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EN
The article presents research on the exploring of extraction process of biologically active substances from the leaves of the Moringa oleifera tree using ethanol. Ethanolic extracts were obtained using three different techniques: maceration with shaking, ultrasound-assisted extraction and extraction in Soxhlet apparatus, in different time variants: 1, 2 and 4-hours. After solvent evaporating and drying, the yields of dry extracts obtained in particular processes were calculated. The antioxidant activity of extracts was analyzed spectrophotometrically using DPPH radical scavenging method, and total phenolic content (TPC) was determined by Folin-Ciocalteu method. By means of gas chromatography with mass selective detector (GC-MS), 11 biologically active compounds present in ethanolic extracts were identified, among which α-tocopherol had the greatest share. Based on the results, the influence of the extraction technique and time on the yield and antioxidant activity of M. oleifera leaf extracts were discussed.
EN
Moss cushion plays an important role in recruitment of vascular plants. In this study, we examined the effects of water soluble extracts (WSE) of Abietinella abietina on germination of Qinghai spruce (Picea crassifolia) and the effects of moss substrates (A. abietina) on seedling emergence of P. crassifolia in two greenhouse experiments. We found that the WSE of moss affected germination of P. crassifolia in two ways: (1) the WSE reducing the risk of fungal infection to the seeds, improve the germination rate; and (2) the WSE affects germination by its concentration, that is, low concentrations of WSE (i.e., 0.5 mg ml-1 and 5 mg ml-1) stimulate, while high concentrations (i.e., 50 mg ml-1) inhibit it. In seedling emergence experiments, we detected that the moss substrates (both thick and thin mosses) facilitate the emergence of P. crassifolia in dry and intermediate moisture conditions, but inhibit it in moist conditions. In bare soil, the P. crassifolia emergence was also controlled by moisture conditions; the highest (60%) and the lowest (35%) emergence occurred in the moist conditions and dry conditions, respectively. We also found that P. crassifolia seedlings were thinner and taller, but their number higher in moss cushion than in bare soil. Thus we conclude that there is nurse effect of A. abietina cushion on recruitment of P. crassifolia in both dry and intermediate moisture conditions.
EN
High-performance liquid chromatography (HPLC) and ultraviolet (UV) spectrophotometric methods were developed for analysis of berberine, the principal bioactive constituent, in Coscinium fenestratum extracts. The HPLC and UV spectrophotometric determinations were performed at 226, 270, and 340 nm. The methods were validated by assessing linearity, sensitivity, precision, and accuracy. HPLC detection was found to be more effective than spectrophotometric determinations. The content of berberine determined by HPLC method at detection wavelengths of 270 and 340 nm was found to be higher as compared to the value obtained at wavelength of 226 nm. The content of berberine determined by HPLC ranged from 0.98 to 0.99 (%w/w) in the methanol extract, 0.85 to 0.88 (%w/w) in the methanol-water (1:1) extract, and 0.24 to 0.25 in the water extract.
EN
Harmaline and harmine accounted for more than 70% in composition in extracts of P. harmala. More attention, however, should be paid to the other alkaloids which would be favorable or unfavorable to the efficacy and safety of the products. It was necessary to determine these trace alkaloids in the extracts; thereafter, most of them have been characterized. Diglycoside vasicine, vasicine, vasicinone, harmalol, harmol, tetrahydroharmine, 8-hydroxy-harmine, ruine, harmaline, and harmine were separated and identified with reference substances and characteristic MS spectra in extracts by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and high-performance liquid chromatography (HPLC). Three trace alkaloids, vasicine, harmalol, and harmol were determined using the developed chromatographic separation method subsequently. The average contents of vasicine, harmalol, and harmol in extracts of ten batches were 2.53 ± 0.73, 0.54 ± 0.19, and 0.077 ± 0.03%, respectively. The total content of the three alkaloids was 3.23 ± 0.90% (from 1.81 to 4.48%). For rough estimation of all the relative alkaloids except of harmaline and harmine, the average total areas of all peaks in extracts varied from 4.35 to 26.64% detected at 220, 254, 265, 280, and 380 nm, respectively. The results indicated that area normalization method was powerless for the quality evaluation for traditional herb medicine consisting of numerous compounds with highly differential features. It might be concluded that LC-MS or HPLC could be utilized as a qualitative and quantitative analytical method for quality control of the extracts from seeds of P. harmala L.
PL
Badania dotyczyły wyosobnienia grzybów zasiedlających nasiona bobu oraz oceny wpływu wodnych wyciągów z kolendry siewnej i kopru włoskiego na rozrost liniowy grzybów fitopatogennych: Fusarium culmorum, Fusarium oxysporum, Fusarium avenaceum, Fusarium sambucinum i Ulocladium consoriale. Nasiona bobu w 47,75% zasiedlały patogeniczne gatunki grzybów, które reprezentowane były głownie przez: rodzaj Fusarium oraz Ulocladium consoriale i Helminthosporium solani. 52,25% w ogólnej populacji mikroflory nasion bobu stanowiły saprofity z dominacją Penicillium spp., Cladosporium herbarum oraz Alternaria alternata. W warunkach in vitro wodne wyciągi z kopru włoskiego i kolendry siewnej niezależnie od zastosowanego stężenia stymulują wzrost liniowy kolonii grzybów: F. avenaceum, F. sambucinum, F. oxysporum. Fungistatyczne oddziaływanie testowanych wyciągów zaznaczyło się jedynie w odniesieniu do F. culmorum. Wodny wyciąg z kolendry siewnej zahamował rozrost powierzchniowy tego grzyba w 61-81%, a z kopru włoskiego w 40-79%.
EN
The research concerned the isolation of the fungi growing in broad bean seeds and the evaluation of the influence of aqueous extracts from coriander and fennel on linear proliferation of pathogenic fungi: Fusarium culmorum, Fusarium oxysporum, Fusarium avenaceum, Fusarium sambucinum and Ulocladium consoriale. Broad bean seeds are colonized in 47,75% by pathogenic fungi species, which are mainly represented by: genus Fusarium, Ulocladium consoriale and Helminthosporium solani. 52,25% in the broad bean seeds' micoflora overall population is represented by saprophytes with the dominance of Penicillium genera, Cladosporium herbarum and Alternaria alternata. In the in vitro conditions aqueous extracts from fennel and coriander, regardless of the concentration used, stimulate the linear growth colonies of pathogenic fungi: Fusarium avenaceum, Fusarium sambucinum, Fusarium oxysporum. The fungistatic influence of the tested extracts was seen only in relation to Fusarium culmorum. For the coriander extract the inhibition of the surface growth was 61-81% and for the fennel extract 40-79%.
PL
W pracy przedstawiono przegląd metod rozdzielania i oznaczania naftochinonów i polifenoli pochodzących z materiału roślinnego, z wykorzystaniem technik chromatografii w układzie faz odwróconych – RP-TLC (Reversed-Phase Thin Layer Chromatography) oraz RP-HPLC (Reversed-Phase High Performance Liquid Chromatography). Uwzględniono procedury przygotowania próbki, etap rozdzielania, a także kontroli czystości zbieranych frakcji. Próbki materiału roślinnego są z reguóły ekstrahowane rozpuszczalnikami organicznymi dla wydzielania składników nisko- i średniopolarnych, albo wodą dla wyodrębniania składników polarnych. Proces ekstrakcji najczęściej jest wspomagany ultradźwiękami. W ostatnich latach stosowane są do rozdzielania naftochinonów i polifenoli fazy stacjonarne typu RP18 oraz eluenty w postaci mieszaniny wody i metanolu lub acetonitrylu. W przypadku rozdzielania polifenoli, częściej niż przy rozdzielaniu naftochinonów, stosuje się elucję gradientową. Zastosowanie ortogonalnego rozdzielania, realizowanego poprzez rozdzielanie techniką TLC w układzie faz normalnych lub HILIC, składników frakcji uzyskanych techniką RP HPLC, pozwala skutecznie kontrolować efektywność rozdzielania oraz czystość frakcji.
EN
The paper presents a review of naphtoquinones and polyphenols separation and quantitative determination methods using reversed phase chromatographic techniques – Reversed- Phase Thin Layer Chromatography (RP-TLC) and Reversed-Phase High Performance Column Liquid Chromatography (RP-HPLC). The procedures of sample preparation, chromatographic separation, as well as fraction purity control, are described in details. Samples of the plant material are mostly extracted with organic solvents or with water. The extraction processes are usually assisted by sonication. The most popular separation systems include a RP18 stationary phase and eluent which consists water and methanol or acetonitrile. In the case of polyphenols separations, much more of G. Boczkaj, M. Jaszczołt, A. Leman, A. Skrzypczak, A. Królicka, M. Kamiński Camera Separatoria Vol. 3, No 1/2011 88 ten than during naphtoquinones separations, the gradient elution is used. The use of orthogonal separations by NP-TLC or HILIC-TLC separation of the fractions collected during RP-HPLC, gives a possibility for the separation effectiveness and fraction purity control.
PL
Kolejna część cyklu publikacji poświęconych problematyce oczyszczania powietrza. Tematem artykułu jest eksploatacja filtrów stosowanych do oczyszczania powietrza w instalacjach klimatyzacji i wentylacji. W jego części pierwszej („TCHK”, nr 8/2010) omówiona została m. innymi charakterystyka techniczna stosowanych filtrów strony nawiewnej, którymi są: filtry wstępne, filtry dokładne i filtry końcowe – absolutne. W części drugiej materiału przedstawiono filtry strony wyciągowej. Zwrócono uwagę na ocenę stanu technicznego filtrów, a także ważny problem ich wymiany, w tym ochronę zdrowia personelu dokonującego takich operacji. W końcowej części artykułu przedstawiono klasyfikację pomieszczeń czystych.
EN
This is the next paper dealing with the problem of air cleaning. The topic is the maintenance of air cleaning fitters installed in air conditioning and ventilating systems, in the first part (JCHK'. nr 8/2010) the fresh air primary filters, fine filters and absolute filters have been characterized. The second part deals with exhaust air filters. The problems of evaluation of filters technical condition and the procedures of their replacement are discussed. At the end the classification of clean rooms is given
EN
The paper presents the results of a study on allelopathic effect of extracts from Stratiotes aloides on natural lake phytoplankton communities grown outdoor in 40 l containers under natural light conditions. The water and plants were taken from an oxbow lake in spring (when S. aloides plants were submerged) and in summer (when plants were floating on lake water surface). Water extracts were prepared from fresh healthy leaves obtained on both sampling occasions. Control containers were supplemented with N and P in amounts similar to those introduced to experimental containers with macrophyte extracts. That way the experimental set up excluded the possibility of phytoplankton limitation by nutrients. Under such conditions the extracts from S. aloides strongly reduced phytoplankton biomass measured as the concentration of chlorophyll a (from 370 to 141 mg chl. a m[^-3] in spring and from 266 to 50 mg chl. a m[^-3] in summer). The inhibition of phytoplankton growth was indirectly confirmed by higher concentrations of available nutrients in experimental versus control containers. The extracts affected also the spring phytoplankton community structure by selective inhibition of diatoms and, to a less extent, of green algae and Cryptophyceae. Similar response of phytoplankton biomass to extracts obtained from submerged and floating S. aloides might suggest that allelochemicals were the constitutive part of macrophyte tissue and their production was not iduced by competition between macrophyte and algae.
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