Variations in nutrient and phytochemical constituents in leaf, stem and root of Garcinia manni (Oliv.) domesticated in tropical soil of Akwa Ibom State were assessed. Plant materials (leaf, stem and root) were collected from three (3) sampling locations in the study area. Elemental nutrient, proximate and phytochemical contents in the leaf, stem and root of G. manni were determined using standard procedures. There were significant (P < 0.05) variations in contents of nutrient elements, proximates and phytochemicals in leaf, stem and root of the test plant. The contents of anti-nutrients (cyanide, phytate, oxalate and glycoside) were relatively lower in stem than those of the leaf and root of the test plant. This study suggests that the test plant parts could be used as valuable material for the production of pharmaceutical drugs.  In addition, the lower contents of anti-nutrients in the stem attest to its utilization as chewing stick.

The effect of different soil conditions on some physiological indices of Costus afer was studied in two locations (Otuoke and Opolo) in Bayelsa State, Nigeria. The soils physico-chemical properties as well as mineral elements and phytochemical contents in leaf samples were assessed using standard procedure. The descending order of mineral elements in location I were, P > Ca > Mg > K > C > H > AI >Na > N, while that of location 2 were, P > Ca > C > K >Al >H > Mg > Na > N. The contents of calcium, magnesium, sodium, potassium, nitrogen and phosphorus in leaves of C. afer in location I were significantly (P < 0.05) higher than those of location 2, while the iron, zinc and lead contents in leaves of the test plant in location 1 were relatively higher than that of location 2. There were also marked variations in phyto chemical contents in leaves of the test plant between the two locations. This study indicates that soil factors have a considerable influence on the mineral elements and phytochemical contents of Costus afer.