Journal of Food Research; Vol. 2, No. 3; 2013 ISSN 1927-0887 E-ISSN 1927-0895 Published by Canadian Center of Science and Education 93 The Potential of Baobab (Adansonia digitata L.) Extracts as Biocontrol on the Growth and Aflatoxin Production by Aspergillus flavus and A. parasiticus Saifeldin A. F. El-Nagerabi 1 , Abdulkadir E. Elshafie 2 , Suleiman S. AlKhanjari 1 , Saif N. Al-Bahry 2 & Mohamed R. Elamin 3 1 Department of Biological Sciences and Chemistry, College of Arts and Sciences, University of Nizwa, Oman 2 Department of Biology, College of Science, Sultan Qaboos University, Oman 3 Department of Chemistry, Sudan Academy of Science, Khartoum North, Sudan Correspondence: Saifeldin A. F. El-Nagerabi, Department of Biological Sciences and Chemistry, College of Arts and Science, University of Nizwa, Birkat Al Mouz, Nizwa, P. O. Box 33, PC 616, Oman. Tel: 968-9636-5051. E-mail: nagerabi@unizwa.edu.om; nagerabi@hotmail.com Received: April 9, 2013 Accepted: May 12, 2013 Online Published: May 16, 2013 doi:10.5539/jfr.v2n3p93 URL: http://dx.doi.org/10.5539/jfr.v2n3p93 Abstract Moulds and associated mycotoxins, especially aflatoxins, are important factors that advesely affect food and feed produced from contaminated plant and animal prodcuts. They are lethal to humans and animals, which emphasizes the great concern in food and feed production. In this study, the effects of baobab (Adansonia digitata) extracts on the vegetative growth and aflatoxin secretion by A. flavus (SQU21) and A. parasiticus (CBS921.7) strains were exzmined. Different concentrations of baobab fruit extract (1.5, 3, 5, and 7% w/v) and essential oil (0.5, 1, 3 and 5% v/v) was used. Fruit extract of baobab apparently inhibited the total aflatoxin secretion up to 20.4-68.5% for A. flavus and 11.9-69.1% for A. parasiticus, whereas the inhibition of aflatoxin B 1 production ranged between 29.9-79.2% and 13-68% for the two strains, respectively. The highest inhibition levels of total aflatoxin and aflatoxin B 1 secretion by A. flavus (47.2-95.7%; 28.1-89.7%) and A. parasiticus (42.7-93.3%; 25.9-80.2%) were obtained with essential oil extracted from baobab seeds. The two extracts significantly reduced the vegetative growth and the mycelial dry weights of selected fungi. This indicates the antifungal activity and inhibitory effect of baobab on the growth and aflatoxin production by the two toxigenic strains. Thus, fruit extract and essential oil of A. digitata can be suggested as potentially effective biocontrol and biopreservative substrates against food and feed contamination by aflatoxigenic moulds. Keywords: Adansonia digitata, Aspergillus flavus, A. parasiticus, baobab fruit, essential oil 1. Introduction Adansonia digitata L. (Baobab) of the family Malvaceae is a large iconic deciduous and stem-succulent tree indigenous to the dry regions of Africa. It is found in many countries of South Africa (Zimbabwe, Mozambique, South Africa), West Africa (Mali, Benin, Senegal, the Ivory Cost, Cameron, Burkino Faso), and East Africa Kenya, Uganda, Sudan, Tanzania) (Sidibé & Williama, 2002; Wickens & Lowe, 2008; Kamatou, VermaaK, & Viljoen, 2011; Vermaak, Kamatou, Komane-Mofokeng, Viljoen, & Beckett, 2011; De Smedt, Sanchez, Van den Bilcke, Simbo, Potters, & Samson, 2012). In the past decade, different parts of the baobab tree have been reported to be useful and this has attracted the interest of pharmaceutical companies and scientists. This is due to its various traditional uses as medicinal, nutritional and cosmetic plant (Igboeli, Addy, & Salami, 1997; Wickens & Lowe, 2008; Buchmann, Prechsler, Hartl, & Vogl, 2010; Kamatou et al., 2011). Recently, the European Commission authorized the importation of baobab fruit pulp as a novel food for human consumption (Buchamann et al., 2010). In 2009, it was approved by the Food and Drug Adminstration (FDA) as a food ingredient in the United States of America (Addy, 2009). The dry pulp is commonly used to prepare fruit juice with higher levels of vitamin C than orange, and calcium than milk (Assogbadjo, Chadare, Kakari, Fandohan, & Baidu-Forson, 2012). Various plant parts such as leaves, bark, and fruit pulp have been traditionally used as immuno-stimulant, anti-inflammatory, analgesic, and pesticide, and in the treatment of fever, diarrhoea, cough, dysentery, haemoptysis, tuberculosis, microbial infection and worms (Wickens & Lowe, 2008; Kamatou et al.,