Deep eutectic solvent-homogenate based microwave-assisted hydrodistillation of essential oil from Litsea cubeba (Lour.) Pers. fruits and its chemical composition and biological activity.

As an important natural product, the sufficient separation of plant essential oil (EO) is helpful to improve its utilization value. In this work, deep eutectic solvent-homogenate based microwave-assisted hydrodistillation (DES-HMAHD) was developed and applied to isolate EO from the fruits of Litsea cubeba (Lour.) Pers. Different types of DES were investigated in terms of the EO kinetics and composition, among which oxalic acid/choline chloride (OA/ChCl) had obvious advantages. Following, molar ratio of OA and ChCl (1:1), water content (50%), liquid-solid ratio (12.5:1 mL/g), homogenate time (2 min), and microwave power (700 W) were found to be the optimum conditions. Gas chromatography-mass spectrometer (GC-MS) analysis showed that the EO isolated from DES-HMAHD contained a large proportion of m-cymene and trans-linalool oxide, which were quite different from the conventionally reported L. cubeba EO. In addition, the proposed DES-HMAHD resulted in higher separation efficiency and economic value, as well as lower environmental impact, as compared with other techniques. Afterwards, the EO isolated by different methods was evaluated from the perspective of biological activity. The EO obtained by DES-HMAHD showed higher antioxidant activity (DPPH and ABTS) but lower antifungal activity, which was related to its chemical composition. In general, DES-HMAHD produced a kind of L. cubeba EO with different components, which provided a scientific foundation for the sufficient isolation of plant EO and its application in the natural products.

Synthesis and application of novel silver magnetic amino silicone adhesive particles for preparation of high purity α-linolenic acid from tree peony seed oil under applied magnetic field.

Silver magnetic amino silicone adhesive (Fe3O4@SiO2@NH2@Ag) particles were prepared for the purification of α-linolenic acid from tree peony seed oil under applied magnetic field. First, Fe3O4@SiO2@NH2@Ag particles were prepared and physicochemically characterized, including XRD, TG, FTIR, SEM, magnetic hysteresis curves and elemental analysis. The static process for the purification of α-linolenic acid using Fe3O4@SiO2@NH2@Ag particles was investigated, including adsorption curve, desorption curve, elution solvent composition and adsorption isotherm. The result indicated that 0-1-4% acetone-n-hexane elution solvent was selected for the gradient elution process, 2 h and 60 min were the time required to reach adsorption and desorption equilibrium, 20 °C was selected as the adsorption temperature, Langmuir model was suitable to fit and explain the equilibrium data, and the adsorption process was spontaneous and exothermic. Under applied magnetic field, the dynamic process for the purification of α-linolenic acid using Fe3O4@SiO2@NH2@Ag particles was investigated, and the optimum conditions were 20:1 µL/g loading amount, 0.5 mL/min flow rate and 51.73 Oe magnetic field intensity. After purification, the purity and recovery ratio of α-linolenic acid were calculated to be 94% and 74%, respectively. Furthermore, the recycled Fe3O4@SiO2@NH2@Ag particles still achieved better purification result. Therefore, the developed method shows a good application prospect in the field of separation and purification of α-linolenic acid.

Magnetically stabilized bed packed with synthesized magnetic silicone loaded with ionic liquid particles for efficient enrichment of flavonoids from tree peony petals.

In this work, synthesized magnetic silicone loaded with ionic liquid (Fe3O4@SiO2@IL) particles combined with gas-liquid-solid magnetically stabilized bed (GLS-MSB) were applied to enrich flavonoids from tree peony petal extraction solution. The magnetic core (Fe3O4) encased in silica was conducive to its rapid and efficient separation, and the modification of silica with ionic liquids (ILs) could provide the functional groups for selective adsorption of flavonoids. Furthermore, the magnetic materials were evenly dispersed in the GLS-MSB system, realizing the adequate contact and causing the positive influence on the result. After physicochemical characterization, the prepared Fe3O4@SiO2@IL (IL=VBimBr) particles were validated in the enrichment performance of flavonoids, including the type of ionic liquid loaded, desorption solution, adsorption and desorption kinetics. The adsorption kinetics obeyed the pseudo-second-order model, the adsorption isotherms were consistent with the Langmuir equation, and the adsorption process was spontaneous and exothermic. Additionally, the dynamic processes using GLS-MSB packed with Fe3O4@SiO2@IL particles were evaluated systematically, deriving the optimum conditions (5 mL/min liquid flow rate, 130 mL Loading amount and 42.55 Oe magnetic field intensity) and improving the purity of flavonoids. After enrichment, the Fe3O4@SiO2@IL particles were successfully recycled and reused. Overall, the developed method offers a great potential for the enrichment of flavonoids from natural materials.

Insulin resistance in vitamin D-deficient mice is alleviated by n-acetylcysteine.

Vitamin D deficiency will lead to insulin resistance. In the current study, vitamin D3 1α-Hydroxylase ["1α(OH)ase"] knockout mice were generated to mimic vitamin D deficiency in vivo. As compared to the wild-type mice, the liver tissues of the knockout mice showed impaired insulin signaling, decreased glucose transporter 4 expression and increased reactive oxygen species production. Meanwhile, p53-p21 activation, apoptosis intensity and pro-inflammatory cytokines (IL-6, IL-1 and MIP-1α) level were significantly increased in the knockout mice livers. Significantly, such effects in the knockout mice were largely attenuated by supplement with anti-oxidant n-acetylcysteine (NAC). Remarkably, insulin resistance and metabolic abnormalities in the knockout mice were largely alleviated after treatment of NAC. Therefore, inhibition of oxidative stress by NAC alleviated insulin resistance in vitamin D-deficient mice. Oxidative stress could be the primary cause of insulin resistance by vitamin D deficiency.

Optimization of ultrasonic circulating extraction of samara oil from Acer saccharum using combination of Plackett-Burman design and Box-Behnken design.

In this study, ultrasonic circulating extraction (UCE) technique was firstly and successfully applied for extraction of samara oil from Acer saccharum. The extraction kinetics were fitted and described, and the extraction mechanism was discussed. Through comparison, n-hexane was selected as the extraction solvent, the influence of solvent type on the responses was detailedly interpreted based on the influence of their properties on the occurrence and intensity of cavitation. Seven parameters potentially influencing the extraction yield of samara oil and content of nervonic acid, including ultrasound irradiation time, ultrasound irradiation power, ultrasound temperature, liquid-solid ratio, soaking time, particle size and stirring rate, were screened through Plackett-Burman design to determine the significant variables. Then, three parameters performed statistically significant, including liquid-solid ratio, ultrasound irradiation time and ultrasound irradiation power, were further optimized using Box-Behnken design to predict optimum extraction conditions. Satisfactory yield of samara oil (11.72±0.38%) and content of nervonic acid (5.28±0.18%) were achieved using the optimal conditions. 1% proportion of ethanol in extraction solvent, 120°C of drying temperature and 6.4% moisture were selected and applied for effective extraction. There were no distinct differences in the physicochemical properties of samara oil obtained by UCE and Soxhlet extraction, and the samara oil obtained by UCE exhibited better antioxidant activities. Therefore, UCE method has enormous potential for efficient extraction of edible oil with high quality from plant materials.

An approach for extraction of kernel oil from Pinus pumila using homogenate-circulating ultrasound in combination with an aqueous enzymatic process and evaluation of its antioxidant activity.

In this study, a novel approach involving homogenate-circulating ultrasound in combination with aqueous enzymatic extraction (H-CUAEE) was developed for extraction of kernel oil from Pinus pumila. Following comparison of enzyme types and concentrations, an enzyme mixture consisting of cellulase, pectinase and hemicellulase (1:1:1, w/w/w) at a concentration of 2.5% was selected and applied for effective oil extraction and release. Several variables potentially influencing extraction yields, namely, homogenization time, incubation temperature, incubation time, mark-space ratio of ultrasound irradiation, ultrasound irradiation power, liquid-solid ratio, pH and stirring rate, were optimized by Plackett-Burman design. Among the eight variables, incubation temperature, incubation time and liquid-solid ratio were statistically significant and were further optimized by Box-Behnken design to predict optimum extraction conditions and ascertain operability ranges for maximum extraction yield. Under optimum operating conditions, extraction yields of P. pumila kernel oil were 31.89±1.12% with a Δ5-unsaturated polymethylene interrupted fatty acid content of 20.07% and an unsaturated fatty acid content of 93.47%. Our study results indicate that the proposed H-CUAEE process has enormous potential for efficient and environmentally friendly extraction of edible oils.

Application of ionic liquids in vacuum microwave-assisted extraction followed by macroporous resin isolation of three flavonoids rutin, hyperoside and hesperidin from Sorbus tianschanica leaves.

Rutin, hyperoside and hesperidin were effectively extracted from Sorbus tianschanica leaves by an ionic liquid vacuum microwave-assisted method. A series of ionic liquids with various anions and alkyl chain length of the cations were studied and the extraction was performed in [C6mim][BF4] aqueous solution. After optimization by a factorial design and response surface methodology, total extraction yield of 2.37mg/g with an error of 0.12mg/g (0.71±0.04mg/g, 1.18±0.06mg/g and 0.48±0.02 for rutin, hyperoside and hesperidin, respectively) was achieved under -0.08MPa for vacuum, 19min and 420W for microwave irradiation time and power, and 15mL/g for liquid-solid ratio. The proposed method here is more efficient and needs a shorter extraction time for rutin, hyperoside and hesperidin from S. tianschanica leaves than reference extraction techniques. In stability studies performed with standard rutin, hyperoside and hesperidin, the target analytes were stable under the optimum conditions. The proposed method had a high reproducibility and precision. In addition, separation of rutin, hyperoside and hesperidin from [C6mim][BF4] extraction solution was completed effectively by AB-8 macroporous resin adsorption and desorption process. Ionic liquid vacuum microwave-assisted extraction is a simple, rapid and efficient sample extraction technique.

Ionic liquids-lithium salts pretreatment followed by ultrasound-assisted extraction of vitexin-4″-O-glucoside, vitexin-2″-O-rhamnoside and vitexin from Phyllostachys edulis leaves.

An efficient method for the extraction of vitexin, vitexin-4″-O-glucoside, and vitexin-2″-O-rhamnoside from Phyllostachys edulis leaves comprises heat treatment using an ionic liquid-lithium salt mixture (using 1-butyl-3-methylimidazolium bromide as the solvent and lithium chloride as the additive), followed by ultrasound-assisted extraction. To obtain higher extraction yields, the effects of the relevant experimental parameters (including heat treatment temperature and time, relative amounts of 1-butyl-3-methylimidazolium bromide and lithium chloride, power and time of the ultrasound irradiation, and the liquid-solid ratio) are evaluated and response surface methodology is used to optimize the significant factors. The morphologies of the treated and untreated P. edulis leaves are studied by scanning electron microscopy. The improved extraction method proposed provides high extraction yield, good repeatability and precision, and has wide potential applications in the analysis of plant samples.

Electroacupuncture attenuates hepatic lipid accumulation via AMP-activated protein kinase (AMPK) activation in obese rats.

BACKGROUND: Electroacupuncture (EA) may offer an effective alternative approach for the treatment of obesity. EA mobilizes energy stores, but its effect on hepatic lipid metabolism is unknown, and the underlying mechanisms remain unclear. OBJECTIVE: To examine the effect of EA on hepatic lipid accumulation in diet-induced obese (DIO) rats, and to explore potential underlying mechanisms. METHODS: Male Sprague-Dawley rats were fed a normal diet (control group, n=10) or a high-fat diet (HFD) for 12 weeks to induce obesity. Those exhibiting diet-induced obesity were subdivided into two groups, one receiving EA (DIO+EA group, n=10) and one left untreated (DIO group, n=10) and observed for a further 4 weeks. Body, liver and fat pad weight were measured, and liver injury was assessed histologically as well as by measuring serum values of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Hepatic triglyceride (TG) and total cholesterol were quantified by enzymatic colorimetric methods. Expression of liver AMP-activated protein kinase (AMPK), acetyl-coenzyme A carboxylase (ACC), and carnitine palmitoyltransferase (CPT-1) was measured by Western blotting. RESULTS: EA treatment led to a reduction in body, liver and fat pad weight in DIO rats. This was accompanied by decreases in hepatic TG and total cholesterol values, fatty droplet accumulation, and serum concentrations of ALT and AST. Furthermore, EA treatment restored phosphorylation levels of AMPK (Thr(172)) and ACC (Ser(79)) inhibited by HFD, and increased CPT-1 expression. CONCLUSIONS: EA reduces HFD-induced hepatic lipid accumulation, an effect that appears to be mediated through AMPK signalling pathways. Our results shed new light on the mechanisms by which EA may reduce obesity.

Ionic liquid-based vacuum microwave-assisted extraction followed by macroporous resin enrichment for the separation of the three glycosides salicin, hyperin and rutin from Populus bark.

An effective ionic liquid vacuum microwave-assisted method was developed for extraction of the thermo- and oxygen-sensitive glycosides salicin, hyperin and rutin from Populus bark due to the strong solvating effects of ionic liquids on plant cell walls. In this study, [C4mim]BF4 solution was selected as the extracting solution for extraction of the target analytes. After optimization by single factor experiments and response surface methodology, the optimum condition parameters were achieved, which included 1.0 M [C4mim]BF4, 2 h soaking time, -0.08 MPa vacuum, 20 min microwave irradiation time, 400 W microwave irradiation power and 25 mL/g liquid/solid ratio. Under the optimum conditions, higher extraction yields of salicin (35.53 mg/g), hyperin (1.32 mg/g) and rutin (2.40 mg/g) were obtained. Compared with other extraction methods, the developed method provided higher yields of the three target components after a relatively shorter extraction time (20 min). No obvious degradation of the target analytes was observed under the optimum conditions in performed stability studies and the proposed method had a high reproducibility. Meanwhile, after adsorption and desorption on macroporous D101 resin, the target analytes can be effectively separated from the [C4mim]BF4 ionic liquid extraction solution and the yields of salicin, hyperin and rutin were 89%, 82% and 84%, respectively. The recovered [C4mim]BF4 ionic liquid presented a good extraction effect on the three analytes after recycling five times.

Hyperbaric oxygen treatment and enteral nutrition support with glutamine relieves traumatic brain injury in the rats.

The abnormal metabolic processes following traumatic brain injury (TBI) have been proposed to contribute to secondary injuries after TBI. Therefore, enteral nutrition (EN) support for TBI patients has received more attention. This study aimed to evaluate the complimentary effects of enteral nutrition with glutamine and hyperbaric oxygen (HBO) on the recovery of TBI. TBI model was established in SD rats, which were randomly divided into four groups: TBI, TBI + HBO, TBI + GLN, and TBI + HBO + GLN. Neuronal apoptosis in penumbra area was detected by TUNEL. Serum prealbumin level was detected by ELISA. Motor function was evaluated by beam-balance test. We found that the body weight of the rats had no significant differences in different groups before and after injury. Among the four groups, beam-balance test score was the lowest, serum prealbumin level was the highest, and neuronal apoptosis rate was the lowest in TBI + HBO + GLN group on day 3 and 7 after TBI. In conclusion, our data suggest that hyperbaric oxygen combined with enteral nutrition support with glutamine is effective in reducing neuronal apoptosis, increasing serum prealbumin concentration and improving neurological function after TBI injury.