Bojana Miladinović

Comparison of the Hypotensive and Bradycardic Activity of Ginkgo, Garlic, and Onion Extracts

The acute effect of ethanol extracts ginkgo (Ginkgo biloba L.), garlic (Allium sativum L.), and onion (Allium cepa L.) on arterial blood pressure (BP), and heart rate (HR) in anesthetized normotensive rats was examined and compared. Arterial BP was registered in the left carotid artery. The data showed that intravenous administration of the extracts produced dose-dependent and reversible hypotensive and bradycardic effects. The most effective in reducing arterial BP and HR is extract of garlic. There were statistically significant differences in bradycardic and hypotensive effects of the garlic and ginkgo extracts.

Chemical profile and antioxidative and antimicrobial activity of juices and extracts of 4 black currants varieties (Ribes nigrum L.).

UNLABELLED The aim of this article was to determine the chemical composition (anthocyanin and ascorbic acid contents, total phenols, and tannins), and the antioxidative, and antimicrobial activities of the juices and methanol extracts of 4 varieties-Tenah, Triton, Ben Sarek, and Ometa. The juices were made during 2008, 2009, and 2010 from the berries grown on the same location. Statistically significant differences were found in all the tested parameters of each variety for every year. Ometa variety exhibited the best antioxidative activity. The highest ascorbic acid value had Tenah juice from 2010 (211 mg/100 g) and Ben Sarek methanol extract (656 mg/100 g). Delphinidin-3-ruthenoside was the dominant anthocyanin in Triton, Tenah, and Ben Sarek variety during all 3 y and Ometa in 2010 where Ometa in 2008 and 2009 had slightly higher content of cyanidin-3-ruthenoside. The minimum inhibitory and microbicidal concentrations ranged from MIC/MBC(MFC) = 62.5 to 500 mg/mL for juices and 0.4 to 500 mg/mL for extracts. There was no significant difference in the effect of the juices against Gram(+) and Gram(-) bacteria. All the extracts acted in lower concentrations than juices. PRACTICAL APPLICATION Data contained in this article provide an insight into the effects the weather condition has on the content of the bioactive compounds in genetically different types of black currants, during the 3-y observation period. This article is relevant to the commercial application of black currants-based dietary supplements.

Effects of Extracts of Ginkgo, Onion, and Celery on the Contractility of Isolated Rat Atria

The acute negative inotropic and chronotropic effects of the commercial extract of ginkgo leaf (Gingium®) and ethanolic extracts of onion bulbs and celery root on spontaneous and noradrenalin-stimulated contractions of the Wistar rat atria were investigated. All analyzed extracts exerted negative inotropic effects on the isolated rat atria. Among the tested extracts, the extract of ginkgo showed the strongest negative inotropic effects on rat atria, either in spontaneous or noradrenalin-induced contractions, being more potent than the onion and celery extracts, respectively.

Inhibitory effect of aqueous and ethanolic garlic (Allium sativum L., Lilliaceae) extracts on the rat atria.

The acute negative inotropic and chronotrophic effects of aqueous and alcoholic garlic extracts (Allium sativum L.) on spontaneous and adrenalin-stimulated contractions of the Wistar rat atria were investigated. The addition of garlic extracts to isolated rat atria evoked negative inotropic and chronotropic effects. Ethanolic garlic extract exerts much stronger negative inotropic (58.33 ± 14.76%) effects than aqueous extract (43.66 ± 16.32%). The difference in frequency reduction is especially conspicuous. Aqueous garlic extract very slightly affects the frequency, while ethanolic extract reduces it by more than 40%. In addition to these effects, the positive inotropism and chronotropism induced by the addition of noradrenaline, were much more antagonized by ethanolic garlic extract than by aqueous extract. Moreover, ethanolic garlic extract establishes sinus rhythm in the atria with extrasystoles induced by noradrenaline.

Antispasmodic Effect of Black Currant (Ribes nigrum L.) Juice and its Potential Use as Functional Food in Gastrointestinal Disorders

Objective: The purpose of this study was to investigate the relaxative effects of blackcurrant juice on the gastrointestinal smooth muscle in vitro. Materials and Methods: Berries of the blackcurrant cultivar Ometa were used for the preparation of the juice used. The spasmolytic activity of blackcurrant juice was tested on rat ileum isolated from male Wistar rats by monitoring its influence on spontaneous contractions, as well as contractions induced by potassium chloride (KCl), barium chloride (BaCl2), calcium chloride (CaCl2), and acetylcholine (Ach). The results are expressed as the mean ± standard deviation obtained in 6 measurements and statistical significance was determined by the Student t test, with p < 0.05 taken as significant. Results: The blackcurrant cultivar Ometa significantly reduced the frequency and the amplitude of spontaneous contractions (57.94 ± 3.44%) and Ach-induced contractions (42.74 ± 5.36%; p < 0.05) of the isolated rat ileum. Cumulative concentrations (0.01–3 mg/mL) of the Ometa juice also reduced contractions of the isolated rat ileum stimulated by KCl (51.46 ± 6.87%), CaCl2 (57.54 ± 6.47%), and BaCl2 (58.54 ± 10.55%). The inhibitory effects of the juice were proportional to the applied concentration. Conclusion: The antispasmodic effect of Ometa cultivar shows that common gastrointestinal disorders could be treated by the functional food.