[01] Stanley Irobekhian Reuben Okoduwa, Directorate of Research and Development, Nigerian Institute of Leather and Science Technology, Zaria, Nigeria. [02] Oche Okpe, Department of Biochemistry, Federal University of Agriculture, Makurdi, Nigeria. [03] Ugochi Judith Okoduwa, Petrochemicals and Allied Department, National Research Institute for Chemical Technology, Zaria, Nigeria. [04] Bernard Egwu Igiri, Directorate of Research and Development, Nigerian Institute of Leather and Science Technology, Zaria, Nigeria. [05] Daniel Hassan Mhya, Department of Biochemistry, College of Medical Sciences, Abubakar Tafawa Balewa University, Bauchi, Nigeria. [06] Lovina Okon Mbora, Directorate of Science Laboratory Technology, Nigerian Institute of Leather and Science Technology, Zaria, Nigeria.

The economical extraction of large amount of specific phytoconstituents with a smaller quantity of solvent requires a simple and safe technique, since extraction is one of the most significant stages in the discovery of new active drug-candidate. This study investigated the phytochemical contents of two medicinal plants, extracted using different extraction methods. Twenty grams of Vernonia amygdalina (VA) and Ocimum gratissimum (OG) leaves were extracted with three different extraction methods (maceration, Soxhlet and microwave) using methanol. The yield and phytochemical contents were compared. The results showed that the percentage recovery yield of phytochemical content was significantly (p<0.05) higher in the extracts obtained from microwave method (20.55%), when compared to the Soxhlet (18.55%) and maceration technique (15.60%). The extracts obtained from microwave extraction protocol had significantly (p<0.05) higher concentrations in phenolics, saponins and tannins. Soxhlet extraction gave extract with significantly (p<0.05) higher yield on alkaloid, while the extract from maceration was higher in flavonoids. This study showed that the concentration of specific phytoconstituents obtained from medicinal plants depends on the extraction method. The results from this study suggest that Soxhlet technique is best for extraction of alkaloid, maceration technique for flavonoids and microwave assisted extraction technique for phenolics, saponins and tannins.

Medicinal Plants, Phytochemical, Vernonia amygdalina, Ocimum gratissimum, Microwave Extraction, Soxhlet, Maceration

[01] World Health Organization (WHO). International cardiovascular disease statistics, Pp. 7-8. 2006. [02] Huie CW. A review of modern sample-preparation techniques for the extraction and analysis of medicinal plants. Anal. Bioanal. Chem. 2002; 373: 23-30. [03] Loudon, Irvine. Western Medicine: An Illustrated History. Oxford University Press. p. 54. ISBN 9780199248131. 2002. [04] Lichterman BL. "Aspirin: The Story of a Wonder Drug". Bri. Med. J. 2004; 329 (7479): 1408. Doi: 10.1136/bmj.329.7479.1408. [05] Sumner, Judith. Natural His. Med. Plants. Timber Press. p. 16. 2000. ISBN 0-88192-483-0. [06] Odugbemi T. Outline Med. Plants Nig. 1st Edition, University of Lagos Press, Nigeria, p. 77. 2006. [07] Sweeney CJ, Mehrotra S, Sadaria MR, Kumar S. The sequiterprene lactone parthenolide in combination with docetaxel reduces metastasis and improves survival in a xenograft Van-model of breast cancer: Mole. Cancer Ther. 2005; 4 (6): 1004. [08] Ijeh II, Ejike CECC. Current perspective on the medicinal potential of Vernonia amygdalina Del. J. Med. Plant Res. 2011; 5 (7): 1051-1061. [09] Jucelia BS, Vanessa ST, Carolina MG. Vernonia condensata Baker Asteraceae: A promising source of antioxidant. Oxidative Medicine and Cellular Longevity. 2013; Article ID 698018. doi: 10.1155/2013/698018. [10] Van-Burden TP, Robinson WC. Formation of Complexes between protein and tannin acid. J. Agric. Food Chem., 1981; 1: 17. [11] Okpe O, Habila N, Ikwebe J, Upev VA, Okoduwa SIR, Omiagbocho TI. Antimalarial potential of Carica papaya and Vernonia amygdalina in mice infected with Plasmodium berghei. J. Trop. Med.. 2016, 2016, Pp 6 http://dx.doi.org/10.1155/2016/8738972 [12] Blanco JG, Gil RR, Bocco JL, Meragelman TL, Genti Raimondi S, Flurry A. Aromatic Inhibition by an 11, 13- Dihydroderivative of a Sesquiterpene Lactone. J. Pharmacol Exp. Ther. 2001; 297 (3): 1099. [13] Misari WF. Review of medical physiology, 21 ed., McGraw Hill Inc. New York; pp. 316-318, 541. 1992. [14] Okoduwa SIR, Umar IA, James DB, Inuwa HM. Validation of the antidiabetic effects of Vernonia amygdalina delile leaf fractions in fortified diet-fed streptozotocin-treated rat model of Type-2 diabetes. J. Diabetol, 2017; 8: 3. [15] Yedjou C, Izevbigie E, Tchounwou P. Preclinical assessment of Vernonia amygdalina leaf extract as DNA damaging anti-cancer agent in the management of breast cancer. Dec., 1st ed. Inter. J. Environ. Res. Public Health. 2011. [16] Aveen NA. Comparative extraction methods, phytochemical constituents, fluorescence analysis and HPLC validation of rosmarinic acid content in Mentha piperita, Mentha longifolia and Ocimum basilicum. J. Pharmacog. Phytochem. 2015; 3 (16): 130-139. [17] Okoduwa SIR, Umar IA, James DB, Inuwa HM. Anti-diabetic potential of Ocimum gratissimum leaf fractions in fortified diet-fed streptozotocin-treated rat model of Type-2 diabetes. Medicines, 2017; 4.(4): 73. doi: 10.3390/medicinees4040073. [18] Bonsi V, Chavan BM. Plant Foods Hum. Nutr. 1998; 38 (2): 189-197. [19] Sofowora A. Medicinal plants and traditional medicine in Africa. 3rd ed. Spectrum books Limited, Ibadan, pg 172-188. 1999. [20] Edeoga HO, Okwu DE, Mbaebie BO. Phytochemical constituents of some Nigerian medicinal plants. Afri. J. Biotech. 2005; 4: 685–688. [21] Abo KA, Ogunleye VO, Ashidi JS. Antimicrobial potential of Spondias mombin, Croton zambesicus and Zygotritonia crocea. J. Pharm. Res. 1991; 5 (13): 494-497. [22] Anne EG, Colin DW, Masanaru M. Extraction of alkaloids of Catharanthus roseus tissue. 1998; US patent 4831133. [23] Azwanida NN. A review on the extraction methods use in medicinal plants. principles, strength and limitation. Medicinal Aromatic Plants. 2015; 4: 196. [24] Jensen WB. The origin of the soxhlet extractor. Journal of Chemical Education. 2007; 84 (12) 1913 pages. [25] Evans P, Kamaran A. Pharmacognostic studies on Plant Extracts. 1996; 3: 84-89. [26] Harborne JB. Phytochemical Methods, Chapman and Hall Limited., London, pp. 49-188. 1973. [27] Bohm BA, Kocipai-Abyazan R. Flavonoid and condensed Tannins from leaves of Hawaiian vaccinium vaticulatum and V. calycinium. Pacific Sci. 1994; 48: 458-463. [28] Obadoni BO, Ochuko PO. Phytochemical studies and comparative efficacy of the crude extracts of some homeostatic plants in Edo and Delta States of Nigeria. Glob. J. Pre Appl. Sci., 86: 2001. [29] Tatke, P. and Jaiswal, Y. (2011). An overview of Microwave Assisted Extraction and its Applications in Herbal Drugs Research, Research Journal of Medicinal Plant, 5 (1): 21-31. [30] Okoduwa SIR, Umar IA, James DB, Habila JD. Evaluation of extraction protocols for anti-diabetic phytochemical substances from medicinal plants. World J. Diabetes. 2016; 7 (20): 605 -614. [31] Hossain MA, AL-Raqmi KAS, AL-Mijizy ZH, Weli AM, Al-Riyami Q. Study of total phenol, flavonoids contents and phytochemical screening of various leaves crude extracts of locally grown Thymus vulgaris. Asian Pac. J. Trop. Biomedicine. 2013; 3 (9): 705-710. [32] Dadzie JB. Antidiabetic Effect of Young and Old Ethanolic Leaf Extracts of Vernonia amygdalina: A Comparative Study. J. Diab. Research. 2016, Article ID 8252741, 13 pages. http://dx.doi.org/10.1155/2016/8252741 [33] Proestos C, and Komaitis M. (2008). Application of microwave assisted extraction to the fast extraction of plant phenolic compounds. LWT-Food Science and Technology, 41, 652e659. Pub. British Medicine Bulletin, 49: 479-724. [34] Hao, J. Y., Han, W., Huang, S. D., Xue, B. Y. and Deng, X. (2002). Microwave assisted extraction of artemisinin from Artemisia annua L. Separation and Purification Technology. 28 (3): 191-196. [35] Chan, C. H., Yusoff, R., Ngoh, G. C. and Kung, F. W. (2011). Extraction of anti-diabetic active ingredient, quercetin from herbal plant using microwave-assisted extraction (MAE) technique, International conference on Materials for Advanced Technologies. SUNTEC Singapore, 1: 2-5. [36] Dai, J., Yaylayan, V. A., Raghavan, G. V. and Parè, J. R. (1999). Extraction and colorimetric determination of azadirachtin-related limonoids in neem seed kernel. Journal of Agricultural and Food Chemistry, 47 (9): 3738-3742. [37] Pan, Y., Wang, K., Huang, S., Wang, H., Mu, X., He, C.,... Huang, F. (2008). Antioxidant activity of microwave-assisted extract of longan (Dimocarpus Longan Lour.) peel. Food Chemistry, 106 (3): 1264-1270. [38] Ramamoorthy D, Bilal A, Bashir A. A preliminary Phytochemical Screening and evaluation of analgesic activity of methanolic extract of Vernonia amygdalina. Int. J. Pharm Sci. 2011; 3 (4): 164-166. [39] Pragada RR, Vangepurapu V, Ethadi SR. Phytochemical investigation of different fractions of Ocimum gratissimum. Int. J. Pharm Sci. 2011; 3 (4): 314-317. [40] Kumudhavalli MV, Jaykay B. Pharmacological Screening on Leaves of the Plant of Hemionitis Arifolia (Burm). J Pharm Res., Bio Chem Sci. 2012; 3 (2): 79-83. [41] Muraleedharannair M, Johnson M, Mony M, Zachariah M, Solomon J. Inter-specific variation studies on the phytoconstituents of Christella and Adiantum using phytochemical methods; As. Paci J. Tro. Biomed. 2012; s40-s45. [42] Kunda G, Rajukar N. Evaluation of phytochemicals, antioxidant activity and elemental content of Adiantum capillus veneris leaves. J. Chem. Pharm. Res. 2002; 4 (1): 365-374.