13 research outputs found
Antioxidant Activities of Plumbagin and Its Cu (II) Complex
Plumbagin and its Cu (II) complex [Cu (plumbagin)2]·H2O have been synthesized, and their antioxidant activities towards the inhibitory effect on DPPH free radical, reducing power, total antioxidant capacity, and inhibition on lipid peroxidation were investigated. Plumbagin and its Cu (II) complex were found to exhibit scavenging activities on DPPH radical with the inhibitory rate of 41% and 24%, respectively. The reducing power of plumbagin was outstanding at the concentrations of 1.0, 1.5, and 2.0 mg/mL, compared to Cu (II) complex and synthetic antioxidant 2,6-di-ter-butyl-4-methylphenol (BHT); the highest level reached 1.333 for plumbagin and 0.581 for Cu (II) complex. Also, the inhibition on lipid peroxidation of plumbagin was higher than that of Cu (II) complex and BHT, 46.4% for plumbagin and 24.5% for Cu (II) complex. The results give a strong impact for designing anticancer drugs, combined with their potential cytotoxic and antioxidant activities, which can be targeted selectively against cancer cells and increase their therapeutic index and additional advantages over other anticancer drugs
Synthesis, Cytotoxic Activity, and DNA Binding Properties of Copper (II) Complexes with Hesperetin, Naringenin, and Apigenin
Complexes of copper (II) with hesperetin, naringenin, and apigenin of general composition [CuL(2)(H(2)O)(2)] ⋅ nH(2)O (1–3) have been synthesized and characterized by elemental analysis, UV-Vis, FT-IR, ESI-MS, and TG-DTG thermal analysis. The free ligands and the metal complexes have been tested in vitro against human cancer cell lines hepatocellular carcinoma (HepG-2), gastric carcinomas (SGC-7901), and cervical carcinoma (HeLa). Complexes 1 and 3 were found to exhibit growth inhibition of SGC-7901 and HepG2 cell lines with respect to the free ligands; the inhibitory rate of complex 1 is 43.2% and 43.8%, while complex 3 is 46% and 36%, respectively. The interactions of complex 1 and its ligand Hsp with calf thymus DNA were investigated by UV-Vis, fluorescence, and CD spectra. Both complex 1 and Hsp were found to bind DNA in intercalation modes, and the binding affinity of complex 1 was stronger than that of free ligand
Fluorescence Spectroscopy Study on the Interaction between Evodiamine and Bovine Serum Albumin
The interaction of evodiamine (Evo) with bovine serum albumins (BSAs) at different two temperatures (298 and 310 K) was investigated by means of fluorescence spectroscopy. The experimental results showed that Evo binds with BSA via a static quenching procedure with association constants K of 1.61×106 L/mol at 298 K and 6.78×105 L/mol at 310 K. The number of bound Evo molecules per protein is 1.31 at 298 K and 1.33 at 310 K. The results suggested that Evo reacts with BSA chiefly through hydrophobic and electrostatic interactions, and it does not alter the α-helical nature of BAS
Get Your Sexy Back : an Awareness Campaign seeking to educate youth in Singapore on the effects and consequences of binge drinking.
This paper presents the collaboration between a group of four final-year students from the Wee Kim Wee School of Communication and Information, Nanyang Technological University, and local brewer, Asia Pacific Breweries Singapore. The communications campaign set out to increase awareness of the issue of binge drinking among youth aged 18 to 25 in Singapore. This paper includes conclusive research that shaped the direction of communication plans, detailed strategies and mechanics, and an evaluation of the team's efforts.Kavita Karan.Bachelor of Communication Studie
Promotion of Biogasification Efficiency by Pretreatment and Bioaugmentation of Corn Straw with Microbial Consortium
To better understand the comparative effects between pretreatment and bioaugmentation methods on the promotion of corn straw biogasification efficiency, we analysed the cellulase activity, cellulose degradation rate, surface structure characteristics, and biogas production of corn straw that had been pretreated with aerobic microbial consortium (AMC). In addition, we also studied the effect of bioaugmentation using anaerobic microbial consortium (ANMC) on corn straw biogasification efficiency. The results from our study demonstrated that the cumulative methane generated from AMC and ANMC were 233.09 mL·g-1 VS and 242.56 mL·g-1 VS, which was increased compared to the control by 6.89% and 11.23%, respectively. We also observed that ANMC could also function to dramatically promote methane content during the anaerobic digestion of corn straw. This study demonstrated that AMC and ANMC were both able to promote the biogasification efficiency of corn straw, however, ANMC was found to perform better compared to AMC
Chinese-Style Fiscal Decentralization, Ecological Attention of Government, and Regional Energy Intensity
The impact of Chinese-style fiscal decentralization on regional energy intensity has long been disputed by the supporters of “federal environmentalism” and those who hold “race to the bottom” views. At the same time, with the transformation of China’s development mode, the Chinese government is paying increasing attention to the protection of ecological civilization and the realization of sustainable development, and the government’s attention to the ecological environment is becoming an important factor affecting regional energy intensity. Therefore, this paper takes the fiscal decentralization and ecological attention of local governments in China as the research object and analyzes their impact mechanism on regional energy intensity. Firstly, the entropy weight method was used to measure the comprehensive score of fiscal decentralization of Chinese local governments, and the text analysis method was used to obtain the ecological attention index of Chinese provincial local governments, which was sorted into panel data of 30 provinces (municipalities and autonomous regions) in mainland China from 2007 to 2019. The spatial econometric model and panel threshold model are structured as the means for analyzing the impact that fiscal decentralization and the ecological attention of local governments have, respectively, on regional energy intensity targets. We obtained the following conclusions: Chinese fiscal decentralization can significantly improve the regional energy intensity, and the fiscal decentralization of a region can significantly reduce the energy intensity in nearby regions; the enhancement of ecological attention of local governments will significantly inhibit regional energy intensity, and also has a significant inhibitory effect on the energy intensity of neighboring regions. As the threshold variable—which is the ecological attention of local governments—increases and reaches a certain level, fiscal decentralization will significantly and reversely inhibit regional energy intensity, indicating that the ecological attention of local governments can moderate the distortion of fiscal decentralization with regards to regional energy efficiency
Chinese-Style Fiscal Decentralization, Ecological Attention of Government, and Regional Energy Intensity
The impact of Chinese-style fiscal decentralization on regional energy intensity has long been disputed by the supporters of “federal environmentalism” and those who hold “race to the bottom” views. At the same time, with the transformation of China’s development mode, the Chinese government is paying increasing attention to the protection of ecological civilization and the realization of sustainable development, and the government’s attention to the ecological environment is becoming an important factor affecting regional energy intensity. Therefore, this paper takes the fiscal decentralization and ecological attention of local governments in China as the research object and analyzes their impact mechanism on regional energy intensity. Firstly, the entropy weight method was used to measure the comprehensive score of fiscal decentralization of Chinese local governments, and the text analysis method was used to obtain the ecological attention index of Chinese provincial local governments, which was sorted into panel data of 30 provinces (municipalities and autonomous regions) in mainland China from 2007 to 2019. The spatial econometric model and panel threshold model are structured as the means for analyzing the impact that fiscal decentralization and the ecological attention of local governments have, respectively, on regional energy intensity targets. We obtained the following conclusions: Chinese fiscal decentralization can significantly improve the regional energy intensity, and the fiscal decentralization of a region can significantly reduce the energy intensity in nearby regions; the enhancement of ecological attention of local governments will significantly inhibit regional energy intensity, and also has a significant inhibitory effect on the energy intensity of neighboring regions. As the threshold variable—which is the ecological attention of local governments—increases and reaches a certain level, fiscal decentralization will significantly and reversely inhibit regional energy intensity, indicating that the ecological attention of local governments can moderate the distortion of fiscal decentralization with regards to regional energy efficiency
Amygdalin inhibits renal fibrosis in chronic kidney disease
Key Laboratory of Fujian Province [2008J1006]; Nanjing Medical Technology Innovation Project, China [2009MA093]Renal interstitial fibrosis is a common outcome of chronic renal diseases. Amygdalin is one of a number of nitrilosides, the natural cyanide-containing substances abundant in the seeds of plants of the prunasin family that are used to treat cancer and relieve pain. However, whether amygdalin inhibits the progression of renal fibrosis or not remains unknown. The present study aimed to assess the therapeutic posential of amygdalin by investigating its effect and potential mechanism on the activation of renal interstitial fibroblast cells and renal fibrosis in rat unilateral ureteral obstruction (UUO). Treatment of the cultured renal interstitial fibroblasts with amygdalin inhibited their proliferation and the production of transforming growth factor (TGF)-beta 1. In the rat model of obstructive nephropathy, following ureteral obstruction, the administration of amygdalin immediately eliminated the extracellular matrix accumulation and alleviated the renal injury on the 21st day. Collectively, amygdalin attenuated kidney fibroblast (KFB) activation and rat renal interstitial fibrosis. These results indicate that amygdalin is a potent antifibrotic agent that may have therapeutic potential for patients with fibrotic kidney diseases
Engineered Zymomonas mobilis tolerant to acetic acid and low pH via multiplex atmospheric and room temperature plasma mutagenesis
Abstract Background Cellulosic biofuels are sustainable compared to fossil fuels. However, inhibitors, such as acetic acid generated during lignocellulose pretreatment and hydrolysis, would significantly inhibit microbial fermentation efficiency. Microbial mutants able to tolerate high concentration of acetic acid are needed urgently to alleviate this inhibition. Results Zymomonas mobilis mutants AQ8-1 and AC8-9 with enhanced tolerance against acetic acid were generated via a multiplex atmospheric and room temperature plasma (mARTP) mutagenesis. The growth and ethanol productivity of AQ8-1 and AC8-9 were both improved in the presence of 5.0–8.0 g/L acetic acid. Ethanol yield reached 84% of theoretical value in the presence of 8.0 g/L acetic acid (~ pH 4.0). Furthermore, a mutant tolerant to pH 3.5, named PH1-29, was generated via the third round of ARTP mutagenesis. PH1-29 showed enhanced growth and ethanol production under both sterilized/unsterilized conditions at pH 4.0 or 3.5. Intracellular NAD levels revealed that mARTP mutants could modulate NADH/NAD+ ratio to respond to acetic acid and low pH stresses. Moreover, genomic re-sequencing revealed that eleven single nucleic variations (SNVs) were likely related to acetic acid and low pH tolerance. Most SNVs were targeted in regions between genes ZMO0952 and ZMO0956, ZMO0152 and ZMO0153, and ZMO0373 and ZMO0374. Conclusions The multiplex mutagenesis strategy mARTP was efficient for enhancing the tolerance in Z. mobilis. The ARTP mutants generated in this study could serve as potential cellulosic ethanol producers