HPTLC-Bioluminescent Bioautography Screening of Herbal Teas for Adulteration with Hypolipidemic Drugs.

Teas based on nutraceutical herbs are an effective tool against hyperlipidemia. However, the adulteration with chemical drugs is frequently detected. By coupling bioluminescent bioautography with high performance thin-layer chromatography (HPTLC), we developed a facile method suitable for screening hypolipidemic drugs (ciprofibrate and bezafibrate) adulteration in five different herbal teas (lotus leaf, Apocynum, Ginkgo biloba, Gynostemia and chrysanthemum). First, the sensitivity of a bioluminescent bacteria to the analyte was evaluated on different HPTLC layer materials, revealing that the best performance was achieved on the silica gel layer. On this basis, sample extracts were separated on silica gel plates via a standardized HPTLC procedure, forming a selective detection window for the targeted compound. Then, the separation results were rapidly visualized by the bioluminescence inhibition of bacteria cells within 6 min after dipping. The observed inhibition displayed an acceptable limit of detection (<20 ng/zone or 2 mg/kg) and linearity (R2 ≥ 0.9279) within a wide concentration range (50-1000 ng/zone). Furthermore, the optimized method was performed with artificially adulterated samples and the recovery rates were determined to be within the range of 71% to 91%, bracing its practical reliability. Showing superiorly high simplicity, throughput and specificity, this work demonstrated that the analytical method jointly based on HPTLC and bioautography was an ideal tool for screening bioactive compounds in complex biological matrix.

A Simple and Standardized Method for the Determination of Total Solanesol in Potato Leaves and Its Extracts Based on HPLC-MS.

BACKGROUND: Solanesol is an important pharmaceutical intermediate raw material, mainly used to synthesize coenzyme Q10, vitamin K2. It can be found prominent in potato stems and leaves. But now potato stems and leaves are always abandoned or discarded as they are not suitable for use as feed in aquaculture or other purposes. These agricultural waste resources can be reutilized as the corresponding extracts. OBJECTIVE: To develop a simple and standardized method for the detection of total solanesol in potato leaves and its extracts. METHODS: N-hexane was chosen as the extraction solvent for three times in the solanesol extraction from potato leaves. HPLC-MS was used for the detection. RESULTS: The LOQ was 0.3 µg/g and the linear range was from 0.1 to 50 µg/mL. The precision and stability were evaluated by the relative standard deviations (RSDs) of three samples (potato leaves, Extract-1, Extract-2) for interday and intraday. The accuracy of the method was evaluated by the recoveries of three different spiked concentrations of solanesol for three samples, and results showed it ranged from 80.7% to 99.0% with RSDs less than 8.7%. CONCLUSIONS: The method we established can provide a simple and standardized way for the extraction and detection of total solanesol. HIGHLIGHTS: The work laid a foundation for the resource reutilization of potato stem and leaf.

[Isolation and preparation of polyphenols from grape seed by high-speed counter-current chromatography combined with preparative high performance liquid chromatography].

Eight polyphenols were separated from grape seed by high-speed counter-current chromatography (HSCCC). The separation was performed using a two-phase solvent system composed of 1-butanol-ethyl-water (1:14:15, v/v/v) and n-hexane-ethyl-water (1:10:10, v/v/v). The upper and lower phases were used as the stationary and mobile phases, respectively. A flow rate of 2.0 mL/min was employed for the separation. The apparatus was rotated at 900 r/min, and the detection wavelength was set at 280 nm. Under the selected conditions, procyanidins B1, procyanidins B2, gallic acid, epicatechin gallate, and catechin were obtained from the grape seed extracts with a purity of 98.5%, 97.2%, 98.3%, 98.9%, and 96.7%, respectively. Epicatechin, epicatechin gallate, and gallocatechin gallate were obtained by preparative high performance liquid chromatography with the purity of 99.2%, 99.3%, and 99.2%, respectively. The proposed method is simple and shows high separation efficiency, and will be of great importance for the comprehensive utilization of grape seed.

A general gas-assisted three-liquid-phase extraction method for separation and concentration of puerarin, 3'-methoxydaidzin, puerarinxyloside, daidzin and daidzein from puerariae extract.

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 three-liquid-phase extraction method, optimal conditions were selected: polyethylene glycol 2000 and ethyl acetate as the flotation solvent, pH 5, (NH4 )2 SO4 concentration 350 g/L in aqueous phase, N2 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.

Isolation and purification of alkaloids from lotus leaves by ionic-liquid-modified high-speed countercurrent chromatography.

An effective high-speed countercurrent chromatography method was successfully established by using ionic liquids as the modifier of the two-phase solvent system. Adding a small amount of ionic liquids significantly shortens the separation time and improves the separation efficiency. The conditions of ionic-liquid-modified high-speed countercurrent chromatography including solvent systems, types and content of added ionic liquids, and ionic liquids posttreatment were investigated. The established method was successfully applied to separate alkaloids from lotus leaves using a two-phase solvent system composed of petroleum ether/ethyl acetate/methanol/water/[C4 mim][BF4 ] (1:5:1:5:0.15, v/v/v/v/v). Four alkaloids pronuciferine (1.7 mg), N-nornuciferine (4.3 mg), nuciferine (3.1 mg), and roemerine (2.1 mg) were obtained with the purities of 90.53, 92.25, 99.86, and 98.63%, respectively, from 100 mg crude extract of lotus leaves. The results indicated that the ionic-liquid-modified high-speed countercurrent chromatography method was suitable for alkaloid separation from lotus leaves and would be a promising method for the separation of alkaloids from other natural products.

[Comparative analysis on industrial standardization degree of Chinese and Korean ginseng].

Panax ginseng is a well-known medicinal plant all over the world. It has high nutritional value and medicinal value. China and South Korea are the major countries in the world for ginseng cultivation, production and exportation. China's ginseng production accounts for more than half of the world, but the output value is less than that of Korea. The standardization process of ginseng industry plays an important role. This paper makes a detailed analysis of the Chinese and Korean ginseng national standards and the standardization process, and makes a detailed comparative analysis of the categories, standard contents, index selection, age, implementation and promotion status of the Chinese and Korean ginseng standards. The development disadvantages of ginseng industry standardization were displayed. And we give our advises on the standard revision, implementation of China's ginseng industry standardization, hoping to enhance the competitiveness of China's ginseng industry.

Separation of phenolic acids from sugarcane rind by online solid-phase extraction with high-speed counter-current chromatography.

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.

Separation of four flavonol glycosides from Solanum rostratum Dunal using aqueous two-phase flotation followed by preparative high-performance liquid chromatography.

Aqueous two-phase flotation followed by preparative high-performance liquid chromatography was used to separate four flavonol glycosides from Solanum rostratum Dunal. In the aqueous two-phase flotation section, the effects of sublation solvent, solution pH, (NH4 )2 SO4 concentration in aqueous solution, cosolvent, N2 flow rate, flotation time, and volumes of the polyethylene glycol phase on the recovery were investigated in detail, and the optimal conditions were selected: 50 wt% polyethylene glycol 1000 ethanol solvent as the flotation solvent, pH 4, 350 g/L of (NH4 )2 SO4 concentration in aqueous phase, 40 mL/min of N2 flow rate, 30 min of flotation time, 10.0 mL of flotation solvent volume, and two times. After aqueous two-phase flotation concentration, the flotation products were purified by preparative high-performance liquid chromatography. The purities of the final products A and B were 98.1 and 99.0%. Product B was the mixture of three compounds based on the analysis of high-performance liquid chromatography at the temperature of 10°C, while product A was hyperoside after the identification by nuclear magnetic resonance. Astragalin, 3'-O-methylquercetin 3-O-ß-d-galactopyranoside, and 3'-O-methylquercetin 3-O-ß-d-glucopyranoside were obtained with the purity of 93.8, 97.1, and 99.2%, respectively, after the further separation of product B using preparative high-performance liquid chromatography.