Phenotypic Characteristics of Lactic Acid Bacteria Isolates in Poultry Based on Total Plate Count, Gram Reaction, and Hemolytic Activity.
Amara Brilliant Marcelline Alfariza1, Muhammad Halim Natsir2, Feri Eko Hermanto2, Yuli Frita Nuningtyas2*

Universitas Brawijaya

Abstract

This study aims to characterize Lactic Acid Bacteria (LAB) isolates isolated from poultry based on key phenotypic traits, including microbial abundance through Total Plate Count (TPC), basic identity using Gram Reaction, and safety potential through Hemolytic Test. Bacterial samples were isolated from groups of free-range chickens and broilers, and TPC calculations were performed to determine the poultry group with the highest microbial population. The results of the microbial abundance analysis between the two poultry groups were analyzed using an independent t-test to determine statistical differences. Isolates from the poultry group with the best TPC values were then continued for further testing. The Gram Reaction Test was performed to confirm that the isolates were Gram-positive bacteria, which is a characteristic of the LAB group. Initial safety assessment was carried out through the Hemolytic Test by planting the isolates on blood agar media. The test results showed that the LAB isolates that were successfully isolated were Gram-positive, in accordance with the characteristics of this bacterial group. The results of the Hemolytic Test showed that lactic acid bacteria were included in the gamma hemolytic category which is an important criterion in the selection of safe probiotic candidates for poultry.

Keywords: Lactic Acid Bacteria, Total Plate Count, Gram Reaction, Hemolytic Test

Topic: Animal Nutrition