DETERMINATION OF TOTAL PHENOLIC AND FLAVONOID CONTENTS, ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF SOME IMPORTANT SALEP ORCHIDS
Abstract
ABSTRACT
In this study we evaluated the secondary metabolites, total phenolic (TPC) and flavonoid contents (TFC), antioxidant and antimicrobial activities of salep orchids, Anacamptis morio, Anacamptis pyramidalis, Neotinea tridentata, Ophrys mammosa, Ophrys lutea, and Ophrys speculum. DPPH free radical scavenging assay was used to determine the antioxidant activities of n-hexane, chloroform, methanol and water extracts of the plants. The antimicrobial activities were also determined by the Broth micro-dilution method. The extracts were studied for antimicrobial activity by the Minimum Inhibitory Concentration (MIC) approach against seven clinical pathogenic bacteria and two fungi. Phytochemical screening revealed that the presences of coumarins, flavonoids, flavanones, cardiac glycosides, proteins and quinones. The extracts had variable TPC and TFC, with values of 4.46 ± 0.19–45.83 ± 1.86 mg gallic acid equivalent/g dry weight and 0.67 ± 0.04–8.64 ± 0.37 mg quercetin equivalent/g dry weight respectively. O. speculum had the highest (35.12%) antioxidant activity, followed by O. mammosa (33.17%). Chloroform extracts of all species showed significant antioxidant and antimicrobial activity. These bioactivities of the chloroform extracts were positively associated with the total phenolic and flavonoid contents. The MIC concentrations ranged from 0.156–20 mg/mL. The present investigation shows that the extracts of these species, especially chloroform extracts, could be used as potential antioxidant and antimicrobial sources.
Keywords
References
- [1] Dressler RL. Phylogeny and classification of the orchid family. Cambridge (UK): Cambridge University Press Publishers, 1994.
- [2] Bulpitt CJ. The uses and misuses of orchids in medicine. Occasional Paper. QJM 2005; 98:625-631.
- [3] Kreutz CAJ. Türkiye orkideleri (botanik özellikleri, ekolojik özellikleri, doğal yayılış alanları, yaşam tehditleri, koruma önlemleri). Turkey: Rota Yayınları, 2009. pp.848.
- [4] Sezik E, İşler S, Orhan Ç, Deniz Gİ, Güler N, Aybeke M, Üstün O. Salep ve orkidelerin tahribi. Ankara: TÜBİTAK. Project No: TBAG-Ç.SEK/23(103T008). 2007.
- [5] Flückiger FA, Hambury D. Pharmacographia. A history of the principal drugs of vegetable origin met with in Great Britain and British India. London: Macmillan, 1879.
- [6] Sezik E. Orkidelerimiz Türkiye’ nin orkideleri. Istanbul: Sandoz Kültür Yayınları, 1984.
- [7] Baytop T. Türkiye’ de bitkilerle tedavi: Geçmişte ve bugün. Istanbul: Nobel Tıp Kitapevleri, 1999. pp.480.
- [8] Jalal JS, Kumar P, Pangtey YPS. Ethnomedicinal orchids of Uttarakhand, Western Himalaya. Ethnobotanical Leaflets 2008; 12:1227-30.
- [9] Bulpitt J, Li Y, Bulpitt PF, Wang J. The use of orchids in Chinese medicine. JRSM 2007; 100(12):558-563.
- [10] Abah SE, Egwari LO. Methods of extraction and antimicrobial susceptibility testing of plant extracts. AJBAS 2011; 3(5):205-209.