Proximate and Mineral Elements Composition of Three Forest Fruits Sold in Port Harcourt, Nigeria

Abstract

This study aimed to assess the nutritional and trace elements composition of selected forest fruits sold for human consumption in Port Harcourt. Fruit contamination by heavy metals is an issue of global concern. Nondegradable elements bioaccumulations in tissues and organs have deleterious effects in man. Three (3) Agroforestry fruits species; (Spondias cytherea L. (Anacardiaceae), Syzygium malaccense (L.) Merr. & L. M. Perry Myrtaceae and Cola pachycarpa K. Schum. Malvaceae) were purposefully selected and sourced from three strategically located markets namely; Oil mill, Choba and D/line fruit markets. The fruit species were procured and washed with distilled water and the edible parts extracted, chopped and sun dried properly. The nutritional composition was analyzed using 18th edition of the Association of Official Analytical Chemist while trace metals were analysed using PIXE Accelerator. Spondias cytherea yielded high percentage of crude Protein (8.373±0.1) and Fibre content (11.73±0.03), while Syzygium malaccense was rich in Fat (7.17±0.02) and Ash (4.17±0.04). Moisture content was highest in Cola parchycarpa (12.63±0.05). PIXE Accelerator analysis revealed that the fruits contain high concentration of trace metals; S. malaccense contained Mg (1170±237.0ppm), Si (60.02±68.95ppm), Al (14.89±7.71ppm), Fe (10. 60±4.11ppm), Rb (3.20±0.00ppm) and Ti (1.82±0.00ppm). C. parchycarpa had Zn (6.22±11.80ppm), Cr (1.60±0.75 ppm), Mn (0. 71±0.87ppm) and Cu (0.38±0.33ppm). Ni (0.16 ppm) was found only in S. cytherea fruit. The forest fruits are rich in nutrients vital for healthy growth but the level of heavy metals (Mg, Al. Cr, Fe and Zn) in each of the fruits were above WHO/FAO permissible limit, therefore excessive consumption on a daily/weekly routine should be avoided.

Keywords: Forest fruits, proximate, heavy metals, human health