Guava is a low evergreen tree or shrub 6 to 25 feet high, with wide-spreading branchesand square, downy twigs,
is a native of tropical America. It is a tropical and semitropical plant. The branches are crooked, bringing opposite leaves. The flowers are white, incurved petals, 2 or 3 in the leaf axils, they are fragrant, with four to six petals and yellow anthers. The fruit is small, 3 to 6 cm long, pear-shaped, reddish-yellow when ripe. Guava is well known for its high amount of vitamin C, 4-10 times higher than that of an orange. The fruit and the leaf contain bitter-tasting substances, such as tannin, and essential oils. The fruit also contains a large number of fibers. The essential oils found in guava leaves are α-pinene and Cineole. In research report, it was found the flavonoid compounds such as, quercetin, avicularin, and guaijaverin.