Comparative Evaluation of Cyanide Degrading Potential of Some Microbial Fermenters on Manihot esculentum Crantz

Abstract

Comparative Evaluation of Cyanide Degrading Potential of Some Microbial Fermenters on Manihot esculentum Crantz Aim: The aim of this work is to determine the cyanide degrading potentials of microbial fermenters on Manihot esculentum Crantz. Study Design: Pure culture of Weissella confusa, Lactobacillus brevis1,Lactobacillus fermentum 1, Lactobacillus plantarum 1, Aspergillus niger, Fusarium sp and Trichoderma sp were used for the study.  Freshly harvested cassava tuber was peeled, washed and cut into pieces. 50g of the substrate (homogenized cassava) was put into separately labeled Erlenmeyer flask and was made up to 100ml with sterile distilled water. Four flasks labeled WC, LB, LF1, and LP1 were inoculated with bacterial isolates. While the flasks labeled AN, FS and TS were inoculated with Mould isolates. However, the control flask labeled CTRL was not inoculated with any organism. The flasks were covered with sterile cotton wool and allowed to ferment for 4days at room temperature in a shaker. Methodology: Hydrogen cyanide content of cassava was determined using standard methods. Data generated from the study was subjected to statistical analysis using ANOVA.   Results: On day 1, there was no reduction in cyanide content across cassava samples. On day 2, L. plantarum 1, A. niger, L. fermentum, L. brevis, caused a significant (P<0.05) reduction (2.01±0.21 mg HCN/100g wet weight), (2.40±0.20 mg HCN/100gw.w), (2.60±0.02 mg HCN/100g w.w) and (2.80±0.60 mg HCN/100g w.w) respectively in the cyanide content of cassava sample.On day 3, A.niger, L. Plantarum 1, W. Confusa, L. Brevis brought about a significant (P<0.05)  reduction in the cyanide content of cassava sample (0.80±0.00 mg HCN/100g w.w), (1.20±0.20 mg HCN/100g w.w), (1.20±0.40 mg HCN/100g w.w) and (1.80±0.40 mg HCN/100g w.w) respectively. On day 4, L. plantarum 1, L. fermentum, Fusarum sp, L. brevis, Trichoderma sp and W. confusa (0.10±0.10 mg HCN/100g mg HCN/100g w.w), (0.21±0.01 mg HCN/100g w.w), (0.30±0.10 mg HCN/100g w.w), (0.40±0.20 mg HCN/100g w.w), (0.60±0.00 mg HCN/100g w.w), (0.90 ±0.10 mg HCN/100g w.w) respectively brought about a significant(P<0.05)  reduction in cyanide content of cassava sample In Conclusion: In conclusion L. plantarum 1 has outstanding cyanide degrading potential compared to other microbial fermenters used in this study.