Mg Of Extract Research Articles

Anti-platelet and anti-inflammatory properties of an ethanol-water red grape pomace extract

AbstractPrevious reports support that wine contains a mixture of micro-constituents in a proper quality and quantity that possess cardio-protective effect partly through Platelet-Activating Factor (PAF) inhibition. Grape pomace (GP) is a source of wine-like micro-constituents that may be a suitable alternative in food fortification. Limited data exist concerning their effects on thrombosis and inflammation. Therefore, the purpose of this study was to examine a grape pomace extract regarding its anti-platelet and anti-inflammatory properties. GP from four red grape varieties were extracted with 80% ethanol (GP:solvent 1:5w/v). The extract's total phenolic compounds were evaluated and the phenolic profile was performed by Ultrahigh-Performance-Liquid-Chromatography coupled to Mass-Spectrometry and the determination of fatty acids profile was performed by Gas-Chromatography. The extract's anti-platelet properties were tested in healthy volunteers’ platelet rich plasma by the light transmittance method, against three agonists: PAF, ADP and TRAP. The results expressed as IC50 values (μg of extract that cause 50% inhibition of aggregation) and EC50 values (agonist concentration that causes 50% of the maximum aggregation) in the extract's presence and absence. Concerning the extract's anti-inflammatory properties, peripheral blood mononuclear cells from healthy volunteers were pre-incubated with different extract concentrations, which were tested for their effect on cell viability, for 1 h and then stimulated with LPS for 4 h. Secretion of IL-1β and TNF-a was measured and normalized with the total cell protein. Phenolic compounds were calculated at 8.79 ± 1.17 mg gallic acid per g of GP. The most abundant ones were catechin, epicatechin and quercetin at 202.9 ± 6.9, 84.8 ± 1.5 and 83.7 ± 3.5μg per g of GP respectively. Out of the 18 fatty acids detected, the most abundant ones were palmitic, oleic, linoleic, and linolenic acid at 28.7 ± 0.1, 11.4 ± 0.01, 32.5 ± 0.07, 12.7 ± 0.005 g per 100 g of fat. The extract's IC50 was calculated at 162.1 ± 66.9, 181.2 ± 82.3 and 156.3 ± 97.5μg against PAF, ADP and TRAP, respectively. The EC50 values in the presence of 150μg extract were increased (lower platelet aggregation sensitivity) approximately at 100%, 45% and 13% against PAF, ADP and TRAP respectively, compared to EC50 values in the absence of extract. The presence of 500 and 1000μg/mL of extract reduced LPS-induced TNF-a secretion at approximately 38.2% (p = 0.04) and 6.0% (p < 0.000), respectively. Potent anti-platelet and anti-inflammatory properties are combined in a grape pomace extract. The use of its bioactive micro-constituents is likely to lead to the production of functional foods with cardioprotective properties.

Antiviral effects of extracts from Celosia cristata and Raphanus sativus roots against viral hemorrhagic septicemia virus.

The antiviral activity of an extract mixture from Celosia cristata and Raphanus sativus was tested against viral hemorrhagic septicemia virus (VHSV). Pretreatment of EPC cells with this extract up to 72 h before VHSV infection markedly reduced the virus titer, but it had no effect when added after virus inoculation. In olive flounder that received 5 µg of extract per fish, Mx expression peaked at 48 h after treatment. In contrast, ISG15 and TLR2 expression peaked at 72 h, and that of TLR7 peaked at 48 h, followed by a slight decrease at 72 h, indicating that the antiviral activity was mediated by induction of gene expression involved in the innate immune response.

Phytochemical screening and free radical scavenging activity of Citrullus colocynthis seeds extracts

ObjectiveTo study the phytochemical screening of different extracts from Citrullus colocynthis (C. colocynthis) seeds extracts and to assess their antioxidant activity on the DPPH free radical scavenging. MethodsPhytochemical screening, total content of polyphenols and flavonoids of C. colocynthis seeds extracts, including a crude aqueous extract (E1), a defatted aqueous extract (E2), a hydromethanolic extract (HM), an ethyl acetate extract (EA) and a n-butanol extract (n-B) was carried out according to the standard methods and to assess their corresponding effect on the antioxidant activity of this plant. ResultsNone of these extracts contained detectable amount of alkaloid, quinone, antraquinone, or reducing sugar. Catechic tannins and flavonoids were abundant in E1, HM and EA, whilst terpenoids were abundantly present in E1 and n-B but only weekly in HM. Coumarins were found in E2, EA and n-B. Polyphenols, expressed as gallic acid equivalent, amounted, per 100 g plant matter, to 329, 1002 and 150 mg in EA, HM an E1 respectively. Flavonoids, expressed as catechin equivalent, amounted, per 100 g plant matter to 620, 241 and 94 mg in EA, HM and E1 respectively. Comparable values were found in n-B and E1, with lower values in E2. Quercetin, myricetin and gallic acid were found in the EA and HM extracts by thin layer chromatography, The antioxidative effect of these extracts yielded, when tested at a concentration of 2 000 μg/mL in a 1,1-diphenyl-2-picrylhydrazyl assay, a reducing percentage of 88.8% with EA, 74.5% with HM and 66.2% with E1, and corresponding IC50 of 350, 580 and 500 μg/mL as compared to 1.1 μg/mL for ascorbic acid. ConclusionsThese qualitative and quantitative analytical data document the presence in C. colocynthis extracts of such chemical compounds as flavonoids responsible for the antioxidant activity, as well as other biological activities of this plant.

Inhibition of Essential Bacterial Peptidyl-tRNA Hydrolase Activity by Tropical Plant Extracts

Peptidyl-tRNA Hydrolase (Pth) is a highly conserved, essential enzyme in bacteria. It removes the peptide portion from peptidyl-tRNA, returning free tRNAs to participate in translation. Build-up of peptidyl-tRNAs is toxic and defects in Pth function result in cell death. Herein we use in vitro activity of recombinant E. coli Pth to screen tropical plant extracts for inhibition. Multiple extracts were found to have inhibitory activity with some exhibiting different inhibitory effects depending on extraction conditions. IC50 values ranged from 0.02 to > 53.8 microg of extract per 1 unit of Pth, holding promise for in vivo screening. The inhibitory components in these extracts may serve as lead compounds for development of novel antibacterials.

Direct Ubiquitination of β-Catenin by Siah-1 and Regulation by the Exchange Factor TBL1

Beta-catenin is a key component of the Wnt signaling pathway that functions as a transcriptional co-activator of Wnt target genes. Upon UV-induced DNA damage, beta-catenin is recruited for polyubiquitination and subsequent proteasomal degradation by a unique, p53-induced SCF-like complex (SCF(TBL1)), comprised of Siah-1, Siah-1-interacting protein (SIP), Skp1, transducin beta-like 1 (TBL1), and adenomatous polyposis coli (APC). Given the complexity of the various factors involved and the novelty of ubiquitination of the non-phosphorylated beta-catenin substrate, we have investigated Siah-1-mediated ubiquitination of beta-catenin in vitro and in cells. Overexpression and purification protocols were developed for each of the SCF(TBL1) proteins, enabling a systematic analysis of beta-catenin ubiquitination using an in vitro ubiquitination assay. This study revealed that Siah-1 alone was able to polyubiquitinate beta-catenin. In addition, TBL1 was shown to play a role in protecting beta-catenin from Siah-1 ubiquitination in vitro and from Siah-1-targeted proteasomal degradation in cells. Siah-1 and TBL1 were found to bind to the same armadillo repeat domain of beta-catenin, suggesting that polyubiquitination of beta-catenin is regulated by competition between Siah-1 and TBL1 during Wnt signaling.

Constitutive Production of NF-κB2 p52 Is Not Tumorigenic but Predisposes Mice to Inflammatory Autoimmune Disease by Repressing Bim Expression

Normal development of the immune system requires regulated processing of NF-kappaB2 p100 to p52, which activates NF-kappaB2 signaling. Constitutive production of p52 has been suggested as a major mechanism underlying lymphomagenesis induced by NF-kappaB2 mutations, which occur recurrently in a variety of human lymphoid malignancies. To test the hypothesis, we generated transgenic mice with targeted expression of p52 in lymphocytes. In contrast to their counterparts expressing the tumor-derived NF-kappaB2 mutant p80HT, which develop predominantly B cell tumors, p52 transgenic mice are not prone to lymphomagenesis. However, they are predisposed to inflammatory autoimmune disease characterized by multiorgan infiltration of activated lymphocytes, high levels of autoantibodies in the serum, and immune complex glomerulonephritis. p52, but not p80HT, represses Bim expression, leading to defects in apoptotic processes critical for elimination of autoreactive lymphocytes and control of immune response. These findings reveal distinct signaling pathways for actions of NF-kappaB2 mutants and p52 and suggest a causal role for sustained NF-kappaB2 activation in the pathogenesis of autoimmunity.

Effects of filter loading and filter type on the mutagenicity and composition of diesel exhaust particulate extracts

Diesel vehicle exhaust particles were simultaneously collected from a dilution tube on three commonly used types of filters. Sampling was performed over single cycles and over 7 or 10cycles of the 1974 Hot-start Federal Test Procedure (FTP/H). Particulate loadings on the filters ranged from 48 to 660 μg cm −2. The filters were extracted with dichloromethane and the extracts were characterized by the Ames Salmonella-histidine reversion assay (strains TA98 and TA 100, without microsomal activation) and by high performance liquid chromatography (HPLC) with fluorescence detection. It was found that the extracts from lightly loaded filters of the three types were indistinguishable. A similar conclusion obtains for the heavily loaded filters, confirming our results from an earlier study (Clark C. R., Truex T. J., Lee K. S. C. and Salmeen I. T. et al., 1981 Atmospheric Environment 15, 397–402). The percentage of extractable material in the paniculate matter, the fluorescent intensities of two of the four HPLC fractions and the Ames assay activities (revertants per μg of extract) each increase linearly with paniculate loading on the filters. We attribute these increases to reactions between the particle-bound organic material and reactive gases in the exhaust stream.