Antibacterial agents produced by lactic acid bacteria isolated from threadfin salmon and grass shrimp

Lactic acid bacteria (LAB) are non-pathogenic bacteria that have an important role in human daily life. LAB produce antimicrobial agents, such as bacteriocins, diacetyl and hydrogen peroxide which help to extend the shelf life of food products. In this study, LAB were isolated from selected seafood; threadfin salmon and grass shrimp. Antibacterial activity of LAB extracts against Salmonella typhimurium, Listeria monocytogenes, Bacillus cereus and Escherichia coli were determined using the disc diffusion method. Three strains of LAB were selected for the characterization of antibacterial agents produced by LAB. The parameters such as pH, heat, incubation period and medium, were analyzed in this experiment. Changes in environmental parameters affected the activity of antibacterial agents. The antibacterial agents produced by LAB were generally heat stable and stable in a wide range of pH levels. However, the inhibition activity of LAB was destroyed with a heat treatment of 121°C, and the antibacterial effect was reduced at a pH of 12, which occurs in most strains. The medium containing NaCl enhanced the antibacterial activity of P1S1 and P3S3 strains against S. typhimurium, L. monocytogenes and E. coli. Moreover, the antibacterial agents exhibited the greatest inhibition activity at incubation times between 24 and 72 h. The antibacterial activity was reduced after an incubation time of 96 h. The characterization of antibacterial agents aids in the improvement of food products safety

Methods for precise molecular detection of probiotic microflora : using adjusted molecular biology protocols, primer sets and PCR assays.

Lactobacillus sp. is probiotic bacteria for which many detection methods were envisaged. However, culture-based methods failed to achieve specific detection of this bacterium due to its presence in mixed bacterial complex communities. The PCR assay was optimized to detect and quantify Lactobacillus sp. specifically in complex microbial community of mixed bacteria. Four DNA extraction methods, DNA integrity, primers specificity and optimized PCR procedure were all tested. It was shown that extracted genomic DNA using Wizard® Genomic DNA Purification Kit showed the highest yield, quality and performance in gel electrophoresis. Moreover, the specificity of the primer set, Lacto-16S-F /Lacto-16S-R, specific for Lactobacillus sp. was checked and found highly specific. In conclusion, the best DNA extraction protocol, working specific primer set and working PCR assay were achieved for achieving efficient, specific and reliable molecular-based, culture-independent, method of detection of lactobacillus sp. in PCR-suppressor highly protein-complex environment of mixed bacteria community

Step and Step-Nc as a Tool for Big Data in Cloud Manufacturing

The terms big data, cloud manufacturing, predictive and additive manufacturing, and Internet of Things (IoT) are being most commonly used in the manufacturing industry nowadays. These terms are related to the fourth industrial revolution that emphasizes automation and data exchange between manufacturing tools/elements. Communication occurs between machines, products and even technicians or operators through various technologies while creating records of each interaction resulting in rapid growth of amount of data to be stored. Data acquisition is not a major issue since a structure or framework can properly connect these data in improving manufacturing efficiency. However, lack of effort in collecting and storing manufacturing data in the whole product life cycle process has made integration to be almost difficult to achieve. In this study, the adoption of STEP-NC method/technique was demonstrated in suiting the current explosion of big data in the industrial and manufacturing sector. The proposed methodology was developed through a study of an entity file structure and hierarchical concept in STEP and STEP-NC in gathering manufacturing data in a unified database. The challenge would be in making sense of the data, revealing the patterns in it and using them for operational improvements. The outcome of this study will be useful to support strategic decision making in product manufacturing

Review on wildlife value orientation for ecotourism resource management

Wildlife value orientation (WVO) is important in the management of conflicts in ecotourism, particularly in human and wildlife concerns as human-wildlife conflict reported cases have increased in recent years. Therefore, this article systematically reviews literatures on WVO globally from the context of theoretical approach as well as the effect of modernization on values towards wildlife. The theoretical approach highlights the cognitive hierarchy model and the development of four theories that shapes the cultural thought towards wildlife relevant to ecotourism products. By understanding, through integrated empirical investigation, the values people hold towards wildlife, it enables the development of effective decision makings in handling the conflicts in the realm of ecotourism product or resource management

Prevalence, knowledge, perception and factors influencing smoking among primary school students in Melaka smoke-free city

In order to increase the proportion of successful attempts to quit smoking, it is important to understand the factors influencing smoking among individuals since their young age. Objectives were to estimate the prevalence of smoking and to determine the knowledge, perception, and factors influence smoking among primary school students in Melaka Tengah District. A cross-sectional study carried out in October 2015. Sample sizes of 269 students were selected using stratified random sampling technique. A self-administered questionnaire was used for data collection. Results of this study showed ever smokers represent 28.6% of the students. The earliest age of smoking initiation was seven-year-old. The mean knowledge on smoking were higher (19.5 ±5.6) among those who doesn’t smoke as compare to those who ever smoke (16.9 ±4.2). About perception, 74.0% of the primary school children know the danger of smoking. Among those who smoke, the majority of them (74.0%) did not feel regret, smoking makes them look matured (44.8%), smoking solved their problems (43.8%). In regards to the factors influencing smoking, peer pressure has the highest prevalence which is 89.6%, early exposure from family members who are smokers (71.9%). Findings from this study should be considered as a warning for an impending epidemic. Thus, the smoking prevention program should have a greater role in schools and should be started as early as in kindergarten. Governmental commitment and social support are vital in health education and awareness and especially in ensuring that smoking programs are being implemented and sustained

Detection and quantification of probiotic bacteria using optimized DNA extraction, traditional and real-time PCR methods in complex microbial communities

The aim of this study is to optimize molecular detection and quantification methods of probiotic bacteria in complex microbial communities that have long been difficult for traditional culture-based methods. Traditional and real-time PCR were optimized to detect and quantify Lactobacillus spp. and Bifidobacterium spp. in complex microbial community. Fish and shrimp sauce were used as a model for complex microbial community. Directly form samples, 4 DNA extraction methods, primers specificity, PCR, and real-time PCR procedures were optimized, tested in comparison with samples, enriched bacteria and related standard bacterial strains, E. coli, Bacteroides, Enterococcus and Salmonella. Results showed that extracted genomic DNA using Wizard® Genomic DNA Purification Kit showed the highest yield, quality and performance. Moreover, the specificity of the primer set specific for Lactobacillus spp. and Bifidobacterium spp. was checked and found highly specific. The sensitivity of real-time PCR was higher than the conventional PCR and its quantifying potential is very precise for the detection and quantification of Lactobacillus spp. but not Bifidobacterium spp. which was absent in the tested samples. In conclusion, PCR and real-time PCR assays could be used very efficiently in quantifying and detecting Lactobacillus spp. that are present in very PCR-suppressive and complex microbial environment