The acid solubilised collagen (ASC) and pepsin solubilised collagen (PSC) were extracted from the by-products (skin) of a cartilaginous fish (
). The ASC and PSC yields were 23.07% and 35.27% dry ...weight, respectively and were identified as collagen Type I with the presence of α, β and γ chains. As revealed by the Fourier Transform Infrared (FTIR) spectra analysis, pepsin did not alter the PSC triple helix structure. Based on the various type of collagen yield, only PSC was used in combination with chitosan to produce a composite film. Such film had lower tensile strength but higher elongation at break when compared to chitosan film; and lower water solubility and lightness when compared to collagen film. Equally, FTIR spectra analysis of film composite showed the occurrence of collagen-chitosan interaction resulting in a modification of the secondary structure of collagen. Collagen-chitosan-based biofilm showed a potential UV barrier properties and antioxidant activity, which might be used as green bioactive films to preserve nutraceutical products.
Fish play an important role in human nutrition. They are not only a great source of protein and healthy fats, but also a unique source of essential nutrients such as omega-3 fatty acids. Moreover, ...most fish are parasitized, and some of these parasites are able to influence the reallocation of resources in their favor and thus reduce the nutritional quality of the fish. The present study was conducted to investigate the impact of the third stage larvae (L3) of
Anisakis
spp. on the proximate composition, macro-minerals (potassium, calcium, and sodium), and fatty acids of European hake (
Merluccius merluccius
Linnaeus, 1758). In parasitized female group, our results revealed a decrease (
p
< 0.005) in the amount of carbohydrate by 6.5%, of calcium by 17%, and of 2 polyunsaturated fatty acids (arachidonic acid (C20: 4w-6), and eicosapentaenoic acid (C20: 5w-3) with 33% and 15% respectively. Simultaneously, an increase by 25% in the level of a single saturated fatty acid C10:0 was noticed. According to the principal component analysis, the parasitized female was wealthy of saturated fatty acids and monounsaturated fatty acids and contains less of polyunsaturated fatty acids, omega-3 fatty acids, and omega-6 fatty acids than the unparasitized female and male. No significant changes were observed in the biochemical composition of male hake, probably due to the low mean intensity of L3 larvae of
Anisakis
spp. in this group.
This study was designed with the aim to produce microbial proteases in presence of speckled shrimp by-product. For this reason, three strains belonging to Bacillus genus, namely, Aeribacillus ...pallidus VP3, Lysinibacillus fusiformis C250R, and Anoxybacillus kamchatkensis M1V were studied under co-culture procedure. A Taguchi L27 experimental design was applied to optimize the co-culture parameters. The experimental design was built with 9 factors (by-product powder concentration, the pH of the medium, the temperature, the sucrose concentration, the agitation speed, the inoculum sizes of VP3, M1V, and C250R strains, and the culture volume) at three different levels. The obtained results showed that a total protease activity of 8,182 U/mL could be achieved after 24 h of incubation in presence of 20 g/L shrimp by-product and 10 g/L sucrose, at an initial pH of 7, a 40°C temperature and absorbance, at 600 nm, of inoculum sizes of 0.1, 0.3, and 0.1 for VP3, M1V, and C250R strains, respectively. The agitation was set at 200 rpm, and the final volume was 25 mL. Taguchi’s design allowed the identification of temperature, the inoculum size for strain VP3, the inoculum size for strain M1V, and the final culture volume as the most influencing variables. A Box–Behnken design with 27 experiments was carried out for the optimization of these four selected factors. Following such design, the highest protease production reached was 11,300 U/mL. This yield was obtained in a final culture volume of 15 mL containing 20 g/L shrimp by-product powder and 10 g/L sucrose and inoculated with VP3, C250R, and M1V strains at 0.05, 0.1, and 0.2, respectively. The flasks were incubated at 45°C for 24 h with shaking at 200 rpm. The efficiency of chitin extraction by co-cultivation was investigated under the latter conditions. The chitin yield from shells by-product was 16.7%. Fourier-Transform Infrared (FTIR) analysis of the obtained chitin displayed characteristic profiles similar to that of the commercial α-chitin.
Glycosaminoglycans (GAGs), including hyaluronic acid (HA), dermatan sulfate (DS) and chondroitin sulfate (CS) are essential components of the bone and cartilage tissues. CS isolated from the ...cartilage tissue of various animals has found application in pharmaceuticals, cosmetics and food industries. In the first part of the present work, three methods were used and compared to extract and purify glycosaminoglycans (GAGs) from the cartilage powder of a local cartilaginous marine species «
». One of these GAGs, chondroitin sulfate (CS), will be exploited for the development of an anti-osteoarthritis generic at the request of a collaborative pharmaceutical industry. Thus this active ingredient must meet the requirements and tests described by the European Pharmacopoeia (Ph. Eur.). These tests are treated in the second part of this work.
Among the three methods that have been applied in the present work, in order to optimize the best process for GAGs preparation, enzymatic hydrolysis with papain followed by deproteinisation using trichloroacetic acid (TCA) was found the best one. The separation of the extracted GAGs using agarose gel electrophoresis, and the identification of bands by Fourier Transform Infrared (FT-IR) Spectroscopy, revealed that the cartilage GAGs of
are exclusively chondroitin sulfate (CS) and dermatane sulfate (DS), with proportions of 12.889 and 87.111% respectively, and that CS is of type C. The extraction technique with papain provides a product with GAGs content of around 90%. The TCA deproteinisation yielded the lowest level of protein (2.8%) in the extracted GAGs, less than 3%, which is the standard required by the European Pharmacopoeia (Ph. Eur.).Cetylpyridinium chloride (CPC) assay suggests that the titration technique, although is introduced by the Ph. Eur. for the determination of CS content, is not an accurate method, and that the values obtained by the optimized and validated HPLC method, described in this work, are more exact.
The extracted and purified active ingredient is perfectly conform to the tests described by the Ph. Eur. The results suggest that the co-product of
would be a perfect source of molecules of pharmacological interest, obtained by a simple and non-agressive process.
The present study developed a two-step strategy to enhance the production of extracellular polymeric substances (EPSs) by a thermotolerant chlorophyte,
Graesiella
sp., in view to their industrial ...valorisation. In the first step,
Graesiella
sp. was grown in outdoor conditions in pilot-scale photobioreactors of 100 L culture volumes. In the second step, the biomass collected in the exponential growth phase was submitted to heat stress (50 °C). A joint production of biomass reaching 0.50 g
dw
L
−1
day
−1
and of EPS production reaching 1.30 g
dw
L
−1
in 2 days was obtained. EPSs mainly contained polysaccharides (80%) and proteins (14%). FTIR and
1
HNMR revealed the presence of primary amine and sulfated groups. The EPSs contained antioxidant enzymes (SOD, CAT, and APX) maintained in an active state by the microenvironment offered by the EPSs. The EPSs were found to have a potent antioxidant activity via directly scavenging free radicals when compared to
l
-ascorbic acid.
Non-edible parts of crustaceans could be a rich source of valuable bioactive compounds such as the carotenoid astaxanthin and peptides, which have well-recognized beneficial effects. These compounds ...are widely used in nutraceuticals and pharmaceuticals, and their market is rapidly growing, suggesting the need to find alternative sources. The aim of this work was to set up a pilot-scale protocol for the reutilization of by-products of processed shrimp, in order to address the utilization of this valuable biomass for nutraceutical and pharmaceuticals application, through the extraction of astaxanthin-enriched oil and antioxidant-rich protein hydrolysates. Astaxanthin (AST) was obtained using "green extraction methods," such as using fish oil and different fatty acid ethyl esters as solvents and through supercritical fluid extraction (SFE), whereas bioactive peptides were obtained by protease hydrolysis. Both astaxanthin and bioactive peptides exhibited bioactive properties in vitro in cellular model systems, such as antioxidant and angiotensin I converting enzyme (ACE) inhibitory activities (IA). The results show higher astaxanthin yields in ethyl esters fatty acids (TFA) extraction and significant enrichment by short-path distillation (SPD) up to 114.80 ± 1.23 µg/mL. Peptide fractions of <3 kDa and 3-5 kDa exhibited greater antioxidant activity while the fraction 5-10 kDa exhibited a better ACE-IA. Lower-molecular-weight bioactive peptides and astaxanthin extracted using supercritical fluids showed protective effects against oxidative damage in 142BR and in 3T3 cell lines. These results suggest that "green" extraction methods allow us to obtain high-quality bioactive compounds from large volumes of shrimp waste for nutraceutical and pharmaceutical applications.
Different light qualities, i.e. ultraviolet (280–400 nm), blue (400–450 nm), green (500–550 nm) and red (620–670 nm) were combined with the actinic yellow light (SOX) (590 nm) under saturation of ...photosynthetic activity conditions, in order to consider the specific effects of each waveband on the red macroalga
Gracilaria gracilis
physiology
.
In this context, the fluctuation of biomass production, photosynthetic activity estimated as in vivo chlorophyll
a
fluorescence, protein and pigment contents, polyphenol concentration, antioxidant activity and the content and composition of the mycosporine-like amino acids (MAAs)-UV-absorbing compounds were studied. After 3 days of culture, the supplemented light had not induced any variation in photosynthetic pattern compared to the control (only SOX light). However, after 2 weeks of culture, supplemented blue light stimulated the accumulation of phenolic compounds which reached a value of 2.92 ± 0.22 mg g
−1
DW, 68% higher than the control. Moreover, supplemented green light induced the accumulation of proteins and R-phycoerythrin (R-PE), i.e. 29 ± 4.32 mg g
−1
DW and 0.91 ± 0.34 mg g
−1
DW, respectively, being an increase of 56% and 78%, respectively, compared to the control. Red light boosted the growth rate, i.e. 7.24% ± 1.06 compared to the control which was 2.17% ± 0.2. Finally, UV radiation induced a marked increase of MAAs reaching 133.03 ± 41.54 mg g
−1
DW, 162% higher content than the one in the control. The use of supplemented light of specific wavelengths to a saturated light irradiance for photosynthesis as an effective approach to increase the content of bioactive compound for biotechnology application is concretely discussed.
The diversity of marine biomasses is a set of exploitable and renewable resources with application in several sectors. In this context, a co-culture based on three protease-producing bacterial ...isolates, namely
Aeribacillus pallidus
VP3,
Lysinibacillus fusiformis
C250R
,
and
Anoxybacillus kamchatkensis
M1V strains, was carried out in a medium based on the blue swimming crab
Portunus segnis
bio-waste. Proteases production was optimized using a central composite design (CCD). The highest level of proteases production obtained was 8,809 U/mL in a medium comprising 75 g/L of
Portunus segnis
by-product powder (P
spp
). The biological value of P
spp
and its obtained derivatives were evidenced via accredited protocols. The recovered protein hydrolysate (P
Hyd
) was found to be active towards radical scavenging power and against angiotensin I-converting enzyme (ACE). The blue crab chitin (BC) extraction efficiency was achieved with a yield of 32%. Afterwards, chitosan was prepared through chitin
N
-deacetylation with a yield of 52%, leading to an acetylation degree (AD) of 19% and solubility of 90%. In addition, chitosan is found to be active against the growth of all pathogenic bacteria tested.
Graphical abstract
This study deals with the antimicrobial potential assessment of Ulva rigida, in regard to collection period and sampling site. Besides, we assess the chemical composition of bioactive compounds. For ...this purpose, Ulva rigida was seasonally collected from two northern sites in Tunisia, Cap Zebib rocky shore (CZ) and Ghar El Melh lagoon (GEM). Crude organic extracts were prepared using dichloromethane and dichloromethane/methanol and tested against 19 indicator microorganisms using the disk diffusion method and microdilution technique to determine the minimum inhibitory concentration (MIC). Silica gel column and thin layer chromatography were used for purification of active compounds. Nuclear magnetic resonance (NMR) and gas chromatography were used for compounds identification. Samples of Ulva rigida collected from the two sites have uniform antimicrobial activity throughout the year. Algae collected from the lagoon showed the largest spectrum of activity and were used for subsequent analysis. Bioguided purification of extracts from Ulva rigida, collected at GEM, leads to 16 active fractions with antibacterial effect mainly against Staphylococcus aureus ATCC 25923 and Enterococcus faecalis ATCC 29212. These fractions were identified as fatty acids, mainly oleic (C18: 1 w9), linoleic (C18: 2 w6), palmitic (C16: 0), and stearic (C14: 0). MICs values ranged from 10 to 250 μg/ml.
Seven different methods of DNA extraction were performed and compared in order to have the better DNA recovery in terms of quality and quantity. A PCR assay was realised based on the Cytb ...mitochondrial gene to identify 53 commercial food products of wide range diversity (Scombridae Thunnus species) commercialised in the Tunisian market, and we checked whether these products were correctly labelled under European and national legislations. Phylogenetic analyses on Cytb mitochondrial gene were used to study the relationships among the considered species. Tuna species was easily differentiated and confirmed by direct sequencing. The results showed a high deficiency in labelling: 96% of canned tuna did not specify the species, although the name of the species had to be mentioned. Partial least squares regression (PLS) showed relatively high values (45%) in all analysed data, suggesting substantial difference between the extraction procedures and matrices with SDS/PCI method being the most convenient.
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