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Bacterial metabarcoding analysis by 16S rDNA of five occurrences of mineral waters in Serbia (Torda, Slankamen Banja, Lomnički Kiseljak, Velika Vrbnica and Obrenovačka Banja) indicated the presence of a high percentage of the Proteobacteria phylum, followed by the Bacteroidetes phylum. The families Rhodobacteraceae, Burkholderiaceae, Pseudomonadaceae, Methylophilaceae and Moraxellaceae were the most dominant in the bacterial flora of the selected occurrences, whereas the most represented genera were Acinetobacter, Pseudorhodobacter, Pseudomonas, Limnohabitans, Massilia, Limnobacter and Methylotenera. The presence of coliform bacteria was not detected. Alpha diversity analysis revealed that Slankamen Banja and Lomnički Kiseljak were the richest of the selected occurrences, while the mineral waters of Torda, Velika Vrbnica and Obrenovačka Banja were characterized by similar diversity of bacterial communities determined by beta diversity analysis. Physical-chemical analysis revealed the value of total dissolved solids above 1 g/L, as well as elevated concentrations of some metals and non-metals. The research concluded that specific bacteria contribute to the development of biocorrosion and biofouling processes of water intake facilities. In addition, some of these bacteria might be potential indicators of the organic sources of pollution and/or biotechnological natural remediators in the treatment of contaminated waters.

A 56‐day feeding try was conducted to evaluate the effects of processed garlic known as black garlic (BG) fed at different inclusion levels (0 (BG0, control), 5 (BG0.5), 10 (BG1), 20 (BG2), 40 (BG4), and 80 (BG8) g/kg feed) on the growth, whole body composition, immune and antioxidant enzyme activities, gut microbiota and resistance to Vibrio parahaemolyticus infections in Litopenaeus vannamei (initial weight = 0.60 ± 0.001 g). The results revealed a significant improvement (p <.05) in the final weight, weight gain rate, specific growth weight, condition factor, protein efficiency ratio, survival rate, hepatosomatic index, and feed conversion ratio in the BG‐treated‐groups compared to the untreated. Correspondingly, the whole body proximate composition, immune, and antioxidant enzyme activities significantly improved in the treated groups than the untreated. Dietary BG had shaped the gut microbiota by significantly increasing (p <.05) the abundance of Phylobacterium, Ruegeria, and Pseudoalteromonas genera and decreasing (p <.05) the abundance of Vibrio genus than the control. Disease test with V. parahaemolyticus revealed significantly high (p <.05) resistance in the BG‐teated‐groups than the untreated. The BG8, BG4, BG2, BG1, and BG0.5‐treated groups respectively showed 72.1%, 62.8%, 55.8%, 41.9%, and 25.6% relative percentage survival. Dietary BG inclusion at 8% or at 80 g/kg feed could help improve shrimp growth and health. [ABSTRACT FROM AUTHOR]