Anti-ATR (aa 368-462) polyclonal antibody

A novel nonleaching antimicrobial poly(vinyl alcohol)/poly(hexamethylene guanidine) hydrochloride (PVA/PHMG) hydrogel was prepared with freezing-thawing method. The hydrogen bond interaction between PVA and PHMG confirmed by ATR-FTIR spectra, endowed PVA/PHMG hydrogels with the nonleaching characteristic. These antimicrobial hydrogels behaved above 99.9% of antimicrobial rates against both E. coli and S. aureus, even after washing or soaking in water for 7 days. The PVA-0.100wt%PHMG hydrogel had 120% higher tensile strength than pure PVA hydrogel due to the reinforement of hydrogen bonding between PVA and PHMG. Furthermore, GO (graphene oxide) and SiO2 were respectively added to the PVA-0.100wt% PHMG system to reinforce the mechanical properties. PVA/PHMG/GO hydrogel and PVA/PHMG/SiO2 hydrogel were also prepared via freezing-thawing method. These two composite hydrogels still showed nonleaching antimicrobial properties and the antimicrobial rates were above 99.99% even after washing or soaking in water for 7 days. Compared with PVA/PHMG hydrogel, the -OH peak of the PVA/PHMG/SiO2 hydrogels in the infrared difference spectra shifted to the lower wavenumbers by 38 cm(-1), while the -OH peak of the PVA/PHMG/GO hydrogels shifted by 23 cm(-1). Therefore, the hydrogen bonding effect of SiO2 with PVA/PHMG might be stronger than that of GO. The hydrogen bond interactions among reinforcing agents, PVA and PHMG significantly enhanced the tensile strength of the hydrogel. The tensile strengths of PVA/PHMG/GO and PVA/PHMG/SiO2 hydrogels were 1.6 times and 3.3 times of that of PVA/PHMG hydrogels, respectively. This study provides a simple approach to develop reinforced and nonleaching antimicrobial PVA hydrogels.

Plants are natural sources of several bioactive substances, which have been found in extracts, secondary metabolites, and essential oils. Several biological activities have been attributed to essential oils as antiviral, insecticidal, antiparasitic, antioxidant, and antimicrobial. The indiscriminate use of antibiotics has increased the development of resistance mechanisms of microorganisms. Thus, search for efficient natural compounds with antimicrobial activity and low toxicity has increased, so essential oils have been a promising alternative for combating microbial infections. This study was carried out to investigate the seasonality effects on the infrared absorbance spectra, antibacterial activity, and antibiotic potentiating activity of essential oils fromVitex gardnerianaleaves. Essential oils were extracted fromV. gardnerianaSchauer leaves the seasonal period from January to December 2016 and characterized by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The antibacterial effect of these oils and antibiotic potentiating activity, both determined by the minimum inhibitory concentration, were assessed using microtiter plates. For the first time, we present the use of infrared absorbance spectra of these essential oils and show the influence of seasonality on them. Synergistic effects were observed for the essential oils associated with the antibiotics tested (gentamicin, ampicillin, and ofloxacin). The main influence of seasonality on the infrared absorbance spectra of the essential oils of theV. gardnerianaoccurred in the June month (last month of the rainy season). In regard to antibacterial activity test, the essential oils of theV. gardnerianaleaves did not show a direct effect on the strains tested. However, the essential oils when associated with the antibiotics showed variations in the minimum inhibitory concentration with the months of the seasonal period, indicating synergistic effects againstEscherichia coliandStaphylococcus aureusbacterial resistance