Application of laccase in aflatoxin B1 degradation: a review

The second component of the sustainable development goals, which is focused on zero hunger can only be actualized when safety issues that affect food security are tackled. In addressing food safety issues, the decontamination of aflatoxin b1 is a priority. Aflatoxin b1 is a class of mycotoxin that predominantly contaminates crops and their derivative processed foods. It has been reported to trigger the formation of cancer cells as well as pose a serious health challenge in humans that consume the contaminated food. The effective use of laccase enzyme (a ligninolytic enzyme) as an agent of bioremediation for wastewater and industrial effluent treatment initiated its use in aflatoxin degradation. This review highlights the potentials of laccase enzyme as a useful tool in aflatoxin b1 degradation. Also considered is the proposed mechanisms by which laccase enzyme catalyzes aflatoxin b1 degradation, and the factors affecting laccase activity such as temperature, ph, mediators and inhibitors. Studies have shown that due to the non-phenolic characteristic of aflatoxin b1, laccase-catalyzed aflatoxin degradation requires a long time, and was more effective in the presence of a mediator. Various reports observed different degradation time from 55 mins to 72 hours. Such degradation could be > 50 % after 48 hours of exposure to laccase. Furthermore, the use of laccase prevents the presence of chemical residue after treatment giving it advantage over the application of the existing chemical methods. This method provides a safer means of degrading aflatoxin b1 with minimal loss of the nutritional quality of treated food sample.