Ultrasonic-assisted extraction, structure and antitumor activity of polysaccharide from Polygonum multiflorum.

Polygonum multiflorum is a popular Chinese herbal medicine with various pharmacological functions. In this study, the ultrasonic-assisted extraction condition, structural characterization and antitumor activity of a polysaccharide from roots of P. multiflorum were investigated. The ultrasonic-assisted extraction condition was optimized by single-factor experiments and response surface methodology. Results showed that the maximum extraction yield (5.49%) was obtained at ultrasonic power 158W, extraction temperature 62°C, extraction time 80min and ratio of water to material 20mL/g. The obtained crude polysaccharides were further purified to afford a neutral and an acidic fraction. The structure of the main neutral polysaccharide (named PPS with molecular weight of 3.26×10(5)Da) was characterized as a linear (1→6)-α-d-glucan by gas chromatography, Fourier transform-infrared spectroscopy, methylation analysis, 1D and 2D nuclear magnetic resonance. At the concentration of 400μg/mL, the inhibitory ratios of PPS on HepG-2 and BGC-823 cells were 53.35% and 38.58%, respectively. Results suggested this polysaccharide could be a potential natural antitumor agent.

Zhu W ，Xue X ，Zhang Z 《-》

Structural, physicochemical, antioxidant and antitumor property of an acidic polysaccharide from Polygonum multiflorum.

In this study, the structural characterization, physicochemical property, antioxidant and antitumor activity of an acidic polysaccharide (APS) from Polygonum multiflorum were investigated. Monosaccharide composition analysis showed APS was composed of arabinose, rhamnose, galactose and galacturonic acid in the molar ratio of 1.23:1.32:1.48:1.00. The presence of uronic acid was also confirmed by the bands at 1740, 1645 and 1425cm-1 on Fourier transform-infrared spectroscopy. Methylation and nuclear magnetic resonance analyses showed APS was mainly composed by the residues of →5)-α-l-Araf-(1→, →3)-β-d-Galp-(1→, →3,6)-β-d-Galp-(1→, →4)-α-d-GalAp-(1→ and →2)-α-l-Rhap-(1→ in the backbone. The non-reducing terminal α-l-Araf-(1→ was probably attached to the O-6 position of →3,6)-β-d-Galp-(1→ residues. Besides, APS exhibited rod-like and flaky shapes with rough surface. The initial decomposition of APS occurred at 172°C, and the rapidest weight loss rate of APS appeared at 320°C. Antioxidant activity assay showed the DPPH radical scavenging activity of APS was 67.5% at 1mg/mL. At the concentration of 400μg/mL, the antiproliferation activities of APS against HepG-2 and BGC-823 cells were 65.28% and 51.57%, respectively. Our results suggested APS could be a potential antioxidant and antitumor agent.

Zhu W ，Xue X ，Zhang Z 《-》

Polysaccharides from pineapple pomace: new insight into ultrasonic-cellulase synergistic extraction and hypoglycemic activities.

This study determined the optimal extraction conditions for ultrasonic-cellulase synergistic extraction of polysaccharides from pineapple pomace (PPP) using Plackett-Burman design and response surface methodology. The optimal hydrolysis temperature, ratio of material to water, pH value, hydrolysis time, ultrasonic power and the additive quantity of cellulase were 50 °C, 1:45 g/mL, 6.0, 100 min, 160 W and 2.0%, respectively, giving a extraction yield of 1.10 ± 0.03%. PPP was further isolated and purified by DEAE-52 cellulose and Sephadex G-100 chromatography columns, revealing four main elution peaks, named PPF0, PPF1, PPP2 and PPF3, were obtained. The molecular weight, monosaccharide compositions, structural features and appearance morphology of polysaccharide fractions (PPFs) were analyzed by high-performance liquid chromatography (HPLC), gel permeation chromatography (GPC), UV spectroscopy, fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). Furthermore, the hypoglycemic activities of PPFs with different concentrations were also investigated by insulin resistance HepG2 cells model in vitro. Results showed that PPF0, PPF1, PPF2 and PPF3 were composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose and fucose with molecular weight of 6.71 × 104, 1.11 × 104, 2.22 × 104 and 5.1 × 103 Da, respectively. All of them could alleviate the development of insulin resistance HepG2 cells with a dose-dependent relationship. The glucose consumption increased 46.4%, 50.5%, 82.1% and 53.6%; 86.8%, 81.6%, 86.8% and 84.2% at the concentration of 20 μg/mL, respectively, without or with insulin. These results suggested that PPFs can be explored as a potential hypoglycemic agent in biomedical and functional food.

Hu H ，Zhao Q ，Xie J ，Sun D ... -  《-》

Effects of extraction methods on the yield, chemical structure and anti-tumor activity of polysaccharides from Cordyceps gunnii mycelia.

This study was to investigate the effects of different extraction methods on the yield, chemical structure and antitumor activity of polysaccharides from Cordyceps gunnii (C. gunnii) mycelia. Five extraction methods were used to extract crude polysaccharides (CPS), which include room-temperature water extraction (RWE), hot-water extraction (HWE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and cellulase-assisted extraction (CAE). Then Sephadex G-100 was used for purification of CPS. As a result, the antitumor activities of CPS and PPS on S180 cells were evaluated. Five CPS and purified polysaccharides (PPS) were obtained. The yield of CPS by microwave-assisted extraction (CPSMAE) was the highest and its anti-tumor activity was the best and its macromolecular polysaccharide (3000-1000kDa) ratio was the largest. The PPS had the same monosaccharide composition, but their obvious difference was in the antitumor activity and the physicochemical characteristics, such as intrinsic viscosity, specific rotation, scanning electron microscopy and circular dichroism spectra.

Zhu ZY ，Dong F ，Liu X ，Lv Q ，YingYang ，Liu F ，Chen L ，Wang T ，Wang Z ，Zhang Y ... -  《-》

Ultrasonic extraction, antioxidant and anticancer activities of novel polysaccharides from Chuanxiong rhizome.

Ultrasonic-assisted extraction technology was employed to prepare Ligusticum chuanxiong Hort polysaccharide. Single factor test and orthogonal experimental design were used to optimize the extraction conditions. The results showed that the optimal extraction conditions consisted of ultrasonic temperature of 80°C, ultrasonic time of 40 min and water to raw material ratio of 30 mL/g. Three novel polysaccharides fractions, LCX0, LCX1 and LCX2, were isolated and purified from the crude polysaccharides using DEAE-52 cellulose and Sephadex G-100 column chromatography. The molecular weight and monosaccharide composition of three LCX polysaccharides fractions were analyzed with gel permeation chromatography (GPC) and HPLC analysis, respectively. Furthermore, the antioxidant and in vitro anticancer activities of the polysaccharides were investigated. Compared with LCX0, LCX2 and LCX1 showed relative higher antioxidant activity and inhibitory activity to the growth of HepG2, SMMC7721, A549 and HCT-116 cells. It is suggested that the novel polysaccharides from rhizome of L. chuanxiong could be promising bioactive macromolecules for biomedical use.

Hu J ，Jia X ，Fang X ，Li P ，He C ，Chen M ... -  《-》