Sugarcane rind contains some functional phenolic acids. The separation of these compounds from sugarcane rind is able to realize the integrated utilization of the crop and reduce environment pollution. In this paper, a novel protocol based on interfacing online solid-phase extraction with high-speed counter-current chromatography (HSCCC) was established, aiming at improving and simplifying the process of phenolic acids separation from sugarcane rind. The conditions of online solid-phase extraction with HSCCC involving solvent system, flow rate of mobile phase as well as saturated extent of absorption of solid-phase extraction were optimized to improve extraction efficiency and reduce separation time. The separation of phenolic acids was performed with a two-phase solvent system composed of butanol/acetic acid/water at a volume ratio of 4:1:5, and the developed online solid-phase extraction with HSCCC method was validated and successfully applied for sugarcane rind, and three phenolic acids including 6.73 mg of gallic acid, 10.85 mg of p-coumaric acid, and 2.78 mg of ferulic acid with purities of 60.2, 95.4, and 84%, respectively, were obtained from 150 mg sugarcane rind crude extracts. In addition, the three different elution methods of phenolic acids purification including HSCCC, elution-extrusion counter-current chromatography and back-extrusion counter-current chromatography were compared.

The volatile oil of Mentha haplocalyx is widely used in medicine, food, and cosmetics. However, a large amount of its residue after steam extraction of volatile oil is abandoned, resulting in a waste of resources. The method of aqueous twophase flotation coupled with preparative high-performance liquid chromatography was established for the separation and purification of nonvolatile active compounds from Mentha haplocalyx for the first time. The parameters of the twophase aqueous flotation were optimized. Under the optimal conditions including flotation solvent PEG 1000 aqueous solution (1:1, w/w), pH 5, (NH 4 ) 2 SO 4 concentration of 350 g/L in aqueous phase, N 2 flow rate of 20 mL/min, and flotation time of 20 min, the flotation efficiency of linarin, hesperidin, and didymin was 82.24, 76.38, and 89.33%, respectively. The linarin and hesperidin with the high purities of 95.8 and 97.2%, respectively, were obtained by using preparative high performance liquid chromatography. The neuroprotective effect of linarin against H 2 O 2 -induced oxidative stress in rat hippocampal neurons was investigated. The experimental result indicated that linarin could alleviate H 2 O 2 -induced oxidative stress. The work indicated that the combination of aqueous two-phase flotation and preparative high performance liquid chromatography is a feasible and practical method for the purification of nonvolatile active substances from Mentha haplocalyx, which would provide a reference process for the comprehensive utilization of M. haplocalyx. Especially, linarin might be used as a good source of natural neuroprotectants.

In this work, a general and novel separation technique gas-assisted three-liquid-phase extraction was established and applied in separating and concentrating isoflavonoids from the actual sample of puerariae extract by one step. For the gas-assisted threeliquid-phase extraction method, optimal conditions were selected: polyethylene glycol 2000 and ethyl acetate as the flotation solvent, pH 5, (NH 4 ) 2 SO 4 concentration 350 g/L in aqueous phase, N 2 flow rate 30 mL/min, flotation time 50 min, and flotation twice. Five isoflavonoids compounds puerarin, 3′-methoxydaidzin, puerarinxyloside, daidzin and daidzein were separated with recoveries of 82, 84, 80, 88 and 89%, respectively. The separated products were purified by preparative high-performance liquid chromatography, and the purity of the final products was >96%. The established general gas-assisted three-liquid-phase extraction was used to separate anthraquinones from Cassiae Semen under the optimal conditions, and the recoveries were >75%. The experimental results showed that the established gas-assisted three-liquid-phase extraction method is a general technique for separating active compounds from herb extract.

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This paper takes A-share listed companies from 2008 to 2018 as samples, and discusses the relationship between bank background CEO and enterprise short-term loan and long-term investment. It is found that the CEO with banking background can significantly inhibit the short-term loan and long-term investment of enterprises. Compared with the highly market-oriented regions and state-owned enterprises, the CEO with banking background has a more obvious inhibitory effect on short-term loan and long-term investment of enterprises. In this paper additionally, PSM, lag variable and Heckman two-stage model are used for robustness test, and the above conclusions are still valid.