Preparation, characterization and drug release properties of pH sensitive Zingiber officinale polysaccharide hydrogel beads.

The aim of this study was to prepare a drug carrier that could deliver oral insulin to the intestine. A hydrogel beads composed of sodium carboxymethyl cellulose (CMC), Zingiber offtcinale polysaccharide (ZOP) and chitosan (CS) were prepared by ionic gel method as insulin carrier. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and thermogravimetric (TGA) showed that the hydrogel was formed by metal ion coordination between ZOP and CMC and Fe3+, and CS was coated on the surface of the hydrogel ball in the form of non covalent bond. The results showed that the swelling process of hydrogel spheres has significant pH sensitivity. In addition, the hydrogel beads successfully coated insulin, and the drug loading rate (DL) of (ZOP/CMC-Fe3+)@CS could reach 69.43 ± 7.32 mg/g, and the entrapment efficiency (EE) could reach 66.94 ± 7.43 %. In vitro release experiments, the release rate of (CMC/ZOP-Fe3+)@CS in simulated gastric fluid (SGF) for 2 h was <20 %, and the cumulative release rate of insulin after 9 h in simulated intestinal fluid (SIF) reached over 90 %. The results showed that the hydrogel beads prepared in this work could be used as a potential carrier for delivering oral insulin.

Drought priming at seedling stage improves photosynthetic performance and yield of potato exposed to a short-term drought stress.

Potato (Solanum tuberosum L.) is an important food and vegetable crop worldwide. In recent years, the arid environment resulting from climate change has caused a sharp decline in potato yield. To clarify the effect of drought priming at the seedling stage on the tolerance of potato plants to drought stress during tuber expansion, we conducted a pot experiment to investigate the physiological response of the plants generated from seed potatoes of the variety 'Favorita' to varied water supply conditions: normal water supply at the seedling stage (control), normal water supply at the seedling stage and drought stress at the mid-tuber-expansion stage (non-primed), and drought priming at the seedling stage plus drought stress at the mid-tuber-expansion stage (primed). Drought priming resulted in an increase in the number of small vascular bundles in potato plants compared to non-primed plants. It also altered the shape and density of stomata, enhancing water use efficiency and reducing whole-plant transpiration. The primed plants maintained the basal stem cambium for a longer time under drought stress, which gained an extended differentiation ability to generate a greater number of small vascular bundles compared to non-primed plants. Drought priming increased the amount and rate of dry matter translocation, and so reduced the adverse effects on tubers of potato under drought stress. Therefore, drought priming at the seedling stage improved the photosynthetic performance and yield, and probably enhanced the drought tolerance of potato.

Structural characterization and biological activities of polysaccharide iron complex synthesized by plant polysaccharides: A review.

Iron deficiency anemia can lead to a variety of functional disorders, which is one of the highest incidence of nutrient deficiency diseases. The direct addition of iron to food will not only brings difficulties to the production of products, but also brings damages to human body. In recent years, international studies have shown that polysaccharide iron complex (PIC) not only has a variety of pharmacological activities of polysaccharide itself, but also has the function of supplementing iron, so it is a good iron supplement. With the advantages of good solubility, high iron content, low gastrointestinal irritation and high bioavailability, PIC is an effective iron supplement for iron deficiency anemia and has attracted more and more attention. In this paper, the different preparation methods, structural characterization, biological activities and clinical applications of PIC synthesized by natural polysaccharides from plant were reviewed, in order to provide theoretical basis for the development and application of PIC.

[Correlation analysis between quality characteristics and commercial specifications of Panacis Quinquefolii Radix].

This study was aimed to analyze the correlation between commercial specifications of Panacis Quinquefolii Radix and quantitative indexes of sevent kinds of ginsenosides (ginsenosides Rg¹, Re, Rb¹, Rc, Rb2, Rb3, Rd) contained in Panacis Quinquefolii Radix by using high performance liquid chromatography (HPLC), explore the correlation between the characteristics of the traditional Panacis Quinquefolii Radix specifications and modern chemical quantitative indicators, and provide a theoretical basis for the quality grade evaluation of Panacis Quinquefolii Radix. The HPLC fingerprint method was used to analyze 40 batches of Panacis Quinquefolii Radix. A total of 19 peaks were marked, and the similarity was above 0.900 for all samples. On this basis, processing methods, product specifications, contents of 7 components, and the total contents of ginsenoside Rg¹, Re and Rb¹ were used as the original variables for cluster analysis and principal component analysis. The results showed great correlation between the quality of Panacis Quinquefolii Radix and the information on their origins, but the difference was less with the characteristics of traditional commercial specifications, indicating some limitations in the division of commercial specifications of Panacis Quinquefolii Radix. The results revealed the intrinsic relationship between the product specifications, traditional qualitative indexes, and quantitative indexes of chemical components of Panacis Quinquefolii Radix, providing a new idea for the objective comprehensive evaluation of the quality of Panacis Quinquefolii Radix.

[Rubrofusarin glucosides of Berchemia polyphylla var. leioclada and their scavenging activities for DPPH radical].

OBJECTIVE: To study the rubrofusarin glucosides from whole plants of Berchemia polyphylla var. leioclada, and their scavenging activities for 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. METHOD: The chemical constituents were isolated and purified via repeated silica gel and Sephadex LH-20 column chromatography. Their structures were elucidated by spectral analysis and the compounds were tested for their scavenging activities on DPPH radical. RESULT: Three rubrofusarin glucosides compounds were isolated and identified as rubrofusarin-6-O-beta-D-glucopyranoside (1), rubrofusarin-6-O-beta-D-(6'-O-acetyl) glucopyranoside (2), rubrofusarin-6-O-alpha-L-rhamnosyl-(1-6) -O-beta-D-glucopyranside (3). Three isolated compounds showed strong scavenging activities on DPPH radical, the concentration of half elimination ratio( micromol x L(-1)) of VitC and Compounds 1-3 were 18.2, 40.5, 23.3 and 13.6, respectively. CONCLUSION: Compounds 1-3 were isolated from this plant for the first time and compound 2 was a new compound. They showed significant antioxidant activity, and the scavenging activity of compound 3 was a little stronger than that of VitC.

[Studies on separation, purification and structure characteristics of a polysaccharide LTC-II from Pyrola corbieri].

OBJECTIVE: To characterize the structure of polysaccharide LTC-II obtained from Pyrola corbieri. METHOD: The polysaccharide was extracted from P. corbieri by hot water and ethanol precipitation. Crude polysaccharide was purified by DEAE-Cellulose chromatography and Sephacryl S-300 HR column chromatography. The purity and molecular weight of polysaccharide was determined by gel permeation chromatography. UV, IR, optical rotation, complete acid hydrolysis, periodate oxydation, Smith degradation, partial acid hydrolysis and methylation analysis were applied to determine the structural features. RESULT: A homogeneous fraction LTC-II was obtained and its relative molecular mass was 22 000 Da. It consisted of arabinose, mannose, glucose, galactose in the molar ratio of 35. 2: 1.0: 13. 4: 4. 2. LTC-II had a backbone consisting glucose, mannose, galactose and mainly contained (1 --> 6)-linkaged glucose. The side chain possessed arabinose, glucose, galactose and mainly contained (1 --> 5)-linkaged arabinose. The terminal sugar were mainly glucose and galactose. CONCLUSION: Studies on the preliminary characterization of polysaccharide LTC-II from P. corbieri for the first time.