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In the mycological survey of fresh salads of different vegetables, the collected samples were tested for total counts of moulds with special attention paid to the presence of potentially toxigenic species. The survey also included the isolation and the identification of species, as well as the evaluation of mycotoxin biosynthesis ability of potential producers of ochratoxin A (OA) and sterigmatocystin (STC). Mould counts ranged from 10.0 to 4.7x102 cfu g-1. The most common moulds found in fresh salads were Cladosporium (42.89%), Penicillium (25.78%), Aspergillus (14.67%) and Alternaria (6.89%). C. cladosporioides (40.44%), followed by A. niger (10.22%), P. aurantiogriseum (7.55%), A. alternata (6.89%) and Fusarium spp. (3.11%) were the most dominating species. Other species were represented with 2.22% (Eurotium spp.), 1.56% (Botrytis spp.), 0.67% (Phoma spp.), 0.44% (Geotrichum spp., Mucor spp., Phialophora spp.) and 0.22% (Emericella spp., Paecilomyces spp., Trichoderma spp., Xeromyces spp.). Twenty-two of 41 identified mould species were potentially toxigenic, which accounted for 46.18% of the total isolated population. The most frequent were the potential producers of ochratoxin A (17.77%). Potential producers of moniliformin were isolated in 3.11% of samples, while producers of fumonisin and STC were found in 2.67% and 2.44% of samples, respectively. The tested isolates of OA producers did not demonstrate the ability to biosynthetise this mycotoxins, but two out of five isolates of A. versicolor were found to biosynthesise STC in doses of 109.2 ng mL-1 and 56.3 ng mL-1. The obtained results indicate that such products may threaten human health, considering that isolated species were potentially toxigenic, while isolates of A. versicolor also biosynthesised STS.

Purpose – The purpose of this paper is to evaluate the frequency and antimicrobial susceptibility pattern of pathogens present in ready-to-eat salads available at a local market. Design/methodology/approach – A 100 salad samples were collected aseptically. Each sample (25 g) was homogenized in 225 ml of sterile peptone water and was serially diluted up to 1×106. Dilutions were inoculated on nutrient agar by surface spread plate technique. Aerobic colony count (ACC) was estimated by counting the colonies. Bacterial isolates were cultured on blood and MacConkey agar and identified on the basis of their morphology, culture characteristics and confirmed by API 20E and 20NE. Antimicrobial susceptibility was determined as per CLSI 2014. Findings – ACC range was 1.1×103 cfu/g to 5.8×109 cfu/g. Among these the highest ACC was found in channa chat (4.9×104 to 5.8×109 cfu/g). A total of 127 microorganisms were identified; 73 were gram negative rods (GNRs) and 24 were gram positive cocci (GPC). Among GNRs; Klebsiella spp. (n=18) was the predominant whereas among GPC, Staphylococcus aureus (n=6) were the chief pathogen. Klebsiella spp. showed 100 percent resistance to ampicillin, 89-78 percent to amoxicillin/clavulanic acid and 33 percent to imipenem, however, Enterobacter spp. were resistant to ampicillin (100 percent) amoxicillin/clavulanic acid (77 percent) and imipenem (23 percent). Staphylococcus aureus showed resistance to co-amoxiclav (83 percent) and penicillin (75 percent). Practical implications – This study revealed that effective control measures must been implemented and respected by throughout the entire food chain and better surveillance studies should be performed at national level to reduce the spread of bacteria by fresh salads. Originality/value – This paper explore the high prevalence of multidrug-resistant pathogens in different salads and most of the salads were found to be unhygienic for consumption. [ABSTRACT FROM AUTHOR]