Co-fermentation of kitchen waste and excess sludge for organic acid production: a review / 生物工程学报

Resource utilization is an effective way to cope with the rapid increase of kitchen waste and excess sludge, and volatile fatty acids produced by anaerobic fermentation is an important way of recycling organic waste. However, the single substrate limits the efficient production of volatile fatty acids. In recent years, volatile fatty acids produced by anaerobic co-fermentation using different substrates has been widely studied and applied. In this paper, we analyze the characteristics of fermentation to produce acid using kitchen waste and excess sludge alone or mixture. Influences of environmental factors and microbial community structure on the type and yield of volatile fatty acids in the anaerobic fermentation system are discussed in detail. Moreover, we propose future research directions, to provide a reference for recycling kitchen waste and excess sludge.

Advances in heterotrophic nitrification-aerobic denitrifying bacteria for nitrogen removal under extreme conditions / 生物工程学报

Heterotrophic nitrification-aerobic denitrification (HN-AD) is an enrichment and breakthrough theory of traditional autotrophic nitrification heterotrophic denitrification. Heterotrophic nitrification-aerobic denitrifiers with the feature of wide distribution, strong adaptability and unique metabolic mechanism have many special advantages, including fast-growing, rapid biodegradability and long lasting activity, which can rapidly remove ammonia nitrogen, nitrate nitrogen (NO₃⁻-N) and nitrite nitrogen (NO₂⁻-N) under aerobic conditions simultaneously. Therefore, HN-AD bacteria show the important potential for denitrification under extreme conditions with high-salt, low-temperature or high-ammonia nitrogen environment, and HN-AD bacteria attract extensive attention in the field of biological denitrification of wastewater. In this review, we first introduce the previously reported HN-AD bacterial species which have denitrification performance in the extreme environments and state their typical metabolic mechanism. Then, we systematically analyze the nitrogen removal characteristics and potential under extreme conditions. We also briefly describe the progress in the application of HN-AD bacterial. Finally, we outlook the application prospects and research directions of HN-AD denitrification technology.

Advances in Researches on Metabolic Mechanism and Toxicity of Phthalate Esters / 环境与健康杂志

Phthalate esters widely exist in the environment. It has been demonstrated that they are harmful to human bodies. Phthalate mono-esters are the first metabolite of phthalate esters. In general,biotransformation or metabolism of xenobiotics most frequently result in detoxification of the chemical and facilitates excretion from the body. However,this may not be the case for phthalates. In the present paper,metabolism of phthalate esters and the toxicity of the phthalate mono-esters were reviewed,not only the effect of their mutagenesis,teratogenesis and carcinogenesis,but also their toxicity on reproduction,development,hormones,nuclear receptor,inflammation and obesity were included.

Review on Metabolic Mechanism of Glycogen-accumulating Organisms in Biological Phosphorus Removal System / 微生物学通报

Enhanced biological phosphorus removal (EBPR) is widely accepted as one of the most economical and sustainable processes to remove phosphorus from wastewater.Poor performance or complete failure of EBPR processes has been substantially reported because of the proliferation of glycogen-accumulating organisms (GAOs) in the system.This paper presented the GAOs' metabolic mechanism and the impact factors, such as influent substrate, P/C ratio, pH value, temperature and SRT, on competition between GAOs and PAOs to better understand GAOs' characteristics and improve the performance and reliability of EBPR systems.