Ethyl Acetate Ether Research Articles

The performance of Adsorbing and Removing gaseous acetic acid by activate carbon

Currently, gaseous molecular contaminants (acetic acid) is one of the main factors that cause defects in semiconductors and wafers, reduce product yields in high-tech process plants. Propylene Glycol Monomethyl Ethyl Ether Acetate (PGMEA) is a versatile solvent with many applications. Solvents used in the solder mask process in the manufacture of printed circuit boards (PCBs). The diluent in photoresist and edge bead removers used in semiconductor and wafer fabrication is PGMEA, which forms acetate contaminants through an acid-catalyzed hydrolysis reaction. The concentration standard of acetic acid pollutants in clean rooms is 1ppb.In order to protect the expensive optical components, the acetic acid generated by PGMEA needs to be controlled.For this purpose, the activated carbon filter in the intake filter prevents acetic acid from contaminating the components and corroding the material. In this study, we used the commercially available activated carbon fabricated filter to adsorption of acetic acid. The effect of adsorption under different face velocity (0.03/0.06/0.09 m/s) and initial acetic acid concentrations (4/6/8/10 ppm) were measured according to the principle of ASHRAE 145.1standard. The experimental data are also evaluated for adsorption performance, adsorption capacity, kinetic model of acetic acid adsorption process, and isothermal model of acetic acid adsorption process.The results of the acetic acid adsorption experiment show that MM3000 activated carbon has the highest adsorption capacity and the longest adsorption saturation time than KPL activated carbon. The higher the inlet acetic acid concentration at a fixed wind speed, the shorter the saturation time and the higher the adsorption capacity; the faster the wind speed at a fixed acetic acid concentration, the shorter the saturation time and the higher the adsorption capacity.The Langmuir (R2) of the MM3000 sample is higher than the Freundlich’s coefficient of determination (R2), which indicates that the adsorption phenomenon of the MM3000 sample is more suitable to be described by the Langmuir isothermal adsorption mode, which is the adsorption of a single molecular layer on a homogeneous surface. The Freundlich R2 of the KPL sample is higher than the Langmuir’s coefficient of determination (R2), which means that the adsorption phenomenon of this KPL sample is more suitable to be described by the Freundlich isothermal adsorption mode, and it is a case of adsorption of multiple layers on an inhomogeneous surface. The adsorption of MM3000 activated carbon and KPL activated carbon is more suitable to be described by the proposed second-order adsorption kinetic model, which is a phenomenon of chemisorption.

A novel off-line multi-dimensional high-speed countercurrent chromatography strategy for preparative separation of bioactive neolignan isomers from Piper betle. L

Separation and purification of naturally occurring isomers from herbs are still challenging. High-speed counter-current chromatography (HSCCC) has been applied to isolate natural products. In this study, an off-line multi-dimensional high-speed counter-current chromatography (multi-D HSCCC) strategy was developed utilizing the in situ concentration technique with online storage recycling elution to rapidly separate bioactive isomeric neolignans from chloroform-partitioned samples of the plant Piper betle L. In the procedure, the crude sample (105 mg) was implemented using the online storage recycling technique in a two-phase solvent system composed of petroleum ether-ethyl acetate–methanol-water (7: 5: 12: 3), which first simply afforded a neolignane kadsurenone (1, 5.3 mg) and its epimer (-)-denudatin B (2, 6.4 mg). Then, the remains fr a was subjected to the second-dimensional HSCCC elution using the in situ concentration technique with online storage recycling technique in another solvent system of petroleum ether-ethyl acetate–methanol–water (5: 5: 11, 15). As a result, kadsurenin I (3, 0.6 mg) and its regioisomer pibeneolignan C (4, 5.0 mg), together with the fractional remaining fr b and fr c, were obtained. Thirdly, the fr c was reloaded to allow the HSCCC for recycling elution with the former solvent system employing the in situ concentration strategy and yielded a pair of epimers, (7R,8S,1′S)-1′-allyl-5-methoxy-8-methyl-7-piperonyl-7,8,3,6-tetrahydro-2-oxobenzofuran (5, 10.2 mg), and 3-epi-(-)-burchullin (6, 2.6 mg). Finally, the three pairs of less amount and the structurally similar isomers 1–6 were isolated from the crude fraction of P. betle with a high HPLC purity of over 95.0 % for compound 2, 4-6 and 92.5 % for compound 1, 91.0 % for 3, while the purity of 1 and 3 in 1H NMR were 89.9 % and 91.1 %, respectively. The whole isolation process was quick and efficient. Compounds 1, 2, 4 and 5 showed significantly synergistic activities combining several antibiotics against five drug-resistant Staphylococcus aureus with FICIs from 0.156 to 0.375. This novel off-line multi-dimensional HSCCC strategy could be broadened to application for the rapid separation of complex natural products.

Review of available “extraction + purification” methods of natural ceramides and their feasibility for sewage sludge analysis

Natural ceramide, a biologically active compound present in plants, has been used widely in food, cosmetics, and pharmaceutical industries. Abundant ceramide has been detected in sewage sludge, which has inspired the idea to recycle ceramide from it. Therefore, the methods of extracting, purifying, and detecting ceramides from plants were reviewed, with the aim to establish methods to get condensed ceramide from sludge. Ceramide extraction methods include traditional methods (maceration, reflux, and Soxhlet extraction) and green technologies (ultrasound-assisted, microwave-assisted, and supercritical fluid extraction). In the past two decades, more than 70% of the articles have used traditional methods. However, green extraction methods are gradually improved and showed high extraction efficiency with lower solvent consumed. The preferred technique for ceramide purification is chromatography. Common solvent systems include chloroform-methanol, n-hexane-ethyl acetate, petroleum ether-ethyl acetate, and petroleum ether-acetone. For structural determination of ceramide, infrared spectroscopy, nuclear magnetic resonance spectroscopy, and mass spectrometry are used in combination. Among quantitative analysis methods for ceramide, liquid chromatography-mass spectrometry was the most accurate. This review concludes that with our prilemenary experiment results it is feasible to apply the plant "extraction + purification" process of ceramide to sludge, but more optimization need to be performed to get better results.

Bioactivity-Guided High Performance Counter-Current Chromatography and Following Semi-Preparative Liquid Chromatography Method for Rapid Isolation of Anti-Inflammatory Lignins from Dai Medicinal Plant, Zanthoxylum acanthopodium var. timbor.

The development of Dai medicine is relatively slow, and Zanthoxylum has great economic and medicinal value. It is still difficult to obtain medicinal components from the low-polarity parts of Zanthoxylum belonging to Dai medicine. In this study, we introduced one simple and quick strategy of separating target compounds from the barks of Z. acanthopodium var. timbor by high-performance countercurrent chromatography (HPCCC) with an off-line anti-inflammatory activity screening mode. The development of this strategy was based on the TLC-based generally useful estimation of solvent systems (GUESS) method and HPCCC in combination. This paper presented a rapid method for obtaining target anti-inflammatory compounds. Three lignins were enriched by HPCCC with an off-line inhibition mode of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 macrophage cells, using petroleum ether-ethyl acetate-methanol-water (3:2:3:2) as the solvent system. The results showed that this method was simple and practical and could be applied to trace the anti-inflammatory components of the low-polarity part in Dai medicine.

How Extraction and Purification Affect MALDI-TOF MS Characterization of Mangrove Condensed Tannins, An Ecologically Important Secondary Metabolites in Coastal Wetland Ecosystem

Mangrove plants are rich in tannins, especially condensed tannins (CTs), which play an important role in biogeochemistry in coastal wetland ecosystem due to their functions of binding nutrients and heavy metal chelation. This study aims to obtain authentic chemical structures of mangrove CTs by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Four organic solvents (n-hexane, ether, chloroform, and EtOAc (ethyl acetate)) were used for extraction tests and three purification methods (Method 1, Sephadex LH-20 absorbed tannins, and nontannins fraction were washed by 50% methanol (mp) solution; Method 2, Sephadex LH-20 absorbed tannins and nontannins fraction were washed by 100% ethanol (ep), and released in 70% acetone solution; and Method 3, Yb3+ selectivity precipitated tannins) were conducted to investigate their influences on the characterization of CTs from two mangrove species, Bruguiera gymnorhiza and Kandelia obovata. The results showed that (1) EtOAc was used as an extraction solvent, leading to unauthentic structural properties of CTs; (2) the distribution patterns of the polymers in mangrove CTs purified with 50% methanol elicited the least different trends with those of CTs in the two mangrove crude extracts, and the lower oligomers (dimmer-hexamer) and higher polymers were lost during purification of CTs by 100% ep. Therefore, based on the toxicity and price of solvents, the crude CTs from mangrove plants can be extracted with n-hexane or ether to remove lipid and pigment impurities and then purified with 50% methanol, which is a complete set of methods to obtain completely authentic structural information of mangrove CTs. This study can offer more accurate structural information of mangrove CTs and new insights for the conservation of mangrove living environments for follow-up research.

Simultaneous Determination of the Content of Isoimperatorin, Imperatorin, Oxypeucedanin, Xanthotoxol and Byakangelicin in Angelica dahurica by HPTLC Scanning.

In this study, we established a new rapid, simple and low cost method for the determination of coumarin components in Angelica dahurica using high-performance thin-layer chromatography (HPTLC) based on the standards of the Chinese Pharmacopoeia for the analysis of isoimperatorin, imperatorin, oxypeucedanin, xanthotoxol and byakangelicin. The coumarins in A. dahurica were extracted with solvent methods, and linear ascending development was carried out in a twin trough glass chamber saturated with petroleum ether-ethyl acetate (3:2, v/v). The plate was dried and analyzed by HPTLC scanner at 254nm. The five coumarin components have achieved good separation, clear and satisfactory resolution with the Rf values of 0.84, 0.69, 0.64, 0.57 and 0.19 for isoimperatorin, imperatorin, oxypeucedanin, xanthotoxol and byakangelicin, respectively. The content of five coumarins were 0.282, 0.626, 0.393, 0.066 and 0.144, respectively. In addition, the calibration range was constructed in the range 0.8-4.0μg/spot; the limit of detection and limit of quantification, precision, repeatability and recovery were stably and good. This study indicated that the HPTLC scanning could be used for the determination of multiple components in A. dahurica.

Isolation and characterization of 3,3′-di-O-methyl ellagic acid from the root bark of Afzelia africana and its antimicrobial and antioxidant activities

Afzelia africana is a tropical plant with extensive economic and medicinal potential. The plant is reported to have vast secondary metabolites and has been utilized for the treatment of various diseased conditions ethnomedically but no reports of compounds have been isolated from the plant. The study aimed to isolate bioactive compounds from the bark, purify and identify them using column chromatography, spectroscopic and spectrometric methods, and determine their antimicrobial and antioxidant activities. Antimicrobial and antioxidant assays were performed on the identified compound. Column chromatographic fractionation of the methanol extract of the bark of the plant using a solvent system of petroleum ether-ethyl acetate (95:5, 90:10, 85:15, and 70:30) afforded several fractions which were pooled together based on a thin-layer chromatographic profile. The fractions from the solvent system of 85:15 after sub-fractionation using petroleum ether-ethyl acetate (70:30) afforded a 20 mg yellow powder. The isolate was characterized based on 1H, 13C, DEPT-135, HSQC, HMBC, and ESI-MS and unequivocally identified as 3,3′-di-O-methyl ellagic acid. The antimicrobial activity of the compound was tested against Streptococcus mutans, Staphylococcus aureus, Escherichia coli, methicillin-resistant Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumonia, Pseudomonas aeruginosa, Salmonella typhi, and Candida albicans 1 and 2. The compound recorded percentage inhibitions ranging from 40-100% and 0-30% at 6.25-1.56 and 0.78–0.20 mg/mL, respectively. The highest level of inhibition was reported for Escherichia coli (35.0-92.5 %), Salmonella typhi (100%), and Candida albicans 1 (100%) over the concentration range of 6.25-0.20 mg/mL. The compound also reported a broad spectrum of bactericidal activity against all the microbial strains with corresponding MBC/MIC ratios of ≤ 4. The IC50 values for the compound in the ABTS and DPPH scavenging assays were 5.76 ± 0.06 and 9.97 ± 0.27 µg/mL, respectively. This paper reports for the first time the identification of 3,3′-di-O-methyl ellagic acid from the bark of Afzelia africana.

Pengujian Efek Hipoglikemik Fraksi Petroleum Eter dan Etil Asetat Daun Dandang Gendis (Clinacanthus nutans (Burm. F.) Lindau)

The investigation had been done about hypoglycaemic effect from Clinachanthus nutans (Burm f.) Lindau extract, which in petroleum ether extract and ethyl acetate extract, that used Glucose Method Tolerance for Mice. The extract of Clinachanthus nutans (Burm f.) Lindau leave was carried out by masseration and using ethanol 80% as solvent, and gradually fractination for ethanol extract with petroleum ether and ethyl acetate solvent. Further, the glucose tolerance had been done for petroleum ether fraction and ethyl acetate. The mice was fasting during 17 hours and the blood glucose level and weight of mice was measured and given the 50% glucose liquid with dose 4 mg/kg bw. After 30 minutes the blood glucose level can be measure again. Divided the mice to 6 group, Group I: control (CMC 0,5% dose 1 % bw); Group II until Group V given the petroleum ether fraction and ethyl acetate fraction with dose 15, 30, 45 dan 60 mg/kg bw; Group VI: given the Glibenclamid suspension dose 1 mg/kg bw as equal. Fixed blood glucose level of mice after 60, 90, 120, 150 and 180 minutes to have use of glucometer (EZ Smart). The result showed that petroleum ether extract doesn’t have hypoglycaemic effect, but in dose 45 and 60 mg/kg bw has given hypoglycaemic effect which to get near Glibenclamid suspension in dose 1 mg/ kg bw with blood glucose level decrease 0,05 (ɑ=0,05).

An imperical analysis of various extracts of Bacopa Monnieri towards antibacterial and antifungal activities

Bacopa monnieri was also known as “Brahmi.” Theses plant has been considered as medicinal plants in Ayurvedic systems for centuries. This present study was carried out to evaluate the antibacterial and antifungal properties of ethanolic, diethyl ether, ethyl acetate, and aqueous extracts of B. monnieri. Agar disc diffusion tests were carried out to determine the antimicrobial effects of ethanolic, diethyl ether, ethyl acetate and aqueous extracts of B. monnieri against Gram-positive (Staphylococcus aureus), Gram-negative (Escherichia coli) bacterial strains and antifungal strains (Aspergillus flavus, and Candida albicans). Among the various extracts, diethyl ether extracts of B. monnieri has an antibacterial potency against Staphylococcus aureus (gram positive), and ethyl acetate extract showed effects on E. coli (gram negative) at higher concentrations of 300 μg mL-1. The ethanolic extract has potent antifungal activity against the fungus (Aspergillus flavus, and Candida albicans) compared to diethyl ether and ethyl acetate-ether. Both extracts (diethyl ether and ethyl acetate) has a minimum antifungal effect while these extracts showed more inhibitory effects on tested bacteria.

Isolation and Structure of the New Sesquiterpene Lactone 3-oxo-10β-hydroxy-5,7α(H),4,6β(H)-guai-1,11(13)-diene-6,12-olide

The article presents the results of a chemical study of Tanacetopsis pjataevae, which is an endemic plant in Ka-zakhstan. The number of extractive substances was obtained by extraction with chloroform from the air-dry crushed above-ground part of the plant collected in the flowering phase. Isolation of compounds was carried out by column chromatography on a column of silica gel brand KSK at a ratio of sum - carrier = 1:20. A colorless crystalline substance of the composition C15H18O4 with m.p. 189–191°C (recrystallized from diethyl ether) was found when the column was eluted with a mixture of petroleum ether-ethyl acetate (87.5:12.5). The structure of the obtained new compound (3-oxo-10β-hydroxy-5,7α(Н),6β(Н)-guai-1,11(13)-diene-6,12-olide) was estab-lished based on IR, NMR analysis and mass spectra. The spatial structure was determined by the X-ray diffrac-tion method. It was established that the 3-oxo-10β-hydroxy-5,7α(Н),6β(Н)-guai-1,11(13)-diene-6,12-olide mole-cule in the crystal is disordered over two conformational states in the 6 :4 ratio. The stability of these conformers was confirmed by semi-empirical quantum-chemical calculations. It was established that the difference in the heat of formation of two conformers was 6.3 kJ/mol for a free molecule.

Erteng Tongbi Decoction ameliorates collagen-induced arthritis in mice via modulating T cell differentiation and cytokines balance

Ethnopharmacological relevanceHerbs have been commonly used for the treatment of rheumatoid arthritis (RA). It has been verified that Erteng Tongbi Decoction has good therapeutic effects on RA, while, relatively few studies on the relationship between its components and anti-rheumatoid efficacy were carried out.Aim of the study: To discuss the anti-RA effects of Erteng Tongbi Decoction on collagen-induced arthritis (CIA) in mice and the influence of T cell differentiation and cytokines balance. Materials and methodsSeparate researches on the two traditional Chinese medicines of the Erteng Tongbi Decoction were conducted. First, a murine peritoneal macrophage model was established, and then the cytokines levels and macrophage maturity were measured to select the best extraction solvent. Furthermore, ethanol extracts were partitioned successively with four kinds of solvents, and the anti-inflammatory parts were selected by the same vitro model. Subsequently, mice were arbitrarily divided into control, CIA model, positive control, effective parts alone or in combination. After 20 days of oral administration, the weight, hind paw volume, rheumatism index value, and the pathological changes were checked to assess the obvious level of arthritis. Furthermore, the levels of IL-6, TNF-α, IL-10, and IL-17A in serum and the balance of Th17/Treg and Th1/Th2 cells in spleen and mesenteric lymph nodes (MLN) was detected. Finally, the major active constituents were identified. ResultsIn vitro, the anti-inflammatory effects of ethanol extracts was much better than water extract. In addition, the effective parts of Celastrus orbiculatus Thunb. ethanol extract were petroleum ether parts and dichloromethane parts. The effective parts of Spatholobus suberectus Dunn. ethanol extracts was petroleum ether parts and ethyl acetate parts screened. In vivo, effective parts compatibility could inhibit the progression of inflammation by modulating T cell differentiation and cytokines balance. Constituent analysis revealed that effective parts contained sesquiterpenes alkaloids, phenolic acids, and flavanols. ConclusionsErteng Tongbi Decoction could notably ameliorate CIA mice by modulating T cell differentiation and cytokines balance and support its application in folk medicine.

Metabolite Profiling of Peltophorum africanum Sond. & Saraca indica L. Leaves via HR-UPLC/PDA/ESI/MS Analysis and Assessment of their Anti-Diabetic Potential

This study aimed to screen different extracts (E) such as total ethanol (TE), petroleum ether (PE) chloroform (CH), ethyl acetate (EA) and methanol (AM) extracts of Peltophorum africanum Sond. (PA) and Saraca indica L. (SI) leaves (family fabaceae) for their in-vitro antidiabetic activity using α-amylase inhibition assay. The extracts that showed remarkable in vitro activity were further subjected to in vivo anti-diabetic assessment using streptozotocin-induced diabetes model in experimental animals where serum glucose, C-peptide, liver glycogen content in addition to lipid peroxide level in both serum and liver were estimated biochemically in normal and diseased rats. The average percent of weight change and kidney to body weight ratio percent were calculated for all animal groups. Histopathological examination of pancreas, liver and kidney sections isolated from all animals was carried out. UPLC/MS/MS analysis of TEE of PA and SI for chemical investigation was performed. Results of the in vitro anti diabetic activity revealed that EAE, PEE& TEE of PA and TEE & EAE of SI possessed the highest inhibitory activity as compared to acarbose. In vivo antidiabetic activity of the selected extracts revealed that animal groups treated daily with EAE of PA and SI exhibited a significant improvement in carbohydrate metabolism and lipid peroxide level, with superior effect in comparison with that of TEE and PEE of both plants. Histopathological findings showed marked protection particularly in sections isolated from animals treated with EAE of PA. UPLC/MS/MS analysis of TEE of both plants identified 46 metabolites belonging to various classes. It could be suggested that active extracts of both plants could be considered as potential natural antioxidant and anti-diabetic agents.

Evaluation and characterization of a new method of extracting bark wax from Pinus radiata D. Don

The bark of Pinus radiata D. Don is a bioresource of great worldwide abundance. While various forms of use have been studied, it is still a little-used bioresource. Due to its great accumulation, significant solid emissions of this residue generate environmental problems such as changes in soil chemistry, ecological problems such as the alteration of arthropod communities and fire risk. The opportunity to take advantage of this bioresource could be in its wax content, which could be a replacement for the main raw materials used in the production of cosmetics. These currently correspond to petroleum-derived substances, such as petroleum jelly, paraffin, or mineral oil. The importance of replacing these raw materials is that several studies report that they are the main causes of human skin diseases, such as chemical hypersensitivity syndrome and allergic contact dermatitis. This study seeks to prove that lipophilic extracts (waxes) from pine bark can replace petroleum-derived raw materials used in cosmetics. To achieve this, pine bark at drying conditions was characterized, and the performance of wax extraction by various treatments was studied. The density, viscosity, melting point, and solubility in culture media of the obtained waxes were determined. The waxes were chemically characterized by FT-IR and GCMS analysis. The results reveal that the maximum moisture of the bark is 14.54 %, the best extraction yields are obtained by using water at 120 °C and 1.2 atm, and petroleum ether (3.12 %), alkaline hydrolysis 1 mol L−1 (NaOH) and petroleum ether (3.53 %) ethyl acetate (3.23 %). Values were close to the reference study using the rapid lipid extraction method. The density of the wax is 0.845 g mL−1 and its viscosity of 530 cP (24 °C), and the melting point varied according to the extractive treatment at between 25 and 40 °C. Solubility tests made it possible to determine that the 10/50/1000 μL ratio of modified Eagle Dulbecco wax/dimethylsulfoxide/medium allows homogeneous solubilization of the wax without the presence of precipitates. Chemical characterization identified typical functional groups of plant-based waxes such as long-chain alkanes, alkyls, methyl groups, esters, and carbonyls, with the most abundant fatty acids being C:22 and C:24.

Study on Characteristic Separation, Identification and Antimicrobial Activity of Main Compounds from the Rhizomes of Alpinia Allughas.

Alpinia allughas Rosc. is a Zingiberace herb has been used in this study. A systematic study has been done for the chemical constituents of this plant and bioactive compounds responsible for the medicinal properties were identified by the chemical examination of rhizome extract. Also the antimicrobial properties of the active compounds has also been studied. To carryout the studies the extract of crushed dried rhizomes of A. allughas was partitioned with chloroform solvent (Hexane, CHCl3, EtOAc, BuOH) system. Fractions are subjected to column chromatography on silica gel or alumina. Column was packed in pure petroleum ether and ran with increasing percentage of ethyl acetate as eluent. The compounds were fractionated and isolated from petroleum ether and ethyl acetate with different polarities 1%, 2% 3% 4%, 5%, 8%,10% increasing order with help of column chromatography and thin layer chromatographic technique. The chloroform extract of rhizomes of Alpinia allughas showed the presence of five prominent and a number of other spots on thin layer chromatography (TLC). All the fractions were collected and distilled over water bath. TLC of each fraction was regularly checked in various combinations of petroleum ether-ethyl acetate and chloroform-methanol. Compounds A, B, and C were isolated at different combinations of petroleum ether and ethyl acetate on silica gel for that the column extract was subjected to column chromatography over silica gel. Elemental analysis were carried out for each extracted compounds followed by various spectral analysis including Infra red, 1H NMR, 13C NMR and mass spectroscopy. Finally the antimicrobial properties of all the active compounds extracted was studied against the three different bacterial strains.

ФЛАВОНОИДЫ РАСТЕНИЙ POPULUS BALSAMIFERA И ИХ БИОЛОГИЧЕСКАЯ АКТИВНОСТЬ

The work is devoted to the chemical studying of the composition of flavonoids of Populus balsamifera, the isolation of individual compounds, and the establishment of their structure. Balsamic poplar plants are a promising source of many biologically active substances, and in particular, flavonoids. From the buds of Populus balsamifera L. identified four flavonoids with antifungal, antimicrobial antioxidant properties and hepatoprotective activity. Data of flavonoids were isolated by extraction on the soxlet apparatus with 95% ethanol by triple thermal extraction at a temperature of 60 °C, followed by thickening on a rotary evaporator. For isolation from the buds of balsamic poplar, the resulting extract was chromatographed on a column with silica gel of the KSK brand 0.31-0.63 microns, using petroleum ether as eluents petroleum ether-ethyl acetate in various ratios and ethyl acetate. The structure of the isolated compounds was determined by IR, UV, NMR 13C, 1H spectroscopy. The biological activity of the isolated flavonoids was also studied.

Development of ultrasound-assisted centrifugal extraction and online solvent concentration coupled with parallel countercurrent chromatography for the preparation of purified phytochemicals: Application to Lycium ruthenicum

To improve the preparation efficiency of natural products, new techniques for extraction and concentration of natural products have been established. Based on this, an on-line technology to improve the yield and preparation efficiency of natural products have been established. In this study, a novel method to extract natural products from crops and plants, termed ultrasound-assisted centrifugal extraction (UACE), was developed as a supplement to a new online solvent concentration (OSC) technique. These techniques were coupled with parallel countercurrent chromatography (PCCC) and evaluated in the automated preparation of phytochemicals from Lycium ruthenicum. The UACE device comprises an extraction chamber and a solution separation chamber and offers the advantages of higher extraction efficiency, fewer impurities, and conduciveness to sample processing. The OSC device comprises a spray nozzle, concentrating cylinder, and hot-blast air nozzle. The mechanical parameters of the UACE and OSC were optimized, and the operation mode of online UACE combined with OSC and PCCC was described. Raw plant materials were extracted with a two-phase extractant comprising petroleum ether‒ethyl acetate‒ethanol‒water (2:2:1:6, v/v/v/v), and the aqueous and organic phases were then concentrated by OSC. After extraction and online concentration, the concentrate was separated. During PCCC separation, the on-line extraction, and concentration were still conducted. When the first cycle of the UACE/OSC/PCCC was completed, the second cycle was initiated, and so on. As a result, six target compounds with purities exceeding 97.03 % (high performance liquid chromatography detection at 250 nm) were successfully separated using the countercurrent chromatography solvent systems comprising n-heptane‒ethyl acetate‒acetonitrile‒water (20:4:17:1, v/v/v/v) and n-butanol–ethyl acetate–water (55:21:70, v/v/v). Compared with conventional extraction methods, the proposed method offers the advantages of efficiency, automation, high-purity separation of the analytes, and systematic preparation of natural products from crops.

Isolation and Purification of an Antibiotic Polyketide JBIR-99 from the Marine Fungus <i>Meyerozyma guilliermondii</i> by High-Speed Counter-Current Chromatography

JBIR-99 is a natural compound isolated from marine source which possesses strong antibiotic activity. An efficient approach using a combination of size exclusion chromatography with a Sephadex LH-20 and high-speed counter-current chromatography (HSCCC) has been successfully developed for the isolation and purification of a polyketide from the solid-state fermentation of Meyerozyma guilliermondii, a strain of marine fungus isolated from Indian Ocean. The active compound was isolated with purity >95% by HSCCC using an optimized solvent system composed of petroleum ether–ethyl acetate– 95% ethanol–water (5: 3: 5: 3, v/v/v/v) after size exclusion chromatography. This compound was successfully purified in the quantity of 68 mg from 120 mg of the crude extract. The structure of JBIR-99 was elucidated and assigned by 1D, 2D NMR spectroscopic, and positive HRESITOFMS. Moreover, the relative configuration of compound JBIR-99, displaying a quite complex multi-ring structure, is determined by X-ray crystallography for the first time. The purification method developed for JBIR-99 will facilitate the further investigation and development of this antibiotic agent as a lead compound. Furthermore, it is suggested that the combination of size exclusion chromatography and HSCCC could be more widely applied for the isolation and purification of polyketides from marine fungi.

Qualitative and quantitative analyses of aloe-emodin, rhein, and emodin in qi yin granules by high-performance thin-layer chromatography

The aim of this study was to perform qualitative and quantitative analyses of aloe-emodin, rhein, and emodin in three prepared samples of compound qi yin granules by high-performance thin-layer chromatography (HPTLC) and to establish an analytical method. TLC was used to qualitatively analyze the three major components of the compound: aloe-emodin, rhein, and emodin. HPTLC was performed to determine the contents of the three components. HPTLC analysis showed that using Anhui Liangchen high-efficiency silica gel G plate was the optimal stationary phase and the upper layer solution of a petroleum ether–ethyl acetate–formic acid (15.5:5:1, V/V) mixed solution was the optimal developing agent. The composition of the samples for testing was basically the same, but the content was different. In summary, this study used HPTLC to qualitatively and quantitatively analyze aloe-emodin, rhein, and emodin in compound qi yin granules. It can lay the foundation for improving the quality control and standards of compound qi yin granules.

Spray-Drying Microencapsulation of High Concentration of Bioactive Compounds Fragments from Euphorbia hirta L. Extract and Their Effect on Diabetes Mellitus.

The present study was performed to spray-dry the high concentration of bioactive compounds from Euphorbia hirta L. extracts that have antidiabetic activity. The total phenolic content (TPC) and total flavonoid content (TFC) of four different extracts (crude extract, petroleum ether extract, chloroform extract and ethyl acetate extract) from the dried powder of Euphorbia hirta L. were determined using a spectrophotometer. After that, the fragment containing a high number of bioactive compounds underwent spray-dried microencapsulation to produce powder which had antidiabetic potential. The total phenolic content values of the crude extract, petroleum ether extract, chloroform extract and ethyl acetate extract were 194.55 ± 0.82, 51.85 ± 3.12, 81.56 ± 1.72 and 214.21 ± 2.53 mg/g extract, expressed as gallic acid equivalents. Crude extract, petroleum ether extract, chloroform extract and ethyl acetate extracts showed total flavonoids 40.56 ± 7.27, 29.49 ± 1.66, 64.99 ± 2.60 and 91.69 ± 1.67 mg/g extract, as rutin equivalents. Ethyl acetate extract was mixed with 20% maltodextrin in a ratio of 1:10 to spray-dry microencapsulation. The results revealed that the moisture content, bulk density, color characteristic, solubility and hygroscopicity of the samples were 4.9567 ± 0.00577%, 0.3715 ± 0.01286 g/mL, 3.7367 ± 0.1424 Hue, 95.83 ± 1.44% and 9.9890 ± 1.4538 g H2O/100 g, respectively. The spray powder was inhibited 51.19% α-amylase at 10 mg/mL and reduced 51% in fast blood glucose (FBG) after 4 h treatment. Furthermore, the administration of spray powder for 15 days significantly lowered the fast blood glucose level in streptozotocin-diabetic mice by 23.32%, whereas, acarbose—a standard antidiabetic drug—and distilled water reduced the fast blood glucose level by 30.87% and 16.89%. Our results show that obtained Euphorbia hirta L. powder has potential antidiabetic activity.

Isolation of Kaempferol from Vietnamese Ginkgo biloba Leaves by Preparative Column Chromatography

The aim of this research was to develop a simple procedure to isolate kaempferol from Ginkgo biloba leaves extract. Flavonoids present in Ginkgo biloba leaves were extracted by 96 % ethanol. These flavonol glycosides which were hydrolyzed in the presence of HCl to convert to aglycones. The flavonol aglycones were extracted by the hydrolysis of solution with ethyl acetate which was evaporated to dryness under reduced pressure to obtain concentrated flavonol aglycones (C2). Flavonol aglycones were then purified by preparative column chromatography with a mobile phase composed of petroleum ether-ethyl acetate to acquire fraction C3. The recrystallization of fraction C3 in acetone realizes to have an amorphous sediment as fraction C4 that was supposed to be a mixture of kaempferol, quercetin and isorhamnetin. Kaempferol in this sediment was purified by column chromatography with a mobile phase composed of CHCl3-MeOH to achieve a fraction denoted as fraction C5. The isolated fraction C5 was assigned by its purity and structure by thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and spectroscopic data analyses.