Characterization of Saccharomyces cerevisiae based microcarriers for encapsulation of black cumin seed oil: Stability of thymoquinone and bioactive properties.

Thymoquinone is a chief phytochemical constituent of black cumin seed oil (BCSO) and shows strong bioactivity. It has a weak stability against environmental conditions like heat and light. Encapsulation process by Saccharomyces cerevisiae is a popular technique to preserve the bioactivity and increase the stability of functional bioactive compounds. In the current study, BCSO was encapsulated by both plasmolysed (PYC) and nonplasmolysed yeast cell (NPYC) and stability of thymoquinone and bioactive properties of all samples were evaluated. And also, some physicochemical, morphological and conformational characterizations were carried out for the encapsules. The results showed that thymoquinone concentration and its bioactivity were preserved better in PYC during storage compared to BCSO and NPYC. The highest degradation ratio of thymoquinone during storage for the BCSO was 96.78% while the lowest one was for the PYC sample (52.63%).

Volatile compounds and bioactivity of Eremurus spectabilis (Ciris), a Turkish wild edible vegetable.

Eremurus spectabilis grows in the spring as a wild vegetable and for many years has been used both as a food or food additive and for therapeutic purposes. This study investigated the total phenolic content and the antimicrobial, antioxidant, and antiradical activities of methanol, ethanol, and aqueous extracts of E. spectabilis (obtained from the Antalya region of Turkey). In addition, volatile compounds of E. spectabilis were characterized by using gas chromatography/mass spectrometry. Major components of E. spectabilis volatile compounds were carvone (44.64%), carvacrol (14.45%), pentane, 2-methyl- (7.34%), (E)-caryophyllene (5.57%), valencene (5.11%), cis-calamenene (2.01%), cadalene (1.10%), and acetic acid (1.12%). The highest total phenolic content was seen with methanol extract (mean±standard deviation, 31.92 ± 0.48 mg gallic acid equivalents/g dry extract). The ethanol extract showed the highest antiradical activity, with a 50% inhibitory concentration of 35.14 µg/L in the 1,1-diphenyl-2- picrylhydrazyl assay. The strongest antioxidant activity was detected in methanol extract (81.72 ± 0.62 mg ascorbic acid equivalents/g). Twelve bacteria species were used to analyze the antimicrobial activity of extracts. The 1% concentrations of all extracts showed no inhibitive effect on any bacterium. The most resistant bacterium was Yersinia enterocolitica, and the most sensitive bacterium was Pseudomonas aeruginosa. A positive correlation was seen between concentrations and inhibition zones, and some differences occurred between antimicrobial activity of other concentrations.