Chemical composition of some wild peanut species (Arachis L.) seeds

Oil, protein, ash, and carbohydrate contents, iodine value, and fatty acid and sterol compositions were studied in seeds of Arachis trinitensis, A. ch iquitana, A. kempff-mercadoi, A. diogoi, R benensis, R appressipila, R vali da, A. kretschmeri, A. helodes, R kuhlmannii, A williamsii, R sylvestris, A . matiensis, R pintoi, R hoehnei, R villosa, and R stenosperma. Oil content was greatest in A. stenosperma (mean value 51.8%). The protein level was h igher in A. sylvestris (30.1%) and A. villosa (29.5%). Mean value of oleic acid varied between 30.6% (A. matiensis) and 46.8% (Arachis villosa), and l inoleic acid oscillated between 34.1% (A. villosa) and 47.4% (A, appressipi la). The better oleic-to-linoleic (O/L) ratio was exhibited by R villosa (1 .38). Some species showed higher concentration of behenic acid. The greates t level of this fatty acid was found in A. matiensis (6.2%). Iodine value w as lower in A valida (99.2). The sterol composition in the different peanut species showed higher concentration of beta-sitosterol (mean values oscill ated between 55.7 and 60.2%) followed by campesterol (12.4-16.5%), strigmas terol (9.7-13.3%), and Delta(5)-avenasterol (9.7-13.4%). The chemical quali ty and stability of oils (iodine value and O/L ratio) from wild peanut stud ied in this work are not better than those of cultivated peanut.