Proximate Analyses and Amino Acid Composition of Selected Wild Indigenous Fruits of Southern Africa

Abstract

A literature survey revealed that several wild indigenous Southern African fruits had previously not been evaluated for their proximate and amino acid composition, as well as the total energy value (caloric value). Fourteen species including Carissa macrocarpa, Carpobrotus edulis, Dovyalis caffra, Halleria lucida, Manilkara mochisia, Pappea capensis, Phoenix reclinata, and Syzygium guineense were analyzed in this study. The nutritional values for several species such as C. edulis, H. lucida, P. reclinata, and M. mochisia are being reported here for the first time. The following fruits had the highest proximate values: C. macrocarpa (ash at 20.42 mg/100 g), S. guineense (fat at 7.75 mg/100 g), P. reclinata (fiber at 29.89 mg/100 g), and H. lucida (protein at 6.98 mg/100 g and carbohydrates at 36.98 mg/100 g). Essential amino acids such as histidine, isoleucine, lysine, methionine, phenylalanine, tryptophan, and valine were reported in all studied indigenous fruits. The high protein content in H. lucida was exhibited by the highest amino acid quantities for histidine. However, the fruits are a poor source of proteins since the content is lower than the recommended daily intake. The jacket-plum (Pappea capensis), on the other hand, meets and exceeds the required daily intake of lysine (0.0003 g/100 g or 13 mg/kg) recommended by the World Health Organization.

Nutritional Characterization of Strychnos madagascariensis Fruit Flour Produced by Mozambican Communities and Evaluation of Its Contribution to Nutrient Adequacy

“…Lys exhibits significant thermal instability even at low temperatures [19]; therefore, some losses may have occurred during the drying and roasting processes and its concentration may be higher in S. madagascariensis fresh fruits. Although in low amounts, nfuma presents all nine essential AA, which is in agreement with the findings of Sibiya et al [42], who found eight essential AA (Trp was not evaluated) in 14 indigenous fruits.…”

“…Lys and Met were significantly higher in protein from Chicualacuala flour (16.9 mg/g protein) and Chókwè (15.6 mg/g protein), respectively, and Trp was significantly lower in protein from Marracuene flour (10.3 mg/g protein). Studies on the AA composition of indigenous fruits is scarce in the literature [ 42 ], and no information is available for fruits or products of Strychnos spp. [ 9 ].…”

“…Arg, the main AA in nfuma , was also found as the main AA of Dovyalis longispina and is generally abundant in other indigenous fruits [ 42 ]. Glu and Asp, the second and third most abundant AA in nfuma , have been described in relatively high amounts in other indigenous fruits [ 42 ]. These three AA have been described as major amino acids in nut seeds [ 38 ].…”

“…Met and Trp were the least abundant AA in nfuma (up to 15.6 mg/g protein), which is a common finding for proteins of plant origin [ 19 ]. Met was also found to be the least abundant AA by Sibiya et al [ 42 ] in almost all indigenous fruits; however, different results were found for Lys, one of the least abundant AA in nfuma (up to 16.9 mg/g protein), but with relatively high or intermediate levels in some indigenous fruits [ 42 ]. Lys exhibits significant thermal instability even at low temperatures [ 19 ]; therefore, some losses may have occurred during the drying and roasting processes and its concentration may be higher in S. madagascariensis fresh fruits.…”

Wild Edible Plants: A Challenge for Future Diet and Health

“…From the perspective that wild food plants are increasingly considered a potential source of natural healthy products, it is fundamental to foster biochemical research aimed at documenting their nutritional properties and main bioactive products [8,9]. The phytochemical and nutritional profiles of the species in question can therefore constitute basic knowledge for food pairing with other ingredients to improve nutritional and/or sensory quality and to find innovative cooking methods, allowing key molecules responsible for functional properties to be enhanced.…”