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This study investigated different amino acid-based surfactants (AASs), also known as biosurfactants, including sodium N-dodecyl asparagine (AS), sodium N-dodecyl tryptophan (TS), and sodium N-dodecyl histidine (HS) for their potential anticorrosion, antibacterial, and antidermatophyte properties. The chemical and electrochemical techniques were employed to examine the copper corrosion inhibition efficacy in H2SO4 (1.0 M) solution at 298 K. The results indicated their promising corrosion inhibition efficiencies (% IEs), which varied with the biosurfactant structures and concentrations, and the concentrations of corrosive medium. Higher % IEs values were attributed to the surfactant adsorption on the copper surface and the production of a protective film. The adsorption was in agreement with Langmuir adsorption isotherm. The kinetics and mechanisms of copper corrosion and its inhibition by the examined AASs were illuminated. The surfactants behaved as mixed-kind inhibitors with minor anodic priority. The values of % IEs gained from weight loss technique at a 500 ppm of the tested surfactants were set to be 81, 83 and 88 for AS, HS and TS, respectively. The values of % IEs acquired from all the applied techniques were almost consistent which were increased in the order: TS > HS ≥ AS, establishing the validity of this study. These surfactants also exhibited strong broad-spectrum activities against pathogenic Gram-negative and Gram-positive bacteria and dermatophytes. HS exhibited the highest antimicrobial activity followed by TS, and AS. The sensitivity of pathogenic bacteria varied against tested AASs. Shigella dysenteriae and Trichophyton mantigrophytes were found to be the most sensitive pathogens. HS exhibited the highest antibacterial activity against Shigella dysenteriae, Bacillus cereus, E. coli, K. pneumoniae, and S. aureus through the formation of clear zones of 70, 50, 40, 39, and 35 mm diameters, respectively.AASs also exhibited strong antifungal activity against all the tested dermatophyte molds and fungi. HS caused the inhibition zones of 62, 57, 56, 48, and 36 mm diameters against Trichophyton mantigrophytes, Trichophyton rubrum, Candida albicans, Trichosporon cataneum, and Cryptococcus neoformans, respectively. AASs minimal lethal concentrations ranged between 16 to 128 µg/ml. HS presented the lowest value (16 µg/ml) against tested pathogens followed by TS (64 µg/ml), and AS (128 µg/ml). Therefore, AASs, especially HS, could serve as an effective alternative antimicrobial agent against food-borne pathogenic bacteria and skin infections-associated dermatophyte fungi. [ABSTRACT FROM AUTHOR]

Cardamom (Elettaria cardamomum) fruits or capsules are rich in bioactive phytochemicals with beneficial health impacts. Very few studies reported the chemistry and functionality of Elettaria cardamomum lipids, fixed oil, and cold pressed cardamom oil (CPCO). This work characterized CPCO for its lipid classes, fatty acids, phytosterols, tocols, total phenolics, antiradical potential (toward galvinoxyl and DPPH· radicals), antioxidative effects, and antimicrobial behavior (against foodborne bacteria and dermatophytic fungi). Neutral lipids were detected at the highest amount (ca. 96.6%), followed by glycolipids (ca. 2%) and phospholipids (ca. 1.3%). Oleic (C18:1, 43.7%), palmitic (C16:0, 21.6%), and linoleic (C18:2, 17.6%) were the major fatty acids in CPCO. The levels of monounsaturated fatty acids (MUFA), saturated fatty acids (SFA), and polyunsaturated fatty acids (PUFA) were 47%, 32%, and 21%, respectively. CPCO contained large amounts of unsaponifiables (16.4 g/kg). The total content of phytosterols was 222 mg/100 g oil, wherein β-sitosterol was the main compound, followed by sitostanol, campesterol, stigmasterol, Δ5-avenasterol, and citrostadienol. The total content of tocols was 2.38 mg/100 g of oil, and the contents (mg/100 g oil) of α-, β-, γ-, and δ-tocopherols in CPCO were 1.25, 0.08, 0.58, and 0.28, respectively. Besides, CPCO contained high amounts of total phenolics (3.9 mg GAE/g oil). CPCO exhibited better antiradical traits than extra virgin olive oil. The induction time (IT) recorded for sunflower oil (SFO) and CPCO blend (9:1, v/v) was 405 min, while the IT for blend) 8:2, v/v) was 532 min. Besides, CPCO showed broad antimicrobial effects against foodborne pathogens (Salmonella enteritidis, Staphylococcus aureus, Listeria monocytogenes, and Escherichia coli) and dermatophytic fungi (Trichophyton mentagrophytes and Trichophyton rubrum). It could be concluded that CPCO is a good source of lipid-soluble bioactives, making it a unique raw material for novel food, cosmetic, and pharmaceutical products. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate cold-pressed rosemary oil (RO) for its lipid classes, subclasses, fatty acid composition, tocochromanols and total phenolics amount. Antiradical activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH•) and galvinoxyl radicals, antioxidant activity, as measured by the Rancimat test, as well as antimicrobial activity against food-borne bacteria, and dermatophytic fungi of RO were evaluated. In RO, the amount of neutral lipids was highest (ca. 86%), followed by phospholipids (0.92%) and glycolipids (0.88%). The percentages of monounsaturated, polyunsaturated, and saturated fatty acids were 41.7, 42.3, and 15.8%, respectively. Linoleic acid (41.7%) and oleic acid (41.2%) were the major fatty acids while linolenic acid accounted for 1.3% of total fatty acids. The following tocochromanols were detected: α-, β-, γ- and δ-tocopherols, which accounted for 291, 22, 1145, and 41 mg/100 g oil, respectively, as well as α-, β-, γ- and δ-tocotrienols, which accounted for 18, 12, 29, and 158 mg/100 g oil, respectively. RO also contained high levels of phenolic compounds (7.2 mg GAE/g). After 60 min of reaction with free radicals, 67% of DPPH• and 55% of galvinoxyl radicals were quenched by RO. Rancimat test showed that blending RO with sunflower oil increased the induction period (IP) for blends. The IP of the RO: sunflower oil blend (1:9, v/v) was 390 min, and RO: sunflower oil blend (2:8, v/v) was longer (540 min). RO exhibited high antimicrobial potential against food-borne pathogenic bacteria (E. coli, S. enteritidis, and L. monocytogenes) and high antifungal potential against dermatophyte fungi (T. mentagrophytes, and T. rubrum). RO had unique high level of γ-tocopherol, which is a scavenger of reactive nitrogen species making it a promising material in the food, cosmetic and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

In this study, three Egyptian bee pollen types from different plant sources, namely maize ( Zea mays), clover ( Trifolium alexandrinum), and date palm ( Phoenix dactylifera), were evaluated as natural antimicrobial agents, antioxidants, and food additives. A methanolic extract of maize bee pollen exhibited the highest antibacterial activity, followed by clover and date palm bee pollen. Staphylococcus aureus and Escherichia coli were the most sensitive, followed by Listeria monocytogenes, Salmonella enteritidis, and Pseudomonas aeruginosa. In ghee, all methanolic extracts, especially that of maize bee pollen, showed high antioxidant activities as radical scavenger substances and as inhibitors of lipid peroxidation. Sensory evaluation of yoghurt supplemented with different bee pollens revealed that maize bee pollen improve texture, increased gel strength, and decreased syneresis and had favorable nutty flavor, while clover and date palm pollen added a sweet taste and bean-like flavor, respectively. These findings establish the potential of Egyptian maize and clover bee pollen as antioxidants, antimicrobial agents, promising natural food supplements, and natural preservatives. [ABSTRACT FROM AUTHOR]

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper. [ABSTRACT FROM AUTHOR]