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.

Traditional use, phytochemistry, toxicology, and pharmacological properties of Lavandula dentata L.,: A comprehensive review

 South Africa J. Botany, 154- 67-87, 2023

Lavandula dentata L. is a medicinal plant belonging to the Lamiaceae family, frequently used in traditional medicine to treat various pathologies such as diabetes, inflammation, microbial infections, and other disordors. The present work aims to explore this medicinal plant by highlighting its ethno-medicinal uses, its phytochemical characteristics, as well as its pharmacological and industrial properties on a global scale.

Thus, in this review, the highlighted properties are reported to explore possible therapeutic pathways of L. dentata. As reported, this medicinal species is rich in different phytochemicals belonging to several chemical families, including phenolic acids, flavonoids, and terpenoids. Indeed, L. dentata chemical compounds are characterized by several promising biological and pharmacological properties. These bioactivities include antibacterial, antifungal, antioxidant, anti-diabetic, anticancer, anti-inflammatory effects, etc. In fact, and even at low concentrations, L. dentata essential oils (EOs) and organic extracts specifically inhibit enzymes, membrane or intracellular receptors, proteins or signaling pathways involved in the genesis of these pathologies. The findings of this work revealed that the pharmacological activities of L. dentata confirm the importance, the diversified use, and the effectiveness of this plant in the traditional remedies of many diseases. Nevertheless, pharmacokinetic validation and toxicological examinations are required to detect any possible toxicity for future clinical trials.

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.

Use of Spectroscopic Techniques to Monitor Changes in Food Quality during Application of Natural Preservatives: A Review

 Antioxidants 2020, 9(9), 882

DOI:10.3390/antiox9090882

Consumer demand for food of high quality has driven research for alternative methods of food preservation on the one hand, and the development of new and rapid quality assessment techniques on the other hand. Recently, there has been a growing need and interest in healthier food products, which has led to an increased interest in natural preservatives, such as essential oils, plant extracts, and edible films and coatings. Several studies have shown the potential of using biopreservation, natural antimicrobials, and antioxidant agents in place of other processing and preservation techniques (e.g., thermal and non-thermal treatments, freezing, or synthetic chemicals). Changes in food quality induced by the application of natural preservatives have been commonly evaluated using a range of traditional methods, including microbiology, sensory, and physicochemical measurements. Several spectroscopic techniques have been proposed as promising alternatives to the traditional time-consuming and destructive methods. This review will provide an overview of recent studies and highlight the potential of spectroscopic techniques to evaluate quality changes in food products following the application of natural preservatives.

Antioxidant and antimicrobial properties of encapsulated guava leaf oil in hydroxypropyl-beta-cyclodextrin

Industrial Crops and Products
https://doi.org/10.1016/j.indcrop.2017.10.027

The essential oil from guava leaves has low physicochemical stability and low solubility in water, what limits its application in food formulations. This study aimed to characterize the physicochemical properties and the antioxidant and antimicrobial activities of encapsulated guava leaf oil in hydroxypropyl-β-cyclodextrin (HPβCD). Inclusion complex formation of guava leaf oil and HPβCD was determined by several techniques. Antioxidant activity of encapsulated guava leaf oil was more stable to sunlight exposure than free guava leaf oil by 26–38%. The antibacterial activity of guava leaf oil against Staphylococcus aureus and Escherichia coli was improved by 4 and 2 times after encapsulation in HPβCD, respectively.

Physico-chemical characterization and evaluation of bio-efficacies of black pepper essential oil encapsulated in hydroxypropyl-beta-cyclodextrin

Food Hydrocolloids

https://doi.org/10.1016/j.foodhyd.2016.11.014

Encapsulation of essential oils with cyclodextrins can protect their active compounds from environmental conditions and improve their aqueous solubility, hence increasing their functional capabilities as additives. The purpose of this study was to characterize the physico-chemical properties and bio-efficacies, antioxidant and antibacterial activities, of the encapsulated black pepper essential oil in hydroxypropyl-β-cyclodextrin (HPβCD), in comparison with the major ingredient in the oil, β-caryophyllene. The difference in encapsulation efficiency of the pure compound and the black pepper oil results from the presence of other components in the black pepper oil such as limonene, δ-3-carene and pinene. Although the inclusion complexes increase their stability, they gave slightly lower antioxidant activity as a result of the HPβCD was blocking the functional groups of active compounds during reaction with DPPH radicals. Instead, after encapsulated in HPβCD, the antibacterial activity of black pepper oil was improved by 4 times against both S. aureus and E. coli.

Encapsulation of yarrow essential oil in hydroxypropyl-beta-cyclodextrin: physiochemical characterization and evaluation of bio-efficacies

CyTA - Journal of Food

http://dx.doi.org/10.1080/19476337.2017.1286523

Essential oil from yarrow (Achillea millefolium L. s. l.) has a broad spectrum of pharmacological activities. However, active chemical components of yarrow oil are sensitive to environmental factors such as, light, oxygen and temperature. Encapsulation of essential oil offers solutions for the limitation. Yarrow oil was encapsulated in hydroxypropyl-β-cyclodextrin (HPβCD) through freeze-drying technique with encapsulation efficiency of 45%. Inclusion complex formation was examined by scanning electron microscope, Fourier transformed infrared spectroscopy and UV–vis analysis and phase solubility study. Yarrow oil gave strong antioxidant activity of 72% DPPH scavenging at 50 μg/mL. HPβCD could protect active compounds of essential oil and retained antioxidant activity after sunlight exposure. Yarrow oil also exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli with the minimum inhibitory concentration (MIC) values of 250 μg/mL and 500 μg/mL, respectively. The antibacterial efficacy was much improved after encapsulation against both S. aureus and E. coli with the MIC value of 62.5 μg/mL.

Physico-chemical characterization and evaluation of bio-efficacies of black pepper essential oil encapsulated in hydroxypropyl-beta-cyclodextrin

Food Hydrocolloids

http://dx.doi.org/10.1016/j.foodhyd.2016.11.014

Encapsulation of essential oils with cyclodextrins can protect their active compounds from environmental conditions and improve their aqueous solubility, hence increasing their functional capabilities as additives. The purpose of this study was to characterize the physico-chemical properties and bio-efficacies, antioxidant and antibacterial activities, of the encap- sulated black pepper essential oil in hydroxypropyl-β-cyclodextrin (HPβCD), in comparison with the major ingredient in the oil, β-caryophyllene. The difference in encapsulation efficiency of the pure compound and the black pepper oil results from the presence of other components in the black pepper oil such as limonene, δ-3-carene and pinene. Although the inclusion complexes increase their stability, they gave slightly lower antioxidant activity as a result of the HPβCD was blocking the functional groups of active compounds during reaction with DPPH radicals. Instead, after encapsulated in HPβCD, the antibacterial activity of black pepper oil was improved by 4 times against both S. aureus and E. coli.