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Bilayer antibacterial films were prepared using electrospun polylactic acid (PLA)/chitosan (Ch) nanofiber on low‐density polyethylene (LDPE)/PLA films. Blends of Ch and PLA with the selected ratios of 5.0%, 10.0%, 15.0%, and 20.0% Ch were electrospun on the surface of LDPE/PLA composite film. Scanning electron microscopic images indicated a smooth and bead‐free surface for all composite nanofibers with a diameter range from 50–200 nm. Fourier transform infrared spectra depict the presence of PLA and CH in the nanofiber. Hydrophobicity analysis showed that the PLA/Ch layer increase the hydrophobicity of bilayer films. The water vapor permeabilities of bilayer films were lower than those of LDPE/PLA film. The presence of PLA/Ch nanofiber layer resulted in the reduction in the oxygen permeability of bilayer films. When Ch content reached 10.0%, the bilayer films showed antibacterial activities against Escherichia coli and Staphylococcus aureus. Novelty impact statement: Blends of chitosan and polylactic acid (PLA) was electrospun on to the surface of a low‐density polyethylene (LDPE)/PLA film to produce bilayer antibacterial films. Electrospun nanofiber layers improved the antibacterial properties of the films and also reduced the oxygen and water vapor permeability levels of LDPE/PLA composite films without major interferences with their intrinsic physical and barrier properties. [ABSTRACT FROM AUTHOR]

In the present study, two methods were used to extract oil from seeds of Sardasht black grapewith normal-hexane and cold press.The average efficiency rate of oil extraction by the formermethod was obtained at 12.6% and that of the latter was 17.2%. Meanwhile, in order to examine the quality of the oilsextracted by these two methods, peroxide value, acid value, sapponification number, total phenolic contents, antioxidant power and iodine valuewere evaluated. The compositions of fatty acids of oil samples extracted by both methods were identified using gas chromatography technique. Similarly, the triglyceride composition, phospholipids composition and tocopherol values of the oil samples extracted were studied. The results showed that the dominant fatty acids available in cold-pressand solvent extraction methods were linoleic acid at 63.5 and 66.7% and oleic acid at 19.7 and 17.7%, respectively. Moreover, in both extracted oil samples, trilinoleinwith values at 28.9 and 28.5%, oleoyldilinolein with values at 19.5 and 20.5%and palmitoyldilinolein with values at 18.5 and 17.1% were the dominant triglyceride compounds, respectively. The value of phospholipids composition in the oil extracted by cold-presswas 61 mg/kg and that of solventextractionwas 45mg/kg. The dominant values of tocotrienol compositions in oil samples extracted by coldpresswere gamma tocotrienol and alpha tocotrienol at 66.0 and 23.1%, respectively and the corresponding values in oil samples extracted by solvent method were at 33.3 and 53.0%, respectively. [ABSTRACT FROM AUTHOR]

BACKGROUND: Oxalic acid is a common antinutrient in the human diet, found in large quantities in spinach. However, spinach is highly regarded by vegetable producers because of its nutritional content and economic value. One of the primary purposes of spinach‐breeding programs is to improve the nutritional value of spinach by adjusting oxalate accumulation. Knowledge of the biosynthetic patterns of oxalic acid, and its different forms, is important for a better understanding of this process. RESULTS: We found three biosynthetic patterns of accumulation and concentration of oxalates. Two of them are related to the maximum type and one is related to the minimum type. We also developed a general model of variations in these compounds in the genotypes that were studied. CONCLUSION: This study introduced a unique type of spinach with high oxalate accumulation, which could be particularly suitable for consumption. This had the highest ratio of insoluble oxalate to soluble oxalate. It also accumulated more ascorbic acid (AA) than other types. Our findings in this study also indicate a small role for AA as a precursor to oxalate production in spinach, possibly confirming the significant role of glyoxylate as the most critical precursor in this plant. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Different sources of nitrogen fertilizers are being used in olive orchards, of which urea is widely used by olive growers. However, nano-chelated nitrogen (nano-N) is a newly found feature of the fertilizer with very little known information. In the current research, the impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. 'Zard' during two consecutive seasons were investigated. The olive trees were sprayed with 2.21 g (U1) and 2.95 g (U2), and 6 g nano-N1 and 8 g nano-N2 at several phenological stages of olive tree. The detailed observations showed that U1 significantly increased fruit yield. Monounsaturated fatty acid and the ratio of oleic acid to linoleic acid were increased by the nitrogen treatments, especially with nano-N2, whereas it decreased in the case of saturated fatty acid and polyunsaturated fatty acids. The application of both fertilizer sources improved the leaf mineral compositions as well as the oil quality such as free fatty acids, peroxide activity, K232 and K270 extinction coefficients, the chlorophyll and carotenoid pigments. Total phenolic content of the oil in olive trees sprayed with urea was lower than those treated with nano-N. In contrast, the oil antioxidant capacity was high in those trees treated with nano-N. Overall, the results showed that nanofertilizer, especially nan-N2 treatment rather than urea, is an effective approach to improve oil quality. [ABSTRACT FROM AUTHOR]