Use of Hydrolysates from Yellowfin Tuna (Thunnus albacares) Heads as a Complex Nitrogen Source for Lactic Acid Bacteria

Abstract

Two different peptones obtained by enzymatic hydrolysis of yellowfin tuna (Thunnus albacares) head waste have been shown to be effective in promoting the growth of lactic acid bacteria (Lactobacillus bulgaricus Persian Type Culture Collection (PTCC) 1332, Lactobacillus acidophilus PTCC 1643, Lactobacillus casei PTCC 1608, Lactobacillus delbrukii PTCC 1333, Lactobacillus plantarum PTCC 1058, Lactococcus lactis PTCC 1336, and Lactobacillus sakei PTCC 1712). Peptones obtained from the enzymatic hydrolysis with Alcalase or Protamex were used instead of the standard peptones used in commercial MRS media. Peptones produced by Alcalase and Protamex had a 34% and 19% degree of hydrolysis, respectively. The resultsshowed that the peptones from Alcalase and Protamex were better at promoting lactic acid bacteria (LAB) growth than the commercial MRS media (P<0.05). The choice of proteolytic enzyme used to produce the fish hydrolysate had a considerable impact on the performance of the resulting hydrolysate, both in terms of maximum growth rate and biomass production. Peptones produced using Alcalase, with a higher degree of hydrolysis, induced better growth and performed better overall as an LAB substrate than those using Protamex. Current study revealed that enzymatic-modified fish by-products can be used as low cast nitrogen source for bacterial growth.

Effect of Methods of Hydrolysis on the Composition of Prosopis Africana seed Hydrolysates

“…In the analysis of fermenting Prosopis africana seed, [4]observed high proteinase activity which was attributed, in part, to the high protein content of the seeds. Protein in Prosopis africana seeds constitutes about 60 % or more of the seed kernel's weight [11]. In the present study, papain hydrolysate recorded crude protein value of 39.69 % which was higher than the values estimated from percentage nitrogen calculated from micro-Kjedahl as documented in the above cited works.…”

Evaluation of Functional Properties in Protein Hydrolysates from Bluewing Searobin (Prionotus punctatus) Obtained with Different Microbial Enzymes

“…Proteases such as Alcalase and Flavourzyme have been reported to hydrolyze fish protein efficiently (Kristinsson and Rasco 2000;Normah et al 2005;Dumay et al 2006;Safari et al 2009;Martins et al 2009). …”

Isolation of nitrate-reducing bacteria from an offshore reservoir and the associated biosurfactant production

“…The following two tests at time intervals of 0, 12,24,36,48,60,84,128,156,180,204 and 228 h were sampled with the whole ask, respectively. In addition, to investigate the nitrate reduction effect of the isolate on biosurfactant production, initial NaNO 3 concentrations at 1, 2, 3, 4 and 5 g L À1 were used on the glycerol producing medium.…”