A total of 32 lactic acid bacteria (LAB) were isolated from 13 honey samples commercially marketed in Malaysia, 6 strains identified as Lactobacillus acidophilus by API CHL50. The isolates had antibacterial activities against multiple antibiotic resistant's Staphylococcus aureus (25 to 32 mm), Staphylococcus epidermis (14 to 22 mm) and Bacillus subtilis (12 to 19 mm) in the agar overlay method after 24 h incubation at 30 degrees C. The crude supernatant was heat stable at 90 degrees C and 121 degrees C for 1 h. Treatment with proteinase K and RNase II maintained the antimicrobial activity of all the supernatants except sample H006-A and H010-G. All the supernatants showed antimicrobial activities against target bacteria at pH 3 and pH 5 but not at pH 6 within 72 h incubation at 30 degrees C. S. aureus was not inhibited by sample H006-A isolated from Libyan honey and sample H008-D isolated from Malaysian honey at pH 5, compared to supernatants from other L. acidophilus isolates. The presence of different strains of L. acidophilus in honey obtained from different sources may contribute to the differences in the antimicrobial properties of honey.

The role of lactic acid bacteria (LAB) in honey as antifungal activity has received little attention and their mechanism of inhibitory of fungi is not fully understood. In this study, LAB were isolated from honey samples from Malaysia, Libya, Saudi Arabia, and Yemen. Twenty-five isolates were confirmed LAB by catalase test and Gram staining, and were screened for antifungal activity. Four LAB showed inhibitory activity against Candida spp. using the dual agar overlay method. And they were identified as Lactobacillus plantarum HS isolated from Al-Seder honey, Lactobacillus curvatus HH isolated from Al-Hanon honey, Pediococcus acidilactici HC isolated from Tualang honey and Pediococcus pentosaceus HM isolated from Al-Maray honey by the 16S rDNA sequence. The growth of Candida glabrata ATCC 2001 was strongly inhibited (> 15.0 mm) and (10 similar to 15 mm) by the isolates of L. curvatus HH and P. pentosaceus HM, respectively. The antifungal activity of the crude supernatant (cell free supernatant, CFS) was evaluated using well diffusion method. The CFS showed high antifungal activity against Candida spp. especially The CFS of L. curvatus HH was significantly (p < 0.05) inhibited growth of C. glabrata ATCC 2001, C. parapsilosis ATCC 2201, and C. tropicalis ATCC 750 with inhibitory zone 22.0, 15.6, and 14.7 mm, respectively. While CFS of P. pentosaceus HM was significantly (p < 0.05) effective against C. krusei, C. glabrata, and C. albicans with inhibition zone 17.2, 16.0, and 13.3 mm, respectively. The results indicated that LAB isolated from honey produced compounds which can be used to inhibit the growth of the pathogenic Candida species.

Aims: The objectives of this study were to evaluate the inhibitory activity of the cell-free supernatants (CFS) of lactic acid bacteria (LAB) isolates and determine the effect of pH, enzymes and heat treatment on the antifungal activity against Candida species. Methodology and results: A total of 25 strains of LAB were isolated from honey samples from Malaysia, Libya, Saudi Arabia, and Yemen. Four from twenty-five LAB isolates showed antifungal activity against Candida spp. and were identified as Lactobacillus plantarum (HS), L. curvatus (HH), Pediococcus acid lactic (HC), and P. pentosaceus (HM) using 16S rDNA sequence. The CFS of these isolates were evaluated for their antifungal activity using microtiter plate assay. The antifungal activity showed significant inhibitory activity against all Candida spp. especially growth of C. glabrata ATCC 2001 was significant (p < 0.001) completely inhibited by CFS of HH and HM at pH 3. Similarly, growth of C. glabrata ATCC2001 was significantly inhibited (p < 0.001) when treated with previously heated CFS of L. curvatus HH and P. pentosaceus HM at 90 degrees C and 121 degrees C. While, the growth of C. krusei ATCC 6258 was completely inhibited by CFS of L. curvatus HH at 121 degrees C. Treatment the CFS of LAB isolates with proteinase K and RNase II increased the antifungal activity against C. krusei and C. glabrata, whereas the activity of CFS produced by P. acidilactici was lost when treated with RNase II, especially against C. krusei. Conclusion, significance and impact of study: This study demonstrated that treated supernatant of LAB isolates with heating, adjusted pH and enzymes can be used to inhibit the growth of pathogenic Candida spp.

Maintaining a safe food supply has become an ever-changing endeavour as some emerging pathogens are discovered. Relying on traditional methods of thermal processing to create microbiologically safe foods is not sufficient. Research on finding other methods of controlling the growth and multiplication of pathogenic and spoilage bacteria needs to be explored. The use of crude bacteriocin produced by lactic acid bacteria may be one promising solution of controlling microbial growth in ready-to-eat (RTE) foods. The ability of lactic acid bacteria (LAB) to produce metabolites with broad-spectrum inhibitory activity that are heat stable is an important criterion for the application of LAB as preservative in food. 'Satar' was used as a model for this study because it is highly perishable and has a short shelf life (<12 h) at ambient temperature and, therefore, is unable to be stored for a long period of time. This chapter briefly describes the background of 'Satar' and its relations to microbiological safety. The study focused on choosing the suitable strains of LAB, identifying the isolates phenotypically using biochemical tests and VITEK 2 Compact System. The isolates were tested on their ability to inhibit LAB microflora, ability to inhibit a broad spectrum of Gram-negative and Gram-positive bacteria and ability to exhibit the antimicrobial activity after being subjected to heating temperatures. Among nine isolates of LAB from fermented fish, supernatants of four isolates were studied extensively for their heat stability at different heating temperatures (70, 80, 90, 100 and 121 degrees C) and heating times (5 and 20 min). Two strains, Lb. acidophilus and Lb. plantarum, were chosen for the incorporation of their crude bacteriocin in raw ' Satar', and their characteristics and microbiological shelf life were evaluated. Incorporation of crude bacteriocin of Lb. acidophilus and Lb. plantarum at 3 % and 6 % did not significantly affect (P>0.05) the water activity and pH, but significantly increased the moisture content when Satar was stored more than 20 h at ambient temperature. There was no significant difference (P>0.05) for a* value and b* value of 'Satar' among all samples at 0 h of storage time, except after 3 h of storage at ambient temperature. The colour analysis of samples showed a range of colour between grey and light grey. The incorporation of 3 % and 6 % crude bacteriocin of Lb. acidophilus and Lb. plantarum in raw ' Satar' could extend the shelf life from 8 h to 20 h and 17 h, respectively. This study has proven that LAB can be used to extend the shelf life of ready-to-eat food.

Keropok lekor is a popular Terengganu heritage traditional snack and its microbiological safety is one of the important aspects should be of concern. Thus, the present study was carried out to assess microbiological status of keropok lekor, and its production premises in Kuala Terengganu and Marang. A total of 136 samples were collected randomly from eight premises (in three replicates) comprising of raw materials, food contact surfaces and ready to eat (RTE). All samples were analysed for aerobic plate count (APC), total coliforms (TC) count, Escherichia coli and detection of foodborne pathogens. Results showed that the APC and TC count in raw materials (fish flesh, sago starch, ice, dough and chilli paste) ranged from below the detection limit (< 1.0 log(10) CFU/g) to 6.7 log(10) CFU/g and 4.6 log(10) CFU/g, respectively. While, food contact surfaces have the APC and TC in the range of < 1.0 to 6.4 log(10) CFU/cm(2) and < 1.0 to 4.1 log(10) CFU/cm(2), respectively. The food handlers hand swabs had APC and TC counts between 2.2 to 6.4 log(10) CFU/cm(2) and < 1.0 to 4.4 log(10) CFU/cm(2), respectively. RTE keropok lekor and dipping sauce contained APC in 1.8 to 5.5 log(10) CFU/g and < 1.0 to 5.1 log(10) CFU/g range, respectively. TC was detected as unsatisfactory level (> 1.7 lo g(10) CFU/g) in three keropok lekor samples. E. coli was found in 10.29% of samples and all of them were non-diarrheagenic serotypes. Two RTE keropok lekor and display containers were contaminated with E. coli. Coagulase positive staphylococci, Salmonella and Vibrio parahaemolyticus were detected in four, two and one samples, respectively, with none of them found to have Vibrio cholerae and Listeria monocytogenes. High prevalence of indicator organisms in food contact surfaces and food handlers hand indicated that hygiene practices were not well implemented. The unsatisfactory levels of presence of APC, TC and E. coli in RTE keropok lekor also described cross contamination due to inadequate hygiene practices after cooking process.

The microbiological quality of thirty ready-to-eat (RTE) keropok lekor (a sausage shape Malaysian fish product) was evaluated in comparison to microbiological guidelines for ready to eat foods. The two E. coli isolates were subjected to DNA sequencing, identified and tested for their resistance towards fifteen different antibiotics. The survival and growth of the isolated E. coli strains inoculated in keropok lekor at atmospheric air and vacuum packaging were also evaluated. Results revealed that four samples (13.33%) contained Enterobacteriaceae counts that exceeded the recommended allowable counts of 4.0 log(10) CFU/g. Unsatisfactory level of coliforms (> 1.7 log(10) CFU/g) was also observed in ten of the samples; two of which contained E. coli (2.1 +/- 0.17 and 3.7 +/- 0.02 log(10) CFU/g), suggesting of poor hygiene and sanitation practices. While the 'Possible E10' E. coli strain was observably resistant towards Nalidixic acid (30 mu g) alone, B10 E. coli isolate was worryingly resistant towards Ampicillin (10 mu g), Ceftazidime (30 mu g), Ciprofloxacin (5 mu g), Ceftriaxone (30 mu g), Nalidixic acid (30 mu g) and Tetracycline (30 mu g). This study also revealed that the growth and survival of the 'Possible E10' and B10 E. coli strains were not significantly affected by vacuum packaging when stored at both 4 degrees C and 28 degrees C. Therefore, intervention programmes to alert and educate small-medium enterprisers (SMEs) of keropok lekor producers on food safety as well as potential health risks that can be associated due to inappropriate handling procedures of such product, merits consideration.