ORIGINAL PAPER Protein, Lipid, Aliphatic and Triterpenic Alcohol Content of Caper Seeds ‘‘Capparis spinosa’’ Nizar Tlili • Taissir El Guizani • Nizar Nasri • Abdelhamid Khaldi • Saida Triki Received: 19 April 2010 / Revised: 19 July 2010 / Accepted: 23 July 2010 / Published online: 13 August 2010 Ó AOCS 2010 Abstract Capparis spinosa has a large natural distribu- tion over the Mediterranean basin. It is used in traditional medicines, and it is one of the most commonly found aromatics in the Mediterranean kitchen. In this paper, the total storage protein and lipids of Tunisian Capparis spinosa seeds were investigated, and the quantities were ca. 27% and ca. 33%, respectively. In this study also the composition of the aliphatic and triterpenic alcohols of C. spinosa was characterized for the first time. Aliphatic alcohol contents were ca. 45 mg kg -1 of total extracted lipids. Three compounds were identified, hexadecanol, octadecanol and tetracosanol, of which octadecanol was the major compound (ca. 28 mg kg -1 ). Triterpenic alcohol content was 396.82 mg kg -1 . Citrostadienol was the major compound (ca. 170 mg kg -1 ). b-Amyrin, gramisterol, cycloartanol and 2,4 methylcycloartenol were also detected and identified. Keywords Caper (Capparis spinosa) Á Seeds Á Storage protein Á Oil Á Aliphatic alcohol Á Triterpenic alcohol Introduction Plant seeds are important sources of proteins and oils for nutritional, industrial and pharmaceutical applications. Proteins are a necessary component of the diet of humans and other mammals. Accordingly, consumption of proteins, as a general class of macronutrients, is not normally asso- ciated with adverse effects. Production of purified vegetable protein is gaining increasing commercial importance due to the consumer preferences for vegetable sources of food and cosmetic ingredients [1]. In addition, the safety of proteins introduced into crops via genetic modification using recombinant DNA techniques for humans or animals may not be known [2]. Moreover, protein-calorie malnutrition (PCM) is a major nutritional syndrome affecting more than 170 million preschool children and nursing mothers in developing Afro-Asian countries [3]. For these reasons, proteins from seeds of non-conventional plants should be explored. These types of plants, which are found in abun- dance, are not yet being utilized. Such seeds may have good quality proteins that can be used to meet the increasing demand for dietary proteins [4]. Seed oils have attracted much attention because of their biological properties and effects. Recently, research has increased to investigate new plant sources of oil, especially from underexploited seeds [5, 6]. It has been suggested that minor compounds of unsaponifiable matter of most vege- table oils protect against cardiovascular complications and could reduce the risk of heart attacks by 15–45% [7, 8]. There has been recent interest in long-chain aliphatic alcohols as dietary supplements or nutraceuticals in the treatment of various chronic diseases, including diabetes and hypercholesterolemia [9]. To our knowledge, very few studies have been carried out on caper seeds’ storage components. As a spontaneous perennial shrub plant, the caper has a large natural distri- bution in the Mediterranean sea basin. The most important economic species is Capparis spinosa. This species has increased in economic importance in the Mediterranean N. Tlili (&) Á T. El Guizani Á N. Nasri Á S. Triki Laboratoire de Biochimie, De ´partement de Biologie, Faculte ´ des Sciences de Tunis, Universite ´ Tunis El-Manar, 2092 Tunis, Tunisia e-mail: Nizar.Tlili@fst.rnu.tn N. Tlili Á A. Khaldi Unite ´ de Recherche Gestion et Valorisation des Ressources Forestie `res, INRGREF, BP 10, 2080 Ariana, Tunisia 123 J Am Oil Chem Soc (2011) 88:265–270 DOI 10.1007/s11746-010-1662-2