Effect of Solid- State Fungal Fermentation on the Bioactive Substances in the Pod of Albizia lebbeck

Abstract

Fermentation has been variously and positively engaged in the development of edible food material from unconventional sources and their nutritional enhancement. Albizia lebbeck is an underutilized leguminous tree with pods that hold a potential as a sustainable alternative feed source for livestock. This research was aimed at “Improving the nutritional status of Albizia lebbeck pods through fungal solid-state fermentation. Mature, dried Albizia lebbeck pods were collected from the premises of Ministry of Agriculture Ilorin, Ilorin, Kwara State, Nigeria. Isolation of predominant fungus from naturally fermented Albizia lebbeck pod was done using standard method. Isolated fungus was characterized and identified with macroscopic and microscopic features. The fungal spore suspension was used in pure culture for the solid-state fermentation of the pulverized pod for five days under laboratory conditions. The effects of fermentation on the nutritional factors of the pod were determined on the proximate content, phytochemical content, mineral composition, antioxidant status and the amino acid profile using standard methods. The isolated fungus was identified as Aspergillus terreus. The nutritional status of the pod was enhanced in the proximate content, macro minerals. Phytochemical; Tannin content increased from 5.99 ± 0.24 to 9.74 ± 0.06. Protein increased from 6.11 ± 0.00 to 10.50± 0.00 %, Magnesium increased from 183.75 ± 1.15 to 196.57 ± 3.68 ppm, Calcium increased from 55.00 ± 0.08 to 139.85 ± 3.18 ppm, total antioxidant capacity increased from 32.56 ± 0.021 to 64.39 ± 0.21, Amino acid; Leucine increased from 1.84 ± 0.06 to 3.17 ± 0.09. Fermentation of Albizia lebbeck pods by Aspergillus terreus was found to have desirable impact on the nutritional status as well as the enhancement of other bioactive substances like the antioxidant and amino acid content, the fermented pod has the potential to be an alternative beneficial source of food or feed supplement.