Improving the electrochemical characteristics and performance of a neutral all-iron flow battery by using the iron reduction bacteria.

At present, the all-iron redox flow batteries (RFBs) have greater application potential due to high accessibility of electrolytes compared to traditional RFBs. Meanwhile, although electroactive bacteria can accelerate the electrons transfer, their potential to improve the performance of RFBs has been overlooked. Previously, we had confirmed that ferrous-oxidizing bacteria (FeOB) could enhance the performance of an all-iron RFB, therefore we conducted several batch experiments and chronopotentiometry experiments by using the ferric-reducing bacteria (FeRB) or mixed culture (FeOB and FeRB) to demonstrate whether they have the same or stronger effects on Fe3+-DTPA/Na4[Fe(CN)6] RFB. The results showed that the experimental reactors could achieve higher charging current density and initial cathodic potential during constant voltage charging process. The electrochemical impedance spectroscopy data and cyclic voltammetry curves demonstrated that the polarization impedance increased slower and reduction peak potential of experimental groups also emerged a positive shift compared to CK. According to chronopotentiometry experiments results, the microbes could function at maximum 0.3 M, 12 mA/cm2, and also improved the charging specific capacity. Combined the SEM pictures and microbial composition analysis, the main functional electroactive FeRB were Alcaligenes, Corynebacterium and Bacillus, which indicated to have important potential in improving the performance of RFBs.

Using ferrous-oxidizing bacteria to enhance the performance of a pH neutral all-iron flow battery.

Among various redox flow batteries (RFBs), the all-iron RFBs have greater application potential due to high accessibility of electrolytes. However, the potential of microaerobic ferrous-oxidizing bacteria (FeOB) to improve the performance of RFB has been neglected. Here, several experiments were conducted using Fe2+-diethylenetriaminepentaacetic acid (DTPA)/Na3[Fe(CN)6] as a redox couple for investigating the enhanced performance by FeOB in this RFB. Results showed that the maximum current density of experimental reactors could achieve 22.56 A/m2 at 0.1 M, whereas power density could still maintain 3.42 W/m2(16.96 A/m2 and 1.58 W/m2 for control group); meantime, the polarization impedance of anode increased slower and Fe2+-DTPA oxidation peak emerged maximum 494 mV negative shift. With increased electrolyte concentration in chronopotentiometry experiments, the experimental reactor achieved higher discharging specific capacity at 0.3 M, 10 mA/cm2. Microbial composition analysis showed maximum 75% is Brucella, indicating Brucella has ferrous-oxidizing electroactivity.

Polysaccharides as antioxidants and prooxidants in managing the double-edged sword of reactive oxygen species.

Polysaccharides, a class of naturally occurring carbohydrates, were widely presented in animals, plants, and microorganisms. Recently, health benefits of polysaccharides have attracted much attention due to their unique characteristics in reactive oxygen species (ROS) management. ROS, by-products of aerobic metabolism linked to food consumption, exhibited a dual role in protecting cells and fostering pathogenesis collectively termed double-edged sword. Some interesting studies reported that polysaccharides could behave as prooxidants under certain conditions, besides antioxidant capacities. Potentiation of the bright side of ROS could contribute to the host defense that was vitally important for the polysaccharides acting as biological response modifiers. Correspondingly, disease prevention of polysaccharides linked to the management of ROS production was systematically described and discussed in this review. Furthermore, major challenges and future prospects were presented, aiming to provide new insight into applying polysaccharides as functional food ingredients and medicine.

Physical activity level and incident type 2 diabetes among Chinese adults.

PURPOSE: The objective is to examine the association between physical activity level (PAL) and incident type 2 diabetes among middle-age and older Chinese men and women in urban China. METHODS: This prospective study included 6348 participants (age 35 to 74 yr) who were free of diabetes and cardiovascular disease at baseline. PAL was estimated on the basis of self-reported overall physical activity on a typical day. According to PAL, participants were classified into four groups: sedentary (PAL, 1.00-1.39), low active (PAL, 1.40-1.59), active (PAL, 1.60-1.89), and very active (PAL, >1.89). The association of PAL with incident diabetes was examined by Cox proportional hazards model. RESULTS: During 7.9 yr of follow-up (50,293 person-years), 478 incident cases of type 2 diabetes were identified. After adjustment for age, sex, geographic region, educational level, smoking, alcohol use, and family history of diabetes, the HR (95% CI) values for type 2 diabetes across increasing categories of PAL were 1.00 (reference), 0.82 (0.62-1.09), 0.63 (0.47-0.83), and 0.47 (0.36-0.61), respectively (P for trend <0.0001). Additional adjustment for baseline body mass index or waist circumference attenuated the magnitude of risk reduction, but it remained significant. The inverse association between PAL and risk of incident diabetes was persistent in subgroup analyses according to age, sex, hypertension, smoking, body mass index, waist circumference, and fasting plasma glucose level. CONCLUSIONS: Higher PAL is associated with substantial reduction in risk of type 2 diabetes. Our findings suggest the importance of a physically active lifestyle in the prevention of diabetes.