Antimicrobial activity and cytotoxicity of the ethanol extract, fractions and eight compounds isolated from Eriosema robustum (Fabaceae)

BMC Complementary and Alternative Medicine

Jacobus N Eloff²  Michael Spiteller¹  Pierre Tane³  Roukayatou Mbouangouere³  Sebastian Gottfried¹  Lyndy J McGaw²  Maurice D Awouafack³ 

[1] Institut für Umweltforschung (INFU) der Fakultät Chemie, Lehrstuhl für Umweltchemie und Analytische Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, D-44221 Dortmund, Germany;Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa;Laboratory of Natural Products Chemistry, Department of Chemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon

关键词: Cytotoxicity;    Antimicrobial;    Flavonoids;    Fabaceae;    Eriosema robustum;   

Others  :  1220867
DOI  :  10.1186/1472-6882-13-289

 received in 2013-04-27, accepted in 2013-10-25,  发布年份 2013

【 摘 要 】

Background

The aim of this study was to evaluate the antimicrobial activity and the cytotoxicity of the ethanol crude extract, fractions and isolated compounds from the twigs of Eriosema robustum, a plant used for the treatment of coughs and skin diseases.

Methods

Column chromatographic and spectroscopic techniques were used to isolate and identify eight compounds, robusflavones A (1) and B (2), orostachyscerebroside A (3), stigmasterol (4), 1-O-heptatriacontanoyl glycerol (5), eicosanoic acid (6), 3-O-β-D-glucopyranoside of sitosterol (7) and 6-prenylpinocembrin (8), from E. robustum. A two-fold serial microdilution method was used to determine the minimum inhibitory concentration (MIC) against fungi and bacteria, and the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide reduction assay was used to evaluate the cytotoxicity.

Results

Fraction B had significant antimicrobial activity against Aspergillus fumigatus and Cryptoccocus neoformans (MIC 0.08 mg/ml), whilst the crude extract and fraction A had moderate activity against A. fumigatus and Candida albicans (MIC 0.16 mg/ml). Fraction A however had excellent activity against Staphylococcus aureus (MIC 0.02 mg/ml), Enterococcus faecalis and Escherichia coli (MIC 0.04 mg/ml). The crude extract had significant activity against S. aureus, E. faecalis and E. coli. Fraction B had good activity against E. faecalis and E. coli (MIC 0.08 mg/ml). All the isolated compounds had a relatively weak antimicrobial activity. An MIC of 65 μg/ml was obtained with robusflavones A (1) and B (2) against C. albicans and A. fumigatus, orostachyscerebroside A (3) against A. fumigatus, and robusflavone B (2) against C. neoformans. Compound 8 had the best activity against bacteria (average MIC 55 μg/ml). The 3 fractions and isolated compounds had LC₅₀ values between 13.20 to > 100 μg/ml against Vero cells yielding selectivity indices between 0.01 and 1.58.

Conclusion

The isolated compounds generally had a much lower activity than expected based on the activity of the fractions from which they were isolated. This may be the result of synergism between different compounds in the complex extracts or fractions. The results support the traditional use of E. robustum to treat infections. The crude extract had a good activity and low preparation cost, and may be useful in topical applications to combat microbial infections.

【 授权许可】

   
2013 Awouafack et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 2.

【 参考文献 】

• [1]Ogungbamila O: Investigation of anti-infective activities of local plant materials used as drugs. In Results, lessons learned, and prospects for development of sustainable research environments in developing countries. Edited by Niemeyer HM. Santiago: IPICS; 1997.
• [2]Gillett JB, Polhill RM, Verdcourt B: Papilionoideae. In Flora of Tropical East Africa, Leguminosae. Part 4 edition. Edited by Milne-Redhead E, Polhill RM. London: Crown Agents for Overseas Governments and Administrations; 1971:635-637.
• [3]Kokwaro JO: Medicinal plants of East Africa. 3rd edition. Nairobi: University of Nairobi Press; 2009:335.
• [4]Awouafack MD, Tane P, Eloff JN: Two new antioxidant flavones from the twigs of Eriosema robustum (Fabaceae). Phytochemistry Lett 2013, 6:62-66.
• [5]Awouafack MD, Spiteller P, Lamshöft M, Kusari S, Ivanova B, Tane P, Spiteller M: Antimicrobial isopropenyl-dihydrofuranoisoflavones from Crotalaria lachnophora. J Nat Prod 2011, 74:272-278.
• [6]Awouafack MD, Kouam SF, Hussain H, Ngamga D, Tane P, Schulz B, Green IR, Krohn K: Antimicrobial prenylated dihydrochalcones from Eriosema glomerata. Planta Med 2008, 74:50-54.
• [7]Eloff JN: A sensitive and quick microplate method to determine the minimal inhibitory concentration of plant extracts for bacteria. Planta Med 1998, 64:711-713.
• [8]Masoko P, Picard J, Eloff JN: Antifungal activities of six South African Terminalia species (Combretaceae). J Ethnopharmacol 2005, 99:301-308.
• [9]Suleiman MM, McGaw LJ, Naidoo V, Eloff JN: Evaluation of several tree species for activity against the animal fungal pathogen Aspergillus fumigatus. S Afr J Bot 2010, 76:64-71.
• [10]Shai LJ, McGaw LJ, Masoko P, Eloff JN: Antifungal and antibacterial activity of seven traditionally used South African plant species active against Candida albicans. S Afr J Bot 2008, 74:677-684.
• [11]Mahlo SM, McGaw LJ, Eloff JN: Antifungal activity of leaf extracts from South African trees against plant pathogens. Crop Prot 2010, 29:1529-1533.
• [12]Eloff JN: Which extractant should be used for the screening and isolation of antimicrobial components from plants? J Ethnopharmacol 1998, 60:1-8.
• [13]Mosmann T: Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays. J Immunol Methods 1983, 65:55-63.
• [14]Zhang H, Oh J, Jang T, Min BS, Na M: Glycolipids from the aerial parts of Orostachys japonicus with fatty acid synthase inhibitory and cytotoxic activities. Food Chem 2012, 131:1097-1103.
• [15]Forgo P, Kövér KE: Gradient enhanced selective experiments in the 1H NMR chemical shift assignment of the skeleton and side-chain resonances of stigmasterol, a phytosterol derivative. Steroids 2004, 69:43-50.
• [16]Qi S-H, Zhang S, Huang J-S, Xiao Z-H, Wu J, Long L-J: Glycerol derivatives and sterols from Sargassum parvivesiculosum. Chem Pharm Bull 2004, 52:986-988.
• [17]Jain R, Sharma P, Bhagchandani T, Jain SC: Phytochemical investigation and antimicrobial activity of Acacia senegal root heartwood. J Pharm Res 2012, 5:4934-4938.
• [18]Al-Oqail M, Hassan WHB, Ahmad MS, Al-Rehaily AJ: Phytochemical and biological studies of Solanum schimperianum Hochst. Saudi Pharm J 2012, 20:371-379.
• [19]Caffaratti M, Ortega MG, Scarafia ME, Ariza Espinar L, Juliani HR: Prenylated flavanones from Dalea elegans. Phytochemistry 1994, 36:1082-1084.
• [20]Eloff JN: Quantification the bioactivity of plant extracts during screening and bioassay guided fractionation. Phytomedicine 2004, 11:370-371.
• [21]Kuete V: Potential of Cameroonian plants and derived products against microbial infections: a review. Planta Med 2010, 76:1479-1491.
• [22]Ríos JL, Recio MC: Medicinal plants and antimicrobial activity. J Ethnopharmacol 2005, 100:80-84.
• [23]Kuete V, Ango PY, Fotso GW, Kapche GDWF, Dzoyem JP, Wouking AG, Ngadjui BT, Abegaz BM: Antimicrobial activities of the methanol extract and compounds from Artocarpus communis (Moraceae). BMC Complement Altern Med 2011, 11:42. BioMed Central Full Text
• [24]Awouafack MD, Kusari S, Lamshöft M, Ngamga D, Tane P, Spiteller M: Semi-synthesis of dihydrochalcone derivatives and their in Vitro antimicrobial activities. Planta Med 2010, 76:640-643.
• [25]Lewis K, Ausubel FM: Prospects for plant derived antibacterials. Nat Biotechnol 2006, 24:1504-1507.
• [26]Eloff JN, Angeh I, McGaw LJ: A potentised leaf extract of Melianthus comosus has higher activity than six commercial products used against plant fungal pathogens. S Afr J Bot 2007, 73:286-287.
• [27]Eloff JN, Suleiman M, Naidoo V: A crude extract of Loxostylus alata is as effective in treating aspergillosis in poultry as a commercial drug. Planta Med 2010, 76:405.
• [28]Tanamatayarat P, Limtrakul P, Chunsakaow S, Duangrat C: Screening of some Rubiaceous plants for cytotoxic activity against Cervix Carcinoma (KB-3-1) Cell Line. Thai J Pharm Sci 2003, 27:167-172.
• [29]Caamal-Fuentes E, Torres-Tapia LW, Simá-Polanco P, Peraza-Sánchez SR, Moo-Puc R: Screening of plants used in Mayan traditional medicine to treat cancer-like symptoms. J Ethnopharmacol 2011, 135:719-724.
• [30]Eloff JN: A proposal on expressing the antibacterial activity of plant extracts - a small first step in applying scientific knowledge to rural primary health care in South Africa. S Afr J Sci 2000, 96:116-118.
• [31]Eloff JN, Famakin JO, Katerere DRP: Combretum woodii (Combretaceae) leaf extracts have high activity against Gram-negative and Gram-positive bacteria. Afr J Biotechnol 2005, 4:1161-1166.