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Pakistan Journal of Nutrition 11 (7): 574-579, 2012ISSN 1680-5194© Asian Network for Scientific Information, 2012Corresponding Author: Fang Zhong, School of Food Science and Technology, Jiangnan University, 214122 Wuxi, Jiangsu Province,China574Quantification of Total Polyphenolic Content and AntimicrobialActivity of Cocoa (Theobroma cacao L.) Bean ShellsJohn Nsor-Atindana, Fang Zhong, Kebitsamang Joseph Mothibe,Mohamed Lamine Bangoura and Camel LagnikaState Key Laboratory of Food Science and Technology, School of Food Science and Technology,Jiangnan University, Lihu Road 1800 Wuxi, 214122, Jiangsu, ChinaAbstract: This study evaluated the total Phenolic Compound Content (PC) and biological activity of CocoaBean Shell (CBS). Proximate compositions of the dry matter (CBS) were investigated, while the antimicrobialactivity was of CBS phenolic extracts in 80% acetone, ethanol, methanol and water performed by paper diskdiffusion and micro broth dilution methods against 4 bacterial strains. The results showed that CBSconsisted of mainly dietary fiber (60%), followed by protein (16.93%), fat (6.87%), polyphenols (4.85%) andmoisture (3.73%). The extracts inhibition zones diameter against the tested strains ranged from 16.1 to 9.19(mm) and were all significantly higher (p<0.05) than the negative control. The minimum inhibitoryconcentration ranged from 0.78 TPmg/mL to 2.58 TPmg /mL. The relatively high levels of dietary fiber coupledwith associated phenolics implies that this by-product might be of interest to the food industry, consideringits potential application as a functional ingredient in confectionery, bakery or in the preparation of low-fat,high-fibre dietetic products.Key words: Cocoa shells, phenolic content, antimicrobial activity, proximateINTRODUCTIONBioactive compounds from plants’ sources such asphenolics have gained substantial interest in recentyears owing to their unique functions and nutritionalvalues including antioxidant, antimicrobial,antimutagenic and antitumor activities. Antioxidants arebioactive micro-components present in food, having theability to retard or impede lipid oxidation. Free radicalshave been implicated for aging as well as food andchemical deterioration. Substantial literatures have beenpublished demonstrating, that plant polyphenoliccompounds scavenge free radicals, thereby protectinghumans against oxidative damage and free radicalrelated diseases (Beecher, 1999; Cicerale et al., 2009;Okawa et al., 2001). Recently, the use of syntheticadditives as antioxidants in food has come under heavycriticisms due to their undesirable consequences onhuman health (Goli et al., 2005). In order to minimize oreliminate the use of these artificial antioxidants in food,essential oils or plant extracts as natural antioxidantshave been used as agents against the proliferation ofmicroorganisms or protect food from oxidation (Bubonja-Sonje et al., 2011).Cocoa beans and their related products have beenextensively investigated in relation to their antioxidantand health promoting activities (Abbe-Maleyki andIsmail, 2010; Othman et al., 2007). The raw cocoa beantotal polyphenols is reported to contain 60% of bothflavanol monomers (epicatechin and catechin) andprocyanidin oligomers (dimmer to decamer). Thesecompounds are implicated as potential candidates tocombat free radical (Adamson et al., 1999). However,most of these studies have concentrated on cocoapowder and its related products such as chocolate, withfar less attention on the cocoa processing by-productswhich could be a cheap source of antioxidants.Moreover, conflicting reports and observations exist onthe influence of the antimicrobial activities of cocoapolyphenols (Percival et al., 2006) probably due toinsufficient studies involving cocoa phenolics in thearea. Meanwhile, accumulating evidence in relation toability the ability of polyphenolics from other plants’sources to inhibit microbial growth has been reported(Njume et al., 2011; Oonsivilai et al., 2008) Considering,its readily availability coupled with reports that CBS, asby-product, several tones of it are disposed as wasteevery year (Redgwell et al., 2003), it stimulate thethinking CBS could be a cheap source of polyphenoliccompounds for food fortification. The extraction andquantification of these phenolic compounds are therenecessary to allow assessment and eventual valueadded utilization of these cocoa processing wasteproducts.Few published reports are available regarding theantimicrobial power of cocoa and its’ related materialspolyphenolic extract, especially CBS. Consequently, thestudy was initiated to investigate the proximatecomposition of cocoa bean shells as well some