ABSTRACT
Objective: Phenylalanine ammonia-lyase gene (PAL) is one of the key enzymes associated with stress resistance in secondary metabolism pathway of plants. Exploring its sequence information and expression profiling information in stress response could comprehensively peep at the protein structure, functions and signal network of plant stress resistance. Methods: The full cDNA length of PAL from Bletilla striata was cloned by RT-PCR and RACE approaches. Physicochemical properties and conserved domain of BsPAL protein were determined by a series of bioinformatics tools as Protparam, SOPMA, SWISS-MODEL, etc. Multiple alignment and phylogenetic tree were achieved by DNAMAN and MEGA Software, respectively. The qPCR was employed to examine the expression profiles of BsPAL under exogenous hormone stress. Results: The full cDNA of BsPAL was 2 708 bp, encoding a 797 amino-acid protein with a molecular weight of 86 216.94 and an isoelectric point (pI) of 6.24. The BsPAL protein included the typical structural domain and active site of PALs in other plants, and without transmembrane region, which was more homologous with PALs of Dendrobium officinale and Phalaenopsis aphrodita. The qPCR Results: revealed the expression level of BsPAL in roots was much higher than that in leaves and stems. Under MeJA treatment, the expression trend of BsPAL was first gradually ascending and then descending, while SA treatment had the reverse effect. Conclusion: The BsPAL’s sequence characterizing, expression profiling and responding patterns against SA and MEJA provided a research basis for elucidating the metabolic pathways of phenylpropanoid and hormone signaling research in B. striata.
ABSTRACT
Objective: Bletilla striata polysaccharide (BSP-1) extracted from the stem tubers of B. striata was purified to study the structural properties and antitumor activity. Methods: The crude polysaccharide was fractionated by DEAE-cellulose column chromatography, and three fractions were obtained including BP-1, BP-2, and BP-3, respectively, BP-1 was further purified by SephadexG-200 column chromatography, and a sub-fraction named BSP-1 was obtained. Subsequently, HPGPC, IR spectroscopy, gas chromatography (GC), GC coupled to mass spectrometry (GC-MS) and methylation analysis, and 1H- and 13C-NMR were employed to characterize the structural properties of the polysaccharide fractions. Moreover, the anticancer activity was investigated in vivo. Results: The results showed that the molecular weight of BSP-1 were 4.72 × 105. BSP-1 was consisted of mannose (Man) and glucose (Glc) residues. The backbone of BSP-1 was composed of β-1,4-linked Man and Glc residues at the end with a molar ratio of 8:1. BSP-1 could inhibit the tumor proliferation of HepG2-bearing mice. The tumor weight of mice was significantly inhibited by BSP-1 with inhibitory rate of 66.42%. Conclusion: Structural characterization of BSP-1 provides the significant reference for the further development and elucidation of polysaccharides from B. striata as new drugs.
ABSTRACT
Objective: To study the glycoside chemical constituents of Bletilla striata grown in Guizhou Province. Methods: The glycoside chemical constituents were separated and purified by silica gel column chromatography, MCI, gel column chromatography, medium pressure preparation, highperformance liquid chromatography and other modern separation methods. The structures were identified based on the spectral data. Results: Thirteen glycosides were isolated from the 95% ethanol extracts: 1-methyl-3-phenylpropyl-β-D-glucopyranoside (1), 1-(4-β-D-glucopyranosyl oxybenzyl) 4-ethyl (2R)-2-isobutylmalate (2), 3’,5- dimethoxy-bibenzyl-3-O-β-D-glucopyranoside (3), syringaresinol mono-β-D-glucoside (4), 4-O-(6’-O-glucosyl-p-coumaroyl)-4- hydroxybenzyl alcohol (5), (4-hydroxyphenyl) methyl-β-D-glucopyranoside (6), 4-methylphenyl-β-D-glucopyranoside (7), benzyl-β-D- glucopyranoside (8), phenyl-β-D-glucopyranoside (9), 4-[(acetyloxy) methyl] phenyl-β-D-glucopyranoside (10), batatasin III-3-O- glucoside (11), gastrodin (12) and 4-(4-β-D-glucopyranosyl-oxybenzyl)-(2R)-2-isobutylmalate (13). Conclusion: Compound 1 is a new natural product. Compounds 3-6 are isolated from this plant for the first time; Compounds 2, 7-13 are obtained from this genus for the first time.
ABSTRACT
Rhizoma Bletillae is in high demand as a traditional Chinese medicine, and the natural resources have been severely damaged due to excessive exploitation. Because Bletilla striata seeds are small and have no endosperm, the seed germination rate is low in natural conditions. Traditional division propagation could not meet the demands of large-scale cultivation. Tissue culture can provide many seedlings in a short time and is more effective and convenient than other methods. Most studies on tissue culture of B. striata selected seeds as explants. This review summarized the processes of the aseptic seed germination pathway. It included such stages as seed germination, proliferation of clusters of buds, induction of rooting and transplanting of seedlings. Influential factors as well as optimum combination and concentration of the plant growth regulators of each stage were also summarized. The further research on tissue culture of B. striata was also prospected.
ABSTRACT
N. By contraries,the effect of N,P_2O_5,and K_2O fertilizer on output of B.striata could be in the order of K_2O
ABSTRACT
Objective To investigate the relative molecular weight of polysaccharides in Bletilla striata by matrix-assisted laser desorption ionizatior/time-of-flight mass (MALDI-TOF-MS). Methods 2, 5-Dihydroxybenzoic acid (DHB) as a matrix was used. By drop drying at room temperature the proportion of the matrix and polysaccharide sample was 1.5∶1. Baseline mode and laser intensity at 1 500-2 500 units were carried out. Results The relative molecular weights of polysaccharides in B. striata were 6?104-3?105, whose distribution rang was wide. Conclusion The relative molecular weights of polysaccharides in B. striata are obtained by MALDI-TOF-MS technique in the proportion of DHB-polysaccharides in B. striata 1.5∶1, which is valuable for the preparation and good quality by the direct drop drying method.
ABSTRACT
Objective To compare the pharmacodynamics of common Bletilla striata powder(80 and 200 meshes) with ultra-fine powder of B.striata on experimental gastric ulcer in rats and to clarify how much the dose of B.striata was decreased after superfine comminution.Methods The models of gastric ulcer were set up by anhydrous alcohol and acetic acid to measure the gastric ulcer area and count out the inhibitory rate;The tissue slice of gastric ulcer cicatrix was got far HE staining.Based on the viewpoint of pathology the morbid state was observed.Results B.striata powder could decrease the gastric ulcer area significantly,and the groups of ultra-fine powder were advantaged to the others.Conclusion After superfine comminution,the potency of B.striata can be improved with its dose reducing.It is good for mo-dernization of making dosage forms.
ABSTRACT
Objective To optimize the sulfation-conditions of Bletilla striata polysaccharide (BSPS). Methods BSPS was sulfated with chlorsulfonic acid-pyridine. Reagent proportion, reaction temperature, and reaction time were selected with substitution degree and yield as index by L_9(3~4) orthogonal design. Results Results showed that the condition with 6∶1 volume ratio of pyridine and chlorine sulfonic acid, reaction temperature of 85 ℃, reaction time of 2 h was the optimum. Conclusion The optimal method for sulfation of BSPS is feasible, and it provides valuable parameters for further enlarged test.