Liquefaction of porcine hoof shell to prepare peptone substitute by instant catapult steam explosion.

Instant catapult steam explosion (ICSE) was proposed as a method to liquefy porcine hoof shell (PHS) and prepare a peptone substitute for fermentation culture, achieving environmentally friendly animal by-product recycling. The liquefaction of PHS was conducted at various pressures (0.5-2.3 MPa) for 5-30 min. As evidenced by the scanning electron microscopy analysis, ICSE caused randomly cracks changing the morphological structure of the solid fraction, and ultimately led to protein migration from the solid to liquid phase. Moreover, the chromatographic analysis revealed that the main constituents of the liquid fraction were short peptides (<2 kDa, 84.72%) and amino acids (1.68 mg/mL) at the pressure of 2.3 MPa for 30 min. Subsequently, liquid fractions were prepared as a PHS peptone substitute for fermentation culture. Results suggested the PHS peptone substitute as the main nitrogen source in media was more suitable for the growth of fungus. Therefore, ICSE provides a possibility of large-scale environmentally sustainable management of animal by-products through liquefaction.

Production of Valuable Compounds and Bioactive Metabolites from By-Products of Fish Discards Using Chemical Processing, Enzymatic Hydrolysis, and Bacterial Fermentation.

The objective of this report was to investigate the isolation and recovery of different biocompounds and bioproducts from wastes (skins and heads) that were obtained from five species discarded by fishing fleets (megrim, hake, boarfish, grenadier, and Atlantic horse mackerel). Based on chemical treatments, enzymatic hydrolysis, and bacterial fermentation, we have isolated and produced gelatinous solutions, oils that are rich in omega-3, fish protein hydrolysates (FPHs) with antioxidant and antihypertensive activities, and peptones. FPHs showed degrees of hydrolysis higher than 13%, with soluble protein concentrations greater than 27 g/L and in vitro digestibilities superior to 90%. Additionally, amino acids compositions were always valuable and bioactivities were, in some cases, remarkable. Peptones that were obtained from FPHs of skin and the heads were demonstrated to be a viable alternative to expensive commercial ones indicated for the production of biomass, lactic acid, and pediocin SA-1 from Pediococcus acidilactici.

Lupin peptone as a replacement for animal-derived peptone in rich culture media for yeast.

Lupin peptone was shown to be a suitable replacement for traditional bacteriological peptone in the culture of Candida glabrata, Candida albicans and Saccharomyces cerevisiae. This new medium formulation allows yeast researchers to increase safety and to eliminate the use of animal products for the culture of yeast in rich medium.

Potential of chicken by-products as sources of useful biological resources.

By-products from different animal sources are currently being utilised for beneficial purposes. Chicken processing plants all over the world generate large amount of solid by-products in form of heads, legs, bones, viscera and feather. These wastes are often processed into livestock feed, fertilizers and pet foods or totally discarded. Inappropriate disposal of these wastes causes environmental pollution, diseases and loss of useful biological resources like protein, enzymes and lipids. Utilisation methods that make use of these biological components for producing value added products rather than the direct use of the actual waste material might be another viable option for dealing with these wastes. This line of thought has consequently led to researches on these wastes as sources of protein hydrolysates, enzymes and polyunsaturated fatty acids. Due to the multi-applications of protein hydrolysates in various branches of science and industry, and the large body of literature reporting the conversion of animal wastes to hydrolysates, a large section of this review was devoted to this subject. Thus, this review reports the known functional and bioactive properties of hydrolysates derived from chicken by-products as well their utilisation as source of peptone in microbiological media. Methods of producing these hydrolysates including their microbiological safety are discussed. Based on the few references available in the literature, the potential of some chicken by-product as sources of proteases and polyunsaturated fatty acids are pointed out along with some other future applications.

The non-nutritional performance characteristics of peptones made from rendered protein.

Economic considerations require the use of inexpensive feedstocks for the fermentative production of moderate-value products. Our previous work has shown that peptones capable of supporting the growth of various microorganisms can be produced from inexpensive animal proteins, including meat and bone meal, feather meal, and blood meal, through alkaline or enzymatic hydrolysis. In this work, we explore how these experimental peptones compare to commercial peptones in terms of performance characteristics other than chemical make-up; these characteristics can impact fermentation operating cost. It is shown that experimental peptone powders produced through enzymatic hydrolysis are highly hygroscopic and that their physical form is not stable to humid storage conditions; those produced through alkaline hydrolysis and commercial peptones are less hygroscopic. When used in growth medium, all peptones contribute haze to the solution; experiments show that the source of haze is different when using enzyme- versus alkali-hydrolyzed peptones. Alkali-hydrolyzed peptones and all peptones made from blood meal are stronger promoters of media foaming than the commercial peptones; some enzyme-hydrolyzed peptones support very little foam formation and are superior to the commercial peptones in this sense. Alkali-hydrolyzed peptones are roughly equivalent to commercial peptones in the coloration they contribute to media, while enzyme-hydrolyzed peptones contribute intense coloration to media. No peptone caused a significant change in the viscosity of media. The experimental peptones studied here may be acceptable low-cost substitutes for commercial peptones, but none is equivalent to the commercial products in all respects.

Proteases production by two Vibrio species on residuals marine media.

A comparative study was carried out on the growth and production of alkaline proteases by two Vibrio species using different marine peptones from fish viscera residues. The bacteria tested, Vibrio anguillarum and Vibrio splendidus, are producers of high levels of proteolytic enzymes which act as factors of virulence in fish cultures, causing high mortality rates. The kinetic assays and subsequent comparison with the parameters obtained from the adjustment to various mathematical models, highlighted the potential interest of the media formulated, for their possible production on an industrial scale, particularly the production of proteases by V. anguillarum growing in rainbow trout and squid peptones.

[Characterization of soy peptone for the culture of microorganisms]. / Caracterización de la peptona de soya para el cultivo de microorganismos.

A soy peptone obtained with enzyme papain as a hydrolyzing agent was characterized. The physicochemical evaluation of the nutritive base attained at pilot and industrial scale showed the following characteristics: loss due to desiccation, 1.93%; aminic nitrogen, 1.71%; total nitrogen, 8.63%; chlorides (as NaCl), 5.45%; and pH, 6.94. For the functional evaluation of the pilot and industrial batches (3), developed soy peptone and another one taken as a reference from the Biotécnica Internacional firm (México), was incorporated to a mixture of bases. There were no significant differences (p < 0.05) in the absorbance values at 640 nm obtained in the promotion of the growth between the developed product and that of reference for Staphylococcus aureus ATCC 25923. For Streptococcus pyogenes ATCC 19615, it was observed a mild superiority (significant difference for p < 0.05) starting from the 5th hour of incubation in favor of the industrial batches compared with the reference soy peptone. It was proved that the promotion of the growth in the soy triptone agar and broth media and in malt extract agar for the evaluated microorganisms was similar or higher (significant differences for p < 0.05) in those prepared with the experimental soy peptone, in comparison with the formulated with the reference base.

Bacteria enclosure between silica-coated membranes for the degradation of organic compounds in contaminated water.

A non-conventional technique is proposed for the enclosure of either pure bacterial cultures or entire biocoenoses, for a possible utilization in the treatment of contaminated water. Biological components have been enclosed between polyester membranes coated by silica films consisting of: (a) SiO2 and nitrocellulose, (b) SiO2, ZnS crystals and nitrocellulose, (c) SiO2, TiO2 crystals and nitrocellulose, (d) SiO2, ZnS and TiO2 crystals and nitrocellulose. Morphological, structural and mechanical features of membranes were investigated by means of optical and electron microscopy, mercury porosimetry and wear resistance tests. Degradation kinetics have been finally studied by dipping the entrapped biomass into aqueous solutions of three different model organic compounds (alpha-d-glucose, ethyl alcohol and peptone). Results are very promising: in fact, no metabolic inhibition mechanisms of microorganisms have been evidenced. The porosity of the system allows mass transfer through the membranes, hence bacteria can grow and degrade pollutants. Besides, by this system, cells are constrained, avoiding they to spread across the retainment scaffold.

Simultaneous separation and quantitation of the major bovine whey proteins including proteose peptone and caseinomacropeptide by reversed-phase high-performance liquid chromatography on polystyrene-divinylbenzene.

A precise, sensitive and reliable RP-HPLC method was developed to enable not only unequivocal determination of alpha-lactalbumin and beta-lactoglobulin in bovine whey samples, but also simultaneous measurement of proteose peptone, caseinomacropeptide, bovine serum albumin and immunoglobulin G. The optimised method on the Resource RPC column allowed separation of the proteins in 30 min and could be applied to the analysis of soluble proteins in a variety of commercial and laboratory whey products. Furthermore, some qualitative information on protein heterogeneity and quality could be derived from the RP-HPLC analyses with additional data available from on-line electrospray mass spectrometry. Within- and between-day repeatability over a wide range of concentrations was excellent (RSD< or =5%) for all proteins except immunoglobulin G and bovine serum albumin where RSD was 7-10%. Analysis of grouped data from whey protein concentrate and whey protein isolate samples gave a limit of detection of < or =0.3% powder mass and a limit of quantitation of < or =1.0% powder mass for all proteins except immunoglobulin G. Limits of detection and quantitation were 0.6% and 2.0%, respectively, for this protein. Quantitative data obtained by the RP-HPLC method compared very favourably with data obtained by alternative methods of whey protein analysis.

Aqueous two-phase systems: a novel approach for the separation of proteose peptones.

Poly(ethylene glycol) and dextran aqueous two-phase systemis (ATPS) were developed to facilitate the separation of components of the proteose peptone fraction of bovine milk, which are mostly large casein derived peptides or glycoproteins. These have proved difficult to purify using conventional chromatographic procedures. ATPS exploit differences in hydrophobicity, size and ionic properties of the proteose peptones with a view to developing methods for future large scale preparations of the individual components of this whey protein fraction.

[The possibility of using a bacteriological peptone from whole blood as the nutrient base for growing microorganisms]. / Izuchenie vozmozhnosti ispol'zovaniia bakteriologicheskogo peptona iz tsel'noi krovi kak pitatel'noi osnovy dlia vyrashchivaniia mikroorganizmov.

Study of some parameters of the process of hydrolysis in addition to other experiments has made it possible to develop a method for obtaining a nutrient base for the cultivation of microorganisms with the use of cattle whole blood as protein substrate and papain as a hydrolyzing agent. The product thus obtained is characterized by high levels of amino and total nitrogen (4% and 14% respectively). Biological studies with the use of this product in different culture media and observations on the growth and characteristics of many microbial strains have shown the possibility of its use for the diagnosis of infectious diseases, for the control of the quality of foodstuffs and water.