Regular consumption of adequate quantities of lipids rich in omega-3 fatty acids is claimed to provide a broad spectrum of health benefits, such as inhibiting inflammation, cardiovascular diseases, diabetes, arthritis, and ulcerative colitis. Lipids isolated from many marine sources are a rich source of long-chain polyunsaturated fatty acids (PUFAs) in the omega-3 form which are claimed to have particularly high biological activities. Functional food products designed to enhance human health and wellbeing are increasingly being fortified with these omega-3 PUFAs because of their potential nutritional and health benefits. However, food fortification with PUFAs is challenging because of their low water-solubility, their tendency to rapidly oxidize, and their variable bioavailability. These challenges can be addressed using advanced encapsulation technologies, which typically involve incorporating the omega-3 oils into well-designed colloidal particles fabricated from food-grade ingredients, such as liposomes, emulsion droplets, nanostructured lipid carriers, or microgels. These omega-3-enriched colloidal dispersions can be used in a fluid form or they can be converted into a powdered form using spray-drying, which facilitates their handling and storage, as well as prolonging their shelf life. In this review, we provide an overview of marine-based omega-3 fatty acid sources, discuss their health benefits, highlight the challenges involved with their utilization in functional foods, and present the different encapsulation technologies that can be used to improve their performance.

Narayanan et al. V. parahaemolyticus With Pathogenic Potential in Seafood The conventional methods used to identify the pathogenic V. parahaemolyticus would be good for clinical isolates, but a more elaborate method is recommended for the detection of tdh gene in environmental isolates. This is the first comprehensive study on pathogenic V. parahaemolyticus in Kerala, India and demonstrates for the first time, the isolation of potentially pathogenic V. parahaemolyticus, carrying tdh gene from seafood collected from retail markets in Kerala.

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Luminescent Vibrio harveyi is common in sea and estuarine waters. It produces several virulence factors and negatively affects larval penaeid shrimp in hatcheries, resulting in severe economic losses to shrimp aquaculture. Although V. harveyi is an important pathogen of shrimp, its pathogenicity mechanisms have yet to be completely elucidated. In the present study, isolates of V. harveyi were isolated and characterized from diseased Penaeus monodon postlarvae from hatcheries in Kerala, India, from September to December 2016. All 23 tested isolates were positive for lipase, phospholipase, caseinase, gelatinase and chitinase activity, and 3 of the isolates (MFB32, MFB71 and MFB68) showed potential for significant biofilm formation. Based on the presence of virulence genes, the isolates of V. harveyi were grouped into 6 genotypes, predominated by vhpA+ flaB+ ser+ vhh1- luxR+ vopD- vcrD+ vscN-. One isolate from each genotype was randomly selected for in vivo virulence experiments, and the LD50 ranged from 1.7 ± 0.5 × 103 to 4.1 ± 0.1 × 105 CFU ml-1. The expression of genes during the infection in postlarvae was high in 2 of the isolates (MFB12 and MFB32), consistent with the result of the challenge test. However, in MFB19, even though all genes tested were present, their expression level was very low and likely contributed to its lack of virulence. Because of the significant variation in gene expression, the presence of virulence genes alone cannot be used as a marker for pathogenicity of V. harveyi.

Antimicrobial resistance (AMR) burden in Escherichia coli along the 90 km stretch of Vembanad Lake, Kerala, India was assessed. Seventy-seven percent of water samples drawn from 35 different stations of the Lake harbored E. coli. Antibiotic susceptibility test performed on 116 E. coli isolates revealed 81% were resistant to ≥ one antibiotic with 39 AMR profiles, 30% multidrug resistant, 32% extended spectrum  lactamase (ESBL) producers as per CLSI.The probability of isolating cefotaxime resistant E. coli was the highest 0.7 (P ≤ 0.05) in the Lake. Genetically diverse ESBL types blaTEM-116,blaCTX-M -152, blaCTX-M -27,blaCTX-M -55, blaCTX-M-205, and blaSHV-27 were identified. Molecular typing (ERIC PCR, MLST and PBRT) confirmed the diversity among E. coli between and within the stations. ST11439 and Single and Double Loci Variants of ST443, ST4533 were identified in Multi locus sequence typing (MLST) analysis. Inc plasmids (B/O, F, W, I1, FIIA, HI1, P-1, K/B and N) identified in the Lake evidences the transmission potential. Low multiple antibiotic resistance index (average < 0.2) indicating lower risk to the human population albeit, an emerging concern of ESBL resistance in the Lake. The occurrence of genetically variant ESBL E. coli in Vembanad Lake signals health hazards and necessitates pragmatizing strategic control measures.

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Antimicrobial resistance (AMR) burden in Escherichia coli along the 90 km stretch of Vembanad Lake, Kerala, India was assessed. Seventy-seven percent of water samples drawn from 35 different stations of the Lake harbored E. coli. Antibiotic susceptibility test performed on 116 E. coli isolates revealed 81% were resistant to ≥ one antibiotic with 39 AMR profiles, 30% multidrug resistant, 32% extended spectrum b lactamase (ESBL) producers as per CLSI.The probability of isolating cefotaxime resistant E. coli was the highest 0.7 (P ≤ 0.05) in the Lake. Genetically diverse ESBL types blaTEM-116,blaCTX-M -152, blaCTX-M -27,blaCTX-M -55, blaCTX-M-205, and blaSHV-27 were identified. Molecular typing (ERIC PCR, MLST and PBRT) confirmed the diversity among E. coli between and within the stations. ST11439 and Single and Double Loci Variants of ST443, ST4533 were identified in Multi locus sequence typing (MLST) analysis. Inc plasmids (B/O, F, W, I1, FIIA, HI1, P-1a, K/B and N) identified in the Lake evidences the transmission potential. Low multiple antibiotic resistance index (average < 0.2) indicating lower risk to the human population albeit, an emerging concern of ESBL resistance in the Lake. The occurrence of genetically variant ESBL E. coli in Vembanad Lake signals health hazards and necessitates pragmatizing strategic control measures.

No abstract