Phytochemical, Proximate and Metal Content Analysis of the Leaves of <i>Psidium guajava</i> Linn (Myrtaceae)

Abstract

Purpose: To investigate the phytochemicals and some other constituents of the powdered leaves of Psidium guajava Linn and to evaluate the tolerability profile of the leaves because of their profound medicinal and non-medicinal uses. Methods: The phytochemical analysis of Psidium guajava was carried out by using a standard procedure. Ash, fat, protein, carbohydrate and fibre contents were determined using proximate analysis while the metal contents were determined using Pearson’s method. Results: The phytochemical analysis revealed the presence of saponins, glycosides, terpenoids, anthraquinones, tannins, flavonoids and alkaloids, the proximate analysis showed a low ash value of 2.80%, protein content 2.80%, fibre 2.70% and fat 1.80% but a relatively high content of carbohydrate 88.90%. The metal content analysis revealed the presence of seven metals Calcium 1.34 mg/kg, Magnesium 0.64 mg/kg, Potassium 0.76 mg/kg, Sodium 0.05 mg/kg, Iron 16.18 mg/kg, at concentrations below the tolerable upper intake level except for Manganese 29.23 mg/kg and Zinc 56.49 mg/kg Conclusion: The powdered leaves of Psidium guajava contain more of organic components and levels of manganese and zinc is above the tolerable upper intake established by the overseeing body.

Keywords: Psidium guajava, Toxicity, Screening, Tolerability, Leaves