Enhancing functional buffalo yogurt: Improving physicochemical properties, biological activities, and shelf life using marjoram and geranium essential oils.

The use of essential oils (EO) has attracted interest in the food industry because of their wide range of beneficial properties. In this study, a new functional yogurt was developed using 2 EO, marjoram and geranium, at 3 different concentrations (0.2%, 0.4%, and 0.6% vol/vol). The physicochemical properties, including syneresis, viscosity, pH, and chemical composition; bioactivities, including antioxidant activity, anticancer and antibacterial effects, total phenolic content (TPC), and total flavonoid content (TFC); and sensory characteristics of the developed yogurt were evaluated. The findings indicated that the yogurts fortified with 0.6% marjoram or geranium exhibited higher viscosity and lower syneresis compared with other treatments. The yogurt supplemented with 0.6% marjoram displayed significant antibacterial activity against Listeria monocytogenes, Staphylococcus aureus, Salmonella typhimurium, and Escherichia coli. In addition, the yogurt enriched with geranium and marjoram oils at a concentration of 0.6% had notably significant (P < 0.05) higher TFC levels compared with the control sample and other concentrations. In the same context, in terms of TPC, yogurt supplemented with 0.6% marjoram displayed significantly (P < 0.05) elevated levels in comparison to the other samples tested. Yogurt enriched with marjoram oil exhibited noteworthy antioxidant activity, followed by geranium oil, compared with the control samples. The yogurt supplemented with 0.6% marjoram demonstrated strong radical scavenging activity, and the yogurt fortified with 0.6% geranium showed higher anticancer activity against HepG2 human liver carcinoma cells and oxidative stress enzyme activities. Among the various concentrations of EO tested, the yogurts fortified with 0.6% marjoram or geranium EO exhibited the most favorable outcomes, followed by 0.4% marjoram or geranium. To summarize, geranium and marjoram EO can be used as a potential nutritious ingredient and as a natural preservative for milk and related products.

Lemon peel essential oil and its nano-formulation to control Agrotis ipsilon (Lepidoptera: Noctuidae).

Due to excessive use of synthetic pesticides the pest resistance developed along with pesticide residues accumulation in crops. Therefore, many nations are switching from chemical-based agriculture to "green" agriculture for pest control. The destructive pest black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), is a polyphagous species that economically lead to extensive loss of a broad range of crops including corn, cotton, wheat, and many vegetables through the damage of foliar and roots. In this study, lemon peel essential oil (LPEO) was subjected to nano-formulation using polyethylene glycol as nanocarrier. The lethal activity of LPEO and its nano-form (LPEO-NPs) were tested against A. ipsilon second larval instar using feeding bioassay at different concentrations. Growth and developmental parameters, including larval and pupal duration, larval and pupal mortality, malformations % and adult emergence were evaluated. Results showed that LPEO exhibited insecticidal activity and causes different levels of effects on the development of A. ipsilon according to its concentration and formulation. In addition, at 75 mg/ml LPEO and LPEO-NPs significantly increased the larval mortality to 80.00% and 90.00%, respectively. The overall data revealed that insecticidal toxicity of LPEO was increased by nano-formulation.