The growth rate of three rosemary clones, `Harmat', 'Salem' and `Horvát', their essential oil content and its components as well as the total phenol content and total antioxidant capacity in their aqueous and ethanolic extracts were compaired. Total phenol content (determined by Folin-Ciocalteau reagent) and antioxidant power (FRAP-value) of a...queous and ethanolic rosemary extracts were measured by spectrophotometric method. The essential oil content was determined from drug by water-steam distillation. `Harmat' showed the most intensive growth through the vegetation period. The total antioxidant power of the ethanolic extracts from all the three clones was similar: a decrease was observed at the end of the season. In most cases more antioxidant compounds were dissolved in the aqueous extracts. The total quantity of phenolic compounds shows a good correlation with the potential extent of stress effects. The difference among the phenol contents of the various clones can be derived from the difference in their tolerance, because phenols have antioxidant effects contributing to protection against harmful impacts. Difference between the two extraction methods (aqueous and ethanolic) is due to the distinct solubility of compounds. Some other components, like essential oil compounds also possess antioxidant effect and in this way they may influence the antioxidant power of extracts.
The aims of this study were on the one hand to compare of examined compounds according to their importance in nutrition and human-health, and on the other hand we made preexperiments to investigate the relationships among antioxidant capacity and the endogenous substances which contribute the antioxidant status of the plants. The following spec...ies were involved in the experiment: raspberry, blackberry, black currant, elderberry and sour cherry. These fruits have potent health-promoting antioxidant power. Glucose, fructose, total phenol, formaldehyde and anthocyanin contents were determined in addition to ferric reducing ability. Our results reflected considerable differences in the measured parameters of the analysed species. In blackberries and elderberries the high antioxidant capacity is coupled with low carbohydrate content. Besides the formerly proven correlations between total phenol content, anthocyanin concentration and antioxidant capacity, these parameters also correlated with the measured formaldehyde concentrations, hereby we can follow the methylation /demethylation status of the plant.
The aim of our preliminary studies was to characterize the change in the activity of enzymes PPO and PDX, the concentration of total soluble phenolic compounds and soluble protein content of different tobacco cultivars measured in tobacco plants during cultivation. The results suggest that a shorter cultivation period (13-14 weeks) is...more favourable for tobacco plants as protein source than for tobacco industrial use (16-17 weeks). We found some correlation between the concentration of total soluble phenolic compounds and PPO activity data. In the increasing and maximum period of total phenol content the PPO activity was high. But later because of decrease of substrate phenol content the activity of PPO also decreased. We found higher soluble protein concentrations in Virginia than in Burley varieties.
This report forms a part in our long-term study dedicated to reveal the antioxidant properties of apricot fruits through several years. Nineteen apricot cultivars and 8 hybrids were comparatively analysed. Total phenol content and antioxidant activity showed a good correlation. The tested cultivars and hybrids could be arranged in three groups...representing different antioxidant activities, 12 entries were involved in the group with relatively low antioxidant capacity (FRAP value < 1500 mmol/L); 10 accessions were classified in the group with medium antioxidant capacity (1500 mmol/L < FRAP value < 3000 mmol/L); and 5 genotypes were grouped to the category of high antioxidant value (FRAP > 3000 mmol/L). `Morden 604' produced a surpassingly outstanding antioxidant character. H-donating ability has further supported our results. Phenolic substances were accumulated and ferric reducing ability was increased in the ripe fruits compared to the unripe ones. High levels of variations in the total phenol content and antioxidant capacity in of apricot fruits were revealed in this study. Environment, year or rootstocks may also influence the antioxidant properties of fruits. however it seems to be convincing that crossing parents with outstanding antioxidant character can produce hybrids with higher antioxidant capacity. Hungarian apricots are widely appreciated for their premium flavour and — as it was evidenced in this study — for their relatively good antioxidant properties. However, delicious fruits should be made functional foods having beneficial health effects through accumulating large amounts of antioxidant molecules in the fruit flesh.
The aim of this study was to investigate the postharvest effect of methyl jasmonic acid (MJ) and hot water on internal break-down and quality loss of apricot fruit under shelf life conditions. Cultivar Flavor cot apricot fruit were used to treat with water as control treatment, with 0.2 mmol/L MJ and with hot water 35 oC for 5 min. F...ruit were stored at room temperature and were examined every 2 days for internal break-down and quality loss. Results showed that treated fruits with MJ and hot water showed the lowest weight loss and the highest firmness during all assessment times. Control fruits showed losing of customer acceptance from the day 2 of shelf life and then decreased dramatically to approximately loss all the acceptance at day 8. The SSC showed sever reduction in untreated fruit after day 6 at shelf life. Total phenol content reduced and polyphenol oxidase (PPO) increased in all assessment times for all treatments. Meanwhile MJ showed the best values for phenol content and lowest PPO activity. The results supported the idea of using some elicitors like methyl jasmonic and hot water treatments to enhance shelf life of apricot fruit.
The aim of our experiments was to investigate the internal quality parameters of some old melon and watermelon landraces or varieties whether they have any desirable characteristics. Measurements were carried out using 8 different types of melon (Cucumis melo L.) and 8 accessions of watermelon (Citrullus lanatus...em>[Thumb]), which were self pollinated under greenhouse conditions. Besides the determination of dry matter content; soluble solids, titratable acidity of the fruit juices, investigation of carbohydrates, total phenol content was measured by spectrophotometer. Total antioxidant capacities were determined spectrophotometrically using the FRAP method. We found some accesions both among melon and watermelon varieties, which could be characterized by outstanding inner content.
Several parameters influencing the antioxidant capacity were measured in our experiments to compare strawberry and raspberry cultivars. The analysed cultivars were: 'Honeoye', 'Elsanta', 'Onebor (strawberries) and 'Glen Ample', Fertődi zamatos', 'Mailing Expoit' (raspberries). Besides the determination of dry matter content the content of gluc...ose, fructose, total phenol and anthocyanine, the reducing power, H-donating activity and total scavenger capacity were measured as well as the compound of mineral nutrients. Among the species and the cultivars, differences were obtained. These results call the attention to the features of cultivars and to count on the antioxidant-capacity describing values in case of consuming these fruits. In early spring and summer the consumption of strawberry and raspberry has a beneficial contribution to the antioxidant status of our body. In this respect these are more valuable than the year-long consumable apple. Accordingly, our measurements showed higher amount of sucrose, phenolic compounds and anthocyanine in raspberries, but strawberries contained more glucose and fructose and had stronger H-donating activity. It is worth to keep in mind that e.g. which cultivar contains more of certain compounds because of the strictly determined allowable dose in some diseases (e.g. diabetes).
Among vegetables produced both for raw consumption and processing, tomato is one of the most important one in Europe, by production area and by yield as well. In the past years several study dealt with the investigation of the inner content of tomato, with special regards to antioxidant content. In this paper cherry tomato varieties and landrac...es from conventional and organic production were compared. Besides basic investigations sensory analysis were designed and Antioxidant Capacity (AOC) and Total Phenol Content (TPC) were measured. The aim of the research was to compare varieties and to study the effect of variety and production methods on antioxidant capacity and sensory profiles.
Oxygen free radicals play an important role in the development of different disorders like inflammatory-immune injury, carcinogenesis, hepatic toxicity and artherosclerosis. The antioxydant role of a wide spectrum of natural products has been established. Flavonoids and other phenolic compounds (proanthocyanidins, rosmarinic acid, hydroxicinnam...ic derivatives, catechines, etc.) of plant origin have been reported as scavengers and inhibitors of lipid peroxidation.
We have studied the antioxidant activity as well as content and composition of natural phenolics in a series of medicinal plants with phytotherapeutical significance. Thus we determined the total phenol contents and studied the composition of flavonoids, polyphenols, phenolic acids of different vegetative and reproductive organs of medicinal plants: Anthriscus cerefolium (L.) Hoffm., Petroselinum crispum L., Cichorium intybus L., Helichrysum arenarium D.C.„cempervivum tectorum L., Taravacum officinale Web.
Characteristic constituents in the various crude drugs were determined by chromatographic (TLC, HPLC) and spectroscopic (UV, UV-VIS) methods. The non specific scavenger activities of the medicinal plant extracts were studied by the chemiluminometric technique. The changes of chemiluminescence intensity of the H,G,•0H-luminol system at increasing concentrations of the H702/ -OH were measured. Inhibitory effects of selected standardized fractions from plants were tested on ascorbic acid induced lipid peroxidation in rat liver and homogenates.
The best correlation were established with total phenolics in some medicinal plants (S. tectorum, T. officinale) while activities in other cases seem to be influenced by flavonoids (P. crispum, H. arenarium, A. cerefolium) and by hydroxicinnamic derivatives (C. intybus).