Mycotoxicological and Antimicrobial Efficiency of Curcuma longa.

Abstract

Turmeric (Curcuma longa) is a spice widely used worldwide. It has been used in the treatment and prevention of diseases since ancient times. During harvesting and storage, turmeric is exposed to contamination by different fungi that are responsible for mycotoxins production. Mycobiota and mycotoxins associated with turmeric spices samples were screened in this study. Aspergillus was the dominant genus, it recorded with an average total counts of 4.76 log colony-forming unit/g, and appeared in all 40 tested samples. Molecular identification with internal transcribed spacer sequence was used to identify the species. The common species were Aspergillus flavus (with 80% frequency of occurrence) and Aspergillus niger (100%). Twelve and 20 samples were contaminated with total aflatoxins (AFs) and ochratoxins A (OTA) with concentrations 1.8-2.8 and 3.3-4.6 Parts Per Billioni (PPB), respectively. The search for suitable alternative antimicrobial drug resistance has increased, and this led researchers to explore the use of plant extract in the treatment of infections in both humans and animals. The antimicrobial activity of turmeric with two samples (sample no. 13 positive AFs and OTA, sample no. 2 with no toxins) on selected Candida albicans, Escherichia coli, and Staphylococcus aureus was evaluated. Different types of turmeric extracts were prepared using three solvents namely water, methanol, and ethanol using the disc diffusion method. The two tested turmeric samples extracts showed inhibition activity against all tested microorganisms. The zones of inhibition exhibited by extract of turmeric in methanol solvent from sample no. 13 against test organisms more effective and ranged from 10.6 to 15.4 mm. This is due to the confusion between antimicrobial activity of extract and its positively to mycotoxins content.