Aim. The focal theme of present investigation includes isolation of prodigiosin producing fish gut bacteria, enhancing its production using tannery solid waste fleshing, and evaluation of its pharmacological effect. Methods. Optimization of fermentation conditions to yield maximum prodigiosin, and instrumental analysis using FTIR, NMR, ESI-MS, TGA, and DSC. Results. The optimum conditions required for the maximum prodigiosin concentration were achieved at time 30 h, temperature 30°C, pH 8, and 3% substrate concentration. The secondary metabolite was analyzed using ESI-MS, FTIR, and NMR. Therapeutic efficacy was assessed by in vitro anticancer studies. Among the pathogenic bacteria Pseudomonas aeruginosa was most susceptible at the lowest concentration followed by Salmonella typhi. IC50 concentration was cell line specific (HeLa cells: 4.3 µM, HEp2: 5.2 µM, and KB cells: 4.8 µM) and remains nontoxic up to the concentration of 25 µM on normal Vero cells suggesting that cancerous cells are more susceptible to the prodigiosin at lower concentration. Conclusion. Maximum prodigiosin production was obtained with tannery fleshing. The potency of the fish gut bacterial secondary metabolite prodigiosin as a therapeutic agent was confirmed through in vitro antimicrobial and anticancer studies.

Three alkaline protease-producing strains designated as ANFLR1, NPLR1, and PROLR15 were isolated from Labeo rohita fish gut. These strains are able to produce alkaline protease using tannery fleshing (TF) as the sole carbon and nitrogen source and were identified as Bacillus megaterium, Serratia marcescens, and novel Pontibacter sps. Proteases from these organisms were purified to electrophoretic homogeneity following ammonium sulphate precipitation, ion exchange, and column chromatography. SDS-PAGE revealed molecular weights of the proteases to be 46 kDa (ANFLR1), 52 kDa (NPLR1), and 58 kDa (PROLR15). The optimum pH and temperature for the protease activity of ANFLR1, NPLR1, and PROLR15 were found to be 10. 5, 11.5, 9, and 70 • C, 60 • C, and 50 • C, respectively. The maximum protease activities at the optimum conditions were 420 U/mL (ANFLR1), 550 U/mL (NPLR1), and 530 U/mL (PROLR15). Inhibition of the NPLR1 protease by pepstatin confirmed aspartate-type enzymatic activity. Fe 3+ enhanced the activity of PROLR15 protease. Unlike all other microbial proteases known so far, the PROLR15 enzyme did not require Ca 2+ for activity and thermal stability. SDS-PAGE and scanning electron microscopy analyses confirmed the conversion of high molecular weight substrate (TF) to low molecular weight peptides by these proteases. The alkaline metalloprotease production by novel Pontibacter sps. and aspartate protease production by S. marcescens remain unexplored. Hence, TF with its relatively abundant availability can be beneficially utilized for alkaline protease production through the fish gut microbial fermentation processes.C. Sumathi et al. Eng. Life Sci. 2012, 12, No. 2, 223-237 proteases [3,9,[12][13][14][15]. The strains identified are featherdegrading Bacillus licheniformis [16-18], Bacillus subtilis [19], Bacillus cereus [20], Bacillus pseudofirmus [21] keratinolytic proteases that are useful in dehairing of animal hides, B. subtilis [22-24], Bacillus velesensis [25], B. cereus [26], B. licheniformis [27], and Bacillus pumilus [28], which subsequently yield the edible protein hydrolysates from fish, lean meat, Zein, fresh whey [12], and shrimp shell wastes [29,30] through fermentation processes [31][32][33]. Isolation of three different alkaline proteaseproducing bacterial strains ANFLR1, NPLR1, and PROLR15 after adaptation with TF is a novel approach which has not been explored yet. Alkaline proteases generally belong to the group of proteases, which have either a serine center or a metallo-type, exhibiting a wide pH range (pH 6-13). Similarly, Gram-negative bacilli Serratia sp. cultivated in proteinaceous substrates generally produce two different kinds of extracellular proteases-a major metalloprotease and a minor serine protease [10,34]. This is the first approach to reveal aspartate alkaline protease production by a Serratia strain. Furthermore, the present work explores the unexploited application of alkaline protease production by a novel Pontibacter strain PROLR15 isolated from the novel source Labeo roh...

The non-tanned proteinaceous tannery solid waste animal fleshing (ANFL), containing high nutritive value, was hydrolyzed using bacteria Selenomonas ruminantium HM000123 through submerged (SmF) and solid-state (SSF) fermentation processes. In addition, the effects of ANFL fermentative hydrolysate on growth, yield and biochemical properties of tomato plants were investigated. The treatments included T1 (SmF-ANFL), T2 (SSF-ANFL), T3 (recommended dose of NPK fertilizers) and a control without any amendment. Hydrolysates of both SmF-ANFL and SSF-ANFL treatments increased the biomass and yield as evidenced by plant height, stem girth, number of leaves and fruit yield when compared with both NPK and control plants. In this 90-day study, significant (p ≤ 0.05) changes were observed in SSF-ANFL treated plants compared to the other treatments. Protein profile analyzed through SDS-PAGE indicates the expression of a high molecular weight protein (205 kDa) and other proteins in the leaves of the SSF-ANFL treated plants. Overall results revealed that SSF-ANFL can be successfully utilized as a fertilizer particularly for cultivating tomato plants.