Vol. 8(6), pp. 342-350, June 2014 DOI: 10.5897/AJFS2014.1161 Article Number: DD92FA346001 ISSN 1996-0794 African Journal of Food Science Copyright © 2014 Author(s) retain the copyright of this article http://www.academicjournals.org/AJFS Full Length Research Paper Nutritional composition of Detarium microcarpum fruit Florence Inje Oibiokpa1*, Godwin Ichekanu Adoga2, Abubakar Ndaman Saidu1 and Kudirat 1 Oluwatosin Shittu 1Department of Biochemistry, Federal University of Technology, Minna, Niger State, Nigeria. 2Department of Biochemistry, University of Jos, Jos, Plateau State, Nigeria. Received 26 March, 2014; Accepted 17 June, 2014 The pulp of Detarium microcarpum fruit was extracted and samples were analyzed for the proximate, vitamin, mineral and anti-nutrient composition using standard methods. Crude protein content obtained in D. microcarpum fruit was 4.68% while the crude fat content was 2.23%. The fruit also contained 4.47% moisture, 4.47% ash, 11.06% crude fibre and 65.38% total carbohydrates. The mineral composition of the fruit pulp showed that potassium was the most abundant (908.10 mg/100 g) and cadmium was the least abundant (0.03 mg/100 mg). Vitamin analysis showed that the fruit is rich in vitamin C (55.10 mg/100 g). The fruit was also discovered to contain 12.44 mg/100 g, vitamin E, 4.20 mg/100 g vitamin B2 and 0.17 mg/100 g folic acid. The anti-nutrient compositions of D. microcarpum were phytate (0.41 mg/100 g), cyanide (0.07 mg/100 g), tannin 0.17 mg/100 g, oxalate 1.06 mg/100 g, saponin (2.73 mg/100 g). D. microcarpum fruit is a good source of carbohydrates, fibre, minerals and vitamins and could also contribute to the daily requirements of protein and fats. The anti-nutrient contents of the fruit pulp are lower than established toxic levels. Key words: Detarium microcarpum, nutritional composition, proximate, antinutrient. INTRODUCTION In most developing countries, food shortage is becoming Abdullahi and Abdullahi, 2005) . evident as a result of population growth, competition for Many of such wild plants have been identified but lack fertile land and poverty. The diet of many rural and urban of data on their chemical composition has limited the dwellers is deficient in protein and high in carbohydrate, prospects of their utilization (Baumer, 1995). Many the implication is high incidence of malnutrition and reports on some lesser known seeds and fruits indicate increased dietary disease, a situation in which children that they could be good sources of nutrients for both man and lactating women are most vulnerable (Sadik, 1991). and livestock (Elemo et al., 2002). While every measure is being taken by various levels of Detarium microcarpum is a locally common plant often government to boost food production by conventional left when a farmland is cleared and left to fallow. It is a agriculture, a lot of interest is currently being focused on plant genus of the family Fabaceae (Legume family). D. the possibilities of exploiting the vast number of less microcarpum is widely distributed in semi-arid sub- familiar plant resource of the wild (Anwhange et al., 2004; Saharan Africa which include Benin, Burkina Faso, Corresponding author. E-mail: [email protected] Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License Oibiokpa et al. 343 Cameroon, Central African Republic, Ghana, Guinea, fruit was extracted by removing the thick bark of the fruit and Guinea Bissau, Niger, Nigeria, Senegal and Togo. scrapping the pulp off using a spatula. The pulp was blended into Detarium microcarpum fruit is edible and rich in vitamin fine powder using a blender. The pulp obtained from each fruit was weighed. C, the leaves and seeds are used for cooking, the roots, stem bark and stems are also used to treat ailments like meningitis, tuberculosis, itches and diarrhea (Eromosele Proximate composition determination et al., 1994). The seed coat of the fruit has also been For moisture determination, a moisture meter was used. 5 g of shown to possess antimicrobial activity due to the sample was weighed and placed on a moisture plate. The sample presence on steroidal saponins and flavonoids (Ebi and was placed on a moisture meter which operates at a temperature of Afieroho, 2011). The stem bark has been shown to 140°C and runs for 10 min. The moisture content was noted. contain heavy metals at concentration levels higher than The ash content was obtained using the dry ashing method. The weight of crucible was taken on a weighing balance and noted as tolerable limits (Ehianeta et al., 2013). Also, Wahedi and W1. 5 g of sample was weighed in a crucible of known weight using David (2013) reported that D. microcarpum fruit pulp, a weighing balance and weight noted as Wa. The sample was when included in the diet of rats had effect on haema- ashed in a muffle furnace at a temperature of 600°C for 6 h. The tological parameters and body weight of rats, they ash obtained was cooled in a desiccator. The weight of crucible + concluded that prolonged consumption of the fruit by ash was obtained using a weighing balance (W3) and % ash content was calculated. humans affect haematological parameters and body weight at excess medicinal doses. Ash (%) = Many food crops also contain natural chemical substances known to have effects on the nutritional status of food. Some of these natural occurring toxicants The crude protein content was determined using the Kjedahl method (1883). A Foss digestor 2006 model was used to digest the are antinutrients such as cyanogenic glycosides, phy- sample and a Kjeltic distiller (Foss) 2100 model was used to extract tates, oxalates lectin, saponins, alkaloids, chymotryp-sin ammonia. 1 g of sample was transferred into a digestion tube. 12 inhibitors, etc. Chronic exposure to these natural sub- ml of concentrated H2SO4, 7 g of potassium sulphate and 0.08 g of stances through intake of foods rich in them may lead to copper sulphate were weighed and transferred into the digestion the problem of toxicity (Conn, 1979; Nartey, 1980; tube. The mixture in the digestion tube was digested at 400°C.The digest was allowed to cool and 75 ml of water was added to dilute Rosling, 1987). the acid. 60 ml of alkaline solution was added to the sample in Tannins are polycyclic hydrocarbons found in high digestion tube (sodium thiosulphate, sodium hydroxide and water). amounts in tea leaves and spinach. They inhibit the The sample was then distilled in a Kjeltic distiller using 25 ml of 4% absorption of iron probably by forming water insoluble boric acid to trap ammonia which was titrated against HCl, till a pink iron-tannin complexes. colour was obtained. Oxalates inhibit the absorption of iron and calcium by Moles of HCl = Moles of NH3 = Moles of nitrogen in the sample. forming insoluble and calcium complexes. Thus, the presence of phytates, tannins and oxalates in plant foods A blank (sucrose) was used also to titrate substrate reagent make iron and calcium unavailable. Hydrogen cyanide nitrogen from sample. does not occur free but in combination with sugars to form nontoxic compounds known as cyanogenic glycol- Crude protein (%) = sides. Hydrogen cyanide is known to inhibit the respire- tory chain at cytochrome oxidase level. The lethal dose Where 14.01 is the atomic weight of nitrogen and 6.25 is the factor for hydrogen cyanide in man is 50-60 mg/kg body weight. used to convert percent nitrogen to crude protein. Saponins are steroids or triterpenoid glycosides which The crude fat content was determined using soxhlet extraction are characterized by their bitter astringent taste, foaming method. A 2050 soxtec auto extraction machine was used to extract properties and their effect on red blood cells (Osagie and the total lipid content. 3 g of sample was weighed in cellulose Effiong, 1998). thimbles and noted as w1. Empty cups were weighed and the The determination of nutritional value of food is weights noted as w2. 60 ml of hexane was added into the cups. Hexane was used to extract the oil from the sample. The thimbles fundamental to theoretical and applied investigations in and the cups were placed in the right positions in a soxhlet nutrition. This is often the basis of establishing the nutria- extraction unit. Complete extraction takes about 1 h and the tional value and overall acceptance of the food from the process includes heating at 20°C. The extracted oil in the cups consumer’s stand point (Wilson, 1979). were further dried in an oven for 30 min at a temperature of 105°C This study is aimed at determining the nutritional to ensure complete evaporation of hexane. Cups containing composition of the D. microcarpum fruit pulp, thus will extracted oils were then allowed to cool in a desiccator and weighed. The weight obtained was noted as w3. encourage the use of D. microcarpum as food. Fat (%) = × 100 MATERIALS AND METHODS Sample collection The crude fibre was analyzed using the method described by Onwuka, 2005. 2 g of defatted sample was weighed in a beaker The fruits of D. microcarpum were collected in March in Otukpo and noted as w1. 100 ml of a mixture of trichloroacetic acid, nitric Local Government area of Benue State, Nigeria. The pulp of the acid and 344 Afr. J. Food Sci. glacial acetic acid and water (20 g trichoroacetic acid, 50 ml nitric Concentration from graph × extract volume acid, 450 ml glacial acetic acid, and 500 ml water) mixture was Soluble Tannins (%) = placed on a reflux condenser and allowed to reflux for 1 h.