The differences in the chemical composition of the phenolic compounds of Salvia officinalis versus Salvia sclarea growing in different habitats, were studied. First, the optimal solvent - methanol - for ultrasonic extraction of phenolic compounds from these plants was chosen experimentally. Total phenolic content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were determined spectrophotometrically. Total phenolic content was in the range of 63.9 to 134.4 mg GAE/g of plant depending on the studied species. The highest antiradical activity was displayed by the methanol fractions of S. sclarea varieties (83 and 67%). HPLC-DAD analysis of extracts was done in order to identify the presence of individual phenolic compounds. This was done by comparison of their retention times with those observed for 17 commercially available standard compounds. The results showed differences in the phenolics composition, with plants collected on Crimean peninsula accumulating more phenolic acids than Polish varieties. In turn, the Polish varieties of sage contain bigger amount of flavonoids in their tissues.
Spośród produktów pszczelich największym uznaniem konsumentów cieszą się miody. Pszczelarze polscy słyną z produkcji miodów o wysokich walorach smakowych, odżywczych i terapeutycznych. Niestety zdarza się coraz więcej przypadków fałszowania miodów i dlatego konieczne jest poszukiwanie nowych metod pomocnych w badaniu ich jakości.
EN
Among bee products, the honey is one most appreciated by consumers. Polish bee-keepers are famous for production of honey with great taste and good nutritious and therapeutic qualities. Unfortunately, there are more and more cases of honey adulteration and therefore, it is necessary to seek new methods that could be used in testing their quality.
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Ergosterol (prowitamina D) jest jednym z głównych składników błon komórkowych grzybów. Ma on obiecujące właściwości immunostymulujące i przeciwrakowe. Muchomor czerwony stanowi bogate źródło ergosterolu, który po ekstrakcji n-heksanem lub octanem etylu łatwo jest otrzymać w formie krystalicznej.
EN
Fly agaric was extd. with n-hexane or EtOH optionally under microwave aid to recover ergosta-5,7,22-trien-3βol and other steroids. The highest yield was achieved by extn. of the gills, EtOAc was more efficient than n-hexane as a solvent.
Honey is a natural food product reach in variety of chemical compounds, which are responsible for its quality and aroma. Unifloral honeys are especially attractive for buyers and are quite frequently falsified. Thus, the assessment of their quality is indispensable. Today it relays on identification of the pollen and determination of honey physicochemical properties. In this paper the new methods for the assessment of honey quality are described. They relay on analysis and identification of volatile compounds typical for certain uniflolar honeys. These compounds are called markers. These could virtually all natural products with products of decomposition of phenylalanine, terpenes, flavonoids, aromatic acids, heterocycles, caretonoids and non-typical sugars. The second approach is to study metabolome of these honeys. The most effective metabolomic studies relay on building up “finger-prints” of certain honey branch basing on relative concentrations of chosen set of volatile compounds.
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Allelopathy has been defined by the International Allelopathy Society as "any process involving secondary metabolites produced by plants, microorganisms, viruses and fungi that influence the growth and development of agricultural and biological systems, including positive and negative effects [1]". Allelochemicals can be released into the environment and despite what effect they evoke towards living organisms this kind of specific chemical interactions is known as "allelopathy". Allelopathic phenomena have been observed and studied from ancient times. Theophrastus from Eresos, a disciple of Aristotle, reported an inhibitory effect of pigweed Polygonum spp. on alfalfa in ca. 350 B.C., whereas Pliny described the harmful effects of several plants on cropland in ca. 1 A.D. [2-5]. Although chemical interactions between plants have been known for thousands years, the term allelopathy was used for the first time in 1937 [5]. It derives from Latin words allelon ("of each other") and pathos ("to suffer") and refers to the chemical interactions among species. In recent years there has been an increasing interest towards the perspective of exploiting allelopathy and allelochemicals as an alternative strategy for controlling weeds in particular, but also for controlling insects and plant diseases. Plants produce a wide variety of secondary metabolites that play important roles in ecological interactions. This is one, probably the most pronounced, of a variety of ways in which certain plants can protect themselves against competition, infection or feeding in their natural habitats. Some of secondary metabolites may also play an important role in chemical mediation of growth and development of plant communities. These substances are called "allelochemicals" and are relea-sed into the environment in order to interfere with the growth of competing plants or act as chemical defence against pathogens and animals. Therefore such compounds might be considered as constituents of plant defence system and could be treated as a kind of chemical weapons. Originally, compounds like allelochemicals were thought to occur exclusively in higher plants. Ongoing research, however, has revealed them also to be synthesized by bacteria, lower plants and fungi. Allelochemicals may furnish an entirely new generation of naturally produced weed-controlling compounds, replacing synthetic herbicides and other pesticides with non-acumulatting easy-degradable substances.
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Zaprezentowano rośliny marchwi jako źródło substancji wykazujących aktywność allelopatyczną. Przedstawiono sposoby efektywnej izolacji poszczególnych allelozwiązków z nasion marchwi oraz zakres ich aktywności biologicznej. Rezultaty badań wskazują na to, że zarówno olejek eteryczny jak i wodny ekstrakt z nasion marchwi wykazują silną, aczkolwiek odmienną aktywność allelopatyczną warunkowaną obecnością specyficznych substancji wykazujących różną aktywność biologiczną.
EN
The possibility of use of carrot plants (Daucus carota L.) as a source of allelochemicals and define carrot’s involvement in many allelopathic interactions is presented and discussed. From literature, as well as from our experience is seen that large varieties of compounds synthesized in carrot tissues are known also for their allelopathic activity. Thus, we have found strong and variable allelopathic potency of carrot seeds presenting by essential oil and its specific components as well as the water extract and its constituents.
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