Keethar Rashid Majeed(1), Amal Khazem Ghadban(1) and Faleh Mehdi Saleh*(1)
(1). Food technology Department, Factual of Agriculture, Al Basra University, Al Basra, Iraq.
(*Corresponding author: Dr. Faleh Mehdi Saleh. E-Mail: husienforever1@gmail.com).
Received: 27/07/2017 Accepted: 18/08/2017
Abstract
This study was conducted in April 2015 to August 2016, to investigate the inhibition activity of Lactobacillus spp. in vitro against fungi and aflatoxin using local isolates i.e., L. casi (AKF 1), L. plantarum (AKF2), L. casi (AKF 3), L. plantarum (AKF 4) and L. Jonsonii (AKF 5). The results of the statistical analyses showed that AKF4 exhibited the highest inhibition activity (97, 62.33 and 97%) among all isolates using live bacteria, thermally killed bacteria, and its metabolic compounds, respectively. In contrasts, the inhibition activity of AKF3 were (59, 14.33 and 59%) using live bacteria, thermally killed bacteria, and its metabolic compounds, respectively. Furthermore, aflatoxin binding was studied in vitro using the isolates (AKF 1,2,3,4,5) in MRS media containing 200 ppb of aflatoxin B1. The results revealed that using live bacteria of AKF4 at concentration 1×108 cfu/ml for 48 h showed highest binding percentage 99.9 %, while thermally killed bacteria of AKF1,2,5 at concentration 500 ppb for 48 h gave the highest binding percentage 100 % at 37 °C and pH 6.5. In addition, AKF 4 had the highest binding percentage 100% for both 24 h and 48 h at the same conditions. Binding efficiency results of thermally killed bacteria was 100 %, while binding efficiency of live bacteria ranged between (99.87-100%) when the bacteria was washed with water, acetonitrile and phosphate buffer saline.
Keywords: Wheat, Lactobacillus, Aflatoxin Binding B1, Fungal growth inhibition.
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