Phenolic Content, and Antioxidant and Antimicrobial Activities of Crataegus Oxyacantha L (Rosaceae) Fruit Extract from Southeast Serbia

Purpose: The aim of this work was to determine the content of total phenols, total flavonoids, anthocyanins, as well as antioxidant and antimicrobial activities of hawthorn (Crataegus oxyacantha L.) alcohol, hydroalcohol and aqueous extracts.Methods: The content of total phenols, flavonoids and anthocyanins of the alcohol, hydroalcohol and aqueous extracts of hawthorn were determined using spectrophotometric methods. Antioxidant assay was based on the measurement of DPPH absorbance at 517 nm caused by the reaction of DPPH with the test sample. Antimicrobial activity was evaluated by measuring the zone of inhibition against selected test microorganisms: Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonasaeruginosa, and Salmonella abony while antifungal activity was tested against two organisms: Aspergillus niger and Candida albicans.Results: The results of spectrophotometric investigations indicate that the content of total phenol compounds in the investigated extracts varied from 2.12 to 30.63 mg GAE g-1 of fresh hawthorn sample. The content of anthocyanins ranged from 0.3207 to 3.168 mg of cyanidin-3-O-glucoside g-1 of fresh hawthorn fruit. The fruit extracts showed high antioxidant activity with DPPH radical transformation value as high as 89.9 % in the methanol-water (50/50, v/v%)) extract. The ethanol extract exhibited antimicrobial activity against all test microorganisms except two, Bacillus subtilis and Staphylococcus aureus, and one species of fungi, Aspergillus niger. Flavonoid structure influenced the extract’s selectivity towards Gram-positive and Gram negative bacteria.Conclusion: Extracts of the fruit of Crataegus oxyacantha L. can be used as natural antioxidant and antimicrobial preparations.Keywords: Crataegus oxyacantha L.; Natural phenolic compounds; Antioxidant and antimicrobial activity, Southeast Serbia

Convoluted CC-cosine functions and semigroups. Relations with ultradistribution and hyperfunction sines

Convoluted $C$-cosine functions and semigroups in a Banach space setting extending the classes of fractionally integrated $C$-cosine functions and semigroups are systematically analyzed. Structural properties of such operator families are obtained. Relations between convoluted $C$-cosine functions and analytic convoluted $C$-semigroups, introduced and investigated in this paper are given through the convoluted version of the abstract Weierstrass formula which is also proved in the paper. Ultradistribution and hyperfunction sines are connected with analytic convoluted semigroups and ultradistribution semigroups. Several examples of operators generating convoluted cosine functions, (analytic) convoluted semigroups as well as hyperfunction and ultradistribution sines illustrate the abstract approach of the authors. As an application, it is proved that the polyharmonic operator $(-\Delta)^{2^{n}},$ $n\in {\mathbb N},$ acting on $L^{2}[0,\pi]$ with appropriate boundary conditions, generates an exponentially bounded $K_{n}$-convoluted cosine function, and consequently, an exponentially bounded analytic $K_{n+1}$-convoluted semigroup of angle $\frac{\pi}{2},$ for suitable exponentially bounded kernels $K_{n}$ and $K_{n+1}.