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Article
Publication date: 6 November 2017

Yingyu Zhao, Zhenbin Chen, Jie Li, Zhen Liu, Donglei Liu and Zhizong Li

The purpose of the paper is to separate and purify flavonoids existed in Lamiophlomis rotata (Benth.) Kudo. by macroporous adsorption resin (MAR) mixed-bed technology.

116

Abstract

Purpose

The purpose of the paper is to separate and purify flavonoids existed in Lamiophlomis rotata (Benth.) Kudo. by macroporous adsorption resin (MAR) mixed-bed technology.

Design/methodology/approach

The adsorption and desorption parameters were characterized by UV-VIS spectrophotometry. The optimal MAR mixed bed was screened based on the adsorption experiments; the experiment process was investigated by the order of single, two and three MAR mixed bed separately; and the adsorption performance, which was composed by the authority of 80 per cent adsorption ratios and 20 per cent desorption ratios, was adopted to screen MAR mixed bed for flavonoids. The adsorption dynamic investigated the order of reaction first, and then the adsorption mechanism was researched further. The adsorption thermodynamic investigated the adsorption isotherm first, and then the adsorption feature was analyzed.

Findings

This research found that MAR mixed bed of LS-840 + LSD301 with mass ratio of mLS840:mLSD301 = 3:2 was the optimized combination, and the optimal conditions of the adsorption were volume V = 50 mL, time t = 6.5 h, T = 40°C. The desorption conditions were ethanol content = 70 per cent, desorption time t = 3.0 h, T = 40°C. The adsorption dynamic experimental data fitted better to the pseudo-second-order, and the intra-particle-diffusion model was more suitable for expression of the adsorption mechanism in mesopores process, whereas the homogeneous particle-diffusion model was more suitable in microspores. The adsorption was a physical and multilayer adsorption, and the adsorption driving force was disappeared as it transferred to the fourth layer.

Practical implications

Find an efficient way to separate flavonoids that useful for human’s health, which can not only utilize of plant resources effectively, but also make outstanding contributions to medical industry. It has very high economic and social value.

Originality/value

This contribution provided a new way to separate flavonoids from Lamiophlomis rotata (Benth.) Kudo. Under the optimal conditions, the adsorption rate (F) of MAR mixed bed LS-840 + LSD301 to the flavonoids was 97.81 per cent, the desorption rate (D) was 90.02 per cent and the purity of flavonoids was dramatically increased about 2.08 fold of the crude extract from 28 to 58.4 per cent, and the recovery yield of flavonoids arrived at 91.6 per cent after a circle of adsorption/desorption operation.

Details

Pigment & Resin Technology, vol. 46 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 December 2021

Hongyi Tu, Donglei Liu, Zhenbin Chen and Chunli Liu

Using a reversible addition fragmentation chain transfer reaction, a series of resins were prepared by using N, N-diethyl acrylamide (DEA), poly (ß-hydroxyethyl methacrylate…

86

Abstract

Purpose

Using a reversible addition fragmentation chain transfer reaction, a series of resins were prepared by using N, N-diethyl acrylamide (DEA), poly (ß-hydroxyethyl methacrylate) (PHEMA) as hydrophilic blocks and poly (glycidyl methacrylate) (PGMA) as hydrophobic blocks (and as a target for immobilizing penicillin G acylase [PGA]) and the low critical solution temperature (LCST) of which could be adjusted by changing the segment length of blocks.

Design/methodology/approach

To make the catalytic conversion temperature of immobilized PGA fallen into the temperature range of the sol state of thermosensitive block resin, a type of thermosensitive block resin, i.e. PDEA-b-PHEMA-b-PGMA (DHGs) was synthesized to immobilize PGA, and the effect of segment order of block resin was investigated on the performance of PGA.

Findings

Carrier prepared with monomers molar ratio of n(DEA) : n(HEMA): n(GMA) = 100: 49: 36 presented loading capacity (L) and enzyme activity recovery ratio (Ar) of 110 mg/g and 90%, respectively, and a block resin with LCST value of 33 °C was essential for keeping higher Ar of PGA.

Originality/value

PGA has become an important biocatalyst in modern chemistry industry. However, disadvantages include difficulty in separation, poor repeatability and high cost, which limits the scope of PGA applications. The effective method is to immobilize the enzyme to the carrier, which could overcome the disadvantage of free enzyme.

Details

Pigment & Resin Technology, vol. 51 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 2 May 2017

Yingyu Zhao, Zhenbin Chen, Donglei Liu, Jiapeng Long and Duolong Di

The purpose of this paper is to separate and purify flavonoids existing in the leaves of Sophora japonica by a novel method, macroporous adsorption resin (MAR) mixed-bed…

178

Abstract

Purpose

The purpose of this paper is to separate and purify flavonoids existing in the leaves of Sophora japonica by a novel method, macroporous adsorption resin (MAR) mixed-bed technology, and the optimal MAR mixed bed was screened based on the adsorption experimental result with the order of single, two, three and four MAR mixed bed separately.

Design/methodology/approach

The adsorption performance of MAR and MAR mixed bed for flavonoids was studied using ultraviolet – visible (UV-VIS) spectrophotometry.

Findings

This research showed that the MAR mixed bed of LZ-54 + LZ-67 with a mass ratio of mLZ-54:mLZ-67 = 1:1 was the optimized combination with the optimal conditions of adsorption (volume V = 140 mL, pH = 5, T = 35°C) and desorption (liquid ratio R = 50 per cent, T = 30°C, pH = 6) obtained, relatively.

Practical implications

This study aims to find an efficient way of separating flavonoids and other components that are useful for human health from Sophora japonica, which is complying with the policy of sustainable development.

Originality/value

This contribution provided a novel way to separate flavonoids from Sophora japonica. Under the optimal conditions, the adsorption rate (F) of MAR mixed bed LZ-54 + LZ-67 to the flavonoids was 63.65 per cent, the desorption rate (D) was 87.31 per cent and the purity was dramatically achieved at 58.17 per cent from 17.67 per cent after a round of adsorption/desorption operation.

Details

Pigment & Resin Technology, vol. 46 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 12 March 2019

Shiquan Wang, Guoyin Shang and Shuang Zhang

Concerning that limited explanation exists examining the function of corporate governance in trust processing within entrepreneurial network development, the purpose of this paper…

472

Abstract

Purpose

Concerning that limited explanation exists examining the function of corporate governance in trust processing within entrepreneurial network development, the purpose of this paper is to explore trust evolution and the role of corporate governance in an entrepreneurial network.

Design/methodology/approach

This paper makes an innovative exploration based on the case study of NVC Lighting Holding Limited.

Findings

It proposes that in the initial period of network relationship which is based on entrepreneur’s individual social network and embodies sole social network embeddness, entrepreneurial network relies more on affective trust than contractual trust. When stepping into extending period of network relationship which reflects separate embeddedness of social and market network, however, entrepreneurial network has an equal reliance on both affective trust and contractual trust. With further development, when ushering in the phase of maturity which undergoes superimposing embeddedness of both social and market network, entrepreneur network inclines to rely more heavily on affective trust than contractual trust. During the whole process, it can be found that the reliance of entrepreneurial network on trust has the tendency to transfer from affective trust to contractual trust. Furthermore, decreasing of equity ratio of founders and strengthening of controlling right heterogeneity in the corporate governance have facilitated the transfer process and the entrepreneurs’ authority has restraining effect on the evolution of the process.

Originality/value

Through case study, this paper presents the trust evolution process in different stages of entrepreneurial network. Another important theoretic contribution of this paper is that it reveals the function of corporate governance in trust processing within entrepreneurial network development.

Details

Chinese Management Studies, vol. 13 no. 4
Type: Research Article
ISSN: 1750-614X

Keywords

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Article
Publication date: 7 November 2016

Weian Li and Pengcheng Wang

Philanthropy is taken as a strategic behavior by private enterprises to obtain financial resources from governments. This paper aims to examine the relationship between private…

789

Abstract

Purpose

Philanthropy is taken as a strategic behavior by private enterprises to obtain financial resources from governments. This paper aims to examine the relationship between private enterprise philanthropy and the debt finance, further investigating the way by which governments exchange resources with private enterprises.

Design/methodology/approach

The paper opted for an empirical study using a sample of 1,489 Chinese private-listed companies from 2007 to 2010. The study analyzed the relationship between philanthropy and debt finance based on the resource dependence theory and social exchange theory and tested the moderating effect of political connection.

Findings

Philanthropy can help private enterprises to get the debt finance, and this effect occurs mainly among the political connected private enterprises; the higher degree of credit allocation marketization is, the less philanthropy can affect the debt finance and the less influence political connection can exert on that relationship. Philanthropy contributes to debt financing mainly because it can help obtain more long-term loan, and this effect is more obvious for politically connected private enterprises in regulated industries.

Originality/value

This paper verifies the action logic of private enterprises philanthropy from the perspective of exchange behavior, which is helpful to understand the motive and influence of private enterprises philanthropy.

Details

Nankai Business Review International, vol. 7 no. 4
Type: Research Article
ISSN: 2040-8749

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