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An edible coating was developed using gelatin extracted from the skin of gray triggerfish (Balistes capriscus) and applied to the fillet of the smooth‐hound shark (Mustelus mustelus). Moringa oleifera leaf extract was added to gelatin coating solution to improve its preservative properties. The phenolic profiles and antioxidant and antibacterial activities of M. oleifera extracts were determined. Phenolic acids constituted the largest group representing more than 77% of the total compounds identified in the ethanol/water (MOE/W) extract, among which the quinic acid was found to be the major one (31.48 mg/g extract). The MOE/W extract presented the highest DPPH• scavenging activity (IC50 = 0.53 ± 0.02 mg/ml) and reducing (Fe3+) power (EC0.5 = 0.57 ± 0.02 mg/ml), as well as interesting inhibition zones (20–35 mm) for the most tested strains. Coating by 3% of gelatin solution significantly reduced most deterioration indices during chilled storage, such as malondialdehyde (MDA), total volatile basic nitrogen (TVB‐N), weight loss, pH, and mesophilic, psychrophilic, lactic, and H2S‐producing bacterial counts. Interestingly, coating with gelatin solution containing MOE/W extract at 20 μg/ml was more effective than gelatin applied alone. Compared with the uncoated sample, gelatin‐MOE/W coating reduced the weight loss and MDA content by 26% and 70% after 6 days of storage, respectively. Texture analysis showed that the strength of uncoated fillet increased by 46%, while the strength of fillet coated with gelatin‐MOE/W only increased by 12% after 6 days of storage. Fish fillet coated with gelatin‐MOE/W had the highest sensory scores in terms of odor, color, and overall acceptability throughout the study period. [ABSTRACT FROM AUTHOR]

Astragalus gombo Coss. & Dur L. Ex-Bunge is an endemic species of Algerian arid and semi-arid regions, however, is commonly used in traditional medicines. The aerial part was extracted by 80/20 methanol/water and water. The first crude extract was fractionated by ethyl acetate, n-butanol and methanol. LC-ESI-MS analysis revealed 25 compounds among all fractions. The major identified phenolic acids in ethyl acetate (EAAg) fraction were the p-coumaric flowed by tans-ferulic acid (1315 and 370 µg/g extract, respectively). Moreover EAAg exhibited high amounts of flavonoides (cirsiliol and quercetin-3-O-galactoside by 1155 and 491 µg/g extract, respectively). EAAg fraction was the most effective antioxidant in all assays tested, followed by NBAg fraction. The EAAg exhibited higher antioxidant activity than positive control BHA. Excellent and significant linear correlations were displayed between phenolic compounds and antioxidant capacities. Hence, both of fractions enhanced the phagocytic activity by stimulating the reticuloendothelial system at different doses 50, 70 and 100 mg/kg compared. Results of anticoagulant activity assay revealed that AEAg, EAAg and NBAg prolonged prothrombin time and activated partial thromboplastin. Cytotoxicity assay of EAAg fraction against HeLa and Mcf-7 cells revealed an IC50 values 108.8±1.8 and 168.4±1.6µg/mL, respectively, after 48h of incubation. Hence, The EAAg fraction displayed significant selectivity index (SI) towards normal mouse liver cells Aml12. The results presented clearly that A. gombo have a potential to be used as a natural antioxidant, especially the EAAg fraction, as an original source of bioactive molecules with anti proliferative activities and immunopromising effects. [ABSTRACT FROM AUTHOR]

Abstract Microwave power effects (100, 300 and 450 W) on drying kinetics of green peas at an initial 3.06 kg water/kg DM (76.2% wb) was investigated. The density level of microwave power (W/g DM) affected the drying kinetics, bioactive substances and green peas color. The parabolic model was found to be the best in matching the experimental data of green pea drying kinetics. It is well known that microwave drying is mainly due to Darcy's law with the gradient of total pressure as the driving force. Thus, this parameter was used to identify the drying operation as being controlled by effective moisture diffusivity. The values obtained ranged between 1.69 and 5.36 × 10−9 m2/s. The activation energy was determined as 1.38 kW/kg, using the modified Arrhenius equation. Application of high microwave power resulted in decreased L* and b* values, and an increase of a* values. The LC-ESI-MS analysis of peas extracts led to the identification of 7 phenolic acids and 8 flavonoids. Interestingly, peas dried at 100 W had the highest phenolic content as well as the highest DPPH• radical-scavenging activity. Graphical abstract fx1 Highlights • Level of microwave power density affected the peas drying kinetics. • Results were fitted to six thin-layer drying models and the parabolic one gave the best fit. • Effective moisture diffusivity ranged between 1.69 and 5.36 × 10−9 m2/s. • LC-ESI-MS analysis allowed the identification of 7 phenolic acids and 8 flavonoids in peas. • Peas dried at 100 W showed the highest phenolic content and antioxidant activity. [ABSTRACT FROM AUTHOR]

Abstract This study aims to investigate the thermoprotective properties of Opuntia ficus-indica f. inermis. Extracts were prepared from cladodes (CE) and mesocarps (ME), then subjected to a spectrophotometric and LC-MS analyses. Lymphocytes were isolated from peripheral blood of non-stressed sheep, supplemented with CE, ME, betanin or α-tocopherol, and subjected to two thermal treatments: 40 and 41 °C, for 6 h. Viable lymphocytes and H 2 O 2 production were evaluated. The antioxidant activity of ME was 3.43 folds higher than CE. The LC-MS analysis of CE and ME allowed identifying 11 phenolic acids, 2 flavanones, 6 flavones, 3 flavonols and 1 betanin type betacyanin. Lymphocytes mortality increased linearly as function of the severity and the duration of heat stress. This mortality was correlated with H 2 O 2 production. At 41 °C, only ME allowed maintaining lymphocytes viability. Moreover, ME was more efficient than CE in reducing H 2 O 2 production. This thermoprotection was ensured by betaxanthin and betacyanin pigments. Interestingly, betanin was more efficient than α-tocopherol in preventing hyperthermia-induced lymphocytes' mortality. We report here for the first time the thermoprotective properties of cladodes and mesocarps of Opuntia ficus-indica f. inermis. Betanin was able to maintain lymphocyte viability through reducing H 2 O 2 production, and therefore the oxidative-induced heat stress. Graphical abstract fx1 Highlights • Heat stress increases H 2 O 2 production and results in oxidative stress. • Hyperthermic lymphocytes' mortality was correlated with H 2 O 2 production. • Opuntia ficus-indica mesocarp allows lymphocytes thermoprotection by reducing H 2 O 2 production. • Betanin is more efficient than α-tocopherol in maintaining lymphocytes viability under heat stress conditions. [ABSTRACT FROM AUTHOR]

• Profiling of aerial part extracts of rare Tunisian Salvia species by HPTLC-EDA-HRMS. • Biological, biochemical and chemical profiles obtained for different species in comparison. • Characteristic profiles can be used to confirm authenticity of different species. • Bioactive substance zones attributed to tanshinones, triterpenoids and phenolic acids present. • Caffeic acid derivative as well as oleanolic and ursolic acids found in S. verbenaca extract. Aerial parts of the rare species Salvia aegyptiaca L. and S. verbenaca L. were collected from arid habitats in southern Tunisia. Their polar (ethanol−water) and mid-polar (ethyl acetate) extracts were analyzed non-targeted via a developed high-performance thin-layer chromatography profiling hyphenated with 12 effect-directed assays and 8 different physico-chemical detections. Bioactive compound zones were observed with inhibiting activities on α-glucosidase, ß-glucosidase, ß-glucuronidase, acetylcholinesterase, butyrylcholinesterase and tyrosinase, with radical scavenging (antioxidative) effects, and with activities against Gram-negative and Gram-positive bacteria. The effect-directed profile patterns showed common bioactive zones for different collection sites of the same species and distinct differences between species. Such characteristic profiles can be used to prove authenticity. Genotoxic, estrogen-like and androgen-like compounds were not detected even at higher amounts applied (for extracts from 1.6 mg sample). In the physico-chemical profiling, further organic substances were selectively detected, which highlighted the complexity of the multi-component mixture. The Tunisian sage profiles were further compared to the frequently used S. folium L. and S. officinalis L. leaves, and to reference mixtures containing phenolic acids and tanshinones. Selected bioactive zones in the S. verbenaca extracts were characterized by high-resolution mass spectrometry, and some mass signals were attributed to a caffeic acid derivative and to oleanolic and ursolic acids. Such effect-directed non-target profiling allows straightforward comparison not only of sage but of plant extracts in general. [ABSTRACT FROM AUTHOR]