Pingkang Qian,Kun Gao,Zheng Gao,Chunye Xue,Xiaoli Hu,Qiaoqiao Liu,Jingwei Dong,Xiangyuan Deng
The aim of this work was to investigate the effects of myo -inositol (MI) on growth, photosynthetic activity , and chemical compositions of Chlorella sorokiniana . Results showed that a maximum value of cell density was obtained when this alga was cultivated in BG11 media with 1000 mg L −1 MI, which was 1.37 times greater than that in the controls. Moreover, it was observed that MI had a negative effect on algal photosynthetic activity, which could be alleviated by regulating the contents of chemical compositions, such as chlorophyll a (Chl a ). In the BG11 media with MI, contents of Chl a in the algal cells were in the range of 0.30–0.35 μg 10 −6 cells, which were about 1.75 times greater than that in the controls during microalgae cultivation. The accumulated Chl a would be used to capture and deliver more photons during algal photosynthesis . In addition, contents of lipids , carbohydrates, and proteins varied with the changes in MI concentrations. Thus, it is concluded that MI could promote the algal growth and play an important role in regulating the biochemical compositions in algal cells. These data would provide basic theory and technical support for large-scale cultivation and biomass production of microalgae by adding MI to culture media.
Haoting Yin,Dongyuan Ye,Tianyu Wu,Xiaoyu Meng,Hai-Mu Ye
The sluggish crystallization kinetics of poly(ethylene succinate) (PES), a biodegradable aliphatic polyester with promising mechanical properties, severely restricts its industrial processing and application. To address this limitation, this study introduces two bio-derived hexahydric alcohols, myo -inositol (MIS) and dipentaerythritol (DPE), as nucleating agents to regulate PES crystallization. Non-isothermal and isothermal differential scanning calorimetry, polarized optical microscopy, and wide angle X-ray diffraction analyses reveal that both MIS and DPE significantly enhance nucleation density and crystallization rates via epitaxial templating and hydrogen-bonding interactions. DPE outperforms MIS, achieving 19.1 °C increase in crystallization temperature and 28% improvement in relative crystallinity at 2 wt% loading, attributed to its superior epitaxial surface provision and stronger intermolecular interactions for PES chains. Fourier transform infrared spectroscopy further confirms the plasticizing effect of these agents, which reduces rigid amorphous fractions and enhances chain mobility. The synergistic mechanism combines heterogeneous epitaxial nucleation and chain lubrication, enabling accelerated crystallization kinetics without compromising biodegradability. This work provides a sustainable strategy to optimize PES processing efficiency and performance, advancing its potential as a viable alternative to conventional thermoplastics.
Haotian Cheng,Yuan Li,Yi Zhou,Shuke Wu,Yi-Heng P. Job Zhang
Cellobiose phosphorylase (CBP) catalyzes the reversible phosphorolysis of cellobiose to glucose and α-D-glucose-1-phosphate. CBPs play an important role in the in vivo enzymatic utilization of cellulosic materials. Here we discovered a novel CBP from Thermoclostridium caenicola (TcCBP), displaying 50–75 % sequence homology with previously reported CBPs. Recombinant TcCBP was well expressed in E. coli BL21(DE3), with a 1.6-fold increase in soluble expression levels over the widely-used Clostridium thermocellum CBP (CtCBP). This enzyme exhibited broad pH adaptability, maintaining substantial activities across pH 4.0–7.5 in the synthetic direction and pH 5.0–7.5 in the phosphorolytic direction. Compared to CtCBP, TcCBP displayed the superior thermostability and a nearly 100-fold improvement in "Product-to-Enzyme Ratio" (PE value). The biosynthesis of myo -inositol from cellobiose was conducted by using this CBP along with other four thermophilic enzymes (i.e., phosphoglucomutase, inositol 1-phosphate synthase, inositol monophosphatase, and polyphosphate glucokinase) in one pot without step-by-step addition of enzymes. Approximately 96 mM of myo -inositol was produced from 50 mM of cellobiose. These results indicated that this enzyme could be a potential thermophilic enzyme used for the production of value-added biochemicals by in vitro BioTransformation.
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