M. Carmen Gómez-Guillén

Nanoencapsulation of an active peptidic fraction from sea bream scales collagen

Sea bream scales were subjected to enzymatic hydrolysis with Esperase, and a peptide fraction with a molecular mass <3kDa (F3) was isolated by ultrafiltration. F3 was encapsulated in nanoliposomes made of partially purified phosphatidylcholine (PC). Concentrations of 3.1% and 1mg/ml for PC and F3, respectively, were established as the best entrapment protocol by response surface methodology. The liposomes entrapment efficiency and zeta potential were 74.6±0.9% and -40.8±0.67mV, respectively. The liposome size ranged from 66.2 to 214nm, with a mean diameter of 90.3nm and a polydispersity index of 0.25. The antioxidant activity and ACE inhibitory activity of the encapsulated peptide fraction (L-F3) remained constant after 8days at 4°C. Encapsulation preserved the biological activities of F3, and could therefore be an alternative to improve the stability of these compounds when applied to a food product.

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.

Edible Films and Coatings: Fundamentals and Applications

Edible films and coatings : fundamentals and applications , Edible films and coatings : fundamentals and applications , کتابخانه مرکزی دانشگاه علوم پزشکی تهران

The effect of combined traditional and novel treatments on oxidative status of dolphinfish (Coryphaena hippurus) and sardine (Sardina pilchardus) muscle lipids.

Fish is rich in polyunsaturated fatty acids with beneficial effects on human health; however, these lipids are very sensitive to auto-oxidation reactions, leading to loss of nutritional and sensory quality. The effect of traditional (brining, smoking) and novel (addition of polyphenolic extracts, high pressure) preservation processes on the antioxidant/oxidative status of muscle lipids from dolphinfish and sardine was studied. Brining with oregano or rosemary aqueous extracts, as well as smoking, gave rise to deposition of phenolic compounds (9–42, 1.5–4.5 and 0.4–2.3 µg phenol/g for smoked, oregano-brined and rosemary-brined samples, respectively) in the muscle of both fish species. The antioxidant activity, as measured by ferric reducing ability, was also improved after brining with antioxidant extracts or smoking, results ranging from 8.9 to 82 mM FeSO4 · 7H2O equivalents/mg muscle depending on the treatment and the fish species. Consequently, fish lipid oxidation (as measured by thiobarbituric acid reactive substances) derived from brining and pressurizing, applied alone or in combination, was reduced between 6.6 and 69.8% depending on the treatment and the fish species. The combination of brining with oregano extract and light smoking showed an additional antioxidant effect, as compared with that obtained by smoking, on reducing sardine lipid oxidation derived from brining and pressurizing.

Bioaccessibility and antimicrobial properties of a shrimp demineralization extract blended with chitosan as wrapping material in ready-to-eat raw salmon

A shrimp extract (SME) obtained from the mild-acid demineralization treatment of shrimp shells to produce chitosan was collected. It was mainly composed of fat (≈73%), protein (≈19%), and ash (≈9%) and contained considerable amounts of calcium (≈1.9 g/100 g), astaxanthin (≈30 mg/100 g) and unsaturated fatty acids (≈27% MUFA, ≈39% PUFA). The SME was used in combination with chitosan for wrapping raw salmon to produce a ready-to-eat product enriched in calcium. No significant changes in hardness were found, as compared to the unwrapped salmon. Estimated intakes of bioaccessible calcium increased significantly by 3.6-fold, whereas intake of bioaccessible fat was reduced by 15%. SFA were the main fatty acid group reduced (≈80%), whereas MUFA and PUFA were only reduced by ≈20% each. Total viable counts, pseudomonads, enterobacteria, and specific fish spoilers were reduced by 2-4 log CFU/g in wrapped sample during the chilled storage period (19 days).

Glycosaminoglycans from grey triggerfish and smooth hound skins: Rheological, Anti-inflammatory and wound healing properties

The present study aims to evaluate for the first time the wound healing and in vivo anti-inflammatory effects of glycosaminoglycans from skins of smooth hound (SHSG) and grey triggerfish (GTSG). Thermal analysis of GTSG and SHSG was evaluated using differential scanning calorimetry (DSC). The rheologie properties and water absorption capacity of two gels prepared from SHSG and GTSG were also studied. The application of GTSG and SHSG based gels on dermal full-thickness excision wounds in a mouse model, enhanced significantly wound healing activity and a total closure was achieved after eleven days of wound induction for SHSG. Further, histological examination of biopsies showed advanced tissue regeneration, characterized by the presence of well-organized stratum of both derma and epidermis. The anti-inflammatory evaluation of GTSG and SHSG in mice showed a significant inhibition of edema paw, after 5 h of carrageenan injection. The edema inhibition was 91.6% and 90% for SHSG and GTSG, respectively at the dose of 50 mg/kg. Furthermore, the histological evaluation and the superoxide dismutase, catalase and malondialdehyde level in muscle tissue were investigated. In summary, this work demonstrates that both GTSG and SHSG could be promising drugs with good wound healing and anti-inflammatory effects in animal model.

Encapsulation of antioxidant sea fennel (Crithmum maritimum) aqueous and ethanolic extracts in freeze-dried soy phosphatidylcholine liposomes

Soy phosphatidylcholine liposomes encapsulating increasing concentrations of two sea fennel extracts (aqueous and ethanolic) prepared by ultrasonication were freeze-dried, using glycerol as lyoprotectant. Particle properties, water dispersibility, colour, thermal properties and antioxidant capacity (radical scavenging capacity, ferric ion reducing power, Folin-reactive substances) of the liposomal preparations were determined. The freeze-drying process caused an overall increase in particle size and polydispersity index, while the zeta-potential became more electronegative. Both sea fennel extracts were rich in chlorogenic acid (42.61 and 58.48 mg/g for the aqueous and ethanolic extracts, respectively) and showed great antioxidant activity. Vitamin C was identified in the aqueous extract, whereas rutin and rosmarinic acid in the ethanolic one. The entrapment efficiency, determined in the liposomes prepared at the highest extract concentration, was 65.6% and 49.1% for the aqueous extract and the ethanolic extract, respectively. The liposomal antioxidant activity and total phenolic content followed a linear increasing tendency as a result of increasing the extract concentration, irrespective of the type of extract. Higher antioxidant activity was found in the liposomes loaded with the ethanolic extract, in a clear relationship to the greater amount of highly antioxidant phenolic compounds extracted, and also to their lower entrapment efficiency, which caused a greater amount of extract to remain outside the liposome. Both extracts were suitable for producing liposomes with antioxidant properties which could be dried and used to design functional foods.