Original Article COMPARISON OF AMINO ACIDS IN 8 DIFFERENT BOILED TROPICAL FRUITS RADHA PALANISWAMY * , DHANYASRI SELVARAJ, SANDHIYA RENGANATHAN Department of Biotechnology, Dr. NGP Arts and Science College, Coimbatore 641048 Email: palaniswamyradha@gmail.com Received: 16 Oct 2018, Revised and Accepted: 10 Dec 2018 ABSTRACT Objective: To determine the protein quality, especially the amino acid content of 8 tropical fruits both raw and boiled samples. Eight different tropical fruits were used in the study (Apricot, Jamun, Dragonfruit, Pomegranate, Mangustan, Litchi, Jackfruit, and Kiwi. Methods: Ninhydrin method was used for the estimation of the concentration of amino acids present in the above fruits. Raw and boiled fruits were used for the study. Results: Both raw and boiled forms which showed thats Jamun and Mangustan contained highest concentration amino acids whereas apricot shows the lowest concentration of amino acids except in Jamun which showed higher values in the raw fruit whereas in others the boiled samples showed higher values. Conclusion: It was evident that tropical fruits have a good balance of the essential amino acids (both raw and boiled fomr) which provide significant sources of protein in our diet. Keywords: amino acids, ninhydrin, apricot, jackfruit, Dragon fruit, Pomegranate, Mangustan, Litchi, Jamun, Kiwi © 2019 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open-access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) DOI: http://dx.doi.org/10.22159/ijcpr.2019v11i1.31995 INTRODUCTION The amino acid content of fruit and fruit-derived foods is studied intensely because of the contribution to nutritional value, aroma, taste and health-promoting effects. The fruit contains a wide range of nutritional and medicinal components, such as vitamins, minerals, amino acids, and polysaccharides [1]. It is believed to have valuable senescence-retarding and cancer-preventative effects [2]. Numerous functional foods and health care products for clinical applications have been developed from the fruit or its organic extracts. Recent studies show that some fruits contain a relatively high quantity of protein. This potential protein source has been indicated by the crude protein content of their edible portion [3]. Scarce work has been done to determine the protein quality, especially the amino acid content of several tropical fruits which paved way for the current study. Fruits used in this study includes the following Apricot, Jamun, Dragonfruit, Pomegranate, Mangustan, Litchi, Jackfruit, Kiwi. Apricot (Prunus armeniaca) of the family rosaceae is popular regulating blood pressure and cholesterol and abundance of vitamin A [4]. Jamun (Syzygium cumini L.) is a polyembryonic species (family Myrtaceae) rich in anthocyanins and exhibits good antioxidant characteristics [5]. Dragonfruit (Hylocereus polyrhizus) from Latin America (Cactaceae family) is rich in vitamin C, calcium and phosphorus, and known for its fiber content [6]. The pomegranate (Punica granatum) an ancient, mystical, and highly distinctive fruit (Punicaceae family) has the potential therapeutic properties of treatment and prevention of cancer, cardiovascular disease, diabetes, dental conditions, and protection from ultraviolet (UV) radiation [7]. Mangostan (Garcinia mangostana L.) (Hypericaceae was alternatively known as Clusiaceae and Guttiferae) is a tropical evergreen tree, originated in the Sunda Islands is known for for treatment of abdominal pain, diarrhea, dysentery, infected wound, chronic ulcer, anti-tumoral, anti-inflammatory and anti-allergic [8]. Litchi (Litchi chinensis) of the family sapindaceae is regarded as a primitive group and acts as a plant pathogen [9]. Jackfruit (Artocarpus heterophyllus Lam.) of Moraceae family, is rich in phytochemicals, nutrients and antioxidant activity [10]. Kiwi (Actinidia deliciosa) from the actinidiaceae family is traced back to ancient Chinese civilization is filled with vitamin C, K and omega 3 fatty acids [11]. This study aims to show the estimation and concentration of amino acids present in commercially available fruits which are mentioned above. MATERIALS AND METHODS Collection and preparation of the sample The fruit samples apricot, jackfruit, pomegranate, litchi, mangustan, jamun, kiwi, dragon fruit were collected from the local market and used for the study. Preparation Ten grams of fruits were washed thoromghly under tap water followed by distilled water and blotted on a blotting paper. Peel was removed, chopped and macerated using mortal and pestle with an equal volume of distilled water. Another sample was prepared by boiling the fruits under steam (10 g for 5 min). Estimation of amino acids by ninhydrin method Nihydrin, a powerful oxidizing agent, decarboxylates the alpha- amino acids and yields an intensely colored bluish purple product which is colorimetrically measured at 570 nm. Materials required Ninhydrin: 0.4 g of stannous chloride was dissolved in 250 ml of 0.2M citrate buffer (pH 5.0). This solution was then added to 10g of ninhydrin in 250 ml of 2-methoxyethanol. Diluents Solution: The diluent solution was prepared by mixing water and n-propanol. Citrate Buffer: 0.2M Citrate buffer solution at pH 5.0 was prepared. Leucin stock standard and working solution: 10 ml of the stock leucine solution was diluted to 100 ml with distilled water in a standard flask (1 ml of this solution contains 100µg leucine). Procedure Into a serious of test tubes, 0.2, 0.4, 0.6, 0.8 and 1 ml of the working standard solution was pipetted out. In another set of test tubes, 0.2 International Journal of Current Pharmaceutical Research ISSN- 0975-7066 Vol 11, Issue 1, 2019