A modified method for studying behavioral paradox of antioxidants and their disproportionate competitive kinetic effect to scavenge the peroxyl radical formation

Antioxidant and Anti-Inflammatory Activities of Stellera chamaejasme L. Roots and Aerial Parts Extracts

Natural products, mainly plants, have a crucial role in folk medicine. Particularly, Stellera chamaejasme L. has been traditionally used in Mongolian medicine to treat various diseases, including chronic tracheitis, tuberculosis, and psoriasis. In this study, ethanol (EtOH) and dichloromethane (DCM) extracts of its roots (R) and aerial parts (AP) were evaluated for their antioxidant and anti-inflammatory activities. Thin-layer chromatography demonstrated the presence of flavonoids, namely kaempferol and quercetin-3-O-glucopyranoside, only in the EtOH-AP. Conversely, it showed that kaempferol, quercetin-3-O-glucopyranoside, coumarin, luteolin, rutin, morin, and riboflavin were not present in the other three extracts. The S. chamaejasme extracts exhibited strong antioxidant activity. In addition, the roots extracts presented the highest antioxidant activity against peroxyl radicals, with the EtOH-R being the most potent (IC50 = 0.90 ± 0.07 µg/mL). S. chamaejasme extracts also efficiently inhibited the production of one of the main pro-inflammatory cytokines, interleukin (IL)-6, in a dose-dependent manner by lipopolysaccharide-stimulated macrophages. Particularly, DCM-R was the strongest extract, reducing ≈ 91.5% of the IL-6 production. Since this extract was the most effective, gas chromatography-mass spectrometry (GC-MS) analyses were performed and demonstrated the presence of two fatty acids (palmitic acid and 9-octadecenoic acid), one fatty alcohol (1-hexadecanol), and one triterpenoid (squalene) that can contribute to the observed bioactivity. Herewith, S. chamaejasme extracts, mainly DCM-R, exhibit antioxidant and anti-inflammatory activities that could be applied as new and innovative natural formulations for the treatment of chronic inflammatory diseases.

DNA-protection and antioxidant properties of fermentates from Bacillus amyloliquefaciens B-1895 and Bacillus subtilis KATMIRA1933

DNA protective and antioxidant activity of Bacillus amyloliquefaciens B-1895 and Bacillus subtilis KATMIRA1933 were evaluated by Escherichia coli-based Lux biosensors. Two biosensor strains of E. coli, MG1655 (pColD-lux) and MG1655 (pSoxS-lux), which react on DNA damage and superoxide-anion radical activity, were used. SOS-response and Sox-response were stimulated by addition of dioxidine (2,3-Quinoxalinedimethanol,1,4-dioxide) and paraquat (N,N'-dimethyl-4,4'-bipyridinium dichloride) respectively. Preparations of both Bacillus fermentates demonstrated DNA protective and antioxidant (superoxide scavenging) activity (up to 60·19%). The strain К1933 is, in general, characterized by higher DNA protective activity (28·85%), with parameters of antioxidant activity of both bacilli strains being statistically not significantly different. Sporogenous potential probiotic micro-organisms with antioxidant and DNA protective activities can become an effective tool for compensation of various negative oxidative stress processes in humans.

SIGNIFICANCE AND IMPACT OF THE STUDY

In humans, oxidative stress is a cause or an important component of many serious diseases, as well as being one of the age influencing factors. Environmental stresses lead to the increase in levels of reactive oxygen species (ROS). Oxidative DNA damage is a side effect of nonspecific inflammation. These human health challenging factors trigger the search for health-promoting bacteria capable of production of antioxidants and DNA-protectors. In this study, two Bacillus strains of interest were shown to produce noticeable DNA protective and antioxidant activities.