Search Results (5)

This study investigates the phytochemical composition and cultivation strategies for watermelon (Citrullus lanatus (Thunb.)) in Lithuania’s temperate climate, focusing on its biological activity. Employing innovative grafting techniques and clear plastic film mulching, we successfully countered fusarium wilt while promoting growth and bioactive compound accumulation. Our analysis showed significant cultivar-dependent variations in total phenolic content (ranging from 94.34 ± 8.12 to 327.42 ± 9.14 mg GAE/kg fw in pulps and from 120.46 ± 7.52 to 364.27 ± 6.85 mg GAE/kg fw in rinds), lycopene (ranging from 1.15 ± 0.42 to 103.60 ± 1.69 mg/kg fw in pulps), sugar, and nitrate levels, revealing the influence of genetics and environment on the fruit’s phytochemical profile. Moreover, several Lithuanian watermelon cultivars exhibited comparable or superior levels of key bioactive compounds relative to imported varieties. These findings underscore the potential of watermelon rind and pulp as valuable sources of antioxidants and other bioactive phytochemicals, relevant for nutritional enhancement and medicinal applications. The results contribute to a deeper understanding of watermelon cultivation in Lithuania and highlight opportunities for optimizing agricultural practices to enhance the health benefits associated with this important fruit. Full article

Flavonols are found in plants as aglycones and as glycosides. Antioxidant activity of flavonols may occur via several mechanisms within the cell, and mitochondria as a target may play an important role. There is a lack of information about the influence of the sugar moiety on biological activity of flavonoid glycosides. The aims of study were to investigate the effects of quercetin and its glycosides on mitochondrial respiration rates at various metabolic states, and to evaluate their antioxidant potential using chemical and biological approaches. Mitochondrial function was measured using an oxygraphic method, cytochrome c reduction spectrophotometrically, H₂O₂ generation in mitochondria fluorimetrically, and antioxidant activity of flavonoids using an HPLC-post column system. Our data revealed that quercetin and its glycosides isoquercitrin, rutin, and hyperoside uncouple kidney mitochondrial respiration (increasing the State 2 respiration rate) and significantly reduce cytochrome c. Moreover, quercetin, and its glycosides decrease the production of mitochondrial H₂O₂ and possess radical scavenging and ferric reducing capacities. The highest activity was characteristic for quercetin, showing that the sugar moiety significantly diminishes its activity. In conclusion, our results show the efficient radical scavenging, ferric and cytochrome c reducing capacities, and uncoupling properties of quercetin and its glycosides, as well as the importance of the sugar residue and its structure in the regulation of kidney mitochondrial function. Full article

Successful heart-lung complex transplantation was performed in a 48-year-old man. During the postoperative period, M. tuberculosis infection was diagnosed, and the treatment subsequently started. One year after, the patient was urgently hospitalized due to myocardial infarction. However, despite the best efforts, the patient died. Antituberculosis treatment is recommended to all the patients with confirmed active tuberculosis. Treatment of tuberculosis in transplant recipients is similar to that of the general population, with the exclusion of rifamycins in the regimen and longer duration of treatment. Full article

The most important attention is paid to the search of natural antioxidants and their evaluation in medicinal and food raw materials of plant origin. A number of plants, their extracts, food products, and medicinal preparations appear to be the objects of scientific research. Effectiveness and informative character of research, undoubtedly, depend on relevance, sensitivity, and efficiency of the methods chosen. The aim of this work was to develop and validate the postcolumn high-performance liquid chromatography (HPLC)-DPPH method as well as its application in the evaluation of antioxidant activity of known and unknown compounds scavenging free radicals and existing in medicinal plant raw materials. HPLC-separated compounds were identified at the wavelength of 275 nm, and then the mobile phase with analytes flowed through a mixing tee to the reaction coil, where DPPH reagent solution was supplied. The solution flow rate was 0.4 mL/min. The reaction coil was connected with UV/VIS type detector, which measured absorption of flowing solution at the wavelength of 520 nm. It was determined that vitexin rhamnoside, the dominant compound in the leaves of Crataegus monogyna, was not a significant radical scavenger. The most active antioxidant in the leaves and flowers of Crataegus monogyna was chlorogenic acid. The most active antioxidant in Origanum vulgare raw material was rosmarinic acid. Identified analytes in the extracts of Achillea millefolium that possessed radical-scavenging properties were chlorogenic acid, luteolin-7-Oglucoside, rutin, and luteolin. Full article

Achillea millefolium L. sensu lato (yarrow) is the best-known species of the genus Achillea due to numerous medicinal applications both in folk and conventional medicine. Phenolic compounds such as flavonoids and phenol carbonic acids are present in yarrow and constitute one of the most important groups of pharmacologically active substances. In the present study, yarrow flowers gathered from native populations in different locations of Lithuania were analyzed for phenolic compound composition. High-performance liquid chromatography (HPLC) was used for chemical analyses. Eight phenolic compounds – chlorogenic acid and flavonoids, namely vicenin-2, luteolin-3',7-di-O-glucoside, luteolin-7-O-glucoside, rutin, apigenin-7-O-glucoside, luteolin, and apigenin – were identified in the extracts from yarrow flowers. Considerable variation in accumulation of phenolic compounds among the flowers from different locations was observed. The samples were divided into two main groups based on chemical composition: the first group was characterized by lower than the mean total amount of the identified phenolics; the second was formed from samples accumulating higher concentrations of investigated secondary metabolites. The total amount of the identified phenolics in yarrow flowers from different populations varied from 13.290 to 27.947 mg/g. Full article