Microbial Conversion of Shrimp Heads to Proteases and Chitin as an Effective Dye Adsorbent

Abstract

As a green and effective technique in the production of a large number of valuable products, the microbial conversion of chitinous fishery wastes is receiving much attention. In this study, protease production using the Paenibacillus mucilaginosus TKU032 strain was conducted on culture media containing several common types of chitinous fishery by-products serving as the carbon and nitrogen (C/N) nutrition source. Among the chitinous wastes, 1.5% (w/v) shrimp head powder (SHP) was found to be the most appropriate nutritional source for protease production when a maximal enzyme activity of 3.14 ± 0.1 U/mL was observed on the 3rd day of the culture period. The molecular mass of P. mucilaginosus TKU032 protease was estimated to be nearly 32 kDa by the polyacrylamide gel electrophoresis method. The residual SHP obtained from the culture medium was also considered to be utilized for chitin extraction. The deproteinization rate of the fermentation was estimated to be 45%, and the chitin obtained from fermented SHP (fSHP) displayed a similar characteristic Fourier-transform infrared spectroscopy (FTIR) profile as that from SHP. In addition, SHP, fSHP, and chitins obtained from SHP and fSHP were investigated for their adsorptive capacity of nine types of dyes, and chitin obtained from fSHP displayed a good adsorption rate on Congo Red and Red No. 7, at 99% and 97%, respectively. In short, the results provide potential support for the utilization of SHP in the production of P. mucilaginosus TKU032 protease via the fermentation as well as the preparation of chitin from fSHP as an effective dye adsorbent.

Conversion of Wheat Bran to Xylanases and Dye Adsorbent by Streptomyces thermocarboxydus

“…FTIR spectra of unloaded and loaded dye samples were measured in the presence of KBr over the range of 4000–400 cm −1 on Nicolet iS5 FTIR spectrophotometer (Thermo, Waltham, MA, USA) [ 56 ].…”

Utilization of Seafood Processing By-Products for Production of Proteases by Paenibacillus sp. TKU052 and Their Application in Biopeptides’ Preparation

“…A high-performance liquid chromatography device with a KW-802 column was used for purification following the gel filtration method. Finally, the recovery yield of P1 and P2 Several reports have defined the concentration of SPBP as a significant parameter for enzyme production [9,10]. Thus, the protease productivity of Paenibacillus sp.…”

“…Proteases are a group of enzymes capable of degrading protein directly to fragments of lower molecular weight (MW). These enzymes are produced by various living organisms, including microbes, plants, and animals [ 9 , 10 ]. Because of its widespread application, protease is one of the largest classes of industrial enzymes [ 11 ].…”

“…Among the protease-producing sources, microbes may provide several benefits, such as easy scalability for fermentation, less space requirement, and faster growth [ 10 , 11 ]. Besides, various protease-producing microbes can express the enzyme in high amounts in the medium using by-products as the nutrition source, for example, shrimp heads [ 9 , 10 , 11 , 12 ], squid pens [ 13 , 14 ], crab and shrimp shells [ 15 ], and agro-industrial wastes [ 16 , 17 ]. Among the by-product sources, seafood processing by-products (SPBPs) are considered a good candidate for producing protease because of the presence of protein in a significant proportion [ 9 , 10 , 11 ].…”

“…Paenibacillus was originally included in the genus of Bacillus , and later officially reclassified in 1993 as an individual genus [ 30 ]. Several important beneficial products of this genus have been discovered, including extra-cellular enzymes [ 9 , 10 , 31 ], antimicrobial substances [ 25 , 32 ], exopolysaccharides [ 25 , 33 ], anti-diabetic compounds [ 26 , 27 ], and antioxidants [ 25 , 28 ]. Interestingly, the production of proteases by Paenibacillus strains and their applications are rarely reported.…”