Protein Hydrolysis as a Way to Valorise Squid-Processing Byproducts: Obtaining and Identification of ACE, DPP-IV and PEP Inhibitory Peptides

The industrial processing of Argentine shortfin squid to obtain rings generates a significant amount of protein-rich waste, including the skin, which is rich in collagen and attached myofibrillar proteins. This waste is generally discarded. In this study, skin was used as a source of proteins that were hydrolysed using Trypsin, Esperase® or Alcalase®, which released peptides with antioxidant potential and, in particular, antihypertensive (ACE inhibition), hypoglycemic (DPP-IV inhibition) and/or nootropic (PEP inhibition) potential. Among the three enzymes tested, Esperase® and Alcalase produced hydrolysates with potent ACE-, DPP-IV- and PEP-inhibiting properties. These hydrolysates underwent chromatography fractionation, and the composition of the most bioactive fractions was analysed using HPLC-MS-MS. The fractions with the highest bioactivity exhibited very low IC50 values (16 and 66 µg/mL for ACE inhibition, 97 µg/mL for DPP-IV inhibition and 55 µg/mL for PEP inhibition) and were mainly derived from the hydrolysate obtained using Esperase®. The presence of Leu at the C-terminal appeared to be crucial for the ACE inhibitory activity of these fractions. The DPP-IV inhibitory activity of peptides seemed to be determined by the presence of Pro or Ala in the second position from the N-terminus, and Gly and/or Pro in the last C-terminal positions. Similarly, the presence of Pro in the peptides present in the best PEP inhibitory fraction seemed to be important in the inhibitory effect. These results demonstrate that the skin of the Argentine shortfin squid is a valuable source of bioactive peptides, suitable for incorporation into human nutrition as nutraceuticals and food supplements.

Composition and Anticoagulant Potential of Chondroitin Sulfate and Dermatan Sulfate from Inedible Parts of Garfish (Belone belone)

Glycosaminoglycans (GAGs) play a crucial role due to their significant biomedical functions. Chondroitin sulfate (CS) and dermatan sulfate (DS), the main representative family of GAGs, were extracted and purified from garfish (Belone belone) by-products, i.e., skin (GSB), bones (GCB), and heads (GHB), and their composition and anticoagulant activity were investigated. CS/DS were purified by ion-exchange chromatography with yields of 8.1% for heads, 3.7% for skin, and 1.4% for bones. Cellulose acetate electrophoresis was also explored for analyzing the extracted CS/DS. Interestingly, GHB, GSB, and GCB possessed sulfate contents of 21 ± 2%, 20 ± 1%, and 20 ± 1.5%, respectively. Physico-chemical analysis showed that there were no significant differences (p > 0.05) between the variances for sulfate, uronic acid, and total sugars in the GAGs extracted from the different parts of fish. Disaccharide analysis by SAX-HPLC showed that the GSB and GCB were predominately composed of ΔDi-4S [ΔUA-GalNAc 6S] (74.78% and 69.22%, respectively) and ΔDi-2,4S [ΔUA2S-GalNAc 4S] (10.92% and 6.55%, respectively). However, the GHB consisted of 25.55% ΔDi-6S [ΔUA-GalNAc 6S] and 6.28% ΔDi-2,6S [ΔUA2S-GalNAc 4S]. Moreover, classical anticoagulation tests were also used to measure their anticoagulant properties in vitro, which included the activated partial thromboplastin time, prothrombin time, and thrombin time. The CS/DS isolated from garfish by-products exhibited potent anticoagulant effects. The purified CS/DS showed exceptional anticoagulant properties according to this research and can be considered as a new agent with anticoagulant properties.

Identification of ACE I-Inhibitory Peptides Released by the Hydrolysis of Tub Gurnard (Chelidonichthys lucerna) Skin Proteins and the Impact of Their In Silico Gastrointestinal Digestion

Tub gurnard is a highly abundant fishery species caught as a discard in the Mediterranean Sea. This work proposes its valorisation through the release of potential antihypertensive peptides and glycosaminoglycans (GAGs) through the controlled hydrolysis of tub gurnard skin proteins. Four proteases (Esperase, Alcalase, Trypsin and Pronase E) were used to obtain potent angiotensin converting enzyme I (ACE)-inhibitory hydrolysates. Peptides and GAGs were separated and evaluated for their antihypertensive potential by fluorometry. The peptide-rich fractions derived from the Esperase and Alcalase hydrolysates showed very low IC₅₀ values (47 and 68 μg/mL, respectively). Only the GAGs from the Trypsin and Esperase hydrolysates were relevant ACE inhibitors (63 and 52% at 1 mg/mL, respectively). The peptide composition of the most potent ACE-inhibitory fractions derived from the Esperase and Alcalase hydrolysates (IC₅₀ values of 33 and 29 μg/mL, respectively) was analysed by RP-LC-ESI-MS/MS. The analysis suggests that the ACE-inhibitory activity is related to the peptide hydrophobicity, as well as to the presence of specific residues at any of the last four C-terminal positions. The in silico gastrointestinal digestion of these fractions yielded small peptides with antihypertensive potential.

Isolation and identification of an arabinogalactan extracted from pistachio external hull: Assessment of immunostimulatory activity

This work studies the extraction and purification of a novel arabinogalactan from pistachio external hull. It was extracted with a simple method from pistachio hull which is considered as unexploited waste. Based on the results of sugar analysis by GC-FID, glycosidic linkage by GC-MS, NMR spectroscopy, and molecular weight by Size Exclusion Chromatography, pistachio hull water soluble polysaccharides (PHWSP) were identified as a type II arabinogalactan (AG), with characteristic terminally linked α-Araf, (α1 → 5)-Araf, (α1 → 3,5)-Araf, terminally linked β-Galp, (β1 → 6)-Galp, and (β1 → 3,6)-Galp. DEPT-135, HSQC, HMBC and COSY NMR data suggested the presence of (β1 → 3)-Galp mainly branched at O-6 with (β1 → 6)-Galp chains, α-Araf chains, and terminally linked α-Araf. These AG from pistachio external hulls showed in vitro stimulatory activity for B cells, suggesting their possible use as an immunological stimulant in nutraceutical and biomedical applications.

In vitro lipolysis and physicochemical characterization of unconventional star anise oil towards the development of new lipid-based drug delivery systems

Lipid-based drug delivery systems are widely used for enhancing the bioavailability of poorly water-soluble drugs. However, following oral intake, lipid excipients often undergo gastrointestinal lipolysis, which drastically affects drugs solubility and bioavailability. That's why developing new lipid excipients which are resistant to digestion would be of great interest. We studied here the potential role of the unconventional Chinese star anise whole seedpod oil (CSAO) as an alternative multifunctional lipid excipient. Pancreatic lipase-mediated digestion of the extracted crude oil emulsion was assessed in vitro. Pancreatic lipase, being a strict sn-1,3-regioselective lipase, showed a high (16-fold) olive oil to CSAO activity ratio, which could be attributed to fatty acids composition and triglycerides intramolecular structure. For the sake of comparison, the non-regioselective lipase Novozyme® 435 exhibited higher activity than pancreatic lipase on CSAO emulsion, perhaps due to its ability to release fatty acids from the internal sn-2 position of TAGs. Apart counteracting lipolysis, CSAO oil also showed additional biopharmaceutical benefits including moderate antioxidant and antihypertensive activities. Altogether, these findings highlight for the first time the potential use of star anise unconventional whole seedpod oil as a multifunctional lipid excipient for the development of new lipid formulations.

Hybrid levan–Ag/AgCl nanoparticles produced by UV-irradiation: properties, antibacterial efficiency and application in bioactive poly(vinyl alcohol) films

Hybrid Ag/AgCl nanoparticles with high antibacterial activity were synthesised using bacterial levan.

Chondroitin/dermatan sulfate purified from corb (Sciaena umbra) skin and bone: In vivo assessment of anticoagulant activity

The present work deals with the extraction and purification of chondroitin sulfate/dermatan sulfate from skin (CSG) and bone (CBG) of corb (Sciaena umbra). Electrophoresis of these polymers in barium acetate buffer on cellulose acetate revealed two fractions similar to dermatan sulfate and chondroitin sulfate. The in vivo anticoagulant activity of both chondroitin sulfate/dermatan sulfate (CS/DS) were evaluated, at 25 and 75 mg kg^-1 of body weight (b.w), using activated partial thromboplastin time (aPTT), prothrombine time (TT) and thrombin time (PT) tests. Results showed that aPTT of CSG and CBG at 75 mg kg^-1 of b.w were prolonged by 1.59 and 1.48-fold respectively, compared with the control. Further, toxicity studies on liver performed by the catalytic activity of transaminases in plasma, oxidative stress markers and hepatic morphological changes demonstrated that CSG and CBG at both doses are not toxics. In summary, the higher activity and lower toxicity of both CS/DS, especially at 25 mg kg^-1 of b.w, recommended these compounds as a better drug candidate.

Oil from hake (Merluccius merluccius): Characterization, antioxidant activity, wound healing and anti-inflammatory effects

The aim of this work was to evaluate some biological properties of hake head oil (HHO) as well its lipid composition. The fatty acid profiles showed a dominance of unsaturated fatty acids overtaking 55% of the total fatty acids. Omega-3 polyunsaturated fatty acid profiles exhibited a dominance of EPA (eicosapentaenoic acid) (3.96%) and DHA (docosahexaenoic acid) (25.39%). The antioxidant activity was determined through two different assays: DPPH scavenging activity and β-carotene bleaching by linoleic acid assay. Eighteen mice were excised on their back and divided into 3 groups, treated with sterile saline, commercial healing cream and HHO, respectively. The wound closure rate, the hydroxyproline contents and the histopathology evolution in skin tissue were elaborated. Also, the anti-inflammatory activity was studied by carrageenan-induced mouse paw edema. Mice were divided into 3 groups treated respectively with sterile saline, anti inflammatory drug reference and HHO. The anti-inflammatory evaluation of HHO in mice exhibited an important inhibition of carrageenan-induced hind paws edema, as confirmed by the histological analysis, the superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) level. HHO displayed a significant wound healing effect probably due to the anti-inflammatory and antioxidant activities of its EPA and DHA contents. The overall results proved that HHO might be favorable drugs who exert a great therapeutic potential wound healing and anti-inflammatory effects in animal model.

Purification, compositional analysis, and anticoagulant capacity of chondroitin sulfate/dermatan sulfate from bone of corb (Sciaena umbra)

Chondroitin sulfate/dermatan sulfate (CS/DS) were isolated and purified for the first time from the bone of corb (Sciaena umbra) (CBG) and their chemical composition and anticoagulant activity were assessed. Infrared spectrum and agarose-gel electrophoresis for extracted CS/DS were also investigated. The results showed that the purified CS/DS obtained at a yield of 10% contains about 31.28% sulfate and an average molecular mass of 23.35 kDa. Disaccharide analysis indicated that CBG was composed of monosulfated disaccharides in positions 6 and 4 of the N-acetylgalactosamine (8.6% and 40.0%, respectively) and disulfated disaccharides in different percentages. The charge density was 1.4 and the ratio of 4:6 sulfated residues was equal to 4.64. Chondroitinase AC showed that the purified CS/DS contained mainly 74% CS and 26% DS. Moreover, the new CS/DS extracted from bone of corb showed a strong anticoagulant effect through activated partial thrombosis time (aPTT), thrombin time (TT) and prothrombin time (PT). In fact, CBG prolonged significantly (p < 0.05), aPTT and PT about 2.62 and 1.26 fold, respectively, greater than that of the negative control at a concentration of 1000 μg/mL. However, TT assay of CBG was prolonged 3.53 fold compared with the control at 100 μg/mL. The purified CS/DS displayed a promising anticoagulant potential, which may be used as a novel and soothing drug.

Sulfated polysaccharide isolated from Globularia alypum L.: Structural characterization, in vivo and in vitro anticoagulant activity, and toxicological profile

A sulfated polysaccharide from Globularia alypum L. (GASP) was extracted with a yield of 14.2%. GASP is composed mostly of sulfate and total sugars (13.29% and 71.56%, respectively) with small amount of proteins and lipids. The chemical and structural characterization was studied by Infra-Red spectroscopic and gas chromatography-mass spectrometry (GC-MS). GASP composed of eight carbohydrates where galactose, glucose, and mannose are the major compounds (33.47%, 26.71% and 18.21%, respectively). The in vitro and in vivo anticoagulant activities in rats were tested using the standard coagulation assays activated partial thromboplastin time (aPTT), prothrombine time (TT) and thrombin time (PT) tests. Both doses of GASP (200 and 500 mg/kg b.w) displayed a significant in vitro (1.22 and 1.33-fold, 1.17 and 1.27-fold, and 1.21 and 1.26-fold, respectively) and in vivo (1.47 and 2.52-fold; 1.20 and 1.43-fold; 1.21 and 1.40-fold, respectively) compared with the control. Toxicity studies on liver performed by the catalytic activity of transaminases in plasma, oxidative stress markers and hepatic morphological changes indicated that GASP at both doses are not toxics. The important pharmacological and toxicological profile of GASP revealed that this compound may be used as a novel and effective drug.

dentification and molecular docking of novel ACE inhibitory peptides from protein hydrolysates of shrimp waste

The effect of enzymatic hydrolysis by Savinase on the interfacial properties and antihypertensive activity of shrimp waste proteins was evaluated. The physicochemical characterization, interfacial tension, and surface characteristics of shrimp waste protein hydrolysates (SWPH) using different enzyme/substrate (E/S) (SWPH₅ (SWPH using E/S = 5), SWPH₁₅ (SWPH using E/S = 15), and SWPH₄₀ (SWPH using E/S = 40)) were also studied. SWPH₅, SWPH₁₅, and SWPH₄₀ had an isoelectric pH around 2.07, 2.17, and 2.54 respectively. SWPH₅ exhibited the lowest interfacial tension (68.96 mN/m) followed by SWPH₁₅ (69.36 mN/m) and SWPH₄₀ (70.29 mN/m). The in vitro ACE inhibitory activity of shrimp waste protein hydrolysates showed that the most active hydrolysate was obtained using an enzyme/substrate of 15 U/mg (SWPH₁₅). SWPH₁₅ had a lower IC₅₀ value (2.17 mg/mL) than that of SWPH₅ and SWPH₄₀ (3.65 and 5.7 mg/mL, respectively). This hydrolysate was then purified and characterized. Fraction F1 separated by Sephadex G25 column which presents the best ACE inhibition activity was then separated by reversed-phase high performance liquid chromatography. Four ACE inhibitory peptides were identified and their molecular masses and amino acid sequences were determined using ESI-MS and ESI-MS/MS, respectively. The structures of the most potent peptides were SSSKAKKMP, HGEGGRSTHE, WLGHGGRPDHE, and WRMDIDGDIMISEQEAHQR. The structural modeling of anti-ACE peptides from shrimp waste through docking simulations results showed that these peptides bound to ACE with high affinity.

Isolation, Purification and Structural Characterestics of Chondroitin Sulfate from Smooth hound Cartilage: In vitro Anticoagulant and Antiproliferative Properties

Chondroitin sulfate was extracted from the cartilage of smooth hound (CSSH) and then purified by anion exchange chromatography. The structual characteristic of CSSH was evaluated by acetate cellulose electrophoresis, FTIR, ¹³C NMR and SAX-HPLC. Molecular weight of CSSH was average 68.78 KDa. Disaccharide analysis indicated that CSSH was predominately composed of monosulfated disaccharides in position 6 and 4 of the N-acetylgalactosamine (45.34% and 32.49%, respectively). CSSH was tested for in vitro anticoagulant activity using the three classical coagulation assays (activated partial thromboplastin time (aPTT), prothrombine time (TT) and thrombin time (PT) tests). The finding showed that CSSH prolonged significatively (p < 0.05), aPTT, TT and PT about 1.4, 3.44 and 1.21 fold, respectively, greater than that of the negative control at a concentration of 100 μg/ml. The CSSH caused a significant antiproliferative activity against HCT116 cell, which was 79% of cell proliferation inhibition at the concentration of 1000 μg/ml. Further, CSSH presented no toxicity against the normal cells and no hemolysis towards bovine erythrocytes for all concentrations tested. CSSH demonstrated hopeful antiproliferative and anticoagulant potential, which may be used as a novel and effective drug.

Physicochemical properties of water-soluble polysaccharides from black cumin seeds

In the present work, water-soluble polysaccharides were isolated from black cumin seeds. Polysaccharides were characterized by their carbohydrate composition, molecular weight, thermal stability and by FTIR, NMR spectroscopy and X-ray diffraction. The surface, the functional and the antioxidant properties of black cumin water-soluble polysaccharides (BCWSP) were also investigated. BCWSP consisted mainly of galacturonic acid (30.20%), glucuronic acid (17.66%) and neutral sugar (22.99%). BCWSP was composed of high peak molecular weight. The FTIR spectrum obtained for BCWSP showed two most important absorptions, at 1659 and 1085 cm^-1, which corresponded to COO^- of uronic acids and pyranose form, respectively. NMR spectroscopy data suggested that the BCWSP is probably a rhamnogalacturonan backbone with galactan and arabinan side chains. X-ray pattern revealed the semi-crystalline behavior of BCWSP. WHC and OHC of BCWSP were relatively high and varied with temperatures. The polysaccharide zeta potential was greatly affected by pH. Results indicated that the decrease of surface tension has influenced foaming and emulsifying capacities. The DPPH radical scavenging activity of the BCWSP was 63.25% at 1 mg/mL. The BCWSP displayed moderate reductive, β carotene bleaching and chelating abilities. Overall, our results suggested that BCWSP could be used as alternative additives in food and non-food products.

Purification and structural elucidation of chondroitin sulfate/dermatan sulfate from Atlantic bluefin tuna (Thunnus thynnus) skins and their anticoagulant and ACE inhibitory activities

Chondroitin sulfate/dermatan sulfate (CS/DS) was extracted from Atlantic bluefin tuna (Thunnus thynnus) skin (SGAT) and was purified and characterized. SGAT was characterized by acetate cellulose electrophoresis, FTIR spectroscopy, ¹³C NMR spectroscopy and SAX-HPLC. According to the results obtained for specific chondroitinases (ABC and AC) and the SAX-HPLC separation of generated unsaturated repeating disaccharides, the polymer was found to contain a disaccharide monosulfated in positions 6 and 4 of GalNAc and disulfated disaccharides in different percentages. These results were confirmed by ¹³C NMR experiments. The average molecular mass was 24.07 kDa, as determined by PAGE analysis. SGAT was evaluated for its in vitro anticoagulant activity via activated partial thromboplastin time, thrombin time and prothrombin time tests. The polymer showed strong inhibitory activity against angiotensin I-converting enzyme (IC₅₀ = 0.25 mg mL⁻¹). Overall, the results suggest that this newly extracted CS/DS can be useful for pharmacological applications.

Chondroitin sulfate/dermatan sulfate (CS/DS) was extracted from Atlantic bluefin tuna (Thunnus thynnus) skin (SGAT) and was purified and characterized.

Synthesis and antibacterial activity of new peptides from Alfalfa RuBisCO protein hydrolysates and mode of action via a membrane damage mechanism against Listeria innocua

In this work we evaluated the mode of action of six new synthesized peptides (Met-Asp-Asn; Glu-leu-Ala-Ala-Ala-Cys; Leu-Arg-Asp-Asp-Phe; Gly-Asn-Ala-Pro-Gly-Ala-Val-Ala; Ala-Leu-Arg-Met-Ser-Gly and Arg-Asp-Arg-Phe-Leu), previously identified, from the most active peptide fractions of RuBisCO peptic hydrolysate against Listeria innocua via a membrane damage mechanism. Antibacterial effect and the minimum inhibitory concentrations (MIC) of these peptides were evaluated against six strains and their hemolytic activities towards bovine erythrocytes were determined. Prediction of the secondary structure of peptides indicated that these new antibacterial peptides are characterized by a short peptide chains (3-8 amino acid) and a random coli structure. Moreover, it was observed that one key characteristic of antibacterial peptides is the presence of specific amino acids such as cysteine, glycine, arginine and aspartic acid. In addition the determination of the extracellular potassium concentration revealed that treatment with pure RuBisCO peptides could cause morphological changes of L. innocua and destruction of the cell integrity via irreversible membrane damage. The results could provide information for investigating the antibacterial model of antibacterial peptides derived from RuBisCO protein hydrolysates.

Design, synthesis of novel Triazolones and bis-Triazolones derivatives under ultrasound irradiation and evaluation as potent angiotensin converting enzyme (ACE) inhibitors

The condensation of several primary amines and diamines with various N¹-ethoxycarbonyles N¹-tosylhydrazonates (1a-b), triazolones (2) and bis-triazolone (3) resulted in ethanol under ultrasound irradiation. Compared with the conventional methods, the main advantages of the present procedure are milder conditions, shorter reaction time and higher yields. The newly synthesized compounds were evaluated for angiotensin I-converting enzyme (ACE) inhibition. The results were compared to Captopril as a reference drug. Compounds 3b, 2h, 3a, 2d, and 2f showed not only inhibition activity with IC₅₀ values of 0.162, 0.253, 0.253, 0.281 and 0.382 µM, respectively, but also minimal toxicity. The docking of chemical compounds in the ACE active site showed possible inhibitory effect of all compounds on the catalytic activity of the enzyme, which would satisfactorily explain the anti-hypertensive effect of these compounds.

β-Chitin and chitosan from squid gladius: Biological activities of chitosan and its application as clarifying agent for apple juice

Chitin is the second most abundant polysaccharide in biomass after cellulose and the term chitosan usually refers to a family of polymers obtained after chitin deacetylation. The aim of this work was the preparation and the characterization of chitin and chitosan from the gladius (pen) of the European squid (Loligo vulgaris). A high level of deproteinization (more than 80%) was recorded using Alcalase^® with an enzyme/protein ratio of 10U/mg. The demineralization of the gladius was completely achieved within 8h at room temperature in HCl. ¹³C NMR, FTIR, and XRD diffractograms of prepared chitin and chitosan were taken and then degree of deacetylation of chitosan was calculated using ¹³C CP/MAS-NMR Spectroscopic. Further, in vitro antioxidant capacity of chitosan was evaluated on 1,1-diphenyl-2-picrylhydrazyl method (IC₅₀=3.2mgmL^-1) and the β-carotene bleaching assay (IC₅₀=3.3mgmL^-1). Antimicrobial activity was also investigated and assays indicated that prepared chitosan exhibited marked inhibitory activity against all microbial strains tested. Additionally, chitosan was tested such as clarifying agent for apple juice and showed powerful clarification capability, without affecting nutritional value. Furthermore, the results suggested that prepared chitosan could be used as alternative additive in pharmaceutical preparations and food industry.

Hepatoprotective and nephroprotective effects of sardinelle (Sardinella aurita) protein hydrolysate against ethanol-induced oxidative stress in rats

Ethanol consumption-induced oxidative stress that is a major etiological factor has been proven to play important roles in organs' injury. In the present study, we investigated the protective effect of fish protein hydrolysate prepared from the heads and viscera of sardinelle (Sardinella aurita) (SPH) against the toxicity of ethanol on the liver and kidney of adult male rats. Animals were divided into four groups of six animals each: group C served as control, group Eth received 30 % ethanol solution at the dose of 3 g/kg body weight, group SPH received only 7.27 mg of SPH/kg body weight, and group Eth-SPH received ethanol and SPH simultaneously at the doses of 30 % and 7.27 mg/kg body weight, respectively. All groups were treated by gavage way for 15 days. Ethanol treatment decreased the defense enzymatic system including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), which increased after the co-administration of SPH. Malondialdehyde (MDA) and toxicity biomarker levels such as aspartate transaminase (AST) and alanine transaminase (ALT) and alcaline phosphatase (ALP) and gamma-glutamyl transaminase (GGT) activities were enhanced after chronic ethanol treatment and reduced by co-treatment with SPH. The histological examination of the liver and kidney confirmed biochemical changes in ethanol-treated rats and demonstrated the protective role of SPH.

Globularia alypum methanolic extract improves burn wound healing process and inflammation in rats and possesses antibacterial and antioxidant activities

Burns are known as one of the most common and destructive forms of injury with a vast spectrum of consequences. Despite the discovery of various antibacterial and antiseptic agents, burn wound healing still has remained a challenge to modern medicine. Plants have been considered as potential agents for prevention and treatment of disorders in recent years. Globularia alypum L. (GA) is widely used in folk medicine against skin diseases and abscesses, however there is no scientific evidence justifying its use. This study aimed to evaluate the wound healing and anti-inflammatory effect, the antibacterial and antioxidant activities, as well as the chemical compositions of GA methanolic extract (GAME). Chemical compounds of GAME were examined by GC-MS. Wound healing effect was assessed by second-degree burn wounds in rats, anti-inflammatory activity was studied by carrageenan-induced rat paw edema, antioxidant activity was estimated by the DPPH, reducing power and β-carotene tests and antimicrobial activity was tested against 6 bacteria. A total of 17 compounds were identified. GAME-treated rats showed an improvement in healing process and carrageenan-induced hind paws edema as assessed by histological and biochemical investigations, compared to the control. A significant antioxidant and antibacterial activities were also observed in GAME-treated rats. GAME revealed a burn wound healing activity probably due to the anti-inflammatory, antimicrobial and antioxidant activities of its phytochemical contents. Thus, this study confirms its traditional use, however further more precise studies are needed for future clinical application.

Antioxidant, antibacterial, anti-inflammatory and wound healing effects of Artemisia campestris aqueous extract in rat

This study investigated some biological properties of Artemisia campestris aqueous extract (ACAE) as well its global chemical compositions. Twenty four rats were excised on the posterior neck skin area and divided into 4 groups, treated respectively with: sterile saline, glycerol, CICAFLORA and ACAE. The wound closure rate, histopathology evolution and the superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) level in skin tissue were evaluated. Anti-inflammatory activity was studied by carrageenan-induced rat paw edema. Animals were divided into 3 groups pre-treated respectively with sterile saline, acetylsalicylic acid (AA) and ACAE. The antibacterial activity was tested against six bacteria and the antioxidant activity was estimated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing power and β-carotene activities. Our results demonstrated a significant improvement in wound healing progression and in oxidative stress damage in the wounds tissues of ACAE-treated rats, compared to control. ACAE-treated rats revealed also a significant inhibition of carrageenan-induced hind paws edema as confirmed by the histological analysis. In addition to the antioxidant activity, ACAE showed considerable antibacterial activities. ACAE exhibited important wound healing effect probably due to the anti-inflammatory, antibacterial and antioxidant activities of its phytochemical contents. Therefore, this study confirms its popular use and highlights its promise in the development of new drugs.

Valorisation of smooth hound (Mustelus mustelus) waste biomass through recovery of functional, antioxidative and antihypertensive bioactive peptides

Concerns over the environmental and waste disposal problems created by the large amounts of by-products generated from fish processing industries are increasing worldwide. The bioconversion of those marine waste by-products through the enzymatic hydrolysis of their protein content offers the possibility for the development of bioactive peptides for use in various biotechnological applications. The present study aimed to investigate and evaluate the biological and functional properties of smooth hound (Mustelus mustelus) protein hydrolysates (SHPHs) obtained by treatment with intestinal and gastric enzyme preparations from M. mustelus viscera and porcine pancreatin. The results revealed that the SHPHs exhibited different degrees of hydrolysis and antioxidant activity. The hydrolysate produced by the intestinal crude extract presented the highest rate of antioxidative activity, showing an IC50 value of 1.47 ± 0.07 mg/mL in 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assays. The alkaline protease extract from the intestine of M. mustelus produced hydrolysate with the highest angiotensin I-converting enzyme (ACE) inhibitory activity (82 ± 1.52% at 2 mg/mL). All the protein hydrolysates showed excellent solubility and interfacial properties that were governed by pH. The major amino acids detected in SHPHs were glutamic acid/glutamine, aspartic acid/asparagine, histidine and arginine, followed by methionine, phenylalanine, serine, valine and leucine. Overall, the results indicated that smooth hound by-products can be used to generate high value-added products, thus offering a valuable source of bioactive peptides for application in wide range of biotechnological and functional food applications.

Effect of xylan oligosaccharides generated from corncobs on food acceptability, growth performance, haematology and immunological parameters of Dicentrarchus labrax fingerlings

The objective of this study was to determine the effect of two levels of inclusion of xylan oligosaccharides (XOS) extracted from corncob on growth, feed utilization, immune status and disease resistance of Mediterranean sea bass (Dicentrarchus labrax) fingerlings. Specimens of 4.75 ± 0.69 g at initial density of 2.7 ± 0.13 kg/m(3) were fed during 12 weeks at 0 g kg(-1) diet, 5 g kg(-1) diet and 10 g kg(-1) diet, dietary XOS level of inclusion in a commercial sea bass diet. Feeding the fish at both XOS dietary inclusion levels significantly increased weight gain, protein efficiency ratio and feed conversion ratio. Feeding of supplemented diets to fish led to reducing mortalities after challenging with A. hydrophila. The haematological and immunological parameters were assayed in both pre-challenged and post-challenged groups. There was an increased trend in red blood corpuscles, white blood corpuscles, pack cell volume, haemoglobin (Hb %) and serum protein content in treated groups over the control as time elapsed with the feeding trials. The serum immunoglobulin level and lysozyme activity showed an increased trend in the fed groups. Histological features of the liver showed lower lipid vacuolization and regular-shaped morphology of hepatocytes around the sinusoidal spaces denoting a better utilization of dietary nutrients supported with the morphometric data. In conclusion, XOS added at a designated dose (5 g kg(-1) diet) in the diet improves growth and stimulates the immunity and makes D. labrax fingerlings more resistant to infection by A. hydrophila.

Structural, functional, and ACE inhibitory properties of water-soluble polysaccharides from chickpea flours

The present study aimed to characterize and investigate the functional and angiotensin-I converting enzyme (ACE) inhibition activities of chickpea water-soluble polysaccharides (CPWSP). Physico-chemical characteristics were determined by nuclear magnetic resonance spectroscopy (NMR), Fourier transform-infrared spectroscopy (FT-IR) analysis, and X-ray diffractometry (XRD). Functional properties (water holding capacity: WHC, water solubility index: WSI, swelling capacity: SC, oil holding capacity: OHC, foaming, and emulsion properties) and ACE activities were also investigated using well-established procedures. The FT-IR spectra obtained for the CPWSP revealed two significant peaks, at about 3500 and 500 cm(-1), which corresponded to the carbohydrate region and were characteristic of polysaccharides. All spectra showed the presence of a broad absorption between 1500 and 670 cm(-1), which could be attributed to CH, CO, and OH bands in the polysaccharides. CPWSP had an XRD pattern that was typical for a semi-crystalline polymer with a major crystalline reflection at 19.6 °C. They also displayed important techno-functional properties (SWC, WSI, WHC, and OHC) that can be modulated according to temperature. The CPWSP were also noted to display good anti-hypertensive activities. Overall, the results indicate that CPWSP have attractive chemical, biological, and functional properties that make them potential promising candidates for application as alternative additives in various food, cosmetic, and pharmaceutical preparations.

Ability of natural astaxanthin from shrimp by-products to attenuate liver oxidative stress in diabetic rats

BACKGROUND

Reactive oxygen species play a crucial role in the pathogenesis of diabetes and its complications. The present study was undertaken, in vivo, to examine the protective effect of astaxanthin extracted from the shell waste of deep-water pink shrimp (Parapenaeus longirostris) against oxidative stress of alloxanic adult male rats.

RESULTS

Alloxan treatment revealed a significant elevation in plasma glycemia and lipid parameters such as total lipid, total cholesterol and triglycerides compared to the control group (C). In addition, liver malonaldialdehyde levels (MDA), an index of lipid peroxidation, significantly increased compared to control group. The activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) and reduced glutathione (GSH) levels decreased significantly compared to control group. Moreover, diabetic rats presented a significant increase in the activities of aspartate transaminase (AST) alanine transaminase (ALT) and alkaline phosphatase (ALP) in plasma, indicating considerable hepatocellular injury. Astaxanthin treatment restores these parameters near to control values. Histological studies on the liver tissue of alloxan and astaxanthin treated rats confirmed the protective effects of astaxanthin.

CONCLUSIONS

The results revealed that astaxanthin may be helpful in preventing diabetic complications in adult rats by reversing hepatotoxicity. It can be one of the ingredients in a number of healthy products.

Recovery, viscoelastic and functional properties of Barbel skin gelatine: investigation of anti-DPP-IV and anti-prolyl endopeptidase activities of generated gelatine polypeptides

The characteristics and functional properties of gelatine from freshwater fish skin (Barbus callensis) were investigated. The gelatine extraction efficiency was improved by an acid-swelling process in the presence of barbel crude acid protease extract. Barbel skin gelatine (BSG) contained 92.15% protein, 0.31% lipid and 0.72% ash. The amino acid profile of BSG showed a high percentage of imino acids. The electrophoretic profile showed that BSG is mainly composed of α- and β-components. BSG showed an excellent solubility and possessed interfacial properties, which were governed by the protein concentration. Biological activities of the hydrolysates obtained after digestion of BSG with several commercial proteases were evaluated. The results suggested that these hydrolysates are a good source of natural inhibitors of dipeptidyl peptidase-IV and prolyl endopeptidase and could potentially be used as dietary ingredients in the management of type 2-diabetes and/or neuropathological disorders.

Evaluation of efficacy of natural astaxanthin and vitamin E in prevention of colistin-induced nephrotoxicity in the rat model

OBJECTIVE

We evaluated the effect of astaxanthin (ASX) and vitamin E (vit E) on colistin methanesulfonate (CMS) induced-nephrotoxicity in rats.

METHODS

Animals were treated with sterile saline, 300000 or 450 000 IU/kg/day of CMS, CMS + ASX (20 mg/kg), CMS + vit E (100 mg/kg), or CMS + 1 ml/kg olive oil (OO) for 7 days. The plasma/urine creatinine (Cr) level, urine γ-glutamyl-transferase (GGT) level, and renal tissue activities in malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and reductase (GSH), as well as renal histology were performed.

RESULTS

CMS induced a tubular damage, increased the GGT and MDA levels, and decreased the activities of SOD, CAT, GPx and GSH. Co-treatment with ASX or vit E restored all biochemical parameters cited above and improved the histopathological damage.

CONCLUSION

Nephrotoxicity induced by CMS might be due to oxidative damage. The improvement by ASX or vit E seems to be related to their antioxidant properties.