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Alkaline ionic liquid aqueous solutions were used to extract biphenyl cyclooctene lignans derivatives, and hydrolyze to the free-state biphenyl cyclooctene lignans simultaneously from Schisandra chinensis by microwave-assisted heating. The hydrogen bonds formatted between ionic liquid and water molecular attacks the amorphous region of cellulose. Selective heating by microwave produce the more polar regions, which results in swelling and fragmentation of raw materials near the hot spots. Therefore, ionic liquid-microwave-assisted extraction method of free-state biphenyl cyclooctene lignans was set up. The solid residue after treatment was characterized by infrared spectroscopy and scanning electron microscopy, which showed that cellulose, hemicellulose, and lignin were removed partially. The water content of ionic liquid solution affected its viscosity and diffusivity, and in turns the extraction efficiency of lignans. The IL solutions with different mole fractions of IL were detected by FTIR and Raman spectroscopy, the result shows that IL solutions with higher water contents (>0.6) won't form clusters. The optimum hydrolysis conditions were 0.2 g of ionic liquid catalyst per 5.0 g of S. chinensis fruits, a microwave irradiation power of 600 W, and heating time of 12 min, which gave a yield of free-state biphenyl cyclooctene lignans of 4.12±0.37 mg g-1. Besides, a hydrolysis mechanism of ester-bond biphenyl cyclooctene lignans and decreasing "biomass recalcitrance effect" by ionic liquid microwave-assisted method was proposed., Competing Interests: The authors have declared that no competing interests exist.

A homogenate-assisted vacuum-cavitation extraction (HVE) method with a "green" solvent (a deep eutectic solvent, DES) was developed to extract phenolic compounds from rattan ( Calamoideae faberii ). In this study, the optimum molar ratio of choline chloride (ChCl) and ethylene glycol (EG) was 1:3, the optimum volume ratio of ChCl-EG:H₂O was 6:4, the solid-liquid ratio of HVE was 1:15, and the extraction time of homogenate and vacuum-cavitation were 2.0 min and 25 min, respectively. Under the optimum parameters of HVE, the extraction yield of total phenolic content with ChCl-EG solution was 6.82 mg/g. The higher total phenolic content was detected in fruit tissues (seeds 81.24 ± 1.55 mg/g, episperm 43.21 ± 0.87 mg/g, and arillus 38.47 ± 0.74 mg/g), followed by in leaves (sheath 19.5 ± 0.38 mg/g and blade 17.81 ± 0.33 mg/g). In addition, the content of specific phenolic compounds in aqueous and DES extracts was determined. Chlorogenic acid was the most abundant phenol in most organs of the rattan plant. Gallic acid was mainly distributed in the arillus; protocatechuic acid was mainly distributed in the arillus, sheath, and blade; protocatechuic aldehyde was mainly distributed in the blade, seed, and sheath; (+)-catechins were mainly distributed in the episperm, seed, and sheath; and epigallocatechin gallate was mainly distributed in the blade. The recovery rates of gallic acid, protocatechuic acid, protocatechuic aldehyde, (+)-catechins, chlorogenic acid, and epigallocatechin gallate were 93.77%, 94.09%, 97.32%, 97.83%, 94.41%, and 92.47%, respectively, by AB-8 resin.

Sustainable development of renewable resources is a major challenge globally. Biomass is an important renewable energy source and an alternative to fossil fuels. Pyrolysis of biomass is a promising method for simultaneous production of biochar, bio-oil, pyroligneous acid (PA), and gaseous fuels. The purpose of this study was to investigate the pyrolysis process and products yields of Schisandra chinensis fruits with different pyrolysis powers. The obtained PA was extracted with organic solvents, including ethyl formate, dichloromethane, methanol and tetrahydrofuran. The antioxidant activities, including the free radical scavenging activity and ferric reducing power, of the PA extracts were investigated. The synthetic antioxidants butylated hydroxyanisole and butylated hydroxytoluene were used as positive controls. A dichloromethane extract of PA showed excellent antioxidant properties compared to the other extracts. The chemical compositions of the PA extracts were determined by GC-MS, and further proved that the dichloromethane extract had the best antioxidant characteristics among the extracts tested.

Hops (Humulus lupulus), a main ingredient in beer, are valued as a source of bitter flavour and biologically active polyphenols. We treated immature hop cones with prohexadione-calcium (Pro-Ca), a flavanone-3-hydroxylase (F3H) inhibitor, to perturb the flavonoid pathway, and conducted a targeted analysis of 29 compounds from the phenolic acid, flavonoid, and terpenophenolic pathways, using photodiode array (UHPLC-PDA), and time of flight mass spectrometry (LC-TOF-MS) analysis. Hop cones were analysed over four stages of development spanning 22days following Pro-Ca treatment. The content of terpenophenolics as well as metabolic precursors upstream from F3H significantly increased, and levels of flavonoid products downstream from F3H decreased. The methods developed here serve to compliment flavour analysis of polyphenol rich foods, and our results suggest ways to improve upon traditional agricultural methods to produce hops with altered chemical profiles., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

In this work, a multivariate study based on Box-Behnken Design was used to evaluate the influence of three major variables affecting the performance of the extraction process of Schisandra chinensis anthocyanins. The optimum parameters were 5.5 h extraction time; 1:19 solid-liquid ratio and 260 r/min stirring rate, respectively. The extraction yield of anthocyanins was 29.06 mg/g under the optimum conditions. Moreover, many factors on the impact of heating, ultrasound, microwave treatment and ultraviolet irradiation on content and color stability of anthocyanins from Schisandra chinensis fruit were investigated. The results show that thermal degradation reaction of anthocyanins complies with the first order reaction kinetics, and the correlation coefficient is greater than 0.9950 at 40-80°C. Ultrasound and microwave treatment has little effect on the stability of anthocyanins, and the extraction time of ultrasound and microwave should be no more than 60 min and 5 min, respectively. The anthocyanins degradation effect of UVC ultraviolet radiation is greater than UVA and UVB; after 9 h ultraviolet radiation, the anthocyanins content degradation of UVC is 23.9 ± 0.7%, and the ∆E* was changed from 62.81 to 76.52 ± 2.3. Through LC-MS analysis, the major composition of Schisandra chinensis anthocyanins was cyanidin-3-O-xylosylrutinoside.

Ionic liquid based, ultrasound-assisted extraction was successfully applied to the extraction of phenolcarboxylic acids, carnosic acid and rosmarinic acid, from Rosmarinus officinalis. Eight ionic liquids, with different cations and anions, were investigated in this work and [C(8)mim]Br was selected as the optimal solvent. Ultrasound extraction parameters, including soaking time, solid-liquid ratio, ultrasound power and time, and the number of extraction cycles, were discussed by single factor experiments and the main influence factors were optimized by response surface methodology. The proposed approach was demonstrated as having higher efficiency, shorter extraction time and as a new alternative for the extraction of carnosic acid and rosmarinic acid from R. officinalis compared with traditional reference extraction methods. Ionic liquids are considered to be green solvents, in the ultrasound-assisted extraction of key chemicals from medicinal plants, and show great potential.

Hop (Humulus lupulus L.) inflorescences, commonly known as "hop cones", are prized for their terpenophenolic contents, used in beer production and, more recently, in biomedical applications. In this study we investigated morphological and phytochemical characteristics of hop cones over five developmental stages, using liquid chromatography coupled to time-of-flight mass spectrometry (LC-TOF-MS), and ultrahigh performance liquid chromatography photodiode array detection (UHPLC-PDA) methods to quantitate 21 polyphenolics and seven terpenophenolics. Additionally, we used light microscopy to correlate phytochemical quantities with changes in the morphology of the cones. Significant increases in terpenophenolics, concomitant with glandular trichome development and associated gross morphological changes, were mapped over development to fluctuations in contents of polyphenolic constituents and their metabolic precursor compounds. The methods reported here can be used for targeted metabolic profiling of flavonoids, phenolic acids, and terpenophenolics in hops, and are applicable to quantitation in other crops.

Fruit of the cultivated eggplant species Solanum melongena, Solanum aethiopicum, and Solanum macrocarpon, and wild relatives including Solanum anguivi and Solanum incanum, have a high content of hydroxycinnamic acid conjugates with potential human health benefits. Typically, caffeoylquinic acid esters predominate, and in particular 5-O-(E)-caffeoylquinic acid. By contrast, fruit from accession PI 319855 in the USDA eggplant core collection, unambiguously identified as Solanum viarum by morphological characters, were found to include several major, closely related hydroxycinnamic acid conjugates with much longer C18-HPLC retention times than those of 5-O-(E)-caffeoylquinic acid and other monocaffeoylquinic acid isomers. Four of these compounds were isolated from methanolic extracts of lyophilized fruit tissues by C18-HPLC, and structurally elucidated using (1)H and (13)C NMR techniques and HR-TOF-MS. Isomeric compounds 1 and 2 are composed of 5-O-(E)-caffeoylquinic acid with a malonyl group on the 3- or 4-hydroxyl of quinic acid, respectively, plus a 6-O-sinapoylglucose group 1-O-β-D linked with the 4-hydroxyl on the phenyl ring of the caffeoyl moiety (1β,4β-dihydroxy-3β-carboxyacetoxy- and 1β,3β-dihydroxy-4β-carboxyacetoxy-5α-[[3-[4-[1β-(6-O-(E)-sinapoyl-β-D-glucopyranosyl)oxy]-3-hydroxyphenyl]-(E)-1-oxo-2-propenyl]oxy]cyclohexanecarboxylic acid). Compound 3 has the same structure as 1 and 2 without malonation of quinic acid (1β,3β,4β-trihydroxy-5α-[[3-[4-[1β-(6-O-(E)-sinapoyl-β-d-glucopyranosyl)oxy]-3-hydroxyphenyl]-(E)-1-oxo-2-propenyl]oxy]cyclohexanecarboxylic acid). Compound 4 differs from 3 by methylation of the carboxyl group on quinic acid (methyl 1β,3β,4β-trihydroxy-5α-[[3-[4-[1β-(6-O-(E)-sinapoyl-β-D-glucopyranosyl)oxy]-3-hydroxyphenyl]-(E)-1-oxo-2-propenyl]oxy]cyclohexanecarboxylate). Some features of these four new compounds, such as malonation and the specific linkages between caffeoyl, glucosyl, and sinapoyl moieties, are common in acylated and glycosylated phenylpropanoids, but have not previously been reported in complex derivatives of 5-O-(E)-caffeoylquinic acid.

Highlights: [•] Analyze the pyrolysis process and the pyrolysis products of Rosmarinus officinalis L. [•] Compare the antioxidant effect of different organic extracts of pyroligneous acid. [•] Analyze the compositions of extracts of pyroligneous acid by GC–MS. [Copyright &y& Elsevier]

Abstract: An efficient microwave pretreatment (MP) method was employed to maintain quality of postharvest rosemary leaves. The influence of MP on the contents of carnosic acid (CA) and rosmarinic acid (RA) in rosemary leaves was investigated under four storage conditions (sunlight, shade, −20°C, 55°C). Rosemary leaves after MP (800W, 15min) had much lower degradation rates of CA and RA than those of non-treatment samples during the storage period. Moreover, retentions of CA and RA of pretreated leaves stored in the shade and −20°C were higher than those of 55°C and sunlight. In the pretreatment process, we simultaneously used microwave radiation to extract essential oil. No obvious differences were found in yield or composition between essential oils obtained by MP and hydrodistillation. Thus, MP could be a good method for extracting essential oil and maintaining quality in rosemary and other aromatic herbs. [Copyright &y& Elsevier]

Cavitation hybrid rotation, which was and is still looked upon as an unavoidable nuisance in the flow systems, for extraction processing intensification of active chemical compounds from natural products. In this study, a homogenization-assisted cavitation hybrid rotation extraction method was applied to extract dihydroquercetin (DHQ) from larch ( Larix gmelinii ) wood root. The extraction parameters were optimized in single factor experiments with the DHQ extraction yields as the response values. The optimum conditions were as follows: number of extractions, three; ethanol volume fraction for the extraction, 60%; liquid–solid ratio for homogenization, 10 mL/g; homogenization time, 8 min; liquid–solid ratio for cavitation extraction, 9 mL/g, and cavitation extraction time, 35 min. Under these conditions, the DHQ content in extract was 4.50 ± 0.02 mg/g, and the extraction efficiency was higher than those of traditional techniques. Cavitation can be effectively used to improve the extraction rate by increasing the mass transfer rates and possible rupture of cell wall due to formation of microcavities leading to higher product yields with reduced processing time and solvent consumption. After the extraction process, macroporous resin column chromatography was used to concentrate and purify the DHQ. Three resins were selected from fifteen macroporous resins for further investigation of their performance. Among these resins, AB-8 resin exhibited relatively better adsorption capacities and desorption ratios for DHQ. The ethanol volume fraction of the solutions for sample loading and desorption, and flow rates for loading and desorption were optimized for the macroporous resin column chromatography. [ABSTRACT FROM AUTHOR]