Advanced Materials Research Vols. 1033-1034

Abstract: Ligusticum chuanxiong Hort. (Umbelliferae) has been prescribed widely to treat cardiovascular diseases in China for centuries. Senkyunolide I is a major bioactive component in L. chuanxiong that shows pharmacological activity against migraines and oxidative damage. Here, we identified the degradation products of senkyunolide I under different conditions (temperature, light alkaline) by ultra-high-performance liquid chromatography–quadrupole time-of-flight–tandem mass spectrometry (UPLC-QTOF-MS) analyses. Senkyunolide I was separated on an ACQUITY UPLC HSS T3 C18 (100 mm × 2.1 mm i.d., 1.8 μm) column using a binary eluent under gradient conditions. Analytes were detected by ESI/QTOF–MS/MS in positive ion mode to obtain MS and MS/MS spectra together with extracted molecular weights. Upon comparison with reference data, we concluded that senkyunolide I undergoes a ring-opening reaction under alkaline conditions (pH >10.0), and dual-key addition or hydration on 3,4-unsaturated bonds and branched terminal hydroxyl groups under high-temperature and aerobic conditions. With auxiliary application ¹H-NMR, we determined that partial isomerization of senkyunolide I takes place under bright light. In the method detailed here, the advantages of separation and identification of a complex system of small and medium-sized molecules was exploited using UPLC–QTOF–MS, not only to avoid complicated separation and purification, but also to isolate and identify trace amounts of degradation products that were previously difficult to identify.

Abstract: In this study, poly-β-hydroxybutyrate (PHB) was synthesized by moderately halophilic bacteria Halomonas venusta and identified by ¹H-NMR. The effects of different carbon sources, salt concentration, initial carbon nitrogen quality ratio, initial phosphate concentration were studied on the synthesis of PHB. The optimum conditions of the PHB synthesis were detemined. Glucose was as carbon source with the concentration of 80 g/L and salt concentration, initial carbon nitrogen ratio, initial phosphate concentration was 3%, 15 and 1.9 g/L respectively. Under the above conditions, a two-phase synthesis system of PHB was constructed. The PHB synthesis amount and yield of cell dry weight was reached up to 1.5 g/L and 69.19 wt.%, respectively. The efficient synthesis of PHB was realized.

Abstract: A novel and rapid synthesis of isoquercitrin using enzymatic hydrolysis of rutin under microwave irradiation was investigated. In the [Bmim][BF₄]-buffer (pH 9.0) system under microwave irradiation, rutin conversion, isoquercitrin yield and quercetin yield were 89.18%, 84.74% and 2.79%, respectively, in conditions of 5 min and 30 °C. The preparation cost of isoquercitrin was significantly reduced by decreasing reaction time (from 10 h to 5 min) and increasing reaction efficiency (by 120 times).

Abstract: Compond Danshen micropowder tablets and extraction tablets were firstly prepared respectively. Then the contents of salvianolic acid B, tanshinone IIA, tanshinone I, cryptotanshinone, notoginsenoside R1,ginsenoside Rg1 and ginsenoside Rb1 in these two kinds of tablets were determined by HPLC, and the results showed that the contents in micropowder tablets were more than them in extraction tablets. A pharmacokinetic comparative study of micropowder tablets with extraction tablets by intragastric administration was developed. Pharmacokinetic parameters suggested that micropowder tablets in rats in vivo bioavailability degree (AUC), peak concentration (Cmax) were 2.14, 1.64 times than the extraction tablets, respectively, and the Tmax of micropowder tablets was longer.

Abstract: A series of hepatic hydroxyl functional cholesterylated hepatic targeting liposome ligands T₁-T₆ were synthesized. Cholesterol as starting material, after esterification with p-toluenesulfonyl chloride to get cholesterol tosylate, then etherification with oligo ethylene ethanol (n=1-3) to get hydroxyl functional cholesterylated compounds T₁-T₃, T₁-T₃ were elongated by reaction with protected diethylene glycol and deprotected in acid condition to get T₄-T₆ . The target compounds affords cholesterylated hepatic targeting liposome ligands.

Abstract: A series of hepatic amino functional cholesterylated hepatic targeting liposome ligands L₁-L₆ were synthesized. Cholesterol as starting material, after esterification with p-toluenesulfonyl chloride to get cholesterol tosylate, then etherification with oligo ethylene ethanol (n=1-3) to get amino functional cholesterylated compounds T₁-T₃, T₁-T₃ were elongated by reaction with protected diethylene glycol and deprotected in acid condition to get T₄-T₆ . L₁-L₆ were mesylated and replaced by azido group, then hydrogenanted by hydrogen to get L₁-L₆.The target compounds affords cholesterylated hepatic targeting liposome ligands.

Abstract: Catalpol, an iridoid glycoside, has been verified to be of neuroprotection and may be a potential agent for the treatment of neurodegenerative disease. The extraction technology of catalpol has been tested in this paper. We used different extraction methods including extraction at room temperature (ERT), heat reflux extraction, Soxhlet extraction, ultrasonic extraction and microwave-assisted extraction (MAE) to evaluat the percentage extraction of catapol from Rehmannia glutinosa Libosch. The extracts were analyzed by high performance liquid chromatography (HPLC). Methanol (100%, v/v) extracted high percentage extraction of catapol compared to ethanol (60%, v/v) which achieved the highest percentage extraction of catapol in different concentration of ethanol. The results showed that the percentage extraction of catalpol from Rehmannia glutinosa Libosch by MAE was more efficient in short time followed by ultrasonic extraction, Soxhlet extraction, heat reflux extraction and ERT methods. MAE has need of 4 min, whereas ultrasonic extraction, Soxhlet extraction, heat reflux extraction and ERT techniques require 70, 140, 180 min and 60 h respectively, to leach higher percentage extraction of catalpol. The time taken by MAE was nearly 18 times less than the ultrasonic extraction, 35 times less than Soxhlet extraction, 45 times less than heat reflux extraction and 900 times less than ERT for the highest percentage extraction of catalpol. The present results showed that the high extraction efficiency and considerable saving of time by MAE were more competent than the conventional extraction techniques.

Abstract: A gas chromatography-mass spectrometry (GC-MS) method was developed for analyses of volatile and semivolatile components in Marsdeniae tenocissimae. The volatile and semivolatile components in stem of Marsdenia tenocissima are extracted by soxhlet extraction method with chloroform. The results show that 46 compositions were identified and accounted for 90.144% of the total peak areas. The major volatile and semivolatile components of stem were: alkanes (12.168%), alcohol (6.732%), aldehydes and ketones (7.272%), fatty acids (46.152%), Esters (13.068%), other (4.752%), respectively. The study provides useful data for further analysis of components of Marsdenia tenocissima.

Abstract: New red phosphorescent material, (E)-2-(4-fluorostyryl) benzo [d] thiazole (4-FSBT) iridium (III) dibenzoylmethane (DBM) complex [(4-FSBT)₂Ir (DBM)] is synthesized from 2-methyl benzothiazole, 4-fluorobenzaldehyde, iridium trichloride anhydrate and DBM. The complex is characterized by MS and ¹H-NMR. (4-FSBT)₂Ir (DBM) gives a photoluminescence at 625.8nm, phosphorescent quantum yield: Φ_{(4-FSBT)2Ir (DBM)} = 0.2 and E_HOMO = -4.7 eV, E_LUMO = -2.5eV, respectively. The complex may be a promising electrophosphorescent material.

Abstract: Series of starch succinates with different DS (degree of substitution) were synthesized by the reaction of succinic anhydride (SA) and starch in aqueous alkali slurry. Effects of reaction time and temperature, the mole ratio of Na₂CO₃ to SA and the amount of SA on DS and RE (reaction efficiency) were discussed. The maximum DS could be up to 0.241 and prolonging reaction time had no evident influence on DS. Apparent viscosity of starch solution was improved while resistance to shear-thinning was reduced after modification. FT-IR confirmed the reaction between SA and starch. The apparent surface change was observed by SEM. XRD showed no crystalline pattern change but crystallinity was reduced when DS was higher than 0.110.