Melanin involves in various biological functions, widely used in cosmetic, pharmacology medicine and other fields. However, melanin application is limited due to low productivity and high cost. In this work, melanin e...Melanin involves in various biological functions, widely used in cosmetic, pharmacology medicine and other fields. However, melanin application is limited due to low productivity and high cost. In this work, melanin extraction method from rapeseed meal(RSM) was explored. Effects of hydrochloric acid(HCl) concentration, ethanol concentration, extraction temperature and time, and solid-liquid ratio were evaluated systematically. According to results of single factor experiment and Box-Behnken experiment, the optimum extraction conditions of melanin from RSM were as follows: HCl concentration, 0.5 mol/L; ethanol concentration, 70%; extraction temperature, 40 o C; extraction time, 1 h; solid liquid ratio, 1/4 g/mL. Under these conditions, extraction yields of crude melanin(CM) and purified melanin(PM) were 9.00% and 1.44%, respectively. Compared with synthetic melanin(SM) from Sigma, the relative purities of CM and PM were 7.82% and 29.57%, respectively. Moreover, feedstuff value of RSM residue was also improved after melanin isolation by significantly reducing glucosinolate content.展开更多
Meituan Waimai,which was officially launched in November 2013,has created a huge market for food delivery in China.After years of development,China’s online food delivery market reached RMB 664.62 billion in 2020.In ...Meituan Waimai,which was officially launched in November 2013,has created a huge market for food delivery in China.After years of development,China’s online food delivery market reached RMB 664.62 billion in 2020.In 2022,Meituan Waimai and Ele.me,two food delivery platforms,have created a duopoly in China’s food delivery industry.Due to the success of the food delivery industry,a significant amount of food delivery packaging waste has caused far-reaching harm.This literature review primarily organizes the research on the impact of online food delivery packaging from the perspective of environmental protection.It uses the criterion layer index of online food delivery waste management ecosystem to analyze the impact of the government,environmental non-governmental organizations(NGOs),garbage recycling processors,consumers,online food delivery platforms,takeaway merchants,and takeaway packaging manufacturers.The review shows that scholars generally believe that takeaway waste management is a complex process involving multiple factors.The implementation of policies at the government level is inadequate,and studies at the environmental NGO level are scant.At the consumer level,more environmental awareness education is required.Online food delivery platforms and takeaway merchants should assume greater corporate social responsibility,and manufacturers of takeaway packaging need prioritize the substitution of environmentally friendly materials.There is a consensus that paper-made and recyclable packaging boxes are more environmentally friendly than degradable packaging,which is not as environmentally friendly as is commonly believed.The academia and the industry have conducted various studies and pilot projects on recyclable packaging.If all levels cooperate well,this will be an effective way to manage takeaway packaging garbage.At last,we propose the following assumptions for future research:Besides environmental hazards,takeaway garbage has caused direct or indirect physical harm to humans and animals.Increasing consumer awareness may increase their propensity to participate in governance.Additionally,existing food delivery platforms may need to improve their corporate social responsibility awareness to provide environmentally conscious consumers with sufficient and effective plastic reduction guidance measures during the ordering process.Moreover,will biodegradable plastic products face the same ironic situation as biofuels?That is,the initial intention of technology development is to improve the environment,but the actual process of production or processing may controversially aggravate the environment.展开更多
基金supported by Ministry of Science and Technology of the People’s Republic of China (2016YFD0501209)Chinese Academy of Agricultural Sciences (CAAS-ASTIP-2013-OCRI)
文摘Melanin involves in various biological functions, widely used in cosmetic, pharmacology medicine and other fields. However, melanin application is limited due to low productivity and high cost. In this work, melanin extraction method from rapeseed meal(RSM) was explored. Effects of hydrochloric acid(HCl) concentration, ethanol concentration, extraction temperature and time, and solid-liquid ratio were evaluated systematically. According to results of single factor experiment and Box-Behnken experiment, the optimum extraction conditions of melanin from RSM were as follows: HCl concentration, 0.5 mol/L; ethanol concentration, 70%; extraction temperature, 40 o C; extraction time, 1 h; solid liquid ratio, 1/4 g/mL. Under these conditions, extraction yields of crude melanin(CM) and purified melanin(PM) were 9.00% and 1.44%, respectively. Compared with synthetic melanin(SM) from Sigma, the relative purities of CM and PM were 7.82% and 29.57%, respectively. Moreover, feedstuff value of RSM residue was also improved after melanin isolation by significantly reducing glucosinolate content.
文摘Meituan Waimai,which was officially launched in November 2013,has created a huge market for food delivery in China.After years of development,China’s online food delivery market reached RMB 664.62 billion in 2020.In 2022,Meituan Waimai and Ele.me,two food delivery platforms,have created a duopoly in China’s food delivery industry.Due to the success of the food delivery industry,a significant amount of food delivery packaging waste has caused far-reaching harm.This literature review primarily organizes the research on the impact of online food delivery packaging from the perspective of environmental protection.It uses the criterion layer index of online food delivery waste management ecosystem to analyze the impact of the government,environmental non-governmental organizations(NGOs),garbage recycling processors,consumers,online food delivery platforms,takeaway merchants,and takeaway packaging manufacturers.The review shows that scholars generally believe that takeaway waste management is a complex process involving multiple factors.The implementation of policies at the government level is inadequate,and studies at the environmental NGO level are scant.At the consumer level,more environmental awareness education is required.Online food delivery platforms and takeaway merchants should assume greater corporate social responsibility,and manufacturers of takeaway packaging need prioritize the substitution of environmentally friendly materials.There is a consensus that paper-made and recyclable packaging boxes are more environmentally friendly than degradable packaging,which is not as environmentally friendly as is commonly believed.The academia and the industry have conducted various studies and pilot projects on recyclable packaging.If all levels cooperate well,this will be an effective way to manage takeaway packaging garbage.At last,we propose the following assumptions for future research:Besides environmental hazards,takeaway garbage has caused direct or indirect physical harm to humans and animals.Increasing consumer awareness may increase their propensity to participate in governance.Additionally,existing food delivery platforms may need to improve their corporate social responsibility awareness to provide environmentally conscious consumers with sufficient and effective plastic reduction guidance measures during the ordering process.Moreover,will biodegradable plastic products face the same ironic situation as biofuels?That is,the initial intention of technology development is to improve the environment,but the actual process of production or processing may controversially aggravate the environment.
