Evaluation of Fruit Extracts Influence on the Susceptibility of Escherichia Coli Rods to the Bactericidal Action of Human Serum

This study determined the influence of the methanol (ME) and water (WE) fruit extracts obtained from eight species of Rosaceae and Grossulariacae family on the susceptibility of Escherichia coli rods to the lytic action of normal human serum (NHS). Bacteria were incubated for 24 h in tryptic soy broth with varying concentrations (1, 5, 10, 20, 30, 40, and 50 mg ml-1) of raspberry, cherry, hawthorn, dog rose, gooseberry, chokeberry, quince, and Japanese quince extracts and then the bactericidal activity of NHS was established. We found that the resistance of E. coli rods to the bactericidal action of serum was altered by prior incubation with all tested extracts and was dependent on plant extract concentration. Among the tested extracts, gooseberry (both ME and WE), raspberry ME and cherry WE were responsible for the most profound changes in serum resistance of E. coli rods. Evaluation of the antimicrobial mechanisms of action of phenolics-rich plant extracts has the potential to impact the development of novel compounds with promising applications in food and biopharmaceutical industry or medical approaches to preventing and treating pathogenic infections.

Rapid characterization of hypanthium and seed in wild and cultivated rosehip: application of Raman microscopy combined with multivariate analysis

Rosehip (pseudo-fruit) of dog rose ( Rosa canina L.) is highly valued, and owing to nutritional and sensory properties it has a significant place in the food industry. This work represents an innovative report focusing on the evaluation of the phytochemical composition of rosehips (hypanthium and seed) grown in different locations in Serbia, using Raman microspectroscopy combined with multivariate data analysis. Some significant differences arose between the analysed rosehip samples with regard to the chemical profile of both hypanthium parenchyma cells and seed, although no evident discrimination was recorded between the samples of wild and cultivated rosehip. The differences between the hypanthium samples compared were mainly determined by the content of carotenoids, phenolic compounds and polysaccharides, whereas phenolics, polysaccharides (pectin, cellulose and hemicellulose) and lipids (to a lower extent) contributed to the seed sample discrimination. The differences observed between the rosehip samples may be attributed to abiotic factors (growing, ripening and storage conditions), which had a significant impact on the carotenoid and polyphenols biosynthesis.

Variability in pomological traits of dog rose (Rosa canina L.) under the ecological conditions of the Republic of Croatia

Wild or dog rose (Rosa canina L.) is a successful colonizer of various habitats and different soil types and is widely distributed across the Republic of Croatia. In this research, in order to estimate pomological variability in native dog rose populations, four genotypes from four locations in different geographic areas of Croatia were selected and sampled. The genotypes selected were: genotype G1, originating from the continental part of Croatia (Pitomača); genotypes G2 and G3, originating from the Mediterranean part of Croatia (Kukurini and Posedarje, respectively); and genotype G4, originating from the upland part of Croatia (Gračac). Fruits were harvested at optimum harvest dates in 2010 and 2012. Genotype had a significant effect on each studied pomological trait (length, width, geometric mean diameter, sphericity, volume, surface, shape index, weight, flesh weight, flesh ratio and total dry matter content), while year significantly affected all parameters except sphericity and shape index. The highest values for most pomological traits in 2010 and 2012 were found in the G4 and G3 genotypes, respectively. This research highlighted the existence of high variability in pomological traits among dog rose populations in Croatia, which emphasizes the possibility of further breeding and cultivation.

Optimizing the micropropagation protocol for Rosa canina L. elite genotype propagation in the Belgrade area

Rosa canina L. (dog rose) is an important ornamental, edible and medicinal plant. It has been used as a rootstock for ornamental roses, grown in plantations for fruit harvesting and it is suitable for revegetation of abandoned mine lands. The propagation of native genotypes that are well adapted to local conditions can provide planting material for both revegetation and plantation purpose. Micropropagation is the most suitable method for a rapid vegatative propagation of selected wild genotypes, but an increased presence of pathogens as well as higher contamination rate during culture establishment were expected. An occurrence of a specific Fe-chlorosis during in vitro propagation of roses is also possible. Therefore, the optimal period and disinfection protocol for establishing sterile in vitro culture of selected genotypes of dog rose was investigated, as well as an effect of increasing the FeEDTA concentration in the MS medium during multiplication phase. The obtained results showed that the optimal time for taking initial explants corresponds to optimal time for taking green cuttings in traditional vegetative propagation by softwood cuttings, and the best results were achieved using shoots collected in the first week of May, when the flowers were open. The iron chelate concentration in the medium affected the mean number of shoots, and doubling of its concentration resulted in a considerably higher number of shoots per explant.

INVESTIGATION OF THE MOISTURE BINDING FORMS IN PLANT RAW MATERIALS AND THERMAL CHARACTERISTICS DETERMINATION

In this article, the forms of moisture connection and the thermal characteristics of plant materials are studied. Rosehip and hawthorn fruits were chosen as the object of research. In the heat analyzer, a decrease in the mass of the product and an increase in temperature were found when the temperature was controlled in a certain gas environment. The curves of the dependence of the dog rose and hawthorn samples on the mass and temperature are given. DTA-1/10 galvanometer sensitivity; sensitivity of the DTG-1/5 galvanometer; the maximum heating temperature is 300° С and the rate of change of the furnace heating temperature is 3° С / min. The temperature features of the process of thermolysis of plant products have been studied. As a result of the study, the initial temperature, the highest and the final temperature of endothermic action were determined. The thermophysical properties of rose hips and hawthorn fruits were studied on the basis of experiments and the results are reflected in the tables below. Coefficients of thermal conductivity and specific heat of mass in the temperature range 20-80 ºC are given.

Phenolic Composition and Biological Properties of Wild and Commercial Dog Rose Fruits and Leaves

Rosa canina L. (dog rose) is a rich source of phenolic compounds that offer great hope for the prevention of chronic human diseases. Herein, wild and commercial samples of dog rose were chemically characterized with respect to their phenolic composition by liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI/MS). Furthermore, in vitro antioxidant properties and antibacterial activity of dog rose fruits and leaves hydromethanolic extracts and infusions were also evaluated. The results revealed that wild and commercial fruits of dog rose are similar in terms of l(+)-ascorbic acid, total phenolics (TPC), total flavonoids (TFC) and total phenolic acids (TPAC) content, individual phenolic constituents and antioxidant activity. Moreover, the fruits had lower levels of phenolic compounds and also revealed lower biological activity than the leaves. On the other hands, the highest content of TPC, TFC, TPAC, individual phenolic constituents, DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity and FRAP (ferric reducing antioxidant power) were found in the leaf’s infusions. They were also the only ones to show antibacterial activity. Overall, these finding confirmed usefulness of R. canina L. leaves and fruits as a rich source of bioactive phenolic compounds with potential use in food, pharmaceutical, and cosmetic industries.

Composition and structure of regrowth forests on abandoned agricultural land

Overgrowing of agricultural land by forest in Russia is a large-scale process. This study aims to examine the composition and structure of forests that took over abandoned agricultural lands in Belorechensky district, Krasnodar Krai (Russia). The research on 4 farmland plots was carried out in 2018. At the time of observation agricultural land has been abandoned for 7 to 8 years. Research methodology was developed to determine parameters such as tree and shrub density per ha, height and age at 50 m and up to 100 m from the forest. Two study sites were dominated by mesophytes, whilst the other two sites were invaded by xerophytes. Xerophytic landscapes were co-dominated by downy oaks and dog roses. The stand density of examined plants was 1.7 times lower at 51 to 100 m than near the forest (P ≤ 0.05). There were 3.3 times as many dog roses as downy oaks. The stand density of common ash stand at 51 to 100 m from the forest edge was 10 times lower than that of dog rose (P ≤ 0.01). Mesophytic landscapes were co-dominated by black poplars and crack willows. Black poplar was 4.3 times more frequent than dog rose (P ≤ 0.002) and 130 times more common than elm (P ≤ 0.0001). Natural overgrowth or succession can affect vast areas of land. It was established that dog roses and downy oaks regenerate xerophytic fields within 6 to 7 years, whereas mesophytic fields become dominated by black poplars and crack willows within 5 to 7 years.