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1.
The possibility of using mycosporine-like amino acids (MAAs), with an apparent sunscreen function in nature, as ultraviolet radiation (UVR) blockers to prevent skin injury has been raised by diverse authors. Production of MAAs by the dinoflagellate Heterocapsa sp. (Dinophyceae) is shown here. Three major peaks with absorption maxima at 330.8, 332.0 and 333.2 nm were detected by high performance liquid chromatography (HPLC) analysis of methanolic extracts in all tested conditions. Analysis of crude extract by mass spectroscopy with electrospray ionization (MS-EI) showed a set of molecular ions ([M+H](+)) with main peaks being at m/z 242.4, 288.4, 303.3 and 333.3 u.m.a. According to these data, along with retention times, the MAA profile of Heterocapsa sp. is assumed to be composed of shinorine (lambda(max)=334 nm), mycosporine-2-glycine (lambda(max)=331 nm) and palythinol (lambda(max)=332 nm). A constitutive MAA content of about 4 microg (10(6) cells)(-1) was measured under exposure to PAR only. A maximal accumulation of MAA per culture volume of 1.1 mg l(-1) was obtained after 72 h of exposure to PAR+UVA, while the highest production rate (0.025 mg l(-1) h(-1)) was computed after 24 h of exposure to PAR+UVA+UVB.  相似文献   

2.
The crude methanolic extract and chloroform, ethyl acetate and n-butanol fractions of Teucrium royleanum were examined as inhibitors of actylcholinesterase, butyrylcholinesterase, lipoxygenase and urease. A significant enzyme inhibition activity (52-83%) was shown by the crude methanolic extract and its fractions against acetylcholinesterase, while low to outstanding enzyme inhibitory activity was shown (19-93%) against butyrylcholinesterase. The crude methanolic extract and its various fractions demonstrated low activity against lipoxygenase and inactive against urease.  相似文献   

3.
The crude methanolic extract and various fractions of Andrachne cardifolia Muell, including chloroform, ethyl acetate and n-butanol fractions were subjected to in vitro enzyme inhibition activity against acetylcholinesterase, butyrylcholinesterase, lipoxygenase and urease enzymes. A significant enzyme inhibition activity (40-89%) was shown by the crude methanolic extract and its fractions against lipoxygenase, while low to significant activity (40-71%) against butyrylcholinesterase. The crude methanolic extract and its various fractions demonstrated poor to significant activity (25-73%) against acetylcholinesterase and no activity against urease.  相似文献   

4.
In vitro enzymes inhibition activities of the crude methanolic extract and various fractions of Colchicum luteum Baker (Liliaceae) including chloroform, ethyl acetate, n-butanol and aqueous were carried out against actylcholinesterase, butyrylcholinesterase, lipoxygenase and urease enzymes. A significant enzyme inhibition activity (89%) is shown by the crude methanolic extract and its fractions against lipoxygenase, while low to significant activity (32-75%) was evident against butyrylcholinesterase. The crude methanolic extract and its various fractions demonstrated low activity (29-61%) against acetylcholinesterase and no activity against urease.  相似文献   

5.
The crude methanolic extract and chloroform, ethyl acetate and n-butanol fractions of Teucrium royleanum were examined as inhibitors of actylcholinesterase, butyrylcholinesterase, lipoxygenase and urease. A significant enzyme inhibition activity (52–83%) was shown by the crude methanolic extract and its fractions against acetylcholinesterase, while low to outstanding enzyme inhibitory activity was shown (19–93%) against butyrylcholinesterase. The crude methanolic extract and its various fractions demonstrated low activity against lipoxygenase and inactive against urease.  相似文献   

6.
A new ursanolide, 3beta-O-alpha-L-rhamnopyranosyl-(1->2)-O-alpha-L-arabinopyranosyl-(1->2)-beta-D-glucopyranosyl)oxy]-ursan-20beta,28-olide, zygophyloside N (1), and three known quinovic acid glycosides were isolated from the methanolic extract of the roots of Zygophyllum gaetulum. The crude extract, some fractions and 3-O-beta-D-glucopyranosyl quinovic acid 28-beta-D-glucopyranosyl ester, significantly and dose-dependently, are able to reduce the electrically-induced contractions of isolated guinea-pig ileum. The structure of compound (1) was determined, using 1D and 2D NMR techniques.  相似文献   

7.
Medicinal plants have significant contribution in pharmaceutical industries being producers of compounds utilized as precursors for drug development. A plant of Lamiaceae family; Pseudocaryopteris foetida had not been investigated for its biomedical potential. Current research was aimed to investigate phytochemical analysis, cytotoxic potential and antioxidant activity of crude methanolic extract and fractions of Pseudocaryopteris foetida (leaves). The preliminary phytochemical analysis of crude methanolic extracts and fractions of Pseudocaryopteris foetida revealed that plant is rich in phenolic and flavonoid classes of secondary metabolites while presence of tannin was observed only in crude methanolic extract. The cytotoxicity was determined using brine shrimp lethality test. Different concentrations (25, 50, 100, 150, 200 and 250 µg/mL) of crude methanolic extract and fractions exhibited dose dependent cytotoxicity. However, The LD50 for all the extracts was more than 200 µg/mL indicating weak cytotoxic potential of Pseudocaryopteris foetida. The antioxidant capabilities of crude methanolic extract and fraction of Pseudocaryopteris foetida were analyzed by in vitro bio assays including DPPH, ABTS, Reducing power and phosphomolybdate antioxidant assays using ascorbic acid as standard. The crude methanolic extract showed IC50 (256.38 ± 0.6 and 314.95 ± 1.1 µg/mL) for DPPH and ABTS respectively, while total antioxidant capacity was calculated as 55.79 ± 0.5 µg/mL for crude methanolic extract of Pseudocaryopteris foetida while ascorbic acid indicated total antioxidant capacity of 71.89 ± 2.3 µg/mL. Study concluded that leaves of Pseudocaryopteris foetida were the rich source of antioxidant phytochemicals. Based on preliminary investigations further research should be focused to isolate bioactive phytochemicals as leading source of clinical medicines in future.  相似文献   

8.
Medicinal plants have significant contribution in pharmaceutical industries being producers of compounds utilized as precursors for drug development. A plant of Lamiaceae family; Pseudocaryopteris foetida had not been investigated for its biomedical potential. Current research was aimed to investigate phytochemical analysis, cytotoxic potential and antioxidant activity of crude methanolic extract and fractions of Pseudocaryopteris foetida (leaves). The preliminary phytochemical analysis of crude methanolic extracts and fractions of Pseudocaryopteris foetida revealed that plant is rich in phenolic and flavonoid classes of secondary metabolites while presence of tannin was observed only in crude methanolic extract. The cytotoxicity was determined using brine shrimp lethality test. Different concentrations (25, 50, 100, 150, 200 and 250 µg/mL) of crude methanolic extract and fractions exhibited dose dependent cytotoxicity. However, The LD50 for all the extracts was more than 200 µg/mL indicating weak cytotoxic potential of Pseudocaryopteris foetida. The antioxidant capabilities of crude methanolic extract and fraction of Pseudocaryopteris foetida were analyzed by in vitro bio assays including DPPH, ABTS, Reducing power and phosphomolybdate antioxidant assays using ascorbic acid as standard. The crude methanolic extract showed IC50 (256.38 ± 0.6 and 314.95 ± 1.1 µg/mL) for DPPH and ABTS respectively, while total antioxidant capacity was calculated as 55.79 ± 0.5 µg/mL for crude methanolic extract of Pseudocaryopteris foetida while ascorbic acid indicated total antioxidant capacity of 71.89 ± 2.3 µg/mL. Study concluded that leaves of Pseudocaryopteris foetida were the rich source of antioxidant phytochemicals. Based on preliminary investigations further research should be focused to isolate bioactive phytochemicals as leading source of clinical medicines in future.  相似文献   

9.
The antibacterial activity of the methanolic extract and its fractions of aerial parts of Aniheinis tinctoria (Asteraceae) was investigated against representative gram-positive Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 29212) and gram-negative strains Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853). The activity was concentrated mainly in the dichloromethane (DCM) and hexane fractions of crude methanolic extract. The 5 mg of DCM extract per disk produced 15-16 mm of inhibition zone against S. aureus and P. aeruginosa, however, no activity was found against E. faecalis and E. coli. The hexane fraction showed activity against S. aureus, P. aeruginosa and E. faecalis. As DCM fraction showed the highest antibacterial activity in the disk diffusion assay, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of only this fraction was determined against S. aureus and P. aeruginosa. These values were found to be in the range of 1.25 to 10 mg/ml.  相似文献   

10.
In vitro enzymes inhibition activities of the crude methanolic extract and various fractions of Colchicum luteum Baker (Liliaceae) including chloroform, ethyl acetate, n-butanol and aqueous were carried out against actylcholinesterase, butyrylcholinesterase, lipoxygenase and urease enzymes. A significant enzyme inhibition activity (89%) is shown by the crude methanolic extract and its fractions against lipoxygenase, while low to significant activity (32–75%) was evident against butyrylcholinesterase. The crude methanolic extract and its various fractions demonstrated low activity (29–61%) against acetylcholinesterase and no activity against urease.  相似文献   

11.
Marine algae are rich sources ofbioactive compounds capable of harboring secondary metabolites which are structurally and biologically active. In our study, the methanolic extract of marine algae Caulerpa racemosa (green algae) was employed to determine the antibacterial and larvicidal activity. The antibacterial activity showed effective inhibition against five pathogenic bacteria. A significant zone size of 16 mm was observed for Pseudomonas aeruginosa. The methanolic extract of Caulerpa racemosa showed effective larvicidal activity against Culex tritaeniorhynchus and the histopathological studies revealed the rupture in mid gut of larvae. The bioactive compounds in the crude extract were further identified as 2-(-3-bromo-1-adamantyl) acetic acid methyl ester and Chola-5, 22- dien-3-ol by GC-MS. Hence the bioactive compounds obtained from the methanolic extracts could be used for the bactericidal and larvicidal activity which will overcome the harmful impact of synthetic insecticide on environment.  相似文献   

12.
Currently, the research and development of sunscreens play an important role on the synthesis of actives that are stable in various kinds of formulations—in addition to their efficiency and broad spectrum of protection against ultraviolet radiation. Our objective here was to synthesize new sunscreening chemical agents using quinoline as a base molecule. Twelve quinoline derivatives were synthesized, four of them novel molecules, and their photoprotective activity was determined in vitro using diffuse transmittance spectrophotometry. We determined their SPF, UVAPF, UVA/UVB ratio, critical wavelength and Boots Star Rating. The quinolines derivatives presented a varied profile of photoprotection, their SPF ranging from 2 to 11 and their UVAPF from 2 to 7. In terms of the critical wavelength, all molecules were considered of broad-spectrum by different classifications. Regarding the Boots Star Rating, one compound received no rating, seven of them received a three stars rating, three received a four stars rating and three were given a five stars rating. The molecules showed in the present work have a wide range of possibilities for creating new sunscreen products, once they have good SPF or UVAPF for single molecules, and they also possess other different qualities that can act synergistically.  相似文献   

13.
Aphanizomenon flos-aquae (AFA) is a fresh water unicellular blue-green alga (cyanophyta) rich in phycocyanin (PC), a photosynthetic pigment with antioxidant and anti-inflammatory properties. The purpose of this study was to evaluate the ability of a novel natural extract from AFA enriched with PC to protect normal human erythrocytes and plasma samples against oxidative damage in vitro. In red blood cells, oxidative hemolysis and lipid peroxidation induced by the aqueous peroxyl radical generator [2,2'-Azobis (2-amidinopropane) dihydrochloride, AAPH] were significantly lowered by the AFA extract in a time- and dose-dependent manner; at the same time, the depletion of cytosolic glutathione was delayed. In plasma samples, the natural extract inhibited the extent of lipid oxidation induced by the pro-oxidant agent cupric chloride (CuCl2); a concomitant increase of plasma resistance to oxidation was observed as evaluated by conjugated diene formation. The involvement of PC in the antioxidant protection of the AFA extract against the oxidative damage was demonstrated by investigating the spectral changes of PC induced by AAPH or CuCl2. The incubation of the extract with the oxidizing agents led to a significant decrease in the absorption of PC at 620 nm accompanied with disappearance of its blue color, thus indicating a rapid oxidation of the protein. In the light of these in vitro results, the potential clinical applications of this natural compound are under investigation.  相似文献   

14.
The rapid evaluation of antioxidant activity of crude borage (Borago officinalis L.) extract was determined by using DPPH free radical method. This borage extract resulted in a rapid decrease of the absorbance and showed very high hydrogen-donating capacity towards the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical. A new HPLC-DPPH on-line method was applied for a screening of several radical scavenging components in this borage extract as well as for quantitative analysis. This on-line HPLC-DPPH method was developed using a methanolic solution of DPPH-stable radical. The HPLC-separated analytes reacted post-column with the DPPH solution in methanol. The induced bleaching was detected as a negative peak photometrically at 515 nm. The separation of antioxidative components was carried out by gradient HPLC with mobile-phase composition ranging from 2% to 80% acetonitrile with 2% acetic acid in water, UV detection was carried out at 280 nm. The HPLC analysis of borage extract revealed the presence of several radical scavenging components in the borage extract. The results obtained from the chromatograms suggest that some compounds present in the extract possess high radical quenching ability. The dominant antioxidative compound in the crude extract of borage leaves was identified as rosmarinic acid.  相似文献   

15.
The crude methanolic extract of Andrachne cordifolia Muell. (Euphorbiaceae) and its various fractions in different solvent systems (chloroform, ethyl acetate and n- butanol) were screened for antibacterial and antifungal activities. Crude extract and subsequent fractions demonstrated moderate to excellent antibacterial activities against the tested pathogens. Highest antibacterial activity was displayed by both chloroform and ethyl acetate fractions (100%) followed by the crude extract (68%) against Salmonella typhi. Similarly, crude extract and its subsequent fractions showed mild to excellent activities in antifungal bioassay with maximum (76%) antifungal activity against Microsporum canis by the chloroform fraction followed by the crude extract (65%).  相似文献   

16.
Molecular Biology Reports - Cytotoxic activities of methanolic crude extract of Stachys parviflora (Lamiaceae family) and its sub-fractions were primarily evaluated against human breast...  相似文献   

17.
N. Pugh  D.S. Pasco 《Phytomedicine》2001,8(6):445-453
Aphanizomenon flos-aquae (AFA) is a fresh-water microalgae that is consumed as a nutrient-dense food source and for its health-enhancing properties. The current research characterizes the effect of a water soluble preparation from AFA on human monocyte/macrophage function and compares the effect of AFA with responses from known agents that modulate the immune system. At 0.5 μg/ml the AFA extract robustly activated nuclear factor kappa B (NF-kappa B) directed luciferase expression in THP-1 human monocytic cells to levels at 50% of those achieved by maximal concentrations (10 μg/ml) of bacterial lipopolysaccharide (LPS). In addition, the AFA extract substantially increased mRNA levels of interleukin-1β(IL-1β) and tumor necrosis factor-(TNF-), and enhanced the DNA binding activity of NF-kappa B. The effects of AFA water soluble preparation were similar to the responses displayed by LPS, but clearly different from responses exhibited by tetradecanoyl phorbol acetate (TPA) and interferon-gamma (INF-γ). Pretreatment of THP-1 monocytes with factors known to induce hyporesponsiveness suppressed both AFA-dependent and LPS-dependent activation. These results suggest that the macrophage-activating properties of the AFA water soluble preparation are mediated through pathways that are similar to LPS-dependent activation.  相似文献   

18.
A capillary electrophoretic method for the quantification of free and total apigenin in methanolic, ethanolic and glycolic extracts of Chamomilla recutita L. Rauschert (Asteraceae) is described. The method was validated for measurement of apigenin in the range 5.00-300 microg/mL (r2 = 0.993) and showed coefficients of intra-day (replicability) and inter-day (repeatability) variability of better than 2%. The limits of detection and quantification were 3.80 and 11.5 microg/mL, respectively, and the average recovery was 102.0 +/- 0.8% at three concentration levels of apigenin. Free and total apigenin contents in the extracts were, respectively, determined as 106 and 903 microg/g (methanolic extract), 77 and 817 microg/g (ethanolic extract) and 11.0 and 247 microg/g (glycolic extract).  相似文献   

19.
UVA1-induced expression of matrix metalloproteinase-1 (MMP-1) is mediated by an autocrine mechanism involving the cytokines interleukin-1 and -6 (IL-1 and IL-6). The subsequent degradation of collagen fibers is thought to be the main cause of skin wrinkling. As it is currently not known which wavelengths within the UVA1 range are responsible for these effects, we have assessed 5 UVA1 filters (experimental filters HRH21328 and HRH22127, butyl methoxydibenzoylmethane (BMDM), diethylaminohydroxybenzylbenzoic acid hexyl ester (DHBB) and anisotriazine) with different absorption maxima for their capacity to protect against UVA1-induced MMP-1 expression. To test the efficacy of these hydrophobic filters in a cell culture system, UVA1 irradiation of primary human fibroblasts was performed through a quartz microplate filled with ethanolic solutions of the UVA filters placed on top of the cell microplate. Inhibition of UVA1-induced gene expression was detected by real time RT-PCR. The efficacy to protect against UVA1-induced MMP-1 expression was wavelength dependent: the protection by HRH22127 was best, followed by HRH21328, DHBB, BMDM, and anisotriazine. In addition, HRH22127 and HRH 21328 both significantly inhibited UVA1-induced expression of IL-1alpha and IL-6 with HRH21238 being superior to HRH22127. These studies indicate that UVA1 filters with a maximum absorption at > or =360 nm are most effective in preventing UVA1 radiation-induced MMP-1, IL-1alpha, and IL-6 expression pointing towards a critical role for effective filtering beyond > or =360 nm for protection against UVA1-induced photoaging.  相似文献   

20.
The crude methanolic extract of Andrachne cordifolia Muell. (Euphorbiaceae) and its various fractions in different solvent systems (chloroform, ethyl acetate and n-butanol) were screened for antibacterial and antifungal activities. Crude extract and subsequent fractions demonstrated moderate to excellent antibacterial activities against the tested pathogens. Highest antibacterial activity was displayed by both chloroform and ethyl acetate fractions (100%) followed by the crude extract (68%) against Salmonella typhi. Similarly, crude extract and its subsequent fractions showed mild to excellent activities in antifungal bioassay with maximum (76%) antifungal activity against Microsporum canis by the chloroform fraction followed by the crude extract (65%).  相似文献   

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