. (Burseraceae Kunth.) were investigated for cyclooxygenase (COX) and 5-lipoxygenase (LOX) inhibition via in vitro models. The corresponding antioxidative power of the plant extract was also tested via nonenzyme and enzyme in vitro assays. The ethanolic extract of leaves inhibited the enzymatic activity of 5-LOX, COX-1, and COX-2 with IC50 equal to 49.66 ± 0.02 μg/mL, 0.60 ± 0.01 μg/mL, and 1.07 ± 0.01 μg/mL, respectively, with selective COX-2 activity noted in ethanolic extract of barks with COX-1/COX-2 ratio of 1.22. The ethanol extract of barks confronted oxidation in the ABTS, DPPH, and FRAP assay with EC50 values equal to 0.93 ± 0.01 μg/mL, 2.33 ± 0.02 μg/mL, and 67.00 ± 0.32 μg/mL, respectively, while the ethanol extract of leaves confronted oxidation in β-carotene bleaching assay and superoxide dismutase (SOD) assay with EC50 value of 6.04 ± 0.02 μg/mL and IC50 value of 3.05 ± 0.01 μg/mL. The ethanol extract acts as a dual inhibitor of LOX and COX enzymes with potent antioxidant capacity. The clinical significance of these data is quite clear that they support a role for Canarium patentinervium Miq. (Burseraceae Kunth.) as a source of lead compounds in the management of inflammatory diseases.

Fulltext Anti-Inflammatory, Anticholinesterase, and Antioxidant Potential of Scopoletin Isolated from Canarium patentinervium Miq. (Burseraceae Kunth)

Mogana R, Teng-Jin K, Wiart C

Evid Based Complement Alternat Med, 2013;2013:734824.

PMID: 23878606 DOI: 10.1155/2013/734824

Bioassay guided fractionation of an ethanol extract of leaves of Canarium patentinervium Miq. (Burseraceae Kunth.) led to the isolation of scopoletin. The structure of this coumarin was elucidated based on spectroscopic methods including nuclear magnetic resonance (NMR-1D and 2D) and mass spectrometry. Scopoletin inhibited the enzymatic activity of 5-lipoxygenase and acetyl cholinesterase with an IC50 equal to 1.76 ± 0.01 μ M and 0.27 ± 0.02 mM, respectively, and confronted oxidation in the ABTS, DPPH, FRAP, and β -carotene bleaching assay with EC50 values equal to 5.62 ± 0.03 μ M, 0.19 ± 0.01 mM, 0.25 ± 0.03 mM and 0.65 ± 0.07 mM, respectively. Given the aforementioned evidence, it is tempting to speculate that scopoletin represents an exciting scaffold from which to develop leads for treatment of neurodegenerative diseases.

Fulltext In Vitro Antimicrobial, Antioxidant Activities and Phytochemical Analysis of Canarium patentinervium Miq. from Malaysia

Mogana R, Teng-Jin K, Wiart C

Biotechnol Res Int, 2011;2011:768673.

PMID: 21776395 DOI: 10.4061/2011/768673

Six different extracts of Canarium patentinervium Miq. (Burseraceae) leaves and barks were screened for their phytochemical composition, and antimicrobial and free radical scavenging activities. Among the different extracts tested, the ethanol extract of leaves showed significant antimicrobial and radical scavenging activities. The most susceptible micro-organisms were found to be Gram-positive bacteria (Staphylococcus aureus, methicillin-resistant Staphylococcus aureus or MRSA) and Gram-negative bacteria (Pseudomonas aeruginosa). Phytochemical analysis of the extracts revealed that the antimicrobial and the radical scavenging activities are mainly due to the presence of tannins and flavonoids. The results obtained suggest that Canarium patentinervium Miq. could be exploited in the management of various infectious diseases.

Growth inhibition of foodborne and nosocomial pathogens by aqueous fraction of bearded Argostemma (Argostemma involucratum Hemsl., Rubiaceae)

Wiart C, Hannah A, Yusof M, Hamimah H, Sulaiman M

J Herb Pharmacother, 2005;5(3):97-102.

PMID: 16520301

The crude methanol extract of Bearded Argostemma (Argostemma involucratum Hemsl., Rubiaceae) showed a good and broad spectrum of antibacterial activity against both Gram-negative and Gram-positive bacteria. The activity was increased on fractionation (hexane, dichloromethane and water), particularly in the aqueous fraction which was more active than the methanol extract and streptomycin (no activity was shown against tested moulds). Both the hexane and dichloromethane fractions were inactive. The objective of this experiment was to investigate the antibacterial activity of hexane, dichloromethane, and aqueous fractions of Argostemma involucratum Hemsl. The aqueous fraction of Bearded Argostemma may be a possible new option for the treatment of bacterial infections.

Antimicrobial activity of Acalypha siamensis Oliv. ex Gage

Wiart C, Hannah A, Yassim M, Hamimah H, Sulaiman M

J Ethnopharmacol, 2004 Dec;95(2-3):285-6.

PMID: 15507350

The hexane, dichloromethane, ethyl acetate and methanol fractions of leaves of Acalypha siamensis Oliv. ex Gage were evaluated for antibacterial and antifungal activity. The antibacterial activity was more pronounced in the ethyl acetate and methanol extracts. No activity was shown against tested moulds.

Fulltext The antiacetylcholinesterase and antileishmanial activities of Canarium patentinervium Miq

Mogana R, Adhikari A, Debnath S, Hazra S, Hazra B, Teng-Jin K, et al.

Biomed Res Int, 2014;2014:903529.

PMID: 24949478 DOI: 10.1155/2014/903529

In continuation of our natural and medicinal research programme on tropical rainforest plants, a bioassay guided fractionation of ethanolic extract of leaves of Canarium patentinervium Miq. (Burseraceae Kunth.) led to the isolation of scopoletin (1), scoparone (2), (+)-catechin (3), vomifoliol (4), lioxin (5), and syringic acid (6). All the compounds exhibited antiacetylcholinesterase activity with syringic acid, a phenolic acid exhibiting good AChE inhibition (IC50 29.53 ± 0.19 μ g/mL). All compounds displayed moderate antileishmanial activity with scopoletin having the highest antileishmanial activity (IC50 163.30 ± 0.32 μ g/mL). Given the aforementioned evidence, it is tempting to speculate that Canarium patentinervium Miq. represents an exciting scaffold from which to develop leads for treatment of neurodegenerative and parasitic diseases.

Annonaceae: bio-resource for tomorrow's drug discovery

Aminimoghadamfarouj N, Nematollahi A, Wiart C

J Asian Nat Prod Res, 2011 May;13(5):465-76.

PMID: 21534046 DOI: 10.1080/10286020.2011.570265

One of the rich sources of lead compounds is the Angiosperms. Many of these lead compounds are useful medicines naturally, whereas others have been used as the basis for synthetic agents. These are potent and effective compounds, which have been obtained from plants, including anti-cancer (cytotoxic) agents, anti-malaria (anti-protozoal) agents, and anti-bacterial agents. Today, the number of plant families that have been extensively studied is relatively very few and the vast majorities have not been studied at all. The Annonaceae is the largest family in the order Magnoliales. It includes tropical trees, bushes, and climbers, which are often used as traditional remedies in Southeast Asia. Members of the Annonaceae have the particularity to elaborate a broad spectrum of natural products that have displayed anti-bacterial, anti-fungal, and anti-protozoal effects and have been used for the treatment of medical conditions, such as skin diseases, intestinal worms, inflammation of the eyes, HIV, and cancer. These special effects and the vast range of variation in potent compounds make the Annonaceae unique from other similar families in the Magnoliales and the Angiosperms in general. This paper attempts to summarize some important information and discusses a series of hypotheses about the effects of Annonaceae compounds.

Antimicrobial activity of tiger's betel (Piper porphyrophyllum N.E. Br., Piperaceae)

Wiart C, Hannah NA, Yassim M, Hamimah H, Sulaiman M

Phytother Res, 2004 Sep;18(9):783-4.

PMID: 15478188

The ethanol extract of leaves of Piper porphyrophyllum N.E. Br. showed a broad spectrum of antibacterial activity. The activity was increased on fractionation (hexane, dichloromethane and aqueous), particularly in the aqueous fraction. No activity was shown against tested Candida albicans.

Fulltext Antibacterial activities of the extracts, fractions and isolated compounds from Canarium patentinervium Miq. against bacterial clinical isolates

Mogana R, Adhikari A, Tzar MN, Ramliza R, Wiart C

BMC Complement Med Ther, 2020 Feb 14;20(1):55.

PMID: 32059725 DOI: 10.1186/s12906-020-2837-5

BACKGROUND: Canarium patentinervium leaves are used by the local indigenous people of Malaysia for wound healing. The current study is undertaken to screen the comprehensive antibacterial activity of the leaves and barks extracts, fractions and isolated compounds from this plant. Bioassay guided fractionation was also undertaken to deeply evaluate the antibacterial activity of the water fraction of the leaves extract. This is to provide preliminary scientific evidence to the ethnopharmacology usage of this plant by investigating antibacterial properties of the plant and its isolated constituents.

METHODS: Bio-assay guided fractionation and subsequent isolation of compounds using open column chromatography. The antibacterial activity against gram positive and gram negative ATCC strain and resistant clinical strains were evaluated using microtiter broth dilution method to determine minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time-kill assay. The chemical structure of the isolated compounds from the water fraction of the ethanol extract of leaves was elucidated using Nuclear Magnetic Resonance (NMR).

RESULTS: The ethanol extract of the leaves and barks showed antimicrobial activity against all four ATCC and eight clinical isolates. The ethanol extract of the leaves and the corresponding water fraction had good activity against MRSA S. aureus. (MIC: 250 μg/ml) and had bactericidal effect on eight of the clinical strains (MSSA,MRSA, oxacillin-resistant CONS, oxacillin-sensitive CONS, Enterococcus faecalis, Klebsiela species, Kleb pneumoniae ESBL and Candida parapsilosis). Further phytochemical investigation of the water fraction of the crude ethanol extract of leaves afforded compound 7 (hyperin) and compound 8 (cynaroside) that had bactericidal activity against tested bacterial species (MIC 50 μg/ml and 100 μg/ml). The two compounds were isolated from this genus for the first time.

CONCLUSIONS: These results may provide a rational support for the traditional use of Canarium patentinervium Miq. in infections and wound healing, since the antimicrobial compounds isolated were also present in the leaves extract.

Antibacterial alkaloids from Artabotrys crassifolius Hook.f. & Thomson

Tan KK, Khoo TJ, Rajagopal M, Wiart C

Nat Prod Res, 2015;29(24):2346-9.

PMID: 25738993 DOI: 10.1080/14786419.2015.1013954

Chloroform extract of bark of Artabotrys crassifolius Hook.f. & Thomson exhibited antibacterial activities against both American Type Culture Collection and clinical bacterial strains in vitro with zones of inhibition ranging from 7 to 14 mm. Further analysis of this extract yielded artabotrine, liridine, lysicamine and atherospermidine. Artabotrine displayed a broad array of antibacterial activity mostly against Gram-positive bacteria with minimum inhibitory concentration (MIC) values ranging from 1.25 μg/mL to 5 μg/mL. Of note, artabotrine, liridine and lysicamine are bactericidal against Gram-negative extended-spectrum beta-lactamase-producing Klebsiella with MIC values equal 2.5, 2.5 and 10 μg/mL, respectively, and minimum bactericidal concentrations values equal to 2.5, 5 and 20 μg/mL.

Antiviral properties of ent-labdene diterpenes of Andrographis paniculata nees, inhibitors of herpes simplex virus type 1

Wiart C, Kumar K, Yusof MY, Hamimah H, Fauzi ZM, Sulaiman M

Phytother Res, 2005 Dec;19(12):1069-70.

PMID: 16372376

Andrographolide, neoandrographolide and 14-deoxy-11,12-didehydroandrographolide, ent-labdene diterpenes isolated from Andrographis paniculata showed viricidal activity against herpes simplex virus 1 (HSV-1). None of these compounds exhibited significant cytotoxicity at viricidal concentrations.

Fulltext High Correlation of 2,2-diphenyl-1-picrylhydrazyl (DPPH) Radical Scavenging, Ferric Reducing Activity Potential and Total Phenolics Content Indicates Redundancy in Use of All Three Assays to Screen for Antioxidant Activity of Extracts of Plants from the Malaysian Rainforest

Clarke G, Ting KN, Wiart C, Fry J

Antioxidants (Basel), 2013;2(1):1-10.

PMID: 26787618 DOI: 10.3390/antiox2010001

Extracts of plants from the Malaysian rainforest and other fragile habitats are being researched intensively for identification of beneficial biological actions, with assessment of antioxidant behavior being a common component of such assessments. A number of tests for antioxidant behavior are used, with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reduction activity potential (FRAP) assays often being used in parallel, and also with measurement of total phenolics content (TPC) as a surrogate marker for antioxidant capacity. The present study investigated the possible redundancy in using all three assays to determine antioxidant capacity in 92 extracts obtained from 27 plants from the Malaysian rainforest. The results demonstrated that the assays displayed a high (R ≥ 0.82) and significant (P < 0.0001) correlation with one another, indicating a high level of redundancy if all three assays are used in parallel. This appears to be a waste of potentially valuable plant extracts. Because of problems with the FRAP assay relating to color interference and variable rates of reaction point, the DPPH assay is the preferred assay in preliminary screening of extracts of plants from the Malaysian rainforest.

Sesquiterpenes and alkaloids from Scorodocarpus borneensis

Wiart C, Martin MT, Awang K, Hue N, Serani L, Laprévote O, et al.

Phytochemistry, 2001 Oct;58(4):653-6.

PMID: 11576617

A new sesquiterpene, scodopin, and a mixture of three tryptamine-type alkaloids, scorodocarpines A-C, were isolated from the fruits of Scorodocarpus borneensis, together with a known hemisynthetic sesquiterpene, cadalene-beta-carboxylic acid, which was isolated from the bark. The structures of the new compounds were elucidated by interpretation of spectral data, especially tandem mass spectrometry for the alkaloid mixture.

Antimicrobial screening of plants used for traditional medicine in the state of Perak, Peninsular Malaysia

Wiart C, Mogana S, Khalifah S, Mahan M, Ismail S, Buckle M, et al.

Fitoterapia, 2004 Jan;75(1):68-73.

PMID: 14693223

Seventy-two extracts (methanol) obtained from the leaves, barks, and roots of 50 plant species used in the traditional medicine of Perak, Peninsular Malaysia, have been screened for antibacterial and antifungal activities. Peristrophe tinctoria, Polyalthia lateriflora, Knema malayana, Solanum torvum, Celosia argentea, Eclipta prostrata, Ancistrocladus tectorius, Dillenia suffruticosa, Piper stylosum and Rafflesia hasseltii displayed the broadest spectrum of activity.

Activity of Pericampylus glaucus and periglaucine A in vitro against nasopharangeal carcinoma and anti-inflammatory activity

Shipton FN, Khoo TJ, Hossan MS, Wiart C

J Ethnopharmacol, 2017 Feb 23;198:91-97.

PMID: 28049063 DOI: 10.1016/j.jep.2016.12.045

ETHNOPHARMACOLOGICAL RELEVANCE: Pericampylus glaucus is a climbing plant found across Asia and used in traditional medicine to treat a number of conditions including splenomegaly, fever, cough, laryngitis, pulmonary disease, asthma, headache, hair loss, snake bite, boar bite, factures, boils, tumours, tetanus, rheumatic pain, itches and eclampsia.

AIM OF THE STUDY: To test extracts of P. glaucus in a number of bioassays and determine the legitimacy of its traditional use.

MATERIALS AND METHODS: The stems, leaves, roots and fruits of P. glaucus were collected and extracted sequentially with hexane, chloroform and ethanol, respectively. The anti-inflammatory activity was assessed by testing the ability of the extracts to inhibit heat induced protein denaturation, stabilise human red blood cells under hypotonic stress and by testing the inhibitory activity of the extracts against cyclooxygenases 1 and 2. Cytotoxicity was tested using the human lung epithelial cell line MRC-5 and nasopharangeal carcinoma cell line HK1 in the MTT assay.

RESULTS: Many of the samples showed an ability to prevent heat induced protein denaturation, as well as prevent lysis of red blood cells. Most of the extracts demonstrated inhibitory activity towards both of the COX enzymes. The ethanol extracts tended to demonstrate greater toxicity than other extracts, with some of the other extracts significantly enhancing growth and metabolism of the cells.

CONCLUSION: The benefit of P. glaucus for the treatment of diseases related to inflammation and cancer was supported by the in vitro assays adopted in this study.

The rainforest of Southeast Asia, particularly Malaysia, is endowed with several medicinal plants species

Wiart C, Akaho E, Hannah M, Yassim M, Hamimah H, Au TS, et al.

Am J Chin Med, 2005;33(4):683-5.

PMID: 16173541

Antioxidant and cytoprotective effects of an ethanol extract of Acalypha wilkesiana var. macafeana from Malaysia

Din WM, Chu J, Clarke G, Jin KT, Bradshaw TD, Fry JR, et al.

Nat Prod Commun, 2013 Mar;8(3):375-80.

PMID: 23678815

In the annals of biomedical theory perhaps no single class of natural product has enjoyed more ingenious speculation than antioxidants formally aimed at counteracting oxidative insults which are involved in the pathophysiology of Alzheimer's and Parkinson's disease, cancer, amyotrophic lateral sclerosis, skin ageing and wound healing. In pursuing our study of Malaysian traditional medicines with antioxidant properties, we became interested in Acalypha wilkesiana var. macafeana hort., used traditionally to heal wounds. To examine whether Acalypha wilkesiana var. macafeana hort. could suppress oxidation an ethanol extract was tested by conventional chemical in vitro assays i.e., ferric reducing antioxidant potential assay (FRAP), DPPH scavenging assay and beta-carotene bleaching (BCB) assay. To explore whether Acalypha wilkesiana var. macafeana hort. protected cells against oxidative injuries, we exposed human hepatocellular liver carcinoma (HepG2) cells to tert-butylhydroperoxide (t-BHP). In all the aforementioned experiments, the ethanol extracts elicited potent antioxidant and cytoprotective activities. To gain a better understanding of the phytochemical nature of the antioxidant principle involved, five fractions (F1-F5) obtained from the ethanol extract were tested using FRAP, DPPH and BCB assays. Our results provided evidence that F5 was the most active fraction with antioxidant potentials equal to 2.090 +/- 0.307 microg/mL, 0.532 +/- 0.041 microg/mL, 0.032 +/- 0.025 microg/mL in FRAP, DPPH and BCB assay, respectively. Interestingly, F5 protected HepG2 against t-BHP oxidative insults. To further define the chemical identity of the antioxidant principle, we first performed a series of phytochemical tests, followed by liquid-chromatography and mass spectrometry (LC/MS) profiling which showed that the major compound contained in F5 was geraniin. To the best of our knowledge, this is the first report showing that the wound healing property of Acalypha wilkesiana var. macafeana hort. is mediated by a geraniin containing extract. Furthermore, our data leads us to conclude that geraniin could be used as a potential pharmaceutical and/or cosmetic topical agent.

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