A comparative study of supercritical fluid extraction and accelerated solvent extraction of lipophilic compounds from lignocellulosic biomass

The Box-Behnken experimental design technique investigated a comparative study of supercritical fluid extraction (SFE) and accelerated solvent extraction (ASE) of lipophilic compounds from pinewood sawdust. A response surface methodology was used to examine the effect of independent parameters and optimize the extraction yield of lipophilic compounds. The results showed that the increase in extraction temperature used for ASE positively influenced the yield of lipophilic compounds, whereas an increase in the flow rate of the cosolvent at temperature 50 °C, and pressure of 300 bar increased the yield achieved by SFE. The experimental data's quadratic polynomial models gave a coefficient of determination (R²) of 0.87 and 0.80 for ASE and SFE, respectively. The optimum conditions of ASE were temperature (160 °C), static time (12.5 mins), and static cycle (1), which resulted in a maximum yield of 4.2%. The optimum SFE conditions were temperature (50 °C), pressure (300 bar), carbon dioxide (CO₂) flow rate (3.2 ml/min), and a 2 ml/min cosolvent flow rate that yielded 2.5% lipophilic compounds. ASE yielded higher extraction efficiency than SFE. Fourier transform infra-red (FTIR) spectroscopy and thermal analyses TGA/DSC evaluated the ultimate analyses of the lipophilic extracts. The FTIR results confirmed the presence of aliphatic groups, hydroxyl groups, and carboxyl groups. The thermal analysis showed that the degradation temperature of the lipophilic compounds occurred between 250 and 450 °C. Thereafter, Pyrolysis-Gas Chromatography Mass Spectrometry (Py-GC/MS) was used to identify the lipophilic compounds, which showed that the extracts were rich in fatty acids and terpenes.     

超临界CO_2萃取木香顺气丸中木香和砂仁的工艺研究

目的优选木香顺气丸中木香和砂仁的超临界CO2萃取工艺。方法采用单因素及正交试验的方法,考察萃取压力、温度、时间、药材粒度对萃取率的影响。结果优选的萃取工艺为:木香、砂仁粉碎成粗粉,萃取压力30 MPa,温度40℃,萃取3 h。结论使用超临界CO2萃取工艺,操作简单,工艺稳定,萃取物得率高。     

A comparison between solid phase extraction and supercritical fluid extraction for the determination of fluconazole from animal feed

The application of supercritical fluid extraction with carbon dioxide and modified carbon dioxide for the determination of fluconazole from an animal feed was studied. A fractional factorial design approach was used to examine the significant experimental variables for quantitative extraction of fluconazole. Gas chromatography with either flame ionisation or mass selective detection was used for quantitation of the extracts. The results indicated that modifier (methanol) had the greatest effect on the recovery of fluconazole from the animal feed.     

白花丹参脂溶性成分超临界二氧化碳流体萃取与气相色谱-质谱分析

目的采用超临界二氧化碳流体萃取与气相色谱 质技术谱分析白花丹参脂溶性成分。方法采用正交实验,以萃取温度、萃取时间、萃取压强及夹带剂浓度为考察因素,以萃取率为指标,确定白花丹参脂溶性成分超临界二氧化碳萃取的最佳条件,并用气质联用技术对脂溶性化学成分进行分析。结果白花丹参脂溶性成分最佳提取工艺为萃取温度45 ℃,萃取时间1.5 h,萃取压强25 MPa,乙醇浓度90%。用气质联用技术从中鉴定了22种化合物,其中丹参酮类成分以铁锈醇（5.54%）、丹参酮ⅡA（12.54%）、隐丹参酮（8.39%）及异隐丹参酮（11.92%）为主。结论白花丹参脂溶性提取物可作为一种富含丹参酮类化合物和不饱和脂肪酸的重要原材料,该实验结果为白花丹参的进一步开发利用提供理论依据。     

Sedative and hypnotic effects of supercritical carbon dioxide fluid extraction from Schisandra chinensis in mice

Schisandra chinensis is a traditional Chinese medicine that has been used for treating insomnia and neurasthenia for centuries. Lignans, which are considered to be the bioactive components, are apt to be extracted by supercritical carbon dioxide. This study was conducted to investigate the sedative and hypnotic activities of the supercritical carbon dioxide fluid extraction of S. chinensis (SFES) in mice and the possible mechanisms. SFES exhibited an obvious sedative effect on shortening the locomotor activity in mice in a dose-dependent (10–200 mg/kg) manner. SFES (50 mg/kg, 100 mg/kg, and 200 mg/kg, intragstrically) showed a strong hypnotic effect in synergy with pentobarbital in mouse sleep, and reversal of insomnia induced by caffeine, p-chlorophenylalanine and flumazenil by decreasing sleep latency, sleep recovery, and increasing sleeping time. In addition, it produced a synergistic effect with 5-hydroxytryptophan (2.5 mg/kg, intraperitoneally). The behavioral pharmacological results suggest that SFES has significant sedative and hypnotic activities, and the mechanisms might be relevant to the serotonergic and γ-aminobutyric acid (GABA)ergic system.     

Chemical composition and antioxidant activity of volatiles from Patrinia Villosa Juss obtained by optimized supercritical fluid extraction

Supercritical CO(2) fluid extraction (SFE-CO(2)) was used to extract volatiles from Patrinia Villosa Juss. An orthogonal test L(9) (3)(4) including pressure, temperature, dynamic extraction time and modifier was performed to get the optimal conditions. Extract 1 was obtained by the optimal extraction condition 1: pressure=35 MPa, T=45 degrees C, dynamic extraction time=2.0 h and V(modifier (MeOH))=0% as guided by the index 1: the free radical scavenging activities in vitro against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethyl-benzthiazoline-6-sulfonic acid) diammonium salt (ABTS). Extract 2 obtained by the optimal extraction condition 2: pressure=25 MPa, T=55 degrees C, dynamic time=2.5h and V(modifier (MeOH))=20% was guided by the index 2: the yield of the volatiles. The results showed that extract 1 possessed stronger antioxidant activity (EC(50)=32.01 microg/ml to DPPH and 50.90 microg/ml to ABTS(+)) than the extract 2 (EC(50)=95.62 microg/ml to DPPH and 99.78 microg/ml to ABTS(+)). Subsequently, the chemical compositions of the two extracts were identified by gas chromatography-mass spectrometry. Forty-six compounds were identified from extract 1, and the total volatile consisted of hydrocarbon (49.65%), aldehyde (16.66%), fatty acid (22.38%), terpene (9.04%) and little alcoholic. From extract 2, 32 compounds were identified, in which hydrocarbon, aldehyde, fatty acid and terpene possessed 58.21%, 5.97%, 13.19% and 21.79%, respectively. This is the first report of using SFE to extract the volatiles from P. Villosa Juss (a wild vegetable and medicine plant) and first time to systematically evaluate the volatiles' antioxidant activity and chemical composition.