Potential of essential oils for protection of Couscous against Aspergillus flavus and aflatoxin B1 contamination

 Food Control, 145, 109474, 2023

Our study was aimed to evaluate antifungal, antiaflatoxin, and antioxidant potential of Mentha pulegium, Myrtus communis, and Mentha piperita essential oils (EOs). The EOs showed efficacy as a couscous preservative. A total of 387 fungal species were isolated from Couscous samples, with Aspergillus flavus BN (20) which is identified as the highest aflatoxin producer. The minimum inhibitory concentration (MIC) of M. pulegium and M. communis EOs against the toxigenic strain of A. flavus BN (20) determined to be 4.00 μL/mL, whereas the MIC of M. piperita was 3.50 μL/mL. The EOs inhibited the aflatoxin B1 production at lower concentrations. The EOs showed fungitoxicity against wide-ranging of fungi and high antioxidant activity. The IC50 value of the oils ranged between 3.27 and 4.31 μL/mL. EOs may be able to contribute preservation of food commodities against quantitative and qualitative losses. During fumigation assays in Algerian traditional food system (Couscous), the three EOs showed protection of Couscous from A. flavus contamination indicating their efficacy as sustainable fumigant in food systems.

Enhancement of bioavailability and bioactivity of diet-derived flavonoids by application of nanotechnology

 Crit. Rev. Food Sci. Nut. 63 (3) 378-393 (2023)

Flavonoids, which are a class of polyphenols widely existing in food and medicine, have enormous pharmacological effects. The functional properties of flavonoids are mainly distributed to their anti-oxidative, anticancer, and anti-inflammatoryeffects, etc. However, flavonoids’ low bioavailability limits their clinical application, which is closely related to their intestinal absorption and metabolism. In addition, because of the short residence time of oral bioactive molecules in the stomach, low permeability and low solubility in the gastrointestinal tract, flavonoids are easy to be decomposed by the external environment and gastrointestinal tract after digestion. To tackle these obstacles, technological approaches like microencapsulation have been developed and applied for the formulation of flavonoid-enriched food products. In the light of these scientific advances, the objective of this review is to establish the structural requirements of flavonoids for appreciable anticancer, anti-inflammatory, and antioxidant effects, and elucidate a comprehensive mechanism that can explain their activity. Furthermore, the novelty in application of nanotechnology for the safe delivery of flavonoids in food matrices is discussed. After a literature on the flavonoids and their health attributes, the encapsulation methods and the coating materials are presented.

Effects of alginates on the growth, haematological, immunity, antioxidant and pro-inflammatory responses of rabbits under high temperature

 Res. Vet. Sci. 155, 36-43, 2023

Heat stress (HS) is one of the most severe hurdles impacting rabbit growth, immunity, homeostasis, and productivity. Alginate oligosaccharides (AOS) have considerable beneficial effects due to their plausible antioxidant and immune-stimulatory properties. This work was planned to explore the preventive function of AOS as a new bio-feed additive against the harmful effects caused by environmental HS on growing rabbits. Rabbits were allotted in four experimental groups (25 animals in each group) and fed on a basal diet supplemented with 0.0 (AOS0), 50 (AOS50), 100 (AOS100), and 150 (AOS150) mg AOS/kg diet reared under summer conditions. Dietary AOS supplementation improved significantly (P ≤ 0.001) feed conversion rate, while both AOS100 and AOS150 significantly (P ≤ 0.001) enhanced the final body weight and body weight gain. All AOS addition significantly increased nitric oxide and lysosome activity and significantly reduced interferon-gamma (IFNγ) compared with those in the control group. Tumor necrosis factor α (TNFα), interleukin1β (IL-1β), myeloperoxidase and protein carbonyl levels were significantly reduced in rabbits fed diets containing AOS (100 and 150 mg/kg) compared with those in the control group under heat stress conditions. In addition, glutathione (GSH) and catalase (CAT) were significantly (P ≤ 0.001) improved with increasing AOS dietary levels compared with the control group. Still, total antioxidant capacity (TAC), malondialdehyde (MDA), hematocrit, mean corpuscular volume (MCV), eosinophils, and lymphocytes did not change. Erythrocyte's indices improved significantly (P ≤ 0.001), while neutrophils and white blood cell counts were decreased by dietary AOS inclusion. Immunological (IgM and IgG) were markedly reduced in AOS-treated groups compared with the control group. The current investigation exemplified that AOS as a novel bio-feed additive that could be an effective strategy to extenuate prejudicial effects in heat-stressed rabbits via enhancing immunity, and antioxidant defence system, further regulating the inflammation cytokines.

Effects of alginates on the growth, haematological, immunity, antioxidant and pro-inflammatory responses of rabbits under high temperature

 Res. Vet. Sci. 155, 36-43, 2023

Heat stress (HS) is one of the most severe hurdles impacting rabbit growth, immunity, homeostasis, and productivity. Alginate oligosaccharides (AOS) have considerable beneficial effects due to their plausible antioxidant and immune-stimulatory properties. This work was planned to explore the preventive function of AOS as a new bio-feed additive against the harmful effects caused by environmental HS on growing rabbits. Rabbits were allotted in four experimental groups (25 animals in each group) and fed on a basal diet supplemented with 0.0 (AOS0), 50 (AOS50), 100 (AOS100), and 150 (AOS150) mg AOS/kg diet reared under summer conditions. Dietary AOS supplementation improved significantly (P ≤ 0.001) feed conversion rate, while both AOS100 and AOS150 significantly (P ≤ 0.001) enhanced the final body weight and body weight gain. All AOS addition significantly increased nitric oxide and lysosome activity and significantly reduced interferon-gamma (IFNγ) compared with those in the control group. Tumor necrosis factor α (TNFα), interleukin1β (IL-1β), myeloperoxidase and protein carbonyl levels were significantly reduced in rabbits fed diets containing AOS (100 and 150 mg/kg) compared with those in the control group under heat stress conditions. In addition, glutathione (GSH) and catalase (CAT) were significantly (P ≤ 0.001) improved with increasing AOS dietary levels compared with the control group. Still, total antioxidant capacity (TAC), malondialdehyde (MDA), hematocrit, mean corpuscular volume (MCV), eosinophils, and lymphocytes did not change. Erythrocyte's indices improved significantly (P ≤ 0.001), while neutrophils and white blood cell counts were decreased by dietary AOS inclusion. Immunological (IgM and IgG) were markedly reduced in AOS-treated groups compared with the control group. The current investigation exemplified that AOS as a novel bio-feed additive that could be an effective strategy to extenuate prejudicial effects in heat-stressed rabbits via enhancing immunity, and antioxidant defence system, further regulating the inflammation cytokines.

Potential of essential oils for protection of Couscous against Aspergillus flavus and aflatoxin B1 contamination

 Food Control, 145, 109474, 2023

Our study was aimed to evaluate antifungal, antiaflatoxin, and antioxidant potential of Mentha pulegium, Myrtus communis, and Mentha piperita essential oils (EOs). The EOs showed efficacy as a couscous preservative. A total of 387 fungal species were isolated from Couscous samples, with Aspergillus flavus BN (20) which is identified as the highest aflatoxin producer. The minimum inhibitory concentration (MIC) of M. pulegium and M. communis EOs against the toxigenic strain of A. flavus BN (20) determined to be 4.00 μL/mL, whereas the MIC of M. piperita was 3.50 μL/mL. The EOs inhibited the aflatoxin B1 production at lower concentrations. The EOs showed fungitoxicity against wide-ranging of fungi and high antioxidant activity. The IC50 value of the oils ranged between 3.27 and 4.31 μL/mL. EOs may be able to contribute preservation of food commodities against quantitative and qualitative losses. During fumigation assays in Algerian traditional food system (Couscous), the three EOs showed protection of Couscous from A. flavus contamination indicating their efficacy as sustainable fumigant in food systems.

Potential of essential oils for protection of Couscous against Aspergillus flavus and aflatoxin B1 contamination

Food Control, 145, 109474, 2023

Our study was aimed to evaluate antifungal, antiaflatoxin, and antioxidant potential of Mentha pulegium, Myrtus communis, and Mentha piperita essential oils (EOs). The EOs showed efficacy as a couscous preservative. A total of 387 fungal species were isolated from Couscous samples, with Aspergillus flavus BN (20) which is identified as the highest aflatoxin producer. The minimum inhibitory concentration (MIC) of M. pulegium and M. communis EOs against the toxigenic strain of A. flavus BN (20) determined to be 4.00 μL/mL, whereas the MIC of M. piperita was 3.50 μL/mL. The EOs inhibited the aflatoxin B1 production at lower concentrations. The EOs showed fungitoxicity against wide-ranging of fungi and high antioxidant activity. The IC50 value of the oils ranged between 3.27 and 4.31 μL/mL. EOs may be able to contribute preservation of food commodities against quantitative and qualitative losses. During fumigation assays in Algerian traditional food system (Couscous), the three EOs showed protection of Couscous from A. flavus contamination indicating their efficacy as sustainable fumigant in food systems.

Phytochemical and multi-biological characterization of two Cynara scolymus L. varieties: A glance into their potential large scale cultivation and valorization as bio-functional ingredients

 Industrial Crops and Products, 2022, 178, 114623

Artichoke leaf (Cynarae folium) extracts are used as traditional herbal medicinal products to treat a wide range of human ailments, being widely commercialized as nutraceutical or pharmaceutical preparations. In the current study, the hydromethanolic dried leaf extracts of Cynara scolymus L. var. major Brotero and C. scolymus L. var. redonensis N.H.F. Desp. were phytochemically and biologically investigated. The liquid chromatography high-resolution tandem mass spectrometry (LC-HRMS/MS) metabolite profiling showed a complex composition, with phenolic acids (mostly mono- and di-caffeoylquinic acids), flavonoids and sesquiterpene lactones as the most representative classes. The strong antioxidant activity of the two C. scolymus varieties was evidenced in DPPH [64.84–65.21 mg trolox equivalents (TE)/g] and ABTS (86.39–95.55 mg TE/g) radical scavenging, cupric (160.49–171.07 mg TE/g) and ferric (71.47–78.95 mg TE/g) reducing capacity, metal chelating and phosphomolybdenum assays. In addition, the two extracts also displayed anti-enzymatic effects, as assessed in cholinesterase, tyrosinase, glucosidase and amylase tests. Lastly, the artichoke samples (at the concentration of 20 μg/mL) proved a very potent inhibition of the production of several pro-inflammatory cytokines, namely interleukin (IL)-1β [7.55–15.75% of lipopolysaccharide (LPS) + cells], IL-8 (11.72–13.46% of LPS + cells) and tumor necrosis factor (TNF)-α (4.07–10.35% LPS + cells), in LPS-stimulated human neutrophils. Overall, the results of our study indicate that the two C. scolymus varieties could be regarded as a rich source of biologically active compounds, opening thus the perspectives for their future large scale cultivation and valorization as bio-functional ingredients with putative antioxidant, anti-enzymatic and anti-inflammatory effects.

Polyphenols: A first evidence in the synergism and bioactivities

 Food Rev. Int. 2022

Polyphenols are natural compounds and the most plentiful with synergistic properties contributing to potential health benefits. This review describes the synergistic interactions of polyphenolic compounds; as yet, no literature review has been undertaken to consider the experimental evidence of synergistic effects of polyphenols. The polyphenolic compounds claimed to have synergistic activities are highly effective against oxidation, peptic ulcers, myocardial infarction, tumors, and a variety of other conditions. In addition, anticancer activity via apoptosis and antibacterial, antifungal, anti-inflammatory, and estrogenic behaviors have also been reported. Apart from the synergistic effects of polyphenols, this review also illustrates their specific health benefits too and bioavailability in humans. The toxicity of some polyphenolic agents, including antinutritional effects, chronic nephrotoxicity, reduction in net protein utilization and antiluteinizing hormone, and tumor development, is also evaluated. Synergistic treatment approaches may be effective in the treatment of many diseases. These findings provide information about the benefits of polyphenol compounds in combination, which could be useful for future studies.

Cellular antioxidant potential and inhibition of foodborne pathogens by a sesquiterpene ilimaquinone in cold storaged ground chicken and under temperature-abuse condition

 Food Chem. 373, Part A, 131392, 2022

A sesquiterpene quinone, ilimaquinone, was accessed for its cellular antioxidant efficacy and possible antimicrobial mechanism of action against foodborne pathogens (Staphylococcus aureus and Escherichia coli) in vitro and in vivo. Ilimaquinone was found to be protective against H2O2-induced oxidative stress as validated by the reduction in the ROS levels, including increasing expression of SOD1 and SOD2 enzymes. Furthermore, ilimaquinone evoked MIC against S. aureus and E. coli within the range of 125–250 µg/mL. Ilimaquinone established its antimicrobial mode of action against both tested pathogens as evident by bacterial membrane depolarization, loss of nuclear genetic material, potassium ion, and release of extracellular ATP, as well as compromised membrane permeabilization and cellular component damage. Also, ilimaquinone showed no teratogenic effect against zebrafish, suggesting its nontoxic nature. Moreover, ilimaquinone significantly reduced the S. aureus count without affecting the sensory properties and color values of cold-storaged ground chicken meat even under temperature abuse condition.