Increased carbon disulfide-stimulated chemiluminescence in the pyrogallol-luminol system

Antioxidant and Antimicrobial Activity of Ophiurasaponin Extracted fromOphiopholis mirabilis

The aim of this study was to analyze antioxidant and antimicrobial activity of ophiurasaponin extracted fromOphiopholis mirabilis(overall). Ophiurasaponin was extracted with solvent extraction and purified through AB-8 macroporous resin, silica gel column chromatography, Sephadex LH-20 gel column chromatography, and C18 ODS column chromatography. The antioxidant activity of ophiurasaponin was detected by the chemiluminescence assay. The paper filtering method and the modified agar dilution method were used to determine antimicrobial activity. The results showed that the content of crude ophiurasaponin and the refined ophiurasaponin was 46.75% and 96.72%, respectively. The values of the IC50of hydroxyl-radicals, superoxide anions, and peroxide were 25.54 mg/mL, 9.98 mg/mL, and 1.37 mg/mL, respectively. The refined ophiurasaponin had a good inhibitory effect onEscherichia coli,Bacillus subtilis,Staphylococcus aureus,Aerobacter aerogenes,andProteusbacillus vulgaris, and the minimum inhibitory concentration (MIC) was 0.0443 mg/mL. In conclusion, ophiurasaponin fromOphiopholis mirabilishad obvious antioxidant activities and antimicrobial activities which could provide the theoretical basis for further research and development of antioxidant and antimicrobial marine drugs.

Quinic acid could be a potential rejuvenating natural compound by improving survival of Caenorhabditis elegans under deleterious conditions

Quinic acid (QA) is an active ingredient of Cat's Claw (Uncaria tomentosa), which is found to be active in enhancing DNA repair and immunity in model systems and able to generate neuroprotective effects in neurons. However, QA's role in improving survival is not well studied. Here we report that QA can provide protection in Caenorhabidits elegans and improve worm survival under stress. Under heat stress and oxidative stress, QA-treated wild-type C. elegans N2 (N2) survived 17.8% and 29.7% longer, respectively, than the control worms. Our data suggest that under heat stress, QA can upregulate the expression of the small heat shock protein hsp-16.2 gene, which could help the worms survive a longer time. We also found that QA extended the C. elegans mutant VC475 [hsp-16.2 (gk249)] life span by 15.7% under normal culture conditions. However, under normal culture conditions, QA did not affect hsp-16.2 expression, but upregulated the expression of daf-16 and sod-3 in a DAF-16-dependent manner, and downregulated the level of reactive oxygen species (ROS), suggesting that under normal conditions QA acts in different pathways. As a natural product, QA demonstrates great potential as a rejuvenating compound.

Significant longevity-extending effects of EGCG on Caenorhabditis elegans under stress

Epigallocatechin gallate (EGCG), a main active ingredient of green tea, is believed to be beneficial in association with anticarcinogenesis, antiobesity, and blood pressure reduction. Here we report that EGCG extended Caenorhabditis elegans longevity under stress. Under heat stress (35 degrees C), EGCG improved the mean longevity by 13.1% at 0.1 microg/ml, 8.0% at 1.0 microg/ml, and 11.8% at 10.0 microg/ml. Under oxidative stress, EGCG could improve the mean longevity of C. elegans by 172.9% at 0.1 microg/ml, 177.7% at 1.0 microg/ml, and 88.5% at 10.0 microg/ml. However, EGCG could not extend the life span of C. elegans under normal culture conditions. Further studies demonstrated that the significant longevity-extending effects of EGCG on C. elegans could be attributed to its in vitro and in vivo free radical-scavenging effects and its up-regulating effects on stress-resistance-related proteins, including superoxide dismutase-3 (SOD-3) and heat shock protein-16.2 (HSP-16.2), in transgenic C. elegans with SOD-3::green fluorescent protein (GFP) and HSP-16.::GFP expression. Quantitative real-time PCR results showed that the up-regulation of aging-associated genes such as daf-16, sod-3, and skn-1 could also contribute to the stress resistance attributed to EGCG. As the death rate of a population is closely related to the mortality caused by external stress, it could be concluded that the survival-enhancing effects of EGCG on C. elegans under stress are very important for antiaging research.

Optimization of peroxynitrite-luminol chemiluminescence system for detecting peroxynitrite in cell culture solution exposed to carbon disulphide

We established a peroxynitrite-luminol chemiluminescence system for detecting peroxynitrite in cell culture solution exposed to carbon disulphide (CS(2)). Three factors, including exposure time to ozone (Factor A), volume of peroxynitrite (ONOO(-)) solution (Factor B) and luminol concentrations (Factor C) at three levels were selected and the combinations were in accordance with orthogonal design L(9) (3(4)). Peroxynitrite was generated from the reaction of ozone and 0.01 mol/L sodium azide (NaN(3)) dissolved in carbonic acid buffer solution (pH 11), and it was reacted with luminol to yield chemiluminescence. The peak value, peak time and kinetic curve of the light emission were observed. The selected combination conditions were 50 s ozone, 800 micro L peroxynitrite and 0.001 mol/L luminol solution. Cell culture solution with CS(2) enhanced the emission intensity of chemiluminescence (F = 8.38, p = 0.018) and shortened the peak time to chemiluminescence (F = 139.00, p = 0.0001). The data demonstrated that this luminol chemiluminescence system is suitable for detecting peroxynitrite in cell culture solutions for evaluating the effect of CS(2) on endothelial cells.