Relevance of n-butanol as a reference gas for odorants and complex odors

Odor analysis by olfactometry relies on the use of n-butanol as a reference compound for standardizing the selection of human panelists. This requires that human sensitivity towards n-butanol is correlated to sensitivity towards other odorants as well as complex odor mixtures. However, there is limited evidence in the literature of such correlations. In this work, datasets from three odor laboratories were investigated in order to clarify this. All panels routinely analyzed n-butanol and H₂S samples. Two of the laboratories analyzed samples from pig production or industry, whereas one laboratory determined odor threshold values for typical pig production odorants. Non-significant correlations were observed in most cases and odor threshold values for structurally related compounds were not well correlated. The work presented strongly indicates that the sensitivity of odor panelists towards n-butanol is not well transferred to other odorants or odor samples. Furthermore, minimization of variance by using n-butanol is not transferable to other odorants or environmental samples. Thus, the harmonization of human panelists for odor analysis based on n-butanol does not appear to result in harmonization with respect to other odorants or odor samples.

Separation and Purification of Fructo-Oligosaccharide by High-Speed Counter-Current Chromatography Coupled with Precolumn Derivatization

High-speed counter-current chromatography (HSCCC) coupled with precolumn derivatization was developed for isolating and purifying fructo-oligosaccharides (FOSs). Firstly, the total FOSs were precolumn derivatized and then separated by high-speed counter-current chromatography (HSCCC) with two-phase solvent system petroleum ether–n-butanol–methanol–water (3:2:1:4, v/v). Secondly, the obtained compounds were deacetylated and the fructo-oligosaccharides (FOSs) with high purity were obtained. Their structures were identified by mass spectrometry (MS) and nuclear magnetic resonance (NMR). This research successfully established a novel strategy for separation and purification of FOS. There is no doubt that the application of the research will be beneficial for the quantitative and qualitative analysis of products containing FOSs.

Catalytic Upgrading of Ethanol to n-Butanol: Progress in Catalyst Development

Because n-butanol as a fuel additive has more advantageous physicochemical properties than those of ethanol, ethanol valorization to n-butanol through homo- or heterogeneous catalysis has received much attention in recent decades in both scientific and industrial fields. Recent progress in catalyst development for upgrading ethanol to n-butanol, which involves homogeneous catalysts, such as iridium and ruthenium complexes, and heterogeneous catalysts, including metal oxides, hydroxyapatite (HAP), and, in particular, supported metal catalysts, is reviewed herein. The structure-activity relationships of catalysts and underlying reaction mechanisms are critically examined, and future research directions on the design and improvement of catalysts are also proposed.

In vitro and ex vivo approach for anti-urolithiatic potential of bioactive fractions of gokhru with simultaneous HPLC analysis of six major metabolites and their exploration in rat plasma

CONTEXT

Tribulus terrestris L. (Zygophyllaceae) fruits have long been used in traditional systems of medicine for the treatment of various urinary diseases including urolithiasis.

OBJECTIVE

To explore the anti-urolithiatic potential of gokhru and to develop an analytical method for quantitative estimation of metabolites for its quality control.

MATERIALS AND METHODS

Aqueous extract of gokhru fruit was prepared through maceration followed by decoction to produce a mother extract, which was further used for polarity-based fractionations. In vitro and ex vivo anti-urolithiatic activity of mother extract and fractions at different concentration (100-1000 μg/mL) were carried out using aggregation assay in synthetic urine and in rat plasma, however, nucleation assay for 30 min was done using confocal microscopy. A simultaneous HPLC method has been developed for quantification of diosgenin, catechin, rutin, gallic acid, tannic acid and quercetin in mother extract and in fractions.

RESULTS

The extraction resulted in 14.5% of w/w mother extract, however, polarity-based fractionation yielded 2.1, 2.6, 1.5, 1.3 and 6.1% w/w of hexane, toluene, dichloromethane (DCM), n-butanol and water fractions, respectively. In vitro and ex vivo studies showed a significant anti-urolithiatic potential of n-butanol fraction. Further, HPLC analysis revealed significantly (p < 0.01) higher content of quercetin (1.95 ± 0.41% w/w), diosgenin (12.75 ± 0.18% w/w) and tannic acid (9.81 ± 0.47% w/w) in n-butanol fraction as compared to others fractions.

DISCUSSION AND CONCLUSION

In vitro and ex vivo studies demonstrated potent anti-urolithiatic activity of n-butanol fraction which can be developed as new phytopharmaceuticals for urolithiasis. HPLC method can be used for quality control and pharmacokinetic studies of gokhru.

Suppression of VEGF-induced angiogenesis and tumor growth by Eugenia jambolana, Musa paradisiaca, and Coccinia indica extracts

CONTEXT

Abnormal angiogenesis and evasion of apoptosis are hallmarks of cancer. Accordingly, anti-angiogenic and pro-apoptotic therapies are effective strategies for cancer treatment. Medicinal plants, namely, Eugenia jambolana Lam. (Myrtaceae), Musa paradisiaca L. (Musaceae), and Coccinia indica Wight & Arn. (Cucurbitaceae), have not been greatly investigated for their anticancer potential.

OBJECTIVE

We investigated the anti-angiogenic and pro-apoptotic efficacy of ethyl acetate (EA) and n-butanol (NB) extracts of E. jambolana (seeds), EA extracts of M. paradisiaca (roots) and C. indica (leaves) with respect to mammary neoplasia.

MATERIALS AND METHODS

Effect of extracts (2-200 μg/mL) on cytotoxicity and MCF-7, MDA-MB-231 and endothelial cell (EC) proliferation and in vitro angiogenesis were evaluated by MTT, 3[H]thymidine uptake and EC tube formation assays, respectively. In vivo tumour proliferation, VEGF secretion and angiogenesis were assessed using the Ehrlich ascites tumour (EAT) model followed by rat corneal micro-pocket and chicken chorioallantoic membrane (CAM) assays. Apoptosis induction was assessed by morphological and cell cycle analysis.

RESULTS

EA extracts of E. jambolana and M. paradisiaca exhibited the highest cytotoxicity (IC50 25 and 60 μg/mL), inhibited cell proliferation (up to 81%), and tube formation (83% and 76%). In vivo treatment reduced body weight (50%); cell number (16.5- and 14.7-fold), secreted VEGF (∼90%), neoangiogenesis in rat cornea (2.5- and 1.5-fold) and CAM (3- and 1.6-fold) besides EAT cells accumulation in sub-G1 phase (20% and 18.38%), respectively.

DISCUSSION AND CONCLUSION

Considering the potent anti-angiogenic and pro-apoptotic properties, lead molecules from EA extracts of E. jambolana and M. paradisiaca can be developed into anticancer drugs.

Antidiabetic, antioxidant and anti inflammatory properties of water and n-butanol soluble extracts from Saharian Anvillea radiata in high-fat-diet fed mice

ETHNOPHARMACOLOGICAL RELEVANCE

According to Saharian traditional medicine, Anvillea radiata Coss. & Dur. (Asteraceae) has been valued for treating a variety of ailments such as gastro-intestinal, liver and pulmonary diseases, and has gained awareness for its beneficial effect on postprandial hyperglycemia. However, to best of our knowledge, no detailed study of the antidiabetic curative effects of this plant has been conducted yet.

AIM OF THE STUDY

To determine the hypoglycemic and antidiabetic effect of dietary supplementation with Anvillea radiata extracts on high-fat-diet (HFD)-induced obesity and insulin resistance in C57BL/6J mice in relation with antioxidant, anti-inflammatory, pancreatic beta-cells and skeletal muscle protection, and digestive enzyme inhibiting properties.

MATERIALS AND METHODS

Six extracts (water soluble and organic) from aerial parts of the plant were analyzed phytochemically (total phenolic and flavonoid content) and screened for in vitro superoxide (by chemiluminescence) and hydroxyl radical (by electron paramagnetic resonance spin-trapping) scavenging, antioxidant (DPPH, TRAP and ORAC assays), xanthine oxidase, metal chelating, α-amylase and α-glucosidase inhibitory property, and protective effects on copper-induced lipoprotein oxidation. Then selected hydroalcoholic and aqueous extracts were assessed for toxicity in normal human lung fibroblasts and A549 cancer cells using FMCA and MTT assays. Two water-soluble extracts having the best overall properties were assessed for their (i) protective effect at 1-15µg/mL on metabolic activity of rat insulinoma-derived INS-1 cells exposed to hyperglycemic medium, and (ii) acute hypoglycemic effect on 16-weeks HFD-induced diabetic mice. Then diabetic mice were administered HFD supplemented by extracts (up to 150mg/kg/day) for 12 additional weeks using standard diet as control and the antidiabetic drug, metformin (150mg/kg), as positive control. Then the antidiabetic, anti-inflammatory and antioxidant activity of extracts were determined.

RESULTS

Of the highly efficient polyphenolics-enriched hydroalcoholic and ethyl acetate extracts, the lyophilized aqueous (AQL) and butanol extracts were not toxic in cells (≤ 400µg/mL) or when given orally in normal mice (≤ 2000mg/kg), exerted a dose-dependent hypoglycemic action in diabetic mice, which was maximal at the dose of 150mg/kg. Upon administering this dose for 12 weeks, both extracts significantly ameliorated body weight control capacity, recovery of plasma glucose and insulin level, reduced oxidative stress in blood, myocardial and skeletal muscles, and improved hyperlipidemic and inflammatory status. Moreover, diabetes-related complications were optimally ameliorated by oral therapy based on halved doses (75mg/kg) of a mixture of AQL and metformin.

CONCLUSIONS

Current investigation supports the traditional medicinal usage of Anvillea radiata and suggests that both readily accessible and low-cost bio-extracts have the potency to develop an antihyperglycemic, antihyperlipidemic and protective agent against beta-cells and muscle dysfunction at doses compatible with the common practices of indigenous people for the management of metabolic disorders.

Intensified Biobutanol Recovery by using Zeolites with Complementary Selectivity

A vapor-phase adsorptive recovery process is proposed as an alternative way to isolate biobutanol from acetone-butanol-ethanol (ABE) fermentation media, offering several advantages compared to liquid phase separation. The effect of water, which is still present in large quantities in the vapor phase, on the adsorption of the organics could be minimized by using hydrophobic zeolites. Shape-selective all-silica zeolites CHA and LTA were prepared and evaluated with single-component isotherms and breakthrough experiments. These zeolites show opposite selectivities; adsorption of ethanol is favorable on all-silica CHA, whereas the LTA topology has a clear preference for butanol. The molecular sieving properties of both zeolites allow easy elimination of acetone from the mixture. The molecular interaction mechanisms are studied by density functional theory (DFT) simulations. The effects of mixture composition, humidity and total pressure of the vapor stream on the selectivity and separation behavior are investigated. Desorption profiles are studied to maximize butanol purity and recovery. The combination of LTA with CHA-type zeolites (Si-CHA or SAPO-34) in sequential adsorption columns with alternating adsorption and desorption steps allows butanol to be recovered in unpreceded purity and yield. A butanol purity of 99.7 mol % could be obtained at nearly complete butanol recovery, demonstrating the effectiveness of this technique for biobutanol separation processes.

Search for compounds contributing to onion-like off-flavor in beer and investigation of the cause of the flavor

Onion-like off-flavor is a highly undesirable property in beer. Although several compounds that impart onion-like odors have been identified, the individual contribution of these compounds to the onion-like off-flavor in beer is not clear. In the present study, we searched for compounds that impart an onion-like odor by gas chromatography (GC)-olfactometry. The analysis of several types of beer revealed that 2-mercapto-3-methyl-1-butanol (2M3MB) and 3-mercapto-3-methyl-1-butanol (3M3MB) were possible causative compounds. Based on the difference threshold values in beer (0.13 ng/mL for 2M3MB and 17.5 ng/mL for 3M3MB) and the quantification values of these compounds in beer samples, only 2M3MB was considered to contribute to the onion-like off-flavor in beer. A further formation factor analysis of 2M3MB revealed that 2M3MB was formed in hopped wort after fermentation, and that the concentration of 2M3MB increased following the hot aeration treatment of wort. These results suggest that preventing the hot aeration of wort is a key factor for reducing 2M3MB levels in beer. In a previous report, 3-methyl-2-buten-1-ol (3MBol) was speculated to be the precursor of 2M3MB and 3M3MB; however, the results of the present quantification analysis and wort addition tests indicate that 3MBol did not contribute to the formation of 2M3MB in the brewing process and that unknown precursors of 2M3MB originated in wort. Identifying the precursor of 2M3MB may facilitate elucidation of the mechanism of 2M3MB formation.

The N-butyl alcohol extract from Hibiscus rosa-sinensis L. flowers enhances healing potential on rat excisional wounds

ETHNO-PHARMACOLOGICAL RELEVANCE

Hibiscus rosa-sinensis L. (HRS), a folk medicine named Zhujin in China, possess anti-tumor, antioxidant, antibacterial, low density lipoprotein oxidation prevention and macrophage death prevention effects. The leaves and red flowers of HRS have been traditionally used to treat with furuncle and ulceration.

AIM OF THE STUDY

To investigate the efficacy and possible mechanism of the N-butyl alcohol extract of HRS (NHRS) red flowers in wound healing by analyzing the collagen fiber deposition, angiogenic activity and macrophages action of the NHRS.

MATERIALS AND METHODS

In an excisional wound healing model in rats, different concentrations of NHRS, or recombinant bovine basic fibroblast growth factor (rbFGF), were respectively applied twice daily for 9 days. Histopathology was assessed on day 9 via hematoxylin and eosin (HE) and Masson's trichrome (MT) staining, and immunohistochemistry for vascular endothelial growth factor (VEGF), transforming growth factor-β1 (TGF-β1) and CD68. Immunomodulation by NHRS was evaluated by a carbon clearance test in mice.

RESULTS

Wound healing post-surgery was greater in the rbFGF-control, NHRS-M and MHRS-H groups than in the model and 5% dimethylsulfoxide (DMSO)-control groups after the third day. By the sixth day the wound contraction of NHRS-M and MHRS-H groups was much higher than the rbFGF-control group. HE and MT staining revealed that epithelialization, fibroblast distribution, collagen deposition of NHRS-M- and NHRS-H-control groups were significantly higher than the model group. Moreover, immunohistochemistry showed more intense staining of VEGF, TGF-β1 and CD68 in the rbFGF- and NHRS-control groups, compared to that in model and 5% DMSO-control groups. The clearance and phagocytic indices of NHRS-M- and NHRS-H-control groups were significantly higher than that of the carboxyl methyl cellulose (CMC) group in mice.

CONCLUSION

NHRS accelerates wound repair via enhancing the macrophages activity, accelerating angiogenesis and collagen fiber deposition response mediated by VEGF and TGF-β1.

Antimicrobial activity of pomegranate peel extracts as affected by cultivar

BACKGROUND

Some studies have reported that different parts of the pomegranate fruit, especially the peel, may act as potential antimicrobial agents and thus might be proposed as a safe natural alternative to synthetic antimicrobial agents. The high tannin content, especially punicalagin, found in pomegranate extracts, has been reported as the main compound responsible for such antimicrobial activity. Because the pomegranate peel chemical composition may vary with the type of cultivar (sweet, sour-sweet and sour), pomegranates may also differ with respect to their antimicrobial capacity.

RESULTS

The extract from PTO8 pomegranate cultivar peel had the highest antimicrobial activity, as well as the highest punicalagins (α and β) and ellagic acid concentrations. In the results obtained from both antibacterial and antifungal activity studies, the sour-sweet pomegranate cultivar PTO8 showed the best antimicrobial activity, and the highest ellagic acid concentrations.

CONCLUSION

The results of the present study suggest that ellagic acid content has a significant influence on the antimicrobial activity of the pomegranate extracts investigated. The pomegranate peel of the PTO8 cultivar is a good source of antifungal and antibacterial compounds, and may represent an alternative to antimicrobial agents of synthetic origin. © 2016 Society of Chemical Industry.

New Iridoid Glucosides from Caryopteris incana (Thunb.) Miq. and Their α-Glucosidase Inhibitory Activities

In our continued investigations of the plant Caryopteris incana, five new iridoid glucosides 1-5, including two cis-trans-isomers, 3 and 4, along with six known compounds 6-11, were isolated from the n-butyl alcohol (n-BuOH) soluble fraction of whole dried material of Caryopteris incana. Their structures were established by a combination of spectroscopic techniques, including 1D and 2D NMR and high resolution electrospray ionization mass spectroscopy (HR-ESI-MS). Furthermore, all isolates were evaluated for their yeast α-glucosidase inhibitory effects. Among these compounds, 4-8 and 10 exhibited potent inhibition of α-glucosidase.

Rapid Screening and Identification of BSA Bound Ligands from Radix astragali Using BSA Immobilized Magnetic Nanoparticles Coupled with HPLC-MS

Radix astragali is widely used either as a single herb or as a collection of herbs in a complex prescription in China. In this study, bovine serum albumin functionalized magnetic nanoparticles (BSA-MN) coupled with high performance liquid chromatography-mass spectrometry (HPLC-MS) were used to screen and identify bound ligands from the n-butanol part of a Radix astragali extract. The prepared BSA-MN showed sufficient magnetic response for the separation with an ordinary magnet and satisfied reusability. Fundamental parameters affecting the preparation of BSA-MN and the screening efficiency were studied and optimized. Under the optimum conditions, four bound ligands were screened out from the n-butanol part of a Radix astragali extract and identified as genistin (1), calycosin-7-O-β-d-glucoside (2), ononin (3) and formononetin (4). This effective method could be widely applied for rapid screening and identification of active compounds from complex mixtures without the need for preparative isolation.

Stachytarpheta cayennensis extract inhibits promastigote and amastigote growth in Leishmania amazonensis via parasite arginase inhibition

ETHNOPHARMACOLOGY RELEVANCE

Stachytarpheta cayennensis is a plant that is traditionally used to treat tegumentary leishmaniasis and as an anti-inflammatory agent.

AIM OF THE STUDY

This study aimed to evaluate the action of S. cayennensis extracts on the Leishmania (Leishmania) amazonensis arginase enzyme.

MATERIALS AND METHODS

S. cayennensis was collected from the Brazilian Amazon region. Aqueous extracts were fractionated with n-butanol. The leishmanicidal effects of the n-butanolic fraction (BUF) were evaluated in L. (L.) amazonensis promastigotes and amastigotes. BUF was tested against recombinant arginase from both L. (L.) amazonensis and macrophage arginase. Promastigote cultures and infected macrophage cultures were supplemented with L-ornithine to verify arginase inhibition. NMR analysis was used to identify the major components of BUF.

RESULTS

BUF showed an EC₅₀ of 51 and 32µg/mL against promastigotes and amastigotes of L. (L.) amazonensis, respectively. BUF contains a mixture of verbascoside and isoverbascoside (7:3 ratio) and is a potent L. (L.) amazonensis arginase inhibitor (IC₅₀=1.2µg/mL), while macrophage arginase was weakly inhibited (IC₅₀>1000µg/mL). The inhibition of arginase by BUF in promastigotes and amastigotes could be demonstrated by culture media supplementation with L-ornithine, a product of the hydrolysis of L-arginine by arginase.

CONCLUSIONS

Leishmanicidal effects of the S. cayennensis BUF fraction on L. (L.) amazonensis are associated with selective parasite arginase inhibition.

Downstream extraction process development for recovery of organic acids from a fermentation broth

The present study focused on organic acids (OAs) recovery from an acidogenic fermentation broth, which is the main problem regarding the use of OAs for production of ester-based new generation biofuels or other applications. Specifically, 10 solvents were evaluated for OAs recovery from aqueous media and fermentation broths. The effects of pH, solvent/OAs solution ratios and application of successive extractions were studied. The 1:1 solvent/OAs ratio showed the best recovery rates in most cases. Butyric and isobutyric acids showed the highest recovery rates (80-90%), while lactic, succinic, and acetic acids were poorly recovered (up to 45%). The OAs recovery was significantly improved by successive 10-min extractions. Alcohols presented the best extraction performance. The process using repeated extractions with 3-methyl-1-butanol led to the highest OAs recovery. However, 1-butanol can be considered as the most cost-effective option taking into account its price and availability.

Effect of chemical pretreatments on corn stalk bagasse as immobilizing carrier of Clostridium acetobutylicum in the performance of a fermentation-pervaporation coupled system

In this study, different pretreatment methods were evaluated for modified the corn stalk bagasse and further used the pretreated bagasse as immobilized carrier in acetone-butanol-ethanol fermentation process. Structural changes of the bagasses pretreated by different methods were analyzed by Fourier transform infrared, crystallinity index and scanning pictures by electron microscope. And the performances of batch fermentation using the corn stalk based carriers were evaluated. Results indicated that the highest ABE concentration of 23.86g/L was achieved using NaOH pretreated carrier in batch fermentation. Immobilized fermentation-pervaporation integration process was further carried out. The integration process showed long-term stability with 225-394g/L of ABE solvents on the permeate side of pervaporation membrane. This novel integration process was found to be an efficient method for biobutanol production.

Butanol production in acetone-butanol-ethanol fermentation with in situ product recovery by adsorption

Activated carbon Norit ROW 0.8, zeolite CBV901, and polymeric resins Dowex Optipore L-493 and SD-2 with high specific loadings and partition coefficients were studied for n-butanol adsorption. Adsorption isotherms were found to follow Langmuir model, which can be used to estimate the amount of butanol adsorbed in acetone-butanol-ethanol (ABE) fermentation. In serum-bottle fermentation with in situ adsorption, activated carbon showed the best performance with 21.9g/L of butanol production. When operated in a fermentor, free- and immobilized-cell fermentations with adsorption produced 31.6g/L and 54.6g/L butanol with productivities of 0.30g/L·h and 0.45g/L·h, respectively. Thermal desorption produced a condensate containing ∼167g/L butanol, which resulted in a highly concentrated butanol solution of ∼640g/L after spontaneous phase separation. This in situ product recovery process with activated carbon is energy efficient and can be easily integrated with ABE fermentation for n-butanol production.

Effect of Viscum schimperi on advanced glycation endproducts formation

Diabetes is a disease characterized by elevated uncontrolled glucose level. Hyperglycemia results in diabetic complication due to a reaction between sugar and amino acid of proteins to form advanced glycation endproducts (AGEs) in different tissues. Medicinal plants are considered as a great source of bioactive compounds that affect many ailments. In this regard; AGEs formation could be inhibited by many bioactive compounds isolated from medicinal plants. Viscum schimperi Engl. is a plant belongs to Loranthaceae and known for its antidiabetic activity. In this study; total methanol extract of V. schimperi (VT) was prepared, suspended in water and subjected to fractionation with chloroform followed by n-butanol to give (VC) and (VB) fractions respectively. The aqueous mother liquor was evaporated to form (VA) fraction. The inhibitory effect of all prepared fraction on the formation of advanced glycation endproducts (AGEs) was studied. The results revealed that V. schimperi extract and its different fractions inhibited protein glycation and oxidation of BSA induced by ribose together with decrease of protein aggregation. In conclusion; V. schimperi will be useful in management of diabetic complications based on its inhibition of advanced glycation endproduct formation.

Protective effects of Semiaquilegia adoxoides n-butanol extract against hydrogen peroxide-induced oxidative stress in human lens epithelial cells

Context Hydrogen peroxide (H2O2)-induced damage in the lens epithelium leads to cell death and cataract. Semiaquilegia adoxoides (DC.) Makino (Ranunculaceae), a folk medicine of Hmong (an ethnic group of China), has been traditionally used to treat cataract; however, the underlying molecular mechanism is yet to be uncovered. Objective This study aimed to investigate whether the n-butanol extract of S. adoxoides (nSA) is effective against the H2O2-induced oxidative stress in human lens epithelial (HLE) cells. Materials and methods Human lens epithelial (SRA 01/04) cells were stimulated by H2O2 (250 μM) in the presence or absence of nSA. The antioxidant effects of nSA were determined in terms of cell viability (MTT assay), apoptosis (AnnexinV/PI staining), radical scavenging capability (various enzymatic assays), loss of mitochondrial membrane potential (Rhodamine 123 staining), expression of apoptotic markers including caspase-3 and caspase-9 and the change of Bcl-2/Bax ratio (western blot) in the HLE cells. Results The results showed that pretreatment of nSA (250, 500 and 1000 μg/mL) markedly reduced H2O2-induced cellular apoptosis and malondialdehyde accumulation, but elevated the activities of total superoxide dismutase, catalase, glutathione peroxidase. Thus, the total antioxidative capability was enhanced upon the nSA treatment meanwhile the loss of mitochondrial membrane potential was prevented. Moreover, nSA at concentrations of 250, 500 and 1000 μg/mL also significantly suppressed the activation of caspase-3 and -9, and increased the Bcl-2/Bax ratio in the HLE cells. Discussion and conclusion Our findings suggested that nSA is a potential prophylactic agent in the prevention of cataractogeneis.

Sustainable hydrogen production from bio-oil model compounds (meta-xylene) and mixtures (1-butanol, meta-xylene and furfural)

In the present work m-xylene and an equimolecular mixture of m-xylene, 1-butanol and furfural, all of them bio-oil model compounds, were studied in steam reforming (SR) conditions. Three different nickel catalysts, which showed to be active in 1-butanol SR (Ni/Al2O3, Ni/CeO2-Al2O3 and Ni/La2O3-Al2O3), were tested and compared with thermodynamic equilibrium values. Tests were carried out at temperatures from 800 to 600°C at atmospheric pressure with a steam to carbon ratio (S/C) of 5.0. Despite the different bio-oils fed, the amount of moles going through the catalytic bed was kept constant in order to obtain comparable results. After their use, catalysts were characterized by different techniques and those values were correlated with the activity results. All catalysts were deactivated during the SR of the mixture, mainly by coking. The highest hydrogen yields were obtained with Ni/Al2O3 and Ni/CeO2-Al2O3 catalysts in the SR of m-xylene and SR of the mixture, respectively.

Protective effect of n-butyl alcohol extracts from Rhizoma Pinelliae Pedatisectae against cerebral ischemia-reperfusion injury in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Rhizoma Pinelliae Pedatisectae (RPP) has been commonly used in traditional Chinese medicine (TCM) for treatment of various neurological related diseases. However, the mechanisms have not been fully clarified yet. The present study was designed to investigate the therapeutic effect of RPP against cerebral ischemic/reperfusion (I/R) injury in rats models, and more importantly, to explore the underlying mechanism.

MATERIALS AND METHODS

Cerebral ischemia and reperfusion was established through the classic middle cerebral artery occlusion (MCAO) for 2h, followed by 24h reperfusion. Rats were orally given different doses of n-butyl alcohol extracts (NBES) of RPP or saline for one week before induction of ischemia. Neurological defect scoring, cerebral infarct volume, oxidative stress markers, inflammatory reaction and nerve cell apoptosis were then estimated.

RESULTS

It showed that NBES could alleviate in a dose-dependent manner neurological deficit and reduce the infarct volume in vivo. The protective effects of NBES were associated with increased Superoxide dismutase (SOD) activity and decreased malonaldehyde (MDA), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels. In addition, ischemia-induced neuron apoptosis was inhibited by NBES pretreatment, and western blot showed NBES upregulated expressions of B-cell leukemia-2 (Bcl-2) and downregulated Bcl-2-associated X (Bax) expression.

CONCLUSION

NBES prevent cerebral I/R injury by alleviating neuronal oxidative injury, inflammatory reaction and neuron apoptosis. The research for the traditional use of RPP provided certain theoretical basis.

Flavonol glycosides and other phenolic compounds from Viola tianshanica and their anti-complement activities

CONTEXT

Viola tianshanica Maxim. (Violaceae) is a perennial herb distributed in Central Asia, especially in the Xinjiang Uygur Autonomous Region (XUAR) of China. Preliminary study showed that the ethanol extract of the herb exhibited the anti-complement activity against the classical pathway, but the active components responsible for this capacity remain unknown and are yet to be studied.

OBJECTIVE

The objective of this study was the isolation and identification of the anti-complement constituents of V. tianshanica.

MATERIALS AND METHODS

The ethyl acetate and n-butanol fractions from the ethanol extract of V. tianshanica were purified. The structures of the isolates were identified by spectroscopic methods, and comparing their spectral data with those reported in the literature. All the isolates (0.02-2.50 mg/mL) were evaluated for their anti-complement activity against the classical and alternative pathways.

RESULTS

Twenty-one phenolic compounds including 15 flavonol O-glycosides (1-15), one flavone 6,8-di-C-glycoside (16), one flavone aglycone (17), and four phenolic acid derivatives (18-21) were isolated and identified. Bioassay showed that 11 compounds inhibited the classical pathway and the alternative pathway with CH50 and AP50 values of 0.113-1.210 mM and 0.120-1.579 mM, respectively. Preliminary mechanistic study using complement-depleted sera demonstrated that 1 acted on C1q, C2, C4, and C9 components, 16 on C1q, C4, and C5, and 21 on C1q, C3, C4, and C9.

CONCLUSION

All isolated compounds except 1 and 10 were reported for the first time from V. tianshanica. Compound 16 is the first flavone C-glycoside isolated from the herb. Flavonol O-glycosides and phenolic acids contributed the anti-complement activity of the herb.

Synergistic Effect of Compounds from a Chinese Herb: Compatibility and Dose Optimization of Compounds from N-Butanol Extract of Ipomoea stolonifera

The herbal medicine Ipomoea stolonifera (I. stolonifera) has previously been shown to have considerable anti-inflammatory potential in vivo and in vitro. To establish a method for exploring the synergistic effects of multiple compounds, we study the compatibility and dose optimization of compounds isolated from n-butanol extract of I. stolonifera (BE-IS). Raw264.7 cell was treated with lipopolysaccharide (LPS) in the presence of compounds from BE-IS, namely scopoletin, umbelliferone, esculetin, hesperetin and curcumin, using the orthogonal design, uniform design and median-effect method. To verify the best efficacy of principal constituents in vivo, the uniform design was used in the croton oil-induced mouse ear edema model. The results from LPS-induced the production of prostaglandin E2 (PGE2) show that, esculetin, curcumin and hesperetin were the principal constituents that had synergistic effects when used at the optimal ratio. Additionally, the principal constituents were found to work synergistically in the croton oil-induced mouse ear edema model at low doses. It turned out that the three experimental optimization and analysis methods (orthogonal design, uniform design and median-effect method) can be effectively used to solve both compatibility and dose optimization for combined use of multiple compounds.

Comparison of Antioxidant Capability after Isopropanol Salting-Out Pretreatment and n-Butanol Partition Extraction, and Identification and Evaluation of Antioxidants of Sedum formosanum N.E.Br

Crude extracts of Sedum formosanum N.E.Br. obtained from n-butanol partition (BP) and isopropanol salting-out pretreatment (ISP) were analyzed using antioxidation assays. The results indicated that the extract from ISP contained more potent antioxidants and thus exhibited more antioxidant activity in all the assays. The superoxide radical-scavenging activity and inhibition of nitric oxide radicals achieved after ISP were 3.65 and 2.18 times higher than those achieved through BP, respectively. Eight bioactive natural products were isolated and identified according to an analysis of antioxidation activity in different fractions of the ISP crude extract, namely three cyanophoric glycosides 1-3, three flavonoids 4-6 and two phenolic compounds (7 and a new compound 8). Among them, compounds 5 and 6 exhibit the highest antioxidation capability, and the ISP is suitable for obtaining compounds 5 and 6 using HPLC chromatograms. Therefore, ISP is an excellent extraction technology that can be used to extract antioxidant compounds in the nutraceutical and pharmaceutical industries.

Improvement of the liver pathology by the aqueous extract and the n-butanol fraction of Sida pilosa Retz in Schistosoma mansoni-infected mice

ETHNOPHARMACOLOGICAL RELEVANCE

Sida pilosa Retz (Malvaceae) is a plant used in Africa for the treatment of intestinal helminthiasis, lower abdominal pains and dysmenorrhea.

AIM OF THE STUDY

In order to determine the potential use of S. pilosa in the treatment of schistosomiasis mansoni, we evaluated the schistosomicidal, antioxidant and anti-fibrotic properties of the aqueous extract and the n-butanol fraction of its aerial parts.

MATERIAL AND METHODS

S. pilosa aqueous extract (SpAE) at 100, 200 and 400mg/kg and n-butanol fraction (SpBF) at 50, 100 and 200mg/kg were administered per os to Schistosoma mansoni-infected mice for 4 weeks. Praziquantel (100mg/kg × 5 days) was used as reference drug. After sacrifice, worm burden and egg count, transaminases and proteins levels were evaluated. Malondialdehyde (MDA), lipid hydroperoxydes (LOOH), catalase (CAT), superoxide dismutase (SOD), eosinophil peroxidase (EPO) and myeloperoxidase (MPO) were also measured. The anti-fibrotic effect of the plant was evaluated by the determination of hydroxyproline and γ-interferon (IFN-γ).

RESULTS

The treatment of S. mansoni-infected mice by SpAE or SpBF resulted in a moderate reduction of worm burden and egg load in the liver and intestine. Both SpAE and SpBF significantly reversed the increasing liver proteins, MDA, LOOH and CAT levels induced by the infection. Moreover, SOD activity was improved by SpAE and SpBF. Schistosomiasis mansoni considerably increased the EPO (p<0.001) and MPO activities (p<0.001). SpAE treatment significantly reduced EPO and MPO activities at all doses. SpBF failed to reduce the increasing MPO and decreased EPO only at the highest dose. S. mansoni-infection induced an increase in hydroxyproline content (p<0.001) and a decrease in IFN-γ level (p<0.001). Both SpAE and SpBF significantly reduced hepatic hydroxyproline content, while only SpAE (p<0.05) improved IFN-γ level.

CONCLUSION

These results suggest that the liver pathology in schistosomiasis mansoni is improved by S. pilosa aqueous extract, which disclosed a moderate schistosomicidal, but strong antioxidant and anti-fibrotic activities. The n-butanol fraction was however less active than the aqueous extract.

Antimicrobial potentials of different solvent extracted samples from Physalis ixocarpa

The present study investigates the antimicrobial activities of different solvent extracted samples isolated from different parts of Physalis ixocarpa through disc diffusion assay using three different concentrations. Statistical analysis of the data revealed that different parts of the plant showed varying degree of inhibition against different bacteria at different concentrations. Different solvent extracted samples from the calyx showed inhibitory activity against most of the bacteria under study. Extracts from leaf and fruit samples showed activity against S. aureus and K. pneumoniae and extracts from the stem tissues were effective to control the growth of E. coli and K. pneumoniae. Crude methanolic extract from the stem and n-butanol extracted samples from fruit exhibited strong inhibitory activity against Klebsiella pneumoniae at highest concentrations. Antifungal activity was observed only in crude methanol extract from the leaf against Rhizopus stolinifer, Aspergillus niger and Penicillium chrysogenum.