Extraction and purification of capsaicin from capsicum oleoresin using an aqueous two-phase system combined with chromatography.

Capsaicin was extracted from capsicum oleoresin using an aqueous two-phase system (ATPS) composed of an ethylene oxide-propylene oxide (EOPO) copolymer, salt and ethanol. Capsaicin was concentrated in the top polymer-rich phase. To determine the optimal conditions, the partitioning of capsaicin in the ATPS was investigated, considering a single-factor experiment including the salt concentration, polymer concentration, buffer pH, ethanol concentration, sample loading and extraction duration. Response surface methodology was applied to investigate the effects of the polymer concentration, buffer pH and sample loading on capsaicin partitioning. A capsaicin yield of 95.5% was obtained using the optimal extraction system, which consisted of 16.3% UCON 50-HB-5100/10% K2HPO4/1% ethanol, a buffer pH of 4.35 and 0.24g of capsicum oleoresin. Capsaicin was purified from the capsaicinoid extract using a two-step macroporous adsorption resin (MAR) method. After purification using non-polar MAR ADS-17, the recovery and purity of capsaicin were 83.7% and 50.3%, respectively. After purification using weakly polar MAR AB-8, the recovery and purity of capsaicin were 88.0% and 85.1%, respectively.

Aqueous two-phase extraction combined with chromatography: new strategies for preparative separation and purification of capsaicin from capsicum oleoresin.

Capsaicin was preparatively separated and purified from capsicum oleoresin with a new method combined with aqueous two-phase extraction (ATPE) and chromatography. Screening experiments of ATPE systems containing salts and hydrophilic alcohols showed that potassium carbonate/ethanol system was the most suitable system for capsaicin recovery among the systems considered. Response surface methodology was used to determine an optimized aqueous two-phase system for the extraction of capsaicin from capsaicin oleoresin. In a 20 % (w/w) ethanol/22.3 % (w/w) potassium carbonate system, 85.4 % of the capsaicin was recovered in the top ethanol-rich phase while most oil and capsanthin ester were removed in the interphase. The capsaicinoid extract was then subjected to two chromatographic steps using D101 macroporous resin and inexpensive SKP-10-4300 reverse-phase resin first applied for the purification of capsaicin. After simple optimization of loading/elution conditions for D101 macroporous resin chromatography and SKP-10-4300 reverse-phase resin chromatography, the purities of capsaicin were improved from 7 to 85 %. In the two chromatography processes, the recoveries of capsaicin were 93 and 80 % respectively; the productivities of capsaicin were 1.86 and 4.2 (g capsaicin/L resin) per day respectively. It is worth mentioning that a by-product of capsaicin production was also obtained with a high purity (90 %).

Combination of aqueous two-phase extraction and cation-exchange chromatography: new strategies for separation and purification of alliin from garlic powder.

In this study, a two-step process combining aqueous two-phase extraction (ATPE) with chromatography was developed for extraction and purification of alliin from garlic powder. The partition coefficient and yield value of alliin in different types of aqueous two-phase system (ATPS) were compared and response surface methodology (RSM) was used for analyzing and optimizing the extraction process. The optimal extraction conditions of 19% (w/w) (NH4)2SO4, 20% (w/w) 1-prpanol, at 30°C, pH 2.35 with 8.54% (w/w) NaCl was chosen based on the higher yield. Compared to the results obtained with the conventional extraction method, this method had an evident advantage on yield (20.4mg/g versus the original yield of 15.0mg/g) and the concentration of alliin in extract solution by ATPE was close to three times of that with conventional extraction. The purification of alliin was carried out with the ammonium form of sulfonic acid cation-exchange resins 001×7. Sample solution with alliin concentration of 1mg/mL was passed through resins and the desorption of alliin was accomplished by water at the flow velocity of 0.5mL/min, 1.5mL/min, respectively. The purity and recovery of alliin after purification were 80% and 76%, respectively.

First evidence for the anti-inflammatory activity of fucoxanthin in high-fat-diet-induced obesity in mice and the antioxidant functions in PC12 cells.

Obesity, characterized as a state of low-level inflammation, is a powerful determinant influencing the development of insulin resistance and progression to type 2 diabetes. The purpose of the present study was to investigate the anti-inflammatory activity of fucoxanthin in experimental high-fat-diet-induced obesity in mice and antioxidant activity in PC12 cells under oxidative stress situation. The anti-inflammatory potential of fucoxanthin in the regulation of maleic dialdehyde (MDA), polymorphonuclear cells (PMNs), interleukin-1ß (IL-1ß), inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), and cyclooxygenase-2 (COX-2) was determined by ELISA. Fucoxanthin significantly inhibited obesity-induced upregulation of the production of IL-1ß, TNF-α, iNOS, and COX-2. Moreover, fucoxanthin suppressed MDA and infiltration of PMNs. The protective effects were associated with lack of hypertrophy and crown-like structures in mammary gland. At the same time, fucoxanthin showed an advantage of antioxidant activity in PC12 cells under oxidative stress situation. These results suggest that supplementation of fucoxanthin is a promising strategy for blocking macrophage-mediated inflammation and inflammation-induced obesity and its associated complications.

Recombination and heterologous expression of allophycocyanin gene in the chloroplast of Chlamydomonas reinhardtii.

Heterogeneous expression of multiple genes in the nucleus of transgenic plants requires the introduction of an individual gene and the subsequent backcross to reconstitute multi-subunit proteins or metabolic pathways. In order to accomplish the expression of multiple genes in a single transformation event, we inserted both large and small subunits of allophycocyanin gene (apcA and apcB) into Chlamydomonas reinhardtii chloroplast expression vector, resulting in papc-S. The constructed vector was then introduced into the chloroplast of C. reinhardtii by micro-particle bombardment. Polymerase chain reaction and Southern blot analysis revealed that the two genes had integrated into the chloroplast genome. Western blot and enzyme-linked immunosorbent assay showed that the two genes from the prokaryotic cyanobacteria could be correctly expressed in the chloroplasts of C. reinhardtii. The expressed foreign protein in transformants accounted for about 2%-3% of total soluble proteins. These findings pave the way to the reconstitution of multi-subunit proteins or metabolic pathways in transgenic C. reinhardtii chloroplasts in a single transformation event.