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Background and aim The liver is the primary organ affected by cholestasis, and complications such as renal injury, renal failure, and the need for renal transplantation are associated with cholestatic liver disease. There is substantial evidence indicating that reactive oxygen species (ROS) and mitochondrial impairment are fundamental mechanisms underlying cholestasis-induced hepatic and renal injury. Edaravone (EDV) is a potent radical scavenger and antioxidant that may prevent oxidative stress and improve impaired mitochondrial function in various diseases. This study was performed to evaluate the effects and mechanisms of action of EDV on hepatic and renal injury in an animal model of cholestasis. Methods Rats subjected to bile duct ligation (BDL) were treated with EDV 1 or 10 mg/kg/day intraperitoneally for 14 consecutive days. Biomarkers of oxidative stress and mitochondrial impairment in the liver and kidney were assessed in EDV-treated and untreated rats with cholestasis. Results Significant increases in tissue ROS level, lipid peroxidation, protein carbonylation, and oxidized glutathione level were detected in rats subjected to BDL. Additionally, significant decreases in tissue glutathione level and antioxidant capacity were observed in the hepatic and renal tissues of rats with cholestasis. Markers of mitochondrial impairment, including mitochondrial depolarization, lipid peroxidation, mitochondrial permeabilization, depleted adenosine triphosphate content, and decreased dehydrogenase activity, were also detected in rats subjected to BDL. Furthermore, portal inflammation, necrosis, and tissue fibrosis were detected in the liver and significant tubular atrophy and interstitial inflammation, as well as fibrotic lesions, were detected in the kidneys of rats with cholestasis. EDV treatment significantly mitigated cholestasis-associated hepatic and renal injury. Conclusions The antioxidative properties of EDV and its positive effects on the indices of mitochondrial function may be critical factors contributing to protection against cholestasis-associated hepatic and renal injury.

Introduction: The cholestatic liver disease primarily affects hepatic tissue. Cholestasis could also influence the function of other organs rather than the liver. Cholestasis-induced renal injury is a severe clinical complication known as "cholemic nephropathy" (CN). Bile duct ligation (BDL) is a reliable experimental tool for inducing CN. Although the precise mechanism of renal injury in cholestasis is not fully recognized, several studies mentioned the role of oxidative stress in this complication. There is no promising pharmacological intervention against CN. Carnosine (CAR) is a dipeptide widely investigated for its pharmacological effects. Radical scavenging and antioxidative stress are major features of CAR. The current study was designed to evaluate the role of CAR supplementation on the CN. Methods: CAR (250 and 500 mg/kg, i.p) was administered to BDL rats for 14 consecutive days. Serum and urine markers of renal injury, biomarkers of oxidative stress in the kidney tissue, and renal histopathological alterations were monitored. Results: Significant elevation in oxidative stress biomarkers, including ROS formation, oxidized glutathione (GSSG) levels, lipid peroxidation, and protein carbonylation were found in the kidney of BDL rats. Moreover, renal tissue antioxidant capacity and reduced glutathione (GSH) levels were significantly decreased in the renal tissue of cholestatic animals. Renal histopathological alterations, including tubular atrophy, interstitial inflammation, tissue fibrosis, and cast formation, were detected in the kidney of BDL rats. It was found that CAR administration significantly protected the renal tissue of cholestatic animals. Conclusion: The antioxidative properties of this peptide might play a fundamental role in its protective properties during cholestasis.

Catalytic co-conversion of Kraft lignin (KL) and linear low-density polyethylene (LLDPE) over mesostructured catalysts was examined using a micro-pyrolyzer equipped with gas chromatography-mass spectrometry/flame ionization detector (MPy-GC/MS/FID). Mesoporous catalysts of Al-SBA-15 and mesoZSM-5 were synthesized and characterized by N2 sorption, ammonia temperature programmed desorption, and X-ray diffraction. The characterization results indicated that mesoZSM-5 had the smaller average pore size (4.10 nm) than Al-SBA-15 (10.70 nm), but its total acidity (both weak and strong acid sites) was much higher than Al-SBA-15. When they were applied as catalysts in the pyrolysis of KL and LLDPE, the mesoZSM-5 exhibited higher catalytic activity for aromatic hydrocarbon production due to its higher acidity and MFI pore structure. Indeed, synergistic synthesis of aromatic hydrocarbons was achieved via the catalytic co-pyrolysis of KL and LLDPE because of the H-donating effect of LLDPE; the experimental yields (GC/MS area; abundance vs. time) of aromatic hydrocarbons in the oils obtained from catalytic co-pyrolysis of KL/LLDPE (1:1) over Al-SBA-15 (8.76 × 107) and mesoZSM-5 (27.58 × 107) were ∼1.5 fold higher than the theoretical yields.

Cholestasis-associated renal injury, known as cholemic nephropathy (CN), is a severe clinical complication. CN could lead to acute kidney injury. However, there is no specific pharmacological intervention for cholestasis-induced renal injury. Oxidative stress and mitochondrial impairment seem to play a role in the pathogenesis of CN. Betaine (3-methyl glycine; BET) is an amino acid derivative with a wide range of pharmacological actions. Several studies mentioned the effects of BET on oxidative stress in different experimental models. It has also been found that BET positively affected mitochondrial function. The current study aimed to evaluate the effects of BET supplementation on CN in the bile duct ligation (BDL) model of cholestasis. BET (0.25% and 1% w: v in drinking water) was administered to BDL animals for seven consecutive days. Biomarkers of oxidative stress and mitochondrial indices were evaluated in cholestatic animals. Significant elevation in reactive oxygen species formation, lipid peroxidation, and oxidized glutathione (GSSG) was evident in BDL rats. Moreover, reduced glutathione (GSH) levels and renal antioxidant capacity were decreased in cholestatic animals. Mitochondrial depolarization, mitochondrial permeabilization, decreased mitochondrial dehydrogenases activity, and lipid peroxidation was also detected in the kidney of BDL rats. Tubular atrophy, interstitial inflammation, and renal fibrosis were also detected in BDL rats. BET alleviated biomarkers of oxidative stress, improved mitochondrial indices, and decreased renal histopathological alterations in BDL animals. The antioxidant effects and the positive effects of BET on cellular mitochondria seem to play a fundamental role in its nephroprotective role during cholestasis.

Ultraviolet (UV) radiation is a common environmental factor that affects the growth and productivity of plants. However, many plants have evolved structural, physiological, and biochemical mechanisms to cope with UV radiation. Viola odorata, is exposed to extended daily sunlight and acclimatization mechanisms have been developed in response to natural UV radiations. The purpose of this study was to assess the changes in the morphology and abundance of mucilaginous structures besides the physiological and biochemical changes of V. odorata plants under exposure to UV-B radiation (2 h and 4 h daily). After 4 weeks of treatments, the obtained results showed that the V. odorata plants responded to UV-B radiation anatomically and physiologically through changes in thickening of the cuticle, production of mucilage and enzymatic and non-enzymatic antioxidants; also, the content of malondialdehyde (MDA) and hydrogen peroxide (H2O2) was increased. The investigation showed that the duration of exposure to UV-B radiation had a negative correlation with the content of carotenoids, chlorophyll a, chlorophyll b, and soluble carbohydrates, whereas it had a positive correlation with the content of mucilage, anthocyanins, flavonoids, MDA, H2O2, and activity of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POX) enzymes. These findings display the different defense mechanisms in V. odorata plants against UV-B radiation.

Excessive fatty acids and glucose uptake support the infiltration of adipose tissue (AT) by a variety of immune cells including neutrophils, pro-inflammatory M1 macrophages, and mast cells (MCs). These cells promote inflammation by releasing pro-inflammatory mediators. The involvement of MCs in AT biology is supported by their accumulation in the AT of obese individuals along with significantly higher serum levels of MC-derived tryptase. AT-resident MCs under the influence of locally derived adipokines such as leptin become activated and release pro-inflammatory cytokines including TNFα that worsens the inflammatory state. MCs support angiogenesis in AT by releasing chymase and inducing preadipocyte differentiation and also the proliferation of adipocytes through 15-deoxy-delta PGJ2/PPARγ interaction. Additionally, they contribute to the remodeling of the AT extracellular matrix (ECM) and play a role in the recruitment and activation of leukocytes. MC degranulation has been linked to brown adipocyte activation, and evidence indicates an important link between MCs and the appearance of BRITE/beige adipocytes in white AT. Cell crosstalk between MCs and AT-resident cells, mainly adipocytes and immune cells, shows that these cells play a critical role in the regulation of AT homeostasis and inflammation.

Pyrolysis oil (bio-oil) consists of high water content and vast variety of oxygenates (acids, alcohols, aldehydes, esters, ketones, sugars and phenols), causing some undesirable properties that prevent the direct use of bio-oil as a transportation fuel. Bio-oil upgrading to decrease its oxygen content provides a sustainable fuel that can be considered a valuable substitution for depleting fossil fuels. Catalytic hydrodeoxygenation (HDO) is an efficient method for bio-oil upgrading. This paper presents the HDO of crude bio-oil in supercritical fluid (ethanol, methanol, and 2-propanol) using a batch high pressure reactor. Supercritical fluids have unique physicochemical properties of liquid-like density and gas-like high diffusivity and low viscosity. The upgrading efficiency was evaluated by measuring the elemental composition (CHNS O), water content, carbon residue, and high heating value (HHV) of the bio-oil upgraded over Ni/HBeta catalyst. Compared to ethanol and 2-propanol, supercritical methanol resulted in a higher decrease in the oxygen content of bio-oil. The activity of Ni/HBeta was examined by varying the Ni loading (5–20 wt%), initial hydrogen pressure (10–30 bar), and reaction time (2–6 h). Meanwhile, effects of support materials (HZSM-5, HBeta, HY, Al-SBA-15, and silylated HBeta) on the performance of nickel catalyst in bio-oil upgrading were investigated using supercritical methanol.

Due to global concerns about the emissions, limited hydrocarbon fuel resources and high fuel prices, a lot of researches have been done to improve the process of combustion in the internal combustion engines. Natural gas (NG) is one of the best available fuels because of its price and accessibility. On the other hand, the studies show dual-fuel combustion engines improve the reactivity of the fuel–air mixture and also increase the ignition delay (ID). In this study, NG/diesel dual-fuel engine has been simulated using AVL FIRE coupled with the kinetic mechanism and the effect of temperature and pressure at inlet valve closing (IVC) has been investigated. The results showed that with increasing the pressure and temperature at IVC, the maximum in-cylinder pressure increases, while the ID decreases. With higher pressure and temperature, the carbon monoxide (CO) level decreases. Moreover, higher pressure decreases the start of combustion temperature and carbon dioxide (CO2) while with a higher temperature at IVC both of them will be increased. It was also observed that with a higher temperature at IVC, the ringing intensity (RI) increases while with higher pressure, the RI reduces. Besides, increasing both temperature and pressure at IVC raises the thermal efficiency.

In this paper, the effects of inlet valve closing temperature (TIVC) and exhaust gas recirculation (EGR) on the emissions and the performance of a reactivity controlled compression ignition (RCCI) engine have been numerically investigated. The numerical results were obtained for TIVC variations from 293 to 353 K and the EGR variations from 0 to 25%. For this purpose, the natural gas was injected in inlet port as a low reactivity fuel, while the diesel fuel was directly injected in the cylinder as a high reactivity fuel. For the numerical simulation validation, the results were compared to the reference data. The comparison shows that the in-cylinder pressure, rate of heat release (RoHR), soot and nitrogen oxide (NOx) emissions results are in good agreement with the reference data. According to the results, with increasing the EGR, the maximum in-cylinder pressure and also the maximum RoHR will be decreased. Moreover, increasing the EGR can considerably reduce NOx and soot emissions. When EGR increases from 0 to 25%, the NOx emission decreases from 0.47 to 0.02 g kW−1 h−1, while soot decreases from 0.009 to 0.0005 g kW−1 h−1. Also, increasing the TIVC will significantly increase the maximum pressure, RoHR and NOx and soot emissions. When TIVC increases from 293 to 353 k, the NOx emission increases from 0.01 to 0.41 g kW−1 h−1 and also soot from 0.0005 to 0.011 g kW−1 h−1. Finally, the results show that both of the TIVC and the EGR play important roles in controlling the combustion phase of an RCCI engine.

Bio-oil (biomass pyrolysis oil) has some undesirable properties (e.g., low heating value, high corrosiveness, and high viscosity) that restrain its direct use as a transportation fuel. The emulsification of bio-oil and diesel is an effective and convenient method to use bio-oil in the present transportation fuel infrastructure. The addition of an emulsifying agent (emulsifier or surfactant) to two immiscible liquids of diesel and bio-oil is an important step in emulsification. The hydrophilic–lipophilic balance (HLB) value, according to the chemical structure and characteristics of the emulsifier, is a key parameter for selecting a surfactant. In this study, an ether treatment of raw bio-oil was carried out to separate the ether-soluble fraction of bio-oil from its heavy (dark brown and highly viscous) fraction, and the ether-extracted bio-oil (EEO) was processed further for emulsification into diesel fuel. The effects of the HLB value of the emulsifier and the contents of EEO, diesel, and emulsifier on the stability of the EEO/diesel emulsion were investigated. To optimize the HLB value of the emulsifier, different HLB values (4.3–8.8), which were prepared by mixing different amounts of Span 80 and Tween 60 as surfactants, were used for the EEO and diesel emulsification. A HLB value of 7.3 with diesel, EEO, and emulsifier contents of 90, 5, 5 wt%, and 86, 7.4, 6.6 wt% resulted in EEO/diesel emulsions (without phase separation) stable for 40 and 35 days, respectively. Measurement of the high heating value (HHV) of the emulsified fuels gave a 44.32 and 43.68 MJ/kg values for the EEO to emulsifier mass ratios of 5:5 and 7.4:6.6, respectively. The stability of emulsified EEO and diesel was verified by TGA and FT-IR methods.

In the present study, two novel chalcone glycosides, trans-3-ethoxy-4-O-(glucopyranoside) -2', 3', 4', 5', 6' -pentahydroxy chalcone (compound 1) and trans-3-methoxy-4-O-(glucopyranoside) -2', 3', 4', 5', 6' -pentahydroxy chalcone (compound 2) have been isolated from the leaves of Viburnum lantana L. The structures were elucidated by using 1H-NMR, 13C-NMR, 2D-NMR such as HMQC, HMBC and NOE experiments and UV-Vis, MS and IR spectra. The antioxidant property of hydroalcoholic extract was evaluated by DPPH style. The results revealed that the leave extract possesses significant antioxidant activity (IC50 = 52 µg/mL). This study indicates that hydroalcoholic extract of the leaves from this species is an important source of chalcone and flavonoid derivatives, as well as of useful natural antioxidants. These chalcone glycoside compounds were isolated for the first time from V. lantana leaves.

Both subsets of MCs including MCTC (tryptase-positive, chymase-positive) and MCT (tryptase-positive, chymase-negative) are present in the testis and epididymis. Increased number of MCs, higher levels of MC-released tryptase in testis and seminal plasma of males with fertility problems, and promoting sperm motility in individuals with oligozoospermia after using MC blockers provide evidence that MCs may play a role in male infertility/subfertility disturbances. MC-released tryptase and histamine contribute to the fibrosis and may disrupt spermatogenesis. MCs not only influence the process of spermatogenesis but also have effects on the function of other testis-residing cells. MC-derived histamine may influence the steroidogenesis of Leydig cells by acting through H1R and H2R receptors. Additionally, the interaction between MC-released ATP and P2X receptors expressed on the peritubular cells may induce the production of the pro-inflammatory mediators by peritubular cells. Further investigations showed that MCs may be involved in the pathology of female infertility during implantation, pregnancy, and abortion. In the uterus, MCT subtype is abundant in myometrium and adjacent basal layer while MCTC subtype is distributed in all layers. MCs in response to hormones mainly estradiol and progesterone become activated and release a wide range of mediators including histamine, VEGF, proteases, and metalloproteinases (MMPs) that have a role in different stages of pregnancy. An increasing influx of MCs to the cervix during the pregnancy occurs that helps to the physiologic cervical ripening. While MMPs degrade the extracellular matrix (ECM), VEGF modulates neovascularization and histamine influences the embryo implantation. MC-derived histamine may have a positive effect during implantation due to its participation in tissue remodeling. MC proteases including tryptase and chymase activate the precursors of MMP2 and MMP9 to mediate ECM degradation during the physiologic menstrual cycle. There is a line of evidence that MCs have a role in abortion by releasing TNF-α.

Homogeneous charge compression ignition (HCCI) combustion phasing control is one of the most difficult challenges of operating this new concept of combustion. In this study, a dimethyl ether (DME)/natural gas (NG) blend fuel HCCI engine is simulated to investigate the effect of DME additive on the control of a NG HCCI start of combustion (SOC) timing. The studies are carried out in two sections. Firstly, different mole fractions of DME from 0 to 0.25% are thoroughly examined. In the second part, the effect of general equivalence ratio on the combustion phasing is studied. Moreover, in both sections, the studies are mainly focused on the influence of these two parameter variations on the SOC timing, auto-ignition temperature, heat flux, and heat capacity ratio. A 3D computational fluid dynamic AVL FIRE code coupled with CHEMKIN is adopted to simulate the HCCI combustion. Results showed that while DME amount increases in the mixture, a two-stage heat release rate would appear. DME additive can advance SOC and reduce requiring inlet temperature. Adding only 5% of DME would lead to 6.7-CAD change in SOC. Heat capacity ratio would lead to higher in-cylinder temperature during compression stroke, while equivalence ratio rises. 2.4 CAD change in SOC occurred for increasing equivalence ratio from 0.25 to 0.4.

A low cost alkaline catalyst of dolomite (CaMg(CO3)2) was used to stabilize acacia sawdust bio-oil mixed with methanol. The upgrading efficiency was evaluated in terms of the total acid number (TAN) and viscosity. A change in the dolomite calcination temperature from 700 to 900 °C led to a significant change in the TAN and viscosity of the methanol-added bio-oil. Dolomite activated at higher temperatures had larger amounts of active CaO and MgO species due to the enhanced decarboxylation of calcium and magnesium carbonates. An increase in the dolomite content (1-5 wt%) decreased the TAN value of bio-oil remarkably. A thermal aging test of the methanol-added bio-oil upgraded using dolomite (calcined at 900 °C) at 50 °C for 24 h was carried out by storing the bio-oil at 80 °C for one week. Although the TAN value increased after the aging process, it was still lower than the TAN of raw bio-oil. In addition, increasing the methanol content (10-30 wt%) decreased the TAN and viscosity of the bio-oil significantly.

Co-feeding a hydrogen-rich material with biomass feedstock is an effective approach to enhance the pyrolysis process efficiency. In this research, the effect of methane (H/C eff ratio of 4) co-feeding on product selectivity of catalytic pyrolysis of lignin and yellow poplar was studied at 600 °C using HY and HZSM-5/metal-modified HZSM-5 as in-situ and ex-situ catalysts, respectively. Fe, Cu, Zn, and Mo with a 3 wt% loading and Ni with 1, 3, and 5 wt% loadings were incorporated into HZSM-5 by incipient wetness impregnation method. Compared to the nitrogen pyrolysis atmosphere, methane enhanced significantly the level of hydrocarbon (BTEX, benzene derivatives and polyaromatics) production from the cellulose and hemicellulose fractions of biomass. Lignin was selectively converted to alkylphenols in catalytic pyrolysis under methane atmosphere. The maximum hydrocarbon yield of 5.86 wt% was obtained from catalytic pyrolysis of yellow poplar using HY ( in-situ ) and 1 wt% Ni/HZSM-5 ( ex-situ ) as catalysts, mainly due to the effects of Ni on enhanced methane activation and an increase in the acid site density of HZSM-5. Meanwhile, the coke content of HZSM-5 was increased in both lignin and yellow poplar pyrolysis by replacing the pyrolysis atmosphere of nitrogen with methane.

Ultraviolet (UV) radiation as an environmental factor alters the physiological and metabolic processes in plants. Manganese (Mn) is an essential element that is required for plant growth and development. This experiment was conducted in order to determine the effects of Mn supply and UV radiation on the physiological and metabolic responses in Mentha aquatica. With this aim, three levels of Mn and UV treatments were used as follows: basic Hoagland’s nutrient solution without UV radiation (control), Mn supply (100 μM), UV radiation (2 h daily), and UV + 100 μM Mn. After three weeks of treatments, the root and shoot dry weights and the contents of photosynthetic pigments were decreased under UV radiation condition. However, the contents of flavonoids, soluble carbohydrate, anthocyanins, malonaldehyde (MDA), hydrogen peroxide (H2O2), and the activity of antioxidant enzymes (superoxide dismutase, catalase, and peroxidase) were increased. Interestingly, Mn at 100 μM concentration decreased the harmful effects of UV radiation on M. aquatica. In addition, the clear differences were observed in the terpene constituents of M. aquatica after the Mn and UV treatments. In this study, 1, 8-cineole, menthofuran and β-caryophyllene were the most abundant constituents of essential oils in both the control and treated plants. The correlation analysis between pairs of the primary and secondary metabolites showed that there were positive and negative correlations among the variables under the Mn supply and UV radiation conditions. These findings clearly display a positive effect of external Mn up to 100 μM in the nutrient solution on the resistant of M. aquatica to UV radiation.

Thermal and in-situ catalytic pyrolysis of lignin were carried out in a bench-scale pyrolyzer. The yield and composition of the bio-oil produced were influenced largely by the type of lignin samples, pyrolysis temperature, and nitrogen carrier gas flow rate. The highest bio-oil yield of 35.95 wt.% was achieved using kraft lignin at 500 °C and a carrier gas flow rate of 600 ml/min. In-situ catalytic pyrolysis resulted in a decrease of the bio-oil yield, but the aromatic product distribution was altered greatly depending on the types of catalysts. In-situ catalytic pyrolysis also showed enhanced selectivity to valuable aromatic hydrocarbons.

The essential oils of Tanacetum parthenium (L.) Schultz. Bip. and Tanacetum punctatum (Desr.) Grierson. leaves were obtained by hydrodistillation and analysed by GC and GC-MS. The oil yields (v/w) ...

Tungstated zirconia (WO3/ZrO2 with WO3 loadings of 9.9 (WZ9.9), 15.5 (WZ15.5), and 15.7 wt% (WZ15.7)) and Amberlyst (15, 35, 36, 39 and 45) catalysts were employed to upgrade pyrolysis bio-oil of acacia sawdust through an esterification reaction using methanol at atmospheric pressure and room temperature or 80 °C. The upgrading efficiency was evaluated by measuring the total acid number (TAN) and viscosity. The viscosity and TAN of the resulting upgraded bio-oil were found to be dependent on the calcination temperature of the WO3/ZrO2 catalysts. At room temperature, the largest decrease in viscosity and TAN of the bio-oil and methanol mixture was obtained using WZ9.9 tungstated zirconia calcined at 900 °C. An increase in reaction temperature to 80 °C improved the flowability and TAN of the methanol-added bio-oil using WZ9.9 activated at 900 °C. The product distribution of the bio-oil upgraded using methanol revealed esterification to be the dominant reaction pathway under the reaction conditions of this study. When the ether extracted bio-oil was upgraded at 80 °C using methanol over catalysts, the Amberlyst catalysts were found more effective than tungstated zirconia catalysts in enhancing the esterification reaction and reducing TAN.

The essential oil (obtained by hydrodistillation) and hexane extracts (obtained by Soxhlet apparatus) of Chaerophyllum macropodum (Boiss.) from two different area were analyzed by GC and GC-MS. The essential oil of C. macropodum from Givi (sample A) and Neor (sample B) localities were characterized by a dominant amount of trans-β-ocimene (22.8% and 21.2%), cis-β- ocimene (10.0% and 8.5%) and (+) spathulenol (4.4% and 6.0%), respectively. p-cymene (10.3%), γ-terpinene (9.2%), trans-β-farnesene (8.2 %) and fenchyl acetate (6.5%) among the 27 components of the total oil in Givi sample were detected. Caryophyllene oxide (9.0%), α-pinene (7.1%), β- caryophyllene (6.6%), myristicin (5.1%) and sabinene (5.0%) were predominated in the oil obtained from Neor sample. In the hexane extracts of sample A and B the following compounds were detected, respectively: linoleic acid (23.2% and 29.2%), 6-octadecenoic acid (20.2% and 6.8%), 9, 12-octadecadienoic acid (8.8% and 9.9%) and E-β-farnesene (4.6% and 8.7%). C...

In this research, Ni-based catalysts with different supports (HBeta and HZSM-5) were prepared via the impregnation method and subsequently tested for the catalytic hydrodeoxygenation (HDO) of crude pyrolysis oil (CPO) using supercritical methanol (MeOH). The Ni/HBeta showed a better catalytic performance than Ni/HZSM-5, resulting in a 43.81% deoxygenation degree of CPO. In addition, the ether extraction of CPO was carried out to remove its heavy fraction and improve the efficiency of the upgrading process. A high-quality refined oil was achieved after using the combined physicochemical treatments of ether extraction and supercritical catalytic HDO. The upgrading efficiency was evaluated in terms of the degree of deoxygenation, carbon residue value, water content, higher heating value, and distribution of products. The effect of the type of supercritical solvent on the catalytic HDO performance of Ni/HZSM-5 was evaluated by replacing MeOH with ethanol (EtOH). The results showed that when MeOH was substituted with EtOH, the yields of the gaseous and solid products were significantly reduced, while the yield of liquid products was considerably increased. Meanwhile, the content of coke deposited on the catalysts was analyzed using thermogravimetric analysis, and the coke compositions were evaluated using Fourier-transform infrared (FTIR) spectroscopy. While the minimum catalytic coke content was obtained using Ni/HBeta in the supercritical HDO of CPO, the minimum coke content was observed using Ni/HZSM-5 in the upgrading of ether-extracted pyrolysis oil (EEPO). The FTIR results revealed that the coke deposited on the catalysts was mainly formed through condensation, rearrangement, and hydrogen transfer mechanisms.

The purpose of this paper is to study the molecular dynamics simulation of phosphorus tribromide (PBr3) as the condensed inorganic liquid. To this aim, four regional intermolecular potential functions of phosphorus tribromide in the gas phase were considered. The potential energy data of 9 phosphorous tribromide configuration dimers were calculated at the B3LYP/6-31 + G (d) level of theory. The calculated potential data were employed to construct a 4-site all-atom force field model. Then, the force field parameters were used to perform the molecular dynamics simulations and compared the simulation results with experimental data. Quantitative agreements for the atomic number density, internal energy, enthalpy, heat capacity and radial distribution function over a wide range of experimental conditions were obtained as a consequence of the parameters force field validation without using experimental data a priori.

Catalytic hydrogenation is considered as an efficient technique for upgrading pyrolysis bio-oil. High flammability of hydrogen gas in contact with air leads to difficult control of high pressurized hydrogen gas in large-scale systems. Meanwhile, molecular hydrogen production is a costly industrial process. Thus, hydrogenation study using hydrogen donor (H-donor) material as alternative for hydrogen gas could be useful in terms of cost and safety control. In this study, the potential of decalin and tetralin for use as hydrogen source was investigated in transfer hydrogenation of renewable lignin-derived phenolic compounds (phenol, o-cresol and guaiacol) and a simulated phenolic bio-oil over Pd/C and Pt/C catalysts. Reaction mechanisms of H-donor dehydrogenation and phenolics hydrogenation were studied. Catalytic activity of Pt/C for transfer hydrogenation of the phenolic compounds was higher than that of Pd/C at reaction temperature of 275 °C. Decalin as hydrogen source showed to be more efficient for hydrogenation of the phenolic compounds compared to tetralin. In addition, the influence of water content on transfer hydrogenation activity was studied by employing the water to donor ratios of 0/100, 25/75, 50/50 and 75/25 g/g. Maximum hydrogenation of phenol as bio-oil model compound was observed at water to donor ratio of 50/50 g/g.

In this study, microwave assisted hydrodistillation (MAHD) technique was successfully used to separate volatile essential oils from flowers and leaves of Marsdenia erecta. The obtained oils were subsequently analyzed using the gas chromatography combined with the mass spectrometry (GC-MS) technique. A total of 19 and 15 compounds were identified in the profiles of flowers and leaves, constituting 93.5 % and 90.6 % of the chemical profiles, respectively. Our study revealed the presence of high quantities of linalool in the extracted oils. Additionally, in both oils, oxygenated monoterpenes were the most abundant natural compounds, while the second and third ranks were due to non-terpene hydrocarbons and oxygenated diterpenes, respectively.

Mesoporous ceria, which was synthesized under supercritical conditions, was found to be an effective support material of Ni catalyst for the in-situ hydrogenation of m-cresol (a representative compound of bio-oil) using secondary alcohols of 2-propanol (2-PrOH) and 2-butanol (2-BuOH) as a hydrogen source (H-donor) to produce 3-methylcyclohexanol, 3-methylcyclohexene, and methylcyclohexane under a H2 gas-free atmosphere. The activities of different metal catalysts (Ni, Cu, and Co) for the in-situ hydrogenation of m-cresol were examined using 2-PrOH as a H-donor. Total and effective conversion of m-cresol achieved only over Ni/CeO2 because of its fair catalytic properties, as determined by N2 adsorption-desorption, hydrogen temperature-programmed reduction, ammonia temperature-programmed desorption, X-ray diffraction, and transmission electron microscopy. The dependence of Ni/CeO2 performance on the reaction time (4–6 h) and Ni loading (3–9 wt%) was examined from the in-situ hydrogenation of m-cresol with 2-PrOH. The deactivation test of Ni/CeO2 was performed by reusing the spent catalyst, which was then regenerated through successive oxidation and reduction, several times in the m-cresol transformation employing 2-PrOH as a H-donor. In addition to m-cresol, other phenolic model compounds of bio-oil, such as anisole, phenol, and guaiacol, were also treated by in-situ hydrogenation with 2-PrOH over Ni/CeO2. Although this catalyst was effective for phenol and guaiacol transformation, it was relatively ineffective for anisole conversion. The in-situ hydrogenation of crude bio-oil with 2-PrOH and 2-BuOH was accomplished over the Ni/CeO2 catalyst, resulting in a refined bio-oil with a 37.5–38.9% lower oxygen content and a high heating value (HHV) of up to 25 MJ/kg.

Lignocellulosic biomass is an abundant renewable energy source that can be converted into various liquid fuels via thermochemical processes such as pyrolysis. Pyrolysis is a thermal decomposition method, in which solid biomass are thermally depolymerized to liquid fuel called bio-oil or pyrolysis oil. However, the low quality of pyrolysis oil caused by its high oxygen content necessitates further catalytic upgrading to increase the content of oxygen-free compounds, such as aromatic hydrocarbons. Among the three different types of lignocellulosic biomass components (hemicellulose, lignin, and cellulose), lignin is the most difficult fraction to be pyrolyzed because of its highly recalcitrant structure for depolymerization, forming a char as a main product. The catalytic conversion of lignin-derived pyrolyzates is also more difficult than that of furans and levoglucosan which are the main pyrolysis products of hemicellulose and cellulose. Hence, the main purpose of this study was to develop a bench-scale catalytic pyrolysis process using a tandem catalyst (both in-situ and ex-situ catalysis mode) for an efficient pyrolysis and subsequent upgrading of lignin components. While HZSM-5 was employed as an ex-situ catalyst for its excellent aromatization efficiency, the potential of the low-cost additives of bentonite, olivine, and spent FCC as in-situ catalysts in the Kraft lignin pyrolysis at 500 °C was investigated. The effects of these in-situ catalysts on the product selectivity were studied; bentonite resulted in higher selectivity to aromatic hydrocarbons compared to olivine and spent FCC. The reusability of HZSM-5 (with and without regeneration) was examined in the pyrolysis of lignin mixed with the in-situ catalysts of bentonite, olivine, and spent FCC. In the case of using bentonite and spent FCC as in-situ catalysts, there were no obvious changes in the activity of HZSM-5 after regeneration, whereas using olivine as in-situ catalyst resulted in a remarkable decrease in the activity of HZSM-5 after regeneration.

Background and Purpose: Vulvovaginal candidiasis is one of the most common infections in female genital organs, which is caused by Candida species. Candida albicans is the causative agent of more than 80% of infections, and the role of non-Candida strains in the disease etiology is less prominent. The expansion of Azoles resistance among C. albicans strains is considered an important medical problem. According to previous studies, Vitex agnus-castus (vitex) has some antimicrobial effects. We aimed to evaluate the anti-fungal effects of aqueous and alcoholic extracts of vitex against clinical vaginal isolates of C. albicans in comparison with fluconazole. Materials and Methods: Gas chromatography-mass spectrometry analysis was performed on vitex to identify its possible bioactive components. Forty C. albicans clinical isolates were identified by using germ tube, chlamydospore production, culture on CHROMagar, and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Finally, after the extraction of vitex, drug susceptibility test was carried out according to the clinical laboratory standards institute (CLSI) M27-S4 document guidelines. Results: The major chemical components of vitex leaf as determined by gas chromatography included α-Pinene, isoterpinolene, caryophyllene, and azulene. The minimum inhibitory concentrations (MICs) of aqueous and alcoholic extracts of vitex, as well as fluconazole were within the ranges of 15.62–62.5, 7.81–15.62, and 0.25–8 μg/mL, respectively. Conclusion: Our findings showed that the alcoholic and aqueous extracts of vitex had antifungal activity against clinical isolates of C. albicans. Moreover, the alcoholic extract of vitex and fluconazole were more effective against clinical vaginal isolates of C. albicans compared to the aqueous extract of vitex.

The hexane extract of the flower Rheum ribes L., which was collected from north-western Iran, was obtained by Soxhlet apparatus, and the essential oil composition was obtained by hydro distillation and analyzed by using GC-GC/MS. The extract from the flowers was characterized by a high amount of unsaturated fatty acids (UFA) (66.0 %) and some long chain hydrocarbon compounds. The main components of the hexane extract were 9-octadecenoic acid (ω-9) (42.8 %), 9, 12-octadecadienoic acid (linoleic acid or ω-6) (19.6 %), hexadecanoic acid, (palmitic acid) (8.6 %), 1,2-benzenedicarboxylic acid diisooctyl (5.7 %), dodecane (3.7 %) and γ-linolenic acid (3.6 %). The hexane extract from the Rheum ribes flowers detected an important source of ω-6 and ω-9 compounds. This study revealed that the flowers of this plant have a good source of oily components, especially the essential ones. It also showed that the flowers have natural source of unsaturated fatty acids. Twenty three compounds representing 97.5% of t...

Chemical characteristics, fatty acid composition, antioxidant and antimicrobial activities of the kernel of Prunus armeniaca L. were evaluated in this study. The hexane extracts of kernel of P. armeniaca, which were collected from northwestern Iran, were obtained by Soxhlet apparatus. The fatty acids were derived to methyl esters and determined by gas chromatography/flame ionization detector and gas chromatography/mass spectrometry systems. The oil from kernel extract contained ω-6 (51.6 %). The other main components were hexadecanoic acid (palmitic acid) (23.0 %), octadecanoic acid (stearic acid) (10.6 %) and 9-hexadecenoic acid (2.7 %). Hexane extract of kernels from P. armeniaca was detected as an important source of ω-6 compound. The antioxidant activity of the extract was evaluated by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) method. The results indicate that hexane extract from P. armeniaca kernels possesses considerable antioxidant activity. The IC50 value in the DPPH assay was 165 μg/ml. The antimicrobial activity of the extract was determined against some Gram-positive and Gram-negative bacteria (Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae), as well as three fungi (Candida albicans, Saccharomyces cerevisiae and Aspergillus niger). The bioassay showed that the oil exhibited moderate antimicrobial activity. The present study reveals that the hexanic extract from kernel of this fruit is attractive sources of ω-6.

Rapid deactivation of zeolites caused by high formation and deposition of coke is a great challenge in catalytic conversion of biomass materials into value-added chemicals and fuels. The main purpose of this work was to reduce the formation of both types of thermal and catalytic coke over zeolites. It was revealed that there is a significant interaction between zeolite pore structure and the density of acid sites which could be optimized for reduced coke formation. In this study, catalytic pyrolysis of cellulose was conducted using HZSM-5 (Si/Al: 30), HY (Si/Al: 30) and physically mixed catalysts of HZSM-5 (Si/Al: 30) and dealuminated HY (Si/Al: 327). Coke formation over the physically mixed catalysts was remarkably lower than that over HZSM-5 and HY; the coke contents of HZSM-5, HY and physically mixed catalysts of HZSM-5 and dealuminated HY with a ratio of 70:30 wt% were 7.01, 11.47 and 4.82 wt%, respectively. The aromatic hydrocarbon yield was also considerably enhanced over the physically mixed catalysts compared to HZSM-5 and HY; the aromatic hydrocarbon yields achieved over HZSM-5, HY and the mixture of HZSM-5 and dealuminated HY (70:30 wt%) were 20.31, 8.91 and 27.01 wt%, respectively. This study shows that the interactive effects of zeolite characteristics such as pore structure and acidity could be taken into account for designing more efficient catalysts to achieve lower coke formation and higher production of desired products.

The objective of this study was to evaluate the potential use of the fruits of Trigonosciadium brachytaenium in the pharmaceutical and food industries. Flavonoids are present in food and medicinal plants and are thus consumed by humans. They are often found in plants as glycosides. Their biological activities have an impact on human health so that they serve as target molecules to develop new drugs. From the methanolic extract of the fruit of T. brachytaenium (Boiss.) Alava. (Umbelliferae), two flavonoid derivatives namely 5-hydroxy-3′-methoxy-4′-ethoxyflavone-7– O- [(4‴-acetyl) rhamnosyl (1 → 2) rhamnoside)], a luteolin derivative ( 1 ) and 5-hydroxy-4′-methoxy-8-ethoxyflavone-7- O- [(2‴-acetyl) rhamnosyl (1 → 2) rhamnoside)], an apigenin derivative ( 2 ) have been isolated by column chromatography (CC) and preparative TLC (PTLC). Their structures were elucidated by UV, 1 H and 13 C NMR, HMBC, NOE, EI-MS and IR spectra. The antioxidant activity of methanol extract was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. The results indicate that the methanol extract from the fruits possess considerable antioxidant activity (IC 50 = 47 μg/mL). This study reveals that the methanolic extract of this plant is attractive sources of flavonoids, especially the essential ones, as well as of effective natural antioxidants. The antimicrobial activity of the methanol extract of the fruit was determined against seven Gram-positive and Gram-negative bacteria ( Bacillus subtilis , Enterococcus faecalis , Staphylococcus aureus , Staphylococcus epidermidis , Escherichia coli , Pseudomonas aeruginosa and Klebsiella pneumoniae ), as well as three fungi ( Candida albicans , Saccharomyces cerevisiae and Aspergillus niger ). The bioassay showed that the extract exhibited good antimicrobial activity. These flavonoid compounds were isolated for the first time from T. brachytaenium .

Flavonoids are a large class of polyphenols, with more than 4000 combinations and have some very important medicinal and biological activity, especially antiradical, antioxidant, and to prevent cancer effects. In this study, two luteolin derivatives have been isolated from the aerial parts of Achillea tenuifolia and purified by column chromatography, TLC, and preparative TLC techniques to yield compounds. The chemical structures were determined by 1H NMR, 13C NMR, HMBC and IR spectroscopy techniques and were established as 5-hydroxy-3′,4′-dimethoxyflavone-7-O-(rhamnoside) (1) and 5-hydroxy-3′-methoxyflavone-4′-O-(penthenyl-4-one)-7-O-(2″-(rhamnosyl) rhamnoside) (2). The structure of the compounds was determined by spectroscopic techniques and by comparison with published data. The antimicrobial activity of the methanol extract was tested against three different bacteria by disc diffusion method and showed maximum inhibitory activity against Gram-positive bacteria, especially Bacillus subtilis.

This paper provides an insight into a new biotechnological method based on calcite precipitation for achieving high strength bio-concrete durability. It is very clear that mineral precipitation has the potential to enhance construction material resistance towards degradation procedures. The appropriate microbial cell concentration (30 ∗ 105 cells/ml) was introduced onto different structural concrete grades (40, 45 and 50 MPa) by mixing water. In order to study the durability of structural concrete against aggressive agents, specimens were immersed in different types of acids solution (5% H2SO4 and HCl) to compare their effects on 60th, 90th and 120th day. In general, sulphuric acid and hydrochloric acid are known to be the most aggressive natural threats from industrial waters which can penetrate concrete to transfer the soluble calcium salts away from the cement matrix. The experimental results demonstrated that bio-concrete has less weight and strength losses when compared to the ordinary Portland cement concrete without microorganism. It was also found that maximum compressive strength and weight loss occurred during H2SO4 acid immersion as compared to HCl immersion. The density and uniformity of bio-concrete were examined using ultrasonic pulse velocity (UPV) test. Microstructure chemical analysis was also quantified by energy dispersive spectrometer (EDS) to justify the durability improvement in bacterial concrete. It was observed that less sulphur and chloride were noticed in bacterial concrete against H2SO4 and HCl, respectively in comparison to the ordinary Portland cement concrete due to calcite deposition.

The methanol and n-hexane extract of Zosimia absinthifolia (Vent.) Link. (family: Umbelliferae) were investigated for their chemical composition. The compositions of methanol extract were separated by CC and TLC methods and those structures were elucidated by UV, 1H- and 13C-NMR, HMBC, and IR spectra. Three flavonoid components were identified in the methanol extracts of the Z. absinthifolia. The hexane extract was analyzed by GC and GC/MS. Sixteen compounds representing 94.5 % of the hexane extract were identified, among them n-octyl acetate (36.7 %), octyl propanoate (32.5 %), decane (3.5 %), angelicin (3.4 %) and umbelliferone (2.8 %) were the major constituents.

The essential oil composition of the seeds of Arnebia linearifolia was obtained by hydro distillation and the hexane extract was obtained by Soxhlet apparatus and analyzed by using GC and GC-MS. Twenty- one compounds representing 96.4 % of the distilled oil of A. linearifolia were identified, among them β-copaene (24.1 %), octyl acetate (23.6 %), cis-β-ocimene (9.9 %), α-pinene (6.1 %), β-cedrene (4.5 %), osthol (3.7 %) and clovene (3.3 %) were the major constituents. The hexane extract was characterized by higher amount of linolenic acid (ω-3) (45.4 %), linoleic acid (ω- 6) (21.8 %) and 6, 9, 12- octadecatrienoic acid (10.3 %). Hexane extract of seeds from A. linearifolia detected as an important source of ω-3 and ω-6 compounds. The antioxidant activity of the essential oil and extract were evaluated by DPPH method. The results indicate that hexane extract of this plant possess considerable antioxidant activity. The antimicrobial activity of the essential oil and extract was determined against so...

The hydrodeoxygenation of guaiacol, as a pyrolysis oil representative model compound, was carried out over a Pd/C catalyst using a liquid hydrogen source of 2-propanol (2-PrOH) as an alternative to hydrogen gas. The effects of reaction temperature (190–230 °C), initial nitrogen pressure (0.5–12 bar), Pd loading amount (5 and 10 wt%), catalyst content (0.2–0.5 g), and reaction time (1–6 h) on the product distribution were investigated. Generally, 2-methoxycyclohexanone (two-oxygen-containing compound), methoxycyclohexane, cyclohexanol, 2-methyl-2-cyclohexen-1-ol, 2-cyclopenten-1-one, cyclohexanone, 2-cyclohexen-1-ol, phenol (one-oxygen-containing compounds), and (1-methylpropyl)cyclohexane (oxygen-free compound) were produced during the transfer hydrogenation of guaiacol in 2-PrOH. The feasibility of using different types of alcohols, primary (methanol, ethanol, 1-propanol, and 1-butanol) and secondary (2-propanol, and 2-butanol), as a substitute for hydrogen gas in the guaiacol hydrodeoxygenation process was examined, and it was found that only the secondary alcohols could act as a H-donor for the guaiacol transformation over Pd/C. Both 2-PrOH and 2-butanol (2-BuOH) led to almost complete conversion of guaiacol (≥98.5 wt%). However, complete deoxygenation of guaiacol to (1-methylpropyl)cyclohexane only occurred when 2-PrOH was used as the reducing agent. Finally, the transfer hydrogenation of raw pyrolysis oil was carried out over Pd/C at 230 °C and an initial nitrogen pressure of 8 bar for 4 h using 2-PrOH and 2-BuOH as the H-donors. Although 2-PrOH was the most efficient H-donor for guaiacol hydrodeoxygenation, 2-BuOH led to a higher level of deoxygenation of pyrolysis oil, resulting in a greater heating value.

This study investigated two indigenous micro-organisms that can be isolated from soil. The isolated micro-organisms could precipitate calcium carbonate. These micro-organisms were applied to design self-healing concretes. Concrete is one of the most important materials which is used to build structures. Strength and durability of concrete is very important. Hence, a lot of research in this field is being conducted. Although a few reports can be found on the use of different micro-organism to design self-healing concretes, no research has been carried out to isolate suitable indigenous micro-organisms in Malaysia. In this study two strains of microorganisms were isolated from soil. Broken concrete was treated by a medium culture (MC) containing micro-organisms. Results of this study showed that, cracked concrete could be filled by calcium carbonate after treating by a MC containing micro-organisms. However, this treatment is not very effective on the strength of concrete. Results of this study can ...

Background: Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. Objectives: Development of the drug resistance is becoming a threat to disease control, which underscores need for new agents targeting M. tuberculosis. Materials and Methods: In this study, analysis of gene expression was performed using real-time polymerase chain reaction (RT- PCR). Results: Results of the current study showed that the minimum inhibitory concentration value of cinnamaldehyde against M. tu- berculosis was 200 g/mL. Moreover, RT-PCR data showed that a total of 25 genes were regulated by the cinnamaldehyde. Of these, 12 genes were up-regulated, and 13 genes were down-regulated. Conclusions: Cinnamaldehyde is a pattern to expand the new anti-TB drugs, because the targets of the cinnamaldehyde are dier- ent from those of anti-tubercular agents.

Bifunctional metal/acid catalysts of 5 wt% Ni/HBeta, 5 wt% Fe/HBeta, 2.5 wt% Ni-2.5 wt% Fe/HBeta (NiFe-5/HBeta) and 5 wt% Ni-5 wt% Fe/HBeta (NiFe-10/HBeta) were used for hydrodeoxygenation (HDO) of a simulated phenolic bio-oil consisting of phenol (50 wt%), o-cresol (25 wt%) and guaiacol (25 wt%). Nickel and iron metals were supported on hydrogen form Beta zeolite (HBeta) under similar ion-exchange conditions. BET surface area and acid sites density of Ni/HBeta, Fe/HBeta, NiFe-5/HBeta and NiFe-10/HBeta were 463, 445, 455, 417 m2/g and 0.53, 0.48, 0.50, 0.38 mmol/g, respectively. Cycloalkanes (21.39 wt%) and aromatic hydrocarbons (20.21 wt%) were the dominant hydrocarbons obtained over monometallic catalysts of Ni/HBeta and Fe/HBeta through reactions of hydrogenation and hydrogenolysis, respectively. It was revealed that both hydrogenation and hydrogenolysis mechanisms were effectively proceeded over the bimetallic catalyst of NiFe/HBeta which showed enhanced HDO efficiency compared to monometallic catalysts of Ni/HBeta and Fe/HBeta due to the synergistic effect between the two metals. The effect of reaction temperature on HDO efficiency of NiFe-10/HBeta catalyst was investigated at 220, 260, 300 and 340 °C. Maximum catalytic activity and hydrocarbons selectivity was observed at 300 °C. Replacement of water with methanol as solvent in HDO of the simulated phenolic bio-oil over NiFe-10/HBeta remarkably reduced the selectivity towards hydrocarbons.

Conversion of lignin to aromatic hydrocarbons over zeolites is a challenging issue due to low reactivity of lignin-derived phenolic compounds over zeolites as well as their high potential for strong adsorption on zeolite acid sites. Hence, pure zeolites are not appropriate catalysts for upgrading of the lignocellulosic biomass with high content of lignin. In this research, a bifunctional Fe/HBeta catalyst showed to be efficient for production of aromatic hydrocarbons in catalytic pyrolysis of palm kernel shell waste with a high lignin content of about 50 wt%. Lignin-derived phenolics were deoxygenated through a hydrogenolysis reaction promoted by Fe active sites. A comparison between catalytic behaviour of HBeta and HZSM-5 in conversion of palm kernel shells showed that catalyst deactivation via occupation of zeolite acid sites by lignin-derived phenolics is affected by catalyst pore size and strength of zeolite acid sites. Meanwhile, cellulose and lignin were compared in terms of reactivity over zeolite acid sites and influence on zeolite deactivation. It was also shown that the yield of aromatic hydrocarbons obtained from conversion of lignin was remarkably enhanced by incorporation of iron into the HBeta structure. However, both HBeta and Fe/HBeta resulted in approximately similar aromatic yield from conversion of cellulose.

Pyrolysis bio-oil is recognized as a renewable and carbon-neutral fuel which could be a potential alternative for depleting fossil fuels. However, bio-oil is highly oxygenated and needs to be upgraded prior to be used as fuel additive. Catalytic hydrodeoxygenation (HDO) is an efficient technique for bio-oil upgrading. The reaction pathway for HDO of bio-oil is unknown since it is a mixture of hundreds of different compounds. The study on mechanism of transformation of these compounds could be helpful to propose an overall pathway for HDO of bio-oil. Phenols which are derived from pyrolysis of lignin fraction of biomass are considered as attractive model compounds for study of bio-oil HDO since they are highly stable in HDO reaction. Reaction pathway and product selectivity in HDO of phenols are highly affected by type of catalyst promoters and supports, catalyst preparation procedure, solvent type, chemicals used as co-feed and operating conditions (i.e., temperature and pressure). The effects of these factors on selective production of high-value hydrocarbons of aromatics and alicyclics from HDO of phenol, cresol, guaiacol and anisole are discussed in this review.

The chemical composition of essential oils obtained by hydrodistillation from the flower, leaf and stem of Falcaria vulgaris Bernh., which is endemic to Iran, were analysed by GC and GC/MS (samples were from two different localities: A from Ardabil and B from Khalkhal). α-Pinene was the major constituent in all the three oils (flower, leaf and stem) from sample A (43.8%, 33.0% and 50.9%, respectively). The oil of F. vulgaris flower was characterised by a higher amount of β-caryophyllene (25.2%) and 1,8-cineole (12.8%) among the eight components comprising 96.2% of the total oil detected. α-Terpinyl acetate (23.2%) and limonene (14.4%) predominated in the leaf oil. In the oils of sample B, α-pinene (16.1% in the flower oil, 31.5% in the leaf oil and 34.5% in the stem oil) was the major compound. Limonene (14.2%) and germacrene D (32.1%) were also the main constituents found in the leaf oil from sample B. α-Terpinyl acetate (21.9% in the leaf oil) and limonene (29.8% in stem oil) were the other major compounds obtained from this sample. Antibacterial activity was determined by the measurement of growth inhibitory zones.

A comparison of the chemical composition, antioxidant and antibacterial activity of the essential oils obtained from the leaves of Thymus caucasicus Willd., T. kotschyanus Boiss. & Hohen., and T. vulgaris (L.) were carried out. The oils were obtained by hydrodistillation and were analyzed by GC and GC-MS. Twenty constituents representing 94.8 % of the essential oil of T. caucasicus, twenty - nine components 96.6 % of the T. kotschyanus oil and twenty two compounds 98.2 % of the T. vulgaris leaf oils have been identified. The oil of T caucasicus leaf was characterized by higher amounts of 1,8-cineol (21.5 %), thymol (12.6 %), β-fenchyl alcohol (8.7 %), nerolidol (7.8 %), terpinolene (7.2 %), a-pinene (7.0 %) and myrcene (6.8 %). In the oil of T kotschyanus leave, carvacrol (24.4 %), β-caryophyllene (14.5 %), y-terpinene (12.4 %), a-phellandrene (10.8 %), p-cymene (9.8 %) and thymol (6.8 %) were the predominant compounds, while the main components of the oil of T vulgaris leaves were thymol (43.8 %...

The water distilled essential oils and n-hexane extract of Zosimia absinthifolia (Vent.) Link. (family: Umbelliferae) growing in Khalkhal, North-west Iran were analyzed by GC and GC-MS. The yields were: 0.2 % and 0.7 % (v/w) for essential oil and n-hexane extracts, respectively. Twenty-one compounds representing 96.0 % of the distilled oil of Z. absinthifolia were identified, among them octyl acetate (24.7 %), β-caryophyllene (22.2 %), cis-β-ocimene (8.9 %), α-pinene (5.3 %), clovane (5.3 %) and β-gurJunne (4.6 %) were the major constituents. The extracts was characterized by higher amount of butyl octanoate (31.4 %), octyl acetate (29.7 %), 6-methoxy-1- indanone (12.2 %) and osthol (4.4 %), sixteen components comprising 95.1 % of the total oil were detected in the extract. The oil obtained by hydrodistillation method consist mainly of aliphatic oxygenated and sesquiterpene constituents, whereas the extracts contain mainly aliphatic ester compounds.

The hexane extracts from root and seed of Chaerophyllum crinitum Boiss. which were collected from northwestern Iran, were obtained by Soxhlet apparatus. The fatty acids were derived to methyl esters and determined by gas chromatography/flame ionization detector (GC/FID) and gas chromatography/ mass spectrometry (GC/MS) systems. The extracts from the seed and root were characterized by a high amount of unsaturated fatty acids (UFA) (52.6% and 49.9%, respectively) and some of sesquiterpenoid compounds. The main components of the seed and root extracts were ω-3 (23.2 %and 18.5 %), 6-octadecenoic acid (20.2 and 14.3 %), carotol (16.9 %and 12.8 %), ω-6 (9,12-octadecadienoic acid) (8.8% and 6.4%) and (-)-β-acoradiene (5.1 %and 7.3 %)respectively. The hexane extract from seed of C. crinitum detected as an important source of unsaturated fatty acid compounds. The antimicrobial activity of the extracts of those samples were determined against seven Gram-positive and Gram-negative bacteria (Bacillus subtil...

Hydrodistillation of leaves and stems of Stachys byzantina C.Koch. (Lamiaceae) yielded 0.1 %and 0.08 %( v/w) essential oils, respectively. GC-MS analysis allowed identification of 15 components, which made up 94.6 % of the total oil from the leaves, while only 10 compounds (95.6 %) were identified in the stems. The main components of the leaf oil were germacrene- D (37.0 %), valeranone (11.9 %), n- nonadecane(6.8 %), 2-pentadecanone-6,10,14-trimethyl (6.5 %), β-elemene (6.4 %) and α-bisabolol (4.8 %). In the stem oil, the main constituents were nerolidol (57.8 %), thymol (19.0 %) and n-nonadecane (4.8 %). The antimicrobial activity was tested on six bacterial strains and two fungal strains, using the agar diffusion method. Diameters of growth inhibition zones were measured. The most sensitive microorganisms were, in order: Enterococcus faecalis > Pseudomonas aeruginosa > Klebsiella pneumoniae > Bacillus subtilis > Candida albicans (ATCC 10259) > Candida albicans (ATCC 24433) > Staphylococcus aure...

Hydrodistilled volatile oil from the aerial parts of Eremostachys azerbaijanica Rech.f. (Labiatae) was obtained at yield of 0.9 % v/w, based on dry weight. The oil was analyzed by a combination of GC and GC-MS. Thirty-six compounds were identified, representing 97.3 % of the total essential oil. The main constituents of the essential oil were carvone (64.5 %), limonene (12.4 %), β-bourbonene (2.4 %), germacrene-D (2.4 %), β-caryophyllene (1.2 %), trans-carveol (1.0 %) and cis-calamenene (1.0 %).

A high performance thermostable α-amylase at low pH values has been synthesized. Sugarcane bagasse was hydrolyzed in a dilute acid solution and utilized as carbon source for the growth of Aspergillus niger strain NCIM 548. Glucose, xylose and arabinose with the ratio of 1. 0: 0. 9: 0. 3 (w/w/w) were detected in the hydrolyzate by HPLC analysis. Optimization of the fermentation conditions for α-amylase production was performed by varying four influential parameters such as Sugarcane bagasse hydrolyzate (SBH), NH4Cl, pH and incubation time using a central composite design (CCD) under response surface methodology (RSM). The optimum values of SBH, NH4Cl, pH and incubation time were 20. 49, 2. 34 g/l, 5. 65 and 76. 67 h, respectively. The acido-thermophilic enzyme showed maximum stability at 70°C and pH value of 4. The rate constant, Km and maximum reaction rate, Vmax were 18. 79 g/l and 15. 85 g/l·min, respectively.

The air-dried roots of Chaerophyllum macropodum Boiss. were subjected to hydrodistillation for 4 h using a Clevenger type apparatus. The essential oil was analyzed by GC and GC-MS. Ten components were characterized, representing 96.3 % of the total components detected. The oil of the major constituents was identified as myristicin (39.2 %), terpinolene (23.1 %), trans-β-ocimene (21.9 %) and γ-terpinene (5.4 %).

The air-dried flowers of Chrysanthemum parthenium (L.) Bernh. were subjected to hydrodistillation for 3 h using a Clevenger type apparatus. The essential oil was analyzed by GC and GC-MS. Nineteen components were characterized, representing 98.9 % of the total components detected. The oil of the major constituents was identified as camphor (61.1 %), camphene (9.2 %), farnesol (4.6 %), bornyl acetate (3.5 %), chrysanthenon (3.1 %), and borneol (2.9 %). Antibacterial activity was tested against Gram-positive and Gram-negative bacteria using the agar diffusion method. Activity was observed against two Gram-positive and one Gram- negative bacteria.