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Abnormal production of reactive oxygen species (ROS) is an undesirable event which occurs in plants due to stress. To meet this event, plants synthesize ROS-neutralizing compounds, including the non-enzymatic oxidant scavenger known as vitamin C: ascorbic acid (AsA). In addition to scavenging ROS, AsA modulates many vital functions in stressed or non-stressed plants. Thus, two-season (2018/2019 and 2019/2020) trials were conducted to study the effect of integrative treatment (seed soaking + foliar spray) using 1.0 or 2.0 mM AsA vs. distilled water (control) on the growth, seed yield, and oil yield of parsley plants under three sowing dates (SDs; November, December, and January, which represent adverse conditions of late sowing) vs. October as the optimal SD (control). The ion balance, osmotic-modifying compounds, and different antioxidants were also studied. The experimental layout was a split plot in a completely randomized block design. Late sowing (December and January) noticeably reduced growth traits, seed and oil yield components, and chlorophyll and nutrient contents. However, soluble sugar, proline, and AsA contents were significantly increased along with the activities of catalase (CAT) and superoxide dismutase (SOD). Under late sowing conditions, the use of AsA significantly increased growth, different yields, essential oil fractions, CAT and SOD activities, and contents of chlorophylls, nutrients, soluble sugars, free proline, and AsA. The interaction treatments of SDs and AsA concentrations indicated that AsA at a concentration of 2 mM was more efficient in conferring greater tolerance to adverse conditions of late sowing in parsley plants. Therefore, this study recommends 2.0 mM AsA for integrative (seed soaking + foliar spraying) treatment to prolong the sowing period of parsley seeds (from October up to December) and avoid damage caused by adverse conditions of late sowing. [ABSTRACT FROM AUTHOR]

Bioactive nanocomposites were constructed, containing chitosan (Cht), extracted from shrimps' wastes, and transformed into nanoparticles (NPs) using ionic-gelation. Selenium NPs (Se-NPs) were phytosynthesized using cinnamon (Cinnamomum zeylanicum) bark extract (CIE), characterized and evaluated with Cht-NPs as antimicrobial composites against bacterial food-borne pathogens "Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Listeria monocytogenes" and as potential edible coating (EC) basements. The CIE-phytosynthesized Se-NPs had well-distributed and spherical shapes with 23.2 nm mean diameter. The CIE, CIE/Se-NPs, and innovative CIE/Se/Cht-NP composites exhibited distinguished antibacterial actions toward the entire screened pathogens; CIE/Se/Cht-NP composite was significantly the most potent. The formulated ECs from CIE/Se/Cht-NP nanocomposites had matching antibacterial manner, which was strengthened with CIE/Se-NP percentage increments. Scanning micrographs indicated the attachment of CIE/Se-NPs to bacterial cells to cause their complete lysis and death after 10 h of exposure. CIE/Se/Cht-NP composites are proposed as effectual control agents toward food-borne pathogens using efficient biological carriers and eco-friendly phytosynthesis protocol. [ABSTRACT FROM AUTHOR]

The biopreservation, flavoring, and coloration of foodstuffs, e.g., seafoods, with natural plant derivatives are major demands for consumers and overseers. Different colored plant parts, i.e., Hibiscus sabdariffa calyces, Curcuma longa rhizomes, and Rhus coriaria fruits, were extracted and evaluated as biopreservatives, antimicrobial and colorant agents for fish surimi from Oreochromis niloticus. All colorant plant extracts (CPEs) exhibited strong antibacterial activities against screened pathogens, Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Pseudomonas aeruginosa. H. sabdariffa extract (HCE) was the most effectual antimicrobial CPEs. S. aureus was the most sensitive strain to CPEs, whereas S. typhimurium and P. aeruginosa were the most resistant strains. The exterior coloration of tilapia surimi with CPEs resulted in great bacterial count reduction in colored products; stored CPEs-colored surimi had enhanced sensorial attributes. HCE-exposed S. aureus indicated bacterial cell lyses in time-dependent manner. CPEs application as colorants and antibacterial and quality enhancing agents is recommended for seafoods' biopreservation. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a highly dangerous pathogen that causes lots of health problems. The resistant strains to methicillin (MRSA) are dangerously health threatens. Nine plant seeds’ extracts ( Alium ampeloprasum , Allium cepa , Brassica juncea , Lycium shawii , Nigella sativa , Ocimum basilicum , Peganum harmala , Phyllanthus emblica and Portulaca oleracea ) were evaluated as microbial inhibitor agents against S. aureus isolates, including MRSA strains. The crude extracts of L. shawii and P. emblica seeds proved to be the most active antimicrobials, against the entire S. aureus strains, using both quality and quantity assays for their bactericidal activity. Both L. shawii and P. emblica seeds contained remarkable amounts from active phytochemicals, alkaloids, phenolic compounds, tannins and flavonoids. P. emblica seeds were exceedingly rich sources of phenolic compound and flavonoids. The electron scanning micrographs of S. aureus cells, after exposure to plant seeds’ extracts, showed that bacterial cells were shrunk and became tiny, diminutive and dehydrated after 3 h and the entire cells were fully lysed, exploded or disrupted after 6 h of exposure to P. emblica extract; whereas exposure to L. shawii extract derived treated cells to lyse and combine with each other’s after 3 h then complete cell wall lysis was observed after 6 h of exposure. The applications of plant seeds’ extracts, for textile finishing and ointment formulation, confirmed their efficacy as potent applicable anti-MRSA agents. It may be recommended to apply plant seeds’ extract, e.g. P. emblica and L. shawii , as powerful antibacterial agents for the control of the skin and foodborne pathogenic bacteria, S. aureus , and their resistant MRSA strains. [ABSTRACT FROM AUTHOR]

BACKGROUND The ongoing postharvest loss in citrus fruits, due to fungal infection, is a chronic economic and agricultural problem. Most of citrus damage is caused by Penicillium spp., e.g. green mold ( P. digitatum) and blue mold ( P. italicum). Fungal chitosan, from Mucor rouxii, and plant extracts from cress seeds, olive leaves, pomegranate peels and senna pods, were evaluated as antifungal agents against the phytopathogenic fungi, P. digitatum and P. italicum, using in vitro qualitative and quantitative assays. RESULTS All natural agents tested exhibited potent antifungal activity; the most powerful agent was cress ( Lepidium sativum) seed extract, followed by pomegranate ( Punica granatum) peel extract. Fungal chitosan also had a remarkable fungicidal potentiality using both evaluation assays. Penicillium digitatum was generally more resistant than P. italicum toward all examined agents. The incorporation of each individual natural agent in coating material resulted in a great reduction in fungal growth and viability. The addition of chitosan combined with cress and pomegranate extracts, to the coating materials, prevented coated citrus fruit from decay by green and blue mold for a 2-week storage period. CONCLUSION Natural derivatives could be recommended as powerful antifungal alternatives to protect citrus fruits from postharvest fungal decay. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Anise is one of the plants with therapeutic potential, which is classified among the most important medicinal plants with interesting biological effects. Its components could be perceived so as "natural" and "safe" alternatives to antibiotics as well as they are applied in different industries such as food and cosmetic purposes. Selenium (Se) is an essential micronutrient, however, its importance to improve oil yield and quality of anise has not been adequately investigated, specifically under drought. Therefore, two successive seasons were conducted to investigate the effect of selenium foliar application upon anise plants under drought stress. Selenium was applied at three different concentrations (0.0 1.0 and 2.0 mM denoted Se0, Se1 and Se2, respectively) along with two levels of crop evapotranspiration (ET): Full irrigation, 100% of ET (FI) and 60% of ET (DI). The promotive effect of combinations of DI × Se1 or Se2 (for Fv/Fm, RWC%, and MSI% in the first season) and DI × Se2 (for Fv/Fm, and MSI% in the second season) were as similar as FI × Se2. Compared to the counterpart control treatment (DI × Se0), the highest increases in total free amino acids (31.5 and 31.6%), total soluble sugars (84.2 and 86.4%) and free proline content (84.2 and 86.4%) were recorded with application of DI × Se2 practice in both seasons, respectively. Under DI, Se2 recorded the maximum values of root length, shoot fresh weight and shoot dry weight in the second season. Under drought, the increases in seed yield due to application of Se1 and Se2 amounted to 1.72 and 1.62 folds in the 1st season and 1.50 and 1.43 folds in 2nd one, respectively. The most effective practice for improving IWUE was Se1× DI in both seasons, followed by Se2 × DI. Based on the chromatographical detection, the maximum values of Anethole were recorded with FI × Se2 while L-Linalool has greatly increased with DI × Se2. In conclusion, the growers in arid and semi-arid zones are advised to use selenium (2.0 mM) in anise fertilization to mitigate the adverse impacts of drought, and keeping crop yield and quality. [ABSTRACT FROM AUTHOR]