ACTA FAC MED NAISS 2021;38(1): 64-76

Assessment of Nutritional Composition and Antifungal Potential of
Bacteriocinogenic Lactic Acid Bacteria
from “Kati” against Toxigenic Aspergillus flavus

Paul Oladimeji Gabriel¹, Clement Olusola Ogidi², Oladipo Oladiti Olaniyi¹,
Bamidele Juliet Akinyele¹

¹Department of Microbiology, The Federal University of Technology, PMB 704 Akure, Nigeria
²Biotechnology Unit, Biological Sciences, Kings University, PMB 555, Odeomu, Nigeria

 SUMMARY

               In this study, the nutrient contents of “Kati”, a fermented cereal-based food, was revealed and antifungal activity of bacteriocin producing lactic acid bacteria (LAB) from “Kati” was assessed against aflatoxigenic Aspergillus flavus (A. flavus). The protein content (9.29%) of “Kati” was higher than (p < 0.05) wet milled-fermented sorghum (6.17%). During fermentation of milled sorghum to ready-to-eat ‘Kati’, anti-nutrient contents was reduced (p < 0.05) from 1.22 to 0.72 mg/100 g, 3.13 to 1.13 mg/100 g and 7.31 to 3.02 mg/100 g for tannin, phenol and phytates, respectively. Molecular technique revealed the identity of isolated LAB as Lactobacillus pentosus BS MP-10, L. paracasei 4G330, L. brevis ABRIINW, L. casei KG-5, L. sakei strain RFI LAB03, L. fermentum JCM 8607, L. plantarum KLDS 1.0607, L. rhamnosus JCM 8602 and L. lactis XLL1734. Among the isolated LAB, L. plantarum, L. lactis and L. fermentum have significant (p < 0.05) zones of inhibition of 11.0 mm, 9.1 mm and 7.8 mm, respectively, against aflatoxigenic A. flavus. The pronounced antifungal potency of L. plantarum cell free supernatant could be attributed to the presence of 3-phenyllactic acid, benzeneacetic acid, plantaricin (bacteriocin) as revealed by gas chromatography/mass Spectrometry (GC-MS). LAB produced metabolites with antifungal property that contributed to shelf life, flavor and nutrient contents of fermented foods.

Key words: cereal, proximate, 3-phenyllactic acid, benzeneacetic acid, GC-MS, fermentation