Investigation of total phenolic content and antioxidant activities of Azadirachta indica roots

Document Type: Original Research Article


Department of Pharmacy, Noakhali Science and Technology University, Sonapur, Noakhali-3814, Bangladesh


Objective: The present study was an attempt to study total phenolic content and antioxidant property of the crude ethanolic extract of the roots of Azadirachta indica (A. indica).
Materials and Methods: To evaluate the antioxidant properties of the crude extract, some complementary test systems, namely DPPH free radical scavenging assay, reducing power assay, and ferrous ion chelating ability and determination of total phenolic content were conducted.
Results: In DPPH free radical scavenging test, IC50 value of the crude extract was found to be fairly significant (13.81±0.06 μg/ml) while compared with that of the reference standards, ascorbic acid and BHA (2.12±0.02 and 4.87±0.05 μg/ml, respectively). In reducing power assay, the maximum absorbance for the extract was found to be 1.523 ±0.026 at 100 μg/ml compared with standard ascorbic acid and BHA (2.811±0.013 μg/ml and 2.031±0.019 μg/ml, respectively). The IC50 value of the extract as percentage of Fe++ ion chelating ability was determined as 19.01±0.024 μg/ml where EDTA showed 8.87±0.035 μg/ml. The total phenolic amount was also calculated quite high in the extract (238.81±0.98 mg/g of gallic acid equivalent).
Conclusion: The assays showed the presence of significant antioxidant properties of the crude sample, which would justify its traditional use. However, it would be very interesting to investigate the possible causes and their mechanisms responsible for the antioxidant property of the plant A. indica.


Amin MN, Dewan SMR, Noor W, Shahid-Ud-Daula AFM. 2013. Characterization of chemical groups and determination of total phenolic content and in-vitro antioxidant activities of ethanolic extract of Ocimum sanctum leaves growing in Bangladesh. Euro J Exp Bio, 3: 449-454.

Anon; The Wealth of India: a dictionary of Indian raw material and industrial products. 1985. New Delhi, CSIR.

Chang ST, Wu JH, Wang SY, Kang PL, Yang NS, Shyur LF. 2001. Antioxidant activity of extracts from Acacia confusa bark and heartwood. J Agric Food Chem, 49: 3420-3424.

Dehpour AA, Ebrahimzadeh MA, Nabavi SF, Nabavi SM. 2009. Antioxidant activity of methanol extract of Ferula assafoetida and its essential oil composition. Grasas Aceites, 60: 405-412.

Dinis TC, Madeira VM, Almeida LM.  1994. Action of phenolic derivatives (acetaminophen, salicylate, and 5-amino salicylate) as inhibitors of membrane lipid peroxidation and as peroxyl radical scavengers. Arch Biochem Biophys, 315: 161-169.

Duh PD. 1994. Scavenging effect of methanolic extracts of peanut hulls on free-radical and active oxygen species. J Agric Food Chem, 42: 629-632.

Harini R, Sindhu S, Sagadevan E, Arumugam P. 2012.Characterization of in vitro antioxidant potential of Azadirachta indica and Abutilon indicum by different assay methods. J Pharm Res, 5: 3227-3231.

Hong H, Liu G. 2004. Protection against hydrogen peroxideinduced cytotoxicity in PC12 cells by scutellarin. Life Sci, 74: 2959-2973.

Kiranmai M, CB MK, Ibrahim M. 2011. Free radical scavenging activity of neem tree (Azadirachta indica a. Juss var., Meliaceae) root bark extract. Asian J Pharm Clin Res, 4: 134-136.

Saikat S, Chakraborty R, Sridhar C, Reddy YS, Biplab D. 2010. Free radicals, antioxidants, diseases and phytomedicines: current status and future prospect. Int J Pharm Sci Rev Res, 3: 91-100.

Tanaka M, Kuie CW, Nagashima Y, Taguchi T. 1988. Applications of antioxidative Maillard reaction products from histidine and glucose to sardine products. Nippon Suisan Gakkaishi, 54: 1409-1414.

Wolfe K, Wu X, Liu RH.  2003. Antioxidant activity of apple peels. J Agric Food Chem, 51: 609-614.