Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical ...Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical properties has yet to be explored.In this study,we report on the fabrication of intrinsically super-strong fluorescent silk by feeding Bombyx mori silkworm carbon nanodots(CNDs).The CNDs were incorporated into silk fibroin,hindering the conformation transformation,confining crystallization,and inducing orientation of mesophase.The resultant silk exhibited super-strong mechanical properties with breaking strength of 521.9±82.7 MPa and breaking elongation of 19.2±4.3%,improvements of 55.1%and 53.6%,respectively,in comparison with regular silk.The CNDs-reinforced silk displayed intrinsic blue fluorescence when exposed to 405 nm laser and exhibited no cytotoxic effect on cells,suggesting that multi-functional silks would be potentially useful in bioimaging and other applications.展开更多
Aims Anthocyanin accumulation is the main factor underlying why young plant leaves turn red,and plant growth follows the principle of maximizing the economic efficiency of energy.There is a need to verify the role of ...Aims Anthocyanin accumulation is the main factor underlying why young plant leaves turn red,and plant growth follows the principle of maximizing the economic efficiency of energy.There is a need to verify the role of young plant leaves turning red and confirm whether anthocyanin accumulation overconsumes the energy of the plant.Methods We compared the different pigment contents,antioxidant capaci-ties,leaf mass per area,photosynthetic characteristics,dark res-piration rates,light compensation points(LCPs)and electron flow distribution of young and mature Schima superba leaves grown under full sunlight and 30%full sunlight conditions.We then exam-ined the correlations between anthocyanins and total antioxidant capacity,photosynthetic pigments,dark respiration rates,LCPs by using linear regression.Finally,we analyzed Pearson correlation coefficients and used principal component analysis to evaluate the interactions of these functional indicators.Important Findings The young leaves of S.superba accumulated anthocyanins in full sunlight but not in 30%full sunlight.Anthocyanins substantially con-tributed to the total antioxidant capacity(accounting for 33.29%)in juvenile S.superba leaves.Young leaves containing more anthocyanin accumulated less reactive oxygen species after high light(HL)treat-ment.However,juvenile leaves accumulating anthocyanins showed 56.97%higher dark respiration rates,24.79%higher LCPs and 5.32%higher allocations of electron flow to photorespiration and lower organic substance accumulation than did those without anthocyanins.These results suggest that young S.superba leaves must consume more energy to accumulate anthocyanins to adapt to HL environments.Therefore,plants sacrifice growth rate to ensure survival,which is a trade-off for their ability to respond to external environments.展开更多
基金sponsored by the National Key Research and Development Program of China(2016YFA0201700,2016YFA0201702)the Fundamental Research Funds for the Central Universities(2232019A3-06,2232019D3-02)+2 种基金the National Key Research and Development Program of China(2018YFC1105800)the National Natural Science Foundation of China(21674018,51903045)the Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-Dimension Materials(18520750400).
文摘Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical properties has yet to be explored.In this study,we report on the fabrication of intrinsically super-strong fluorescent silk by feeding Bombyx mori silkworm carbon nanodots(CNDs).The CNDs were incorporated into silk fibroin,hindering the conformation transformation,confining crystallization,and inducing orientation of mesophase.The resultant silk exhibited super-strong mechanical properties with breaking strength of 521.9±82.7 MPa and breaking elongation of 19.2±4.3%,improvements of 55.1%and 53.6%,respectively,in comparison with regular silk.The CNDs-reinforced silk displayed intrinsic blue fluorescence when exposed to 405 nm laser and exhibited no cytotoxic effect on cells,suggesting that multi-functional silks would be potentially useful in bioimaging and other applications.
基金This work was funded by the National Natural Science Foundation of China(31570398)The study was also sup-ported by Guangdong Province Natural Science Foundation(2017A030313167,2015A030311023).Conflict of interest statement.None declared.
文摘Aims Anthocyanin accumulation is the main factor underlying why young plant leaves turn red,and plant growth follows the principle of maximizing the economic efficiency of energy.There is a need to verify the role of young plant leaves turning red and confirm whether anthocyanin accumulation overconsumes the energy of the plant.Methods We compared the different pigment contents,antioxidant capaci-ties,leaf mass per area,photosynthetic characteristics,dark res-piration rates,light compensation points(LCPs)and electron flow distribution of young and mature Schima superba leaves grown under full sunlight and 30%full sunlight conditions.We then exam-ined the correlations between anthocyanins and total antioxidant capacity,photosynthetic pigments,dark respiration rates,LCPs by using linear regression.Finally,we analyzed Pearson correlation coefficients and used principal component analysis to evaluate the interactions of these functional indicators.Important Findings The young leaves of S.superba accumulated anthocyanins in full sunlight but not in 30%full sunlight.Anthocyanins substantially con-tributed to the total antioxidant capacity(accounting for 33.29%)in juvenile S.superba leaves.Young leaves containing more anthocyanin accumulated less reactive oxygen species after high light(HL)treat-ment.However,juvenile leaves accumulating anthocyanins showed 56.97%higher dark respiration rates,24.79%higher LCPs and 5.32%higher allocations of electron flow to photorespiration and lower organic substance accumulation than did those without anthocyanins.These results suggest that young S.superba leaves must consume more energy to accumulate anthocyanins to adapt to HL environments.Therefore,plants sacrifice growth rate to ensure survival,which is a trade-off for their ability to respond to external environments.
