H: Health, Nutrition & Food Antihyperlipidemic Effect of Sesame (Sesamum indicum L.) Protein Isolate in Rats Fed a Normal and High Cholesterol Diet Arundhati Biswas, Pubali Dhar, and Santinath Ghosh Abstract: The dietary influence of sesame protein isolate (protein content 91.5%), produced from dehulled, defatted sesame meal, on blood and tissue lipid profile and lipid peroxidation has been assessed in normal and hypercholesterolemic rats. To evaluate their hypocholesterolemic and antioxidative activity in vivo, we fed 18% sesame protein isolate with or without 2% cholesterol in comparison with casein to rats for 28 d. We determined plasma total protein, total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triacylglycerol as well as susceptibility of plasma and erythrocyte membrane lipid to oxidation ex vivo. Liver tissue lipid, cholesterol, phospholipids, and lipid peroxidations were also determined. The total cholesterol, LDL-cholesterol and triacylglycerol levels were significantly reduced in the sesame protein isolate and isolate containing cholesterol group than the corresponding control casein groups. HDL-cholesterol level was also increased in sesame protein isolate (41%) and protein isolate containing cholesterol group (38%) than the corresponding control casein and casein containing cholesterol groups. There was 49% and 64% lowering of plasma lipid peroxidation as well as 36% and 56% lowering of lipoprotein oxidation susceptibility (LOS) in the 2 experimental groups (sesame protein isolate and isolate containing cholesterol group) than the corresponding control (casein and casein containing cholesterol) groups. There was significant lowering of erythrocyte membrane lipid peroxidation (68% and 63% lowering in sesame protein isolate and isolate containing cholesterol groups) and liver lipid peroxidation (61% and 76% lowering in the 2 experimental groups than the corresponding control casein groups). Therefore, our results indicate that sesame protein isolate decreases cholesterol concentration in plasma, increases HDL-cholesterol, and also decreases plasma and erythrocyte membrane lipid peroxidation with or without cholesterol fed diet in rats. Keywords: hypercholesterolemic, lipid peroxidation, lipid profile, protein isolate, sesame (Sesamum indicum L.) Practical Application: Sesame protein isolate (SPI) can be produced from dehulled, defatted sesame meal. SPI consumption can reduce cardiovascular disease by reducing LDL cholesterol, triacylglycerol, and by increasing HDL cholesterol. As sesame is an important oil seed crop in various parts of the world, SPI can be utilized in various food formulation for its beneficial effect. Introduction Sesame seeds, which are mainly grown for oil, are a promis- ing source of plant proteins for human and animal consumption. Sesame is grown extensively in tropical and subtropical regions of the world. Total amount of seed produced was about 2.8 million metric tons (MT) and that of oil about 1.9 MT in 2002 (Namiki 2007). India is the largest producer of sesame with approximately 27% of its production. China, Myanmar, Mexico, Nigeria, Sudan, Bangladesh, Somalia, and Uganda are other major sesame produc- ing countries (Deshpande and others 1996). Sesame seed contains MS 20100351 Submitted 3/31/2010, Accepted 7/28/2010. Authors Biswas and Ghosh are with Dept. of Chemical Technology, Univ. Colleges of Science and Tech- nology, Calcutta Univ., 92 A.P.C. Road, Kolkata 700009, India. Author Dhar is with Dept. of Home Science, Viharilal College Campus, 20 B, Judges Court Road, Kolkata 700027, Univ. of Calcutta, West Bengal, India. Direct inquiries to author Ghosh (E-mail: santinathghosh@yahoo.com.hk). about 20% protein and in the defatted meal it is about 50%. The defatted meal also contains some undesired components along with sesame seed protein such as fiber, soluble sugar, phytates, and oxalates that can be eliminated to a large extent by producing protein isolates (Inyang and Ekanem 1996; Bandyopadhyay and Ghosh 2002). Current nutritional research and product development is fo- cused on products helping to reduce or control diet-related chronic diseases such as atherosclerosis, cancer, or liver failure, as well as special products for weight control. Diet content of proteins (Bey- nen and others 1983) is important for atherosclerosis development and diet manipulations can retard or accelerate the progression of this pathology. Dietary protein has been shown to affect plasma cholesterol concentration and metabolism of polyunsaturated fatty acids in the liver. It also affects the lipid peroxidation and distri- bution of fatty acids among liver and different lipoprotein classes. Soy protein has been extensively studied and has been reported to be an effective weight reducer (Aoyama and others 2000) and has been found to have hypocholesterolemic effect compared with C  2010 Institute of Food Technologists R  H274 Journal of Food Science  Vol. 75, Nr. 9, 2010 doi: 10.1111/j.1750-3841.2010.01821.x Further reproduction without permission is prohibited