Plastic packaging has been widely criticized due to the environmental pollution it entails. Biopolymer‐based films could provide an interesting eco‐friendly alternative. This study aimed to investigate the effect of plasticizer type on the physicochemical and mechanical properties of gelatin, pectin, starch, gelatin/pectin, gelatin/starch, and starch/pectin‐based films. Films were prepared using the casting method. Among the six types of films studied, gelatin/pectin‐based film plasticized with sorbitol displayed the best functional properties. Tensile strength and elongation at break were 52.46 MPa and 19.80%; moisture content, water vapor permeability, and water resistance were 19.96%, 3.24 × 107 g s–1 m–1 Pa–1, and 19.96%, respectively. Mentha pulegium and Lavandula angustifolia essential oils were incorporated into the selected film and their effects on the film's characteristics were evaluated. The incorporation of essential oils resulted in films with enhanced antibacterial properties, lower water vapor permeability, and reduced mechanical properties. Practical applications Biopolymer‐based films have attracted widespread attention as an alternative to plastic packaging. In this study, we have demonstrated that gelatin/pectin‐based film plasticized with sorbitol at 30% displayed good mechanical and physicochemical properties. The incorporation of Mentha pulegium and Lavandula angustifolia essential oils into this matrix resulted in films with important antimicrobial activity and adequate mechanical and physicochemical characteristics. The selected combination could be used as bioactive packaging to preserve and prolong the shelf life of food.

The effect of gelatin-based edible coating incorporated with Mentha pulegium essential oil (MEO) on physicochemical (pH, titratable acidity (TA), weight loss, total soluble solids (TSS), and total phenolic content (TPC)), microbiological (total aerobic mesophilic flora (TAMF) and yeasts and moulds (YM)), and sensorial (color and firmness) characteristics of strawberries stored under refrigeration was studied. Strawberries were coated with gelatin alone (4%) and/or gelatin combined with two concentrations (0.5 and 1%) of MEO and stored at 4°C for 13 days. Gelatin coating and MEO combination significantly inhibited total flora and moulds and yeasts with comparison to control (uncoated strawberries) and had better hygienic quality at the end of storage. The effect was MEO concentration dependent. Our results also showed that the bioactive coating used in this investigation slowed down changes in pH, TA, weight loss, TSS, firmness, TPC, and color of strawberries. Gelatin coating incorporated with MEO at 1% protected at least 60% of strawberries from deterioration after 13 days of storage and could be used as bioactive packaging to prolong the shelf life and an alternative of pesticides use.

Fish gelatin‐pectin (GelExt/Pec) composite films incorporated with Mentha pulegium essential oil (MEO) and Lavandula angustifolia essential oil (LEO) at two concentrations (0.5% and 1.5%) were developed and their physicochemical, mechanical, and antimicrobial properties were determined. GelExt/Pec‐based film incorporated with 1.5% MEO (GelExt/Pec + 1.5% MEO) showed the highest antimicrobial activity against all bacterial strains tested. Incorporation of essential oils decreased significantly the tensile strength of all the films investigated. The film showing the best functional and antimicrobial properties (Gelext/Pec + 1.5% MEO) was used to prolong the shelf life of tilapia fillets under refrigeration. Control (unwrapped) and wrapped fillets were analyzed every 3 days in terms of microbiological (total viable count (TVC), psychrotrophic bacteria count (PC), lactic acid bacteria (LAB) and Enterobacteriaceae (ENT), and physicochemical parameters (total volatile base nitrogen [TVB‐N] and pH). Gelext/Pec + 1.5% MEO antimicrobial film retarded significantly (p < .05) the growth of TVC, LAB, PC, and ENT, throughout 12 days of storage compared with the control. Gelext/Pec + 1.5% MEO could be considered as an effective packaging to maintain the quality and extend the shelf life of tilapia fillets under refrigeration.

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Among the abiotic stresses, drought is the first environmental stress responsible for a decrease in agricultural production worldwide; it affects plants in various ways, including slowing down plant growth and disrupting its general physiology. Arbuscular mycorrhizal symbiosis and plant growth-promoting rhizobacteria (PGPR) are considered to be the bioameliorators of the plant’s resistance to water stress. The present study investigated the effects of inoculation with arbuscular mycorrhizal fungi (AMF) and PGPR on the water status and antioxidant enzyme activities of date palm seedlings grown under water stress conditions. The parameters related to the plant’s water status were significantly ( p < 0.05 ) higher in the plants treated with mycorrhizae and mycorrhizae + bacteria compared with their respective controls, especially under water stress conditions. The maximum proline content was obtained in plants inoculated with the AMF species and PGPR (combined) under severe water stress conditions reaching a value of 2.588 ± 0.034 in 25% field capacity, compared with 0.978 ± 0.024 for the control. In addition, the inoculated seedlings showed notably lower activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and glutathione S-transferase (GST) in response to severe water stress compared with nonmycorrhizal seedling. Overall, the arbuscular mycorrhizal symbiosis and PGPR bacteria inoculation could be promising methods to enhance date palm resistance against oxidative stress.