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A particular attention should be paid to isolation, characterization, and assessment of bioactive flavonoids, especially for anti-arthritic activity. The slurry of adsorbent (silica gel; 60–120 lattice) was blended in n-hexane to form a uniform slurry, and this was then employed as a fixed-stage adsorbent. Butanolic solution (10 g) was dissolved in the minimum volume of butanol, and then adsorbed on silica gel (60–120 mesh) while still wet. The wet powder was then dried, and the separated liquid phase was collected and applied to the column to try to isolate possible phytoconstituents. A whole plate full of fractions was monitored simultaneously on a TLC plate with a mixture of chloroform:methanol:water (68:30:02) as the solvent system. Six fractions (F1-F6) were generated after the colours of F1 and F2 were mixed next to each other, and after Rf was discovered in F3. A separate group of six animals was created for the survey, which was made up of five treatment groups and one control group. It was concluded that yellow crystalline solid luteolin was obtained as a result, with the Shinoda test confirming that it was a flavonoid. The absorption of luteolin was discovered to be in an aqueous alkaline solution. There were five different resonances, occurring at different frequencies, in the 400 MHz 1H NMR spectrum: 7.00 (d, J = 13.5 Hz, 2H), 6.73 (s, 1H), 6.56 (s, 1H), 6.18 (s, 1H), 6.05 (s, 1H), 4.78 (s, 1H), 4.24 (s, 1H), 3.81 (s, 1H) (s, 1H). Inhibiting arthritic inflammation at doses of 40 mg/kg (luteolin) was significant (P

Clostridium acetobutylicum is an anaerobic bacterium that is extensively studied for its ability to produce butanol. Over the past two decades, various genetic and metabolic engineering approaches have been used to investigate the physiology and regulation system of the biphasic metabolic pathway in this organism. However, there has been a relatively limited amount of research focused on the fermentation dynamics of C. acetobutylicum. In this study, we developed a pH-based phenomenological model to predict the fermentative production of butanol from glucose using C. acetobutylicum in a batch system. The model describes the relationship between the dynamics of growth and the production of desired metabolites and the extracellular pH of the media. Our model was found to be successful in predicting the fermentation dynamics of C. acetobutylicum, and the simulations were validated using experimental fermentation data. Furthermore, the proposed model has the potential to be extended to represent the dynamics of butanol production in other fermentation systems, such as fed-batch or continuous fermentation using single and multi-sugars.

Integrating the acetone-butanol-ethanol fermentation with pervaporation or gas stripping for in situ product recovery is considered as an effective way for biobutanol production, and the following downstream distillation sequences have been extensively investigated. Whereas, there are still no comprehensive comparison of the reported distillation processes in sight of the techno-economic feasibility. In this study, three alternative distillation sequences that contains a decanter and recycle loops are selected and compared by steady-state simulation. ABE condensates collected by ISPR, with different solvent concentrations and constituents, are considered as the feed stream of distillation. The impact of ABE ratio on energy consumption and techno-economics of the selected distillation sequences are analyzed. Results indicate the separation performances, including the energy requirement and economics, are highly influenced by the distillation sequence. Compared with other Scenarios, when feeding the extreme ABE constituents within the confidence interval, the sequence that consisted of three columns and a decanter with two recycle loops exhibits the lower energy requirement (7.99 MJ/kg) and TAC (4.15 × 106 US $/yr). The current work guides to the designation of suitable ISPR-distillation process in future works.

The aerial parts of Haplophyllum tuberculatum (H. tuberculatum) have traditionally been used by local communities to treat fever, gastrointestinal disorders, worms, malaria and fractures, however, the responsible ingredients of the selected medicinal plant have not been identified. In the present study, antibacterial and antioxidant ingredients were isolated and characterized from the plant parts of locally grown H. tuberculatum, and their biological activity was evaluated. The powder aerial parts were extracted with methanol and the extract was successively fractionated with different polarities of solvents. All polarities of extracts (hexane, chloroform, ethyl acetate, butanol, methanol and water) were used to determine their antibacterial and antioxidant activity by established in-vitro method. The disk diffusion and free radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods were used to evaluate antibacterial and antioxidant activities of the prepared extracts and pure isolated compounds at different concentrations against three strains of Gram-positive and three Gram-negative bacteria. The antibacterial activity results showed that all prepared fractions and isolated pure compounds of the plant species gave significant activity against all Gram (+ and –) bacterial strains with the range of inhibition 0–20 mm. The antioxidant activity of the prepared extracts at all concentrations also showed substantial activity. Based on the highest activity, ethyl acetate and chloroform extracts were selected for the separation and isolation of antioxidant and antibacterial compounds by thin layer chromatography (TLC), column chromatography (CC), and preparative thin layer chromatography (PTLIC). The structure of the isolated antioxidant and antibacterial compounds from the ethyl acetate and chloroform extracts were determined on the basis of nuclear magnetic resonance (NMR) and mass spectra. The isolated pure compounds and active extracts could be used as a medicine for various infectious related diseases.

The article presents ecological characteristics of the Sulzer 6AL20/24 marine diesel engine fueled by a blend of n-butane and marine fuel. An important issue is the selection of the composition and methods of producing this fuel blend. The problem which have to be solved during selection of n-butanol content in the fuel blend for a specific engine, is to designate optimal mixture at the desired level of toxic compounds emission and particulates (under specific working conditions). Moreover the impact on the engine operation parameters must be as small as possible. The fuel blend composition selection problem was solved by analyzing the experimental data. On this basis a neural networks model and multiple regression models were built. It enabled the study of the effects and interactions between the model input values and the output variable.

In this study, alkali metal-doped sepiolite based catalysts were developed for the up-grading of ethanol through the Guerbet reaction mechanism. The catalysts were prepared by wetness impregnation with aqueous solution containing alkali metal precursors salts over calcined sepiolite, and finally activated at 500ºC in air. The catalysts have been characterized by XRD, SEM-EDS, TGA-DSC, N2-adsorption. In addition, TPD-CO2 and TPD-NH3 were used to determine the acid and basic characteristics of catalysts. The catalysts were tested into a quartz continuous gas-flow reaction system working at atmospheric pressure to investigate the effects of metal loading (wt%), the nature of the alkali metals and of the main reaction parameters (e.g., reaction temperature, weight hourly space velocity), on the production of n-butanol starting from ethanol. The highest yield (18%) was obtained at 400 ºC with the catalyst consisting in sepiolite, calcined at 500ºC, impregnated with 7 wt% of Cs. This study proves that ad hoc modified natural sepiolites with alkali metals are effective catalysts for the Guerbet upgrading of ethanol., The authors would like to acknowledge the Ministerio de Ciencia e Innovación of Spain (TED2021-130756B-C31).

The National NMR Facility is supported by FCT, ROTEIRO/0031/2013-PINFRA/22161/2016, co-financed by FEDER through COMPETE2020, POCI, and PORLandFCT through PIDDAC) and CERMAX(022162). The indole moiety is an important N-heterocycle found in natural products, and a key structural component of many value-added chemicals including pharmaceuticals. In particular, bis(3-indolyl)methanes (BIMs) are an important subgroup of indoles, composed of two indole units. Herein, we report the development of a simple method to access BIMs derivatives in yields of up to 77 % by exploiting a tBuOK-mediated coupling reaction of indoles and benzyl alcohols. publishersversion published

The middle vessel batch distillation column is an alternative to the regular batch distillation column. This configuration allows simultaneous separation of the light fraction (accumulated at top), heavy fraction (accumulated at bottom) and the intermediate fraction (accumulated in the middle vessel) in a single column. The objective of this article is to extensively analyse and discuss different control systems for the middle vessel batch distillation column (MVBDC) and dynamically optimize the column. Three control structures such as composition level cascade, composition temperature cascade, and temperature control system, have been tested and evaluated. Further, a dynamic optimization study has been performed on the control system providing the fastest separation. The optimizer is set to minimize the total energy consumed during the process. This resulted in a decrease in batch time from 26.8 to 25.2 h and a 13.5% decrease in overall energy usage. The presented dynamic optimization technique and control system design is useful for improving the performance of the MVBDC.

This study aims to investigate the density and viscosity of ternary biodiesel blends. Fuel density and viscosity play an important role in the fuel injection system, flame propagation, and combustion process in compression ignition engine. The density and viscosity of biodiesel are higher than high-speed diesel which is an implication in the commercialization of biodiesel. In the present study, palm oil has been used for the production of biodiesel through the ultrasound-assisted transesterification process. Three different types of fuel additives including butanol, dimethyl carbonate, and plastic oil have been used for the preparation of nine ternary biodiesel blends. The density and viscosity of individual fuels and ternary biodiesel were measured experimentally in a temperature range of 281.51 Ke348.15 K. For the prediction of density and viscosity of ternary biodiesel blends, four density and viscosity models were developed. The prediction accuracy of these developed models was assessed by a statistical tool absolute percentage error (APE). Newly proposed exponential regression models predicted well compared to experimental data for density and viscosity values with high regression coefficient 0.9995 and 0.9841 and lower mean absolute percentage of error 0.012 % and e 0.516 % at (348.15 K) temperature respectively. These correlations are significant for the automobile industry in developing fuel pipeline and transport equipment where additives would be present in diesel-biodiesel fuel blends.

The bioalcohol production (ethanol and butanol) from lignocellulosic biomass has some techno-economic limitations nowadays. Detoxification technologies can efficiently remove fermentation inhibitors (such as furan aldehydes, aliphatic acids, and phenolic compounds) to increase the bioalcohol titers. However, the addition of more steps before fermentation increases the complexity of the production scheme and reduces the profit margin. Process intensification concepts have been disseminated as a critical factor for the success of biotechnological processes, including bioalcohol production. Thus, this review discusses the main inhibitors from lignocellulosic biomass and the in-situ technologies used to minimize the yeast inhibition in hydrolysates and slurries. In-situ detoxification strategies involve different fundamentals, but they have the unanimity of allowing fermentation to be carried out concurrently. They are usually based on the establishment of a microbial consortium as well as the addition of reducing agents, polymers, solvents and adsorbents. Also, in-situ product recovery methods have been developed to minimize energy consumption in downstream processing.

Simultaneously producing acetone-butanol-ethanol (ABE) and decolorizing Methyl orange (MO) by fermentation with solid food waste (SFW) was studied. During the batch fermentation with MO concentration from 100 mgL−1 to 1000 mgL−1, carbon source utilization efficiency was above 93% with yields of acetone, butanol and ethanol being 0.13 gg-1, 0.23 gg-1 and 0.04 gg-1, respectively. During the repeated fermentation with the bagasse as the cell immobilization material, carbon source utilization efficiencies were all above 90% in the first 5 cycles fermentation. The maximum butanol and ABE concentration were 12.8 gL-1 and 22.1 gL-1, respectively. The solvent yield of acetone, butanol and ethanol were around 0.13 gg-1, 0.25 gg-1 and 0.06 gg-1, respectively. The MO decolorization had no negative effect on the ABE production and the decolorization efficiencies were all above 99% during batch fermentation or repeated fermentation with electrons transferred from intracellular to extracellular by mediator with the help of azo reductase to decolorize MO.

Unlike gaseous C1 feedstocks for acetogenic bacteria, there has been less attention on liquid C1 feedstocks, despite benefits in terms of energy efficiency, mass transfer and integration within existing fermentation infrastructure. Here, we present growth of Eubacterium limosum ATCC8486 using methanol and formate as substrates, finding evidence for the first time of native butanol production. We varied ratios of methanol-to-formate in batch serum bottle fermentations, showing butyrate is the major product (maximum specific rate 220 ± 23 mmol-C gDCW-1 day-1 ). Increasing this ratio showed methanol is the key feedstock driving the product spectrum towards more reduced products, such as butanol (maximum titre 2.0 ± 1.1 mM-C). However, both substrates are required for a high growth rate (maximum 0.19 ± 0.011 h-1 ) and cell density (maximum 1.2 ± 0.043 gDCW l-1 ), with formate being the preferred substrate. In fact, formate and methanol are consumed in two distinct growth phases - growth phase 1, on predominately formate and growth phase 2 on methanol, which must balance. Because the second growth varied according to the first growth on formate, this suggests butanol production is due to overflow metabolism, similar to 2,3-butanediol production in other acetogens. However, further research is required to confirm the butanol production pathway in E. limosum, particularly given, unlike other substrates, methanol likely results in mostly NADH generation, not reduced ferredoxin.

A ternary deep eutectic solvent was prepared using choline chloride, citric acid and glycerol. The effect of glycerol addition was investigated by means of freezing point, density, viscosity, conductivity, refractive index and pH measurements. Binary and ternary eutectic solvents showed a good catalytic performance in the esterification of acetic acid. For binary eutectic solvent composed of choline chloride and citric acid, acetic acid conversions of 52.46%, 50.00% and 47.86% were achieved at temperatures of 363, 358 and 353 K, respectively. Under the same conditions, the ternary eutectic solvent provided acetic acid conversions of 49.38%, 44.00% and 38.79%. Addition of glycerol caused a decrease in the freezing point from 303 to 241 K and also significant improvement in the physical properties that are important in catalytic applications., TUBITAK [213 M 643]; Ege University [15MuH009, EBLTEM 2015/BL/026], Authors acknowledge the support of TUBITAK (213 M 643), Ege University 15MuH009 and EBLTEM 2015/BL/026 scientific research projects.

A novel bio-based activated carbon was synthesized from vine shoot, an agricultural waste, by chemical activation method using NaOH as activating agent. Adsorption of acetone, butanol and ethanol (ABE), as main products in ABE fermentation, in the single and multicomponent systems were measured. The experiments were carried out in both equilibrium and dynamic conditions and selectivity of the adsorbent was calculated, accordingly. The adsorption kinetics of the synthesized adsorbent were also investigated. Based on the obtained results, the synthesized activated carbon (AC) shows a very high butanol loading (about 520 mg/g at 10 g/l butanol equilibrium concentration). High butanol selectivity over ethanol and acetone (10.31 and 7.66, respectively), obtained from multicomponent equilibrium experiments, indicated that the vine shoot based activated carbon showed the high affinity toward butanol. This result was also approved by ABE multicomponent breakthrough experiment in which adsorbed ethanol and acetone displaced by butanol during the adsorption process. High butanol capacity, fast equilibrium time, and excellent butanol affinity, makes the synthesized activated carbon a great candidate for butanol adsorption from ABE fermentation products.

Heterogeneous biocatalysts prepared by immobilizing recombinant lipases are promising for implementation in organic synthesis of various esters used as fragrances, emollients, emulsifiers, non-ionic surfactants, plasticizers, etc. For this research, the Thermomyces lanuginosus lipase produced by the authoring recombinant Pichia pastoris strain was adsorbed on the authoring macroporous carbon aerogel. The prepared biocatalysts were studied in the periodic processes of enzymatic esterification carried out in nonconventional anhydrous media of organic solvents at ambient conditions (22 ± 2 °C, 1 bar). Biocatalytical activities depended strongly on both the selected pair of lipase substrates (acid and alcohol) involved in reaction and the organic solvent used for esterification. The reaction rates of fatty C7 acid esterification with double and triple bond C3 alcohols, such as allyl and propargyl alcohols, were found to be 2–4 times lower than with aliphatic propanol. Isomerism of an acid (not alcohol) molecule greatly affected the esterification rates. It was observed that isomers of C4 and C5 acids (iso-butyric and iso-valeric) practically did not react with butanol. The esterification rates strongly depended on the polarity of the organic solvent characterized by the parameter logP. With an increase in the solvent polarity from non-polar hexane to polar acetone, the esterification rate decreased by two orders of magnitude. The prepared lipase-active biocatalysts had a sufficiently high operational stability under the chosen optimal reaction conditions; their stationary activity (300 ± 100 U·g–1) did not change in periodic reaction cycles during several tens of hours.

Understanding the activity of biomolecules in cosolvent systems is important for catalysis, separation and developing biosensors. The majority of previously studied solvents are either phase separated with water or miscible with water. Butanol was recently used to extract water for the conjugation of DNA to gold nanoparticles. In this work, the effect of butanol on the activity of a few RNA-cleaving DNAzymes was studied. A 130-fold improvement in sensitivity for the Na+ -specific EtNa DNAzyme was observed, and butanol also improved the activity of another Na+ -specific DNAzyme, NaA43T by a few folds. However, when divalent metal ions were used for both EtNa and 17E DNAzymes, the activity was inhibited. A main driven force for enhanced DNAzyme activity is the concentration effect due to butanol dehydration. This study provides insights into the interplay between DNA, metal ions and organic solvents, and such an understanding might be useful for developing sensitive biosensors.

The oleaster (Elaeagnus angustifolia L.) plant grown in three different locations in Nevsehir, Turkey was analyzed to determine its phenolic component profile, total phenolic compound, total carotenoid, total flavonoid, and antioxidant capacity values. Ultrasonic extraction of the oleaster’s flour, shell, core, flower, and leaf parts was carried out under solvent and acidic hydrolysis conditions using eight different polarity solvents (water, methanol, ethanol, acetone, ethyl acetate, butanol, petroleum ether, and hexane). The phenolic component profiles were determined using high-performance liquid chromatography with diode array detector (HPLC–DAD), and the main phenolic components in the oleaster samples were gallic acid, catechin, and their derivatives. At the same time, antioxidant properties of oleaster samples were evaluated by Folin–Ciocalteu (FC), ABTS, FRAP, DPPH, and CHROMAC methods. Various parts of oleaster, whose phenolic component content was determined in this study, are thought to be a natural source that can be used against degenerative diseases in future studies.

The leaves and fruits of Indonesian Syzygium spp such as white pakoba, red pakoba and bombongan have been extracted by ethanol. The ethanolic extract was partitioned with polar solvent gradient using n-hexane, ethyl acetate and n-butanol repeatedly. Each fraction was tested for antidiabetic activity and exhibited varying degrees of antidiabetic activity when tested with α-glucosidase method. Antidiabetic test indicated that the ethyl acetate and butanol fractions of the leaves of pakoba white, red pakoba and bombongan has potential as a source of active compounds.

Many of the African antimalarial ethno medicinal plants are good sources of promising antimalarial compounds. The stem bark of Plumeria alba Linn, was evaluated for in vivo chemosuppressive antimalarial activities in order to identify the most active solvent fraction from which antimalarial constituents can be isolated. The stem-bark of Plumeria alba Linn, family Apocynaceae was collected, air-dried, powdered, macerated in methanol and the extract concentrated in vacuo. The acute toxicity study was performed on the extract using Lorke’s method. The extract was thereafter tested for chemosuppressive antiplasmodial activities against Plasmodium berghei berghei NK65- infected mice using Peter’s four-day test at doses 100-800 mg /kg with normal saline (0.2 ml) and chloroquine (10 mg/kg) as negative and positive control drugs respectively. The average percentage parasitaemia, percentage chemosuppression and effective doses (ED50 and ED90), the survival times and percentage survivors elicited in all the mice were determined as indices of antimalarial activity. The active extract was subsequently partitioned successively into n-hexane, dichloromethane, ethyl acetate and butanol. The respective partitioned fractions with the aqueous phase were also tested as above at doses 0-80 mg/kg. All results were subjected to statistical analysis using ANOVA with Student Newman Keul’s post hoc test. Crude extracts of P. alba gave considerable reduction of percentage parasitaemia up to 200 mg/kg. The percentage chemosuppression at all doses, were significantly higher (p

The paper describes the properties of glycerol produced by transesterification, especially the ester content in the glycerol phase (ester losses) including the distribution of esters according to higher fatty acids. Glycerol, produced by transesterification of oil as a side product – the polar glycerol phase, is an important chemical raw material. The decreasing of ester losses is important because it (i) increases the ester yield and especially (ii) decreases the cost of glycerol purification. The transesterification of oils (rapeseed, olive, palm, sunflower and Camelina Sativa) with various distributions of fatty acids was carried out by methanol, ethanol and butanol including different transesterification stopping. The losses of ethyl and butyl esters are much higher than losses of methyl ester (approximately 2–3x). The distribution of ethyl and butyl esters in the glycerol phase is the same as in the ester phase, whereas distribution of methyl ester is different and depends on the way of transesterification stopping. The reason is the different polarity of methyl esters, which depends on the type of fatty acid. The polarity increases with increasing of double bonds, i.e. the most soluble is methyl ester of linolenic acid in the glycerol phase.

Flash point information is crucial for evaluating the fire and explosion (FE thus, their results are inapplicable to commercial mixtures of several liquids. In this study, two ternary mixtures, namely 1-butanol − acetic acid − ethylbenzene and 2-pentanol − acetic acid − ethylbenzene, were investigated. These mixtures comprise two binary constituents with minimum flash point behavior (MinFPB) and one binary constituent with maximum flash point behavior (MaxFPB). The ternary constituents do not exhibit MinFPB or MaxFPB; therefore, the aforementioned ternary mixtures can be considered the first known members of the fp 3.3.0−1b class ( Da Cunha et al., 2018 ). A model developed for ternary miscible mixtures was used to predict the flash point behaviors of the mixtures. The nonrandom two-liquid (NRTL), Wilson, original universal quasi-chemical functional-group activity coefficients (UNIFAC) and UNIFAC-Dortmund models were used to predict the activity coefficients of the binary and ternary constituents. The mixture of 1-butanol or 2-pentanol with acetic acid exhibited MaxFPB, indicating that acetic acid can substantially reduce the F&E risks of these alcohols. The findings can be applied in hazard identification, F&E hazard reduction, process safety design, fuel design, and the risk management of ignitable waste liquids.

A surge in biodiesel production has recently resulted in a surplus of crude glycerol, which has harmed the process' economy. Glycerol etherification with tert-butyl alcohol in the presence of acid catalysts for the generation of ethers (monoethers, diethers, and triethers) is highly recommended by many scientists. Series of phosphotungstic acid (10–60 wt%) supported bentonite (DTP/BNT) catalysts were prepared and evaluated their performances for etherification of glycerol with t-Butanol. The properties of prepared catalysts were investigated using XRD, (FTIR) flourier transform- infrared spectroscopy, SEM, EDX, TGA/DTA, and mercury porosimeter techniques. The study reveals that increasing reaction time for maximum production of di- and tri-glycerol ethers. Catalytic activity varies with different HPA loadings. The complete conversion of glycerol was obtained, and the selectivity of di- and tri- glycerol ethers was highest (26%) at 110 °C using 40% DTP/BNT catalysts. It is observed that the increase in DTP from 10 to 40% favours an increase in glycerol conversion from 11.52 to 100% with the selectivity of di- and tri-ethers to 26%.

The paper was aimed to isolate a strain of Saccharomyces cerevisiae with higher alcohol, butanol. 32 strains of S. cerevisiae were isolated and identified from the dough starters from different regions. First, sterile flour solution (SFS) was developed as a substrate, and the HS-SPME-GC/MS technique was used to detect the volatile compounds, especially butanol. Then, gas production rate and acid-producing efficacy of S. cerevisiae were detected by Wickerham’s method and pH meter for assessing the ability to metabolize different sugar, respectively. Finally, pulsed-field gel electrophoresis (PFGE) was performed to determine the genetic relationships among the strains. As a result, the SC-X1 obtained the highest concentration of butanol by metabolizing SFS, and the SC-N1 produced the richest variety of flavors during fermentation. The SC-X1 had a better acid-producing ability, it metabolized glucose, sucrose and maltose to produce acid which lower the pH value by 2.26, 2.17 and 1.46, respectively. The SC-X1 had higher gas-producing efficiency by utilizing glucose and sucrose, and the SC-N1 had perfect performance in gas-producing. The PFGE similarity coefficient was high in relationship with the S. cerevisiae resource. Through comprehensive analysis, SC-X1 and SC-N1 were chosen for further research due to their excellent chemical and microbiological performances. Especially, the SC-X1 is very potential for commercial usage with high production of butanol.

Phenolic compounds contribute to the antioxidant property of plants and the efficient extraction of plant phenolics could enhance its antioxidant potential. Lagerstroemia speciosa (L.) Pers. has been investigated for its pharmacological activities, but comparing its antioxidant activities of phenolics derived from its various parts has a key role in developing natural antioxidants. This study was conducted to standardize the extraction of phenolics from leaves, pods and branches of L. speciosa plant, followed by determination of antioxidant activities of their solvent fractions. Phenolic compounds were extracted from the leaves, pods and branches under different parameters such as temperature, pH, type of solvent and volume of the solvent. The extracted phenolic compounds were subjected to solvent fractions and antioxidant assays were performed. Among the various extraction methods tested, the best method was 50% ethanol +1% HCl, refluxing temperature, 100 ml of solvent and 1 hour extraction time. The best solvent fractions were determined as NaHCO3 + ethyl acetate for pods and ethyl acetate alone for leaves and branches with extracted phenolics content of 150.2 mg/g, 136.2 mg/g and 82.9 mg/g, respectively. The chloroform fraction was best among the fractions with maximum ascorbic acid equivalent (ASE) in all the parts of L. speciosa tested. Ferrous ion chelating capacity indicated that butanol fraction had the highest chelation and the same was recorded in ferric ion chelating assay with an EC50 value of 28.2. Hydroxyl radical scavenging activity of the fractions indicated that NaHCO3 + EtOAc fraction of pods had potential activity. Thus, the phenolic compounds from L. speciosa are excellent sources for future investigation on potent natural antioxidant compounds.

1-Butanol is a potential bio-based fermentation product obtained from cellulosic biomass. As a value-added chemical, 2-ethyl-1-hexanol (2-EH) can be produced by Guerbet conversion from 1-butanol. This work reports the enhanced catalytic Guerbet reaction of 1-butanol to 2-EH by a series of Cp*Ir complexes (Cp*: 1,2,3,4,5-pentamethylcyclopenta-1,3-diene) coordinated to bipyridine-type ligands bearing an ortho-hydroxypyridine group with an electron-donating group and a Cl− anion. The catalytic activity of the Cp*Ir complex increased by increasing the electron density of the bipyridine ligand when functionalized with the para-NMe2 and ortho-hydroxypyridine groups. A record turnover number of 14047 was attained. A mechanistic study indicated that the steric effect of the ethyl group on the α-C of 2-ethylhexanal (2-EHA) and the conjugation effect of C=C–C=O in 2-ethylhex-2-enal (2-EEA) benefits the high selectivity of 2-EH from 1-butanol by inhibiting the cross-aldol reaction of 2-EHA and 2-EEA with butyraldehyde. Nuclear magnetic resonance study revealed the formation of a carbonyl group in the bipyridine-type ligand via the reaction of the Cp*Ir complex with KOH.

Clostridium acetobutylicum DSM 792 has been characterized as a native acetone-butanol-ethanol (ABE) fermenting bacterium. C. acetobutylicm is used as a model organism to improve solvent production by metabolic engineering strategies. In this study, the ABE pathway in C. acetobutylicum was modified by overexpressing the pyruvate decarboxylase gene from Zymomonas mobilis under the control of 2 promoters, namely Pferr and Ppta (promoters of genes encoding pyruvate ferredoxin oxidoreductase and phosphotransacetylase) and the recombinant strains were designated as DSM 792(pPDC1) and DSM 792(pPDC2). The specific activity of the alcohol dehydrogenases in the pdc-expressing strains was higher than that in the wild-type strain. In batch fermentation experiments, the total ABE production from the recombinant strains DSM 792 (pPDC1) and DSM 792 (pPDC2) was 1.57 and 7.9 g/L, respectively, which was higher when compared to the wild type ABE production (0.64 g/L) under uncontrolled pH. The alcohol to acetone ratio (BE/A) was found to be 2.28, 2.77, and 5.26 in wild type, DSM 792 (pPDC1), and DSM 792 (pPDC2), respectively. This suggests that the re-routing of pyruvate by overexpression of the pdc could play a role in the generation of more reducing equivalents towards ethanol and butanol production.

Effective diffusion coefficients (De) of acetic acid, butyric acid, and butanol in compacted montmorillonite were determined by through-diffusion experiments and compared with those of iodide and deuterated water. The difference in De values between acetic acid, butyric acid, and iodide could be attributed to the difference in their self-diffusion coefficient values, while this was not applicable to the De values determined for butanol and deuterated water. This result suggests that the De values of iodide can be converted to those of carboxylic acid and utilized for migration analysis of carbon-14 in the safety assessment of geological disposal.

Biobutanol is one of the promising biofuels, which is produced by fermentation. The concentration of butanol in the fermentation broth does not usually reach 2% (by wt). To use biobutanol as fuel, it is necessary to purify this mixture. In this study, chitosan and sodium alginate hybrid membranes filled with zeolitic imidazolate framework-90 (ZIF-90) were synthesized and utilized for butanol dehydration by the pervaporation process. The synthesized pristine and hybrid membranes were characterized by SEM, FTIR, TGA and contact angle. The swelling resistance of the membrane was determined by sorption tests. Hybrid membranes display higher thermal and mechanical stability and swelling resistance compared to pristine membranes. The separation performance of membranes was determined through pervaporation process. The effects of ZIF loading ratio, process temperature and feed concentration on separation performance were investigated. Compared to pristine membranes, hybrid membranes were found to be more effective for dehydration of butanol by pervaporation. Among hybrid membranes, sodium alginate hybrid membranes filled with ZIF-90 displayed the best separation performance. While the highest flux and separation factor values of 0.987 kg/m2h and 1978 were obtained using sodium alginate hybrid membrane, the flux value of 0.325 kg/m2h and the separation factor value of 1124 were achieved in chitosan hybrid membrane.

A solid-liquid extraction and an HPLC method for determination of rebaudioside A from the leave parts of Stevia rebaudiana were developed. Separation method consisted of solvent extraction of leaf powder using various solvents like petroleum ether, methanol, diethyl ether and butanol followed by its purification using high performance liquid chromatography in order to obtain bioactive compound rebaudioside A. This solvent selection is very important prior to alternative extraction methods since it can be used as a pre-extraction solvents, main solvents, or co-solvents. The problem of hydrolysable components and solvent removal difficulties in the conventional extraction led us to study further the effects of solvent properties on the conventional extraction using Soxhlet method in order to determine the best solvent or solvent mixture for high extraction yield of S. rebaudiana. The chromatographic separation was realized using a C18 column, mobile phase consisting of methanol: water with UV detection at 210 nm. Based on the yield of extraction and glycosides content, methanol was found to be best solvent.

In this study, the optimization of the amount of enzyme consumed in the enzymatic phase of substitution of butanol solvent instead of methanol in the powder washing phase after filtration was investigated. To perform this study, different amounts of the enzyme penicillin G amidase (PGA) were tested in reactions with the same conditions. The highest efficiency was observed in the reaction that the ratio of penicillin powder to the amount of enzyme was 2:1. In this reaction, for every 100 g of penicillin consumed, 50 g of the PGA was used. Replacement of butanol instead of methanol after filtration, the powder obtained from this step was washed with butanol instead of methanol and the powder obtained from this step was examined after drying. The resulting solvent powder was very small and the drying speed of the powder increased compared to the time of methanol usage. Optimizing the amount of enzyme in this process due to the high cost of the enzyme made this reaction more economically viable at the end of this study. In this study, for the first time, butanol was used as a suitable substitute for methanol and the ratio of enzyme use to penicillin powder was optimized. This research deals with the future perspective in the field of research in this regard.

Immobilization of microbe cells has been considered as a potential alternative for enhancing biobutanol productivity through acetone-butanol-ethanol (ABE) fermentation. Vetiver grass (VG; Vetiveria zizanoides) pretreated by sodium hydroxide (NaOH) or sulphuric acid was used as carrier for immobilized Clostridium beijerinckii TISTR 1461 in ABE fermentation. The removal of the lignin and hemicellulose fractions of VG during the pretreatment resulted in structural changes, especially an increased crystallinity and surface area. The VG pretreated with 6% (w/v) NaOH at 120 °C for 6 h had the best potential as a carrier in ABE fermentation, giving a butanol and total ABE concentration of 11.6 g/L and 19.8 g/L, respectively, approximately 1.3-fold greater than that of the free-cell system. The VG samples were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and surface area analyses.

Butanol could reduce emissions and alleviate the energy crisis as a bio-fuel used on engines, but the production cost problem limits the application of butanol. During the butanol production, ABE (Acetone-Butanol-Ethanol) is a critical intermediate product. Many studies researched the direct application of ABE on engines instead of butanol to solve the production cost problem of butanol. ABE has the defects of large ignition energy and vaporization heat. Hydrogen is a gaseous fuel with small ignition energy and high flame temperature. In this research, ABE port injection combines with hydrogen direct injection, forming a stratified state of the hydrogen-rich mixture around the spark plug. The engine speed is 1500 rpm, and λ is 1. Five αH2 (hydrogen blending fractions: 0, 5%, 10%, 15%, 20%) and five spark timings (5°, 10°, 15°, 20°, 25° CA BTDC) are studied to observe the effects of them on combustion and emissions of the test engine. The results show that hydrogen addition increases the maximum cylinder pressure and maximum heat release rate, increases the maximum cylinder temperature and IMEP, but the exhaust temperature decreases. The flame development period and flame propagation period shorten after adding hydrogen. Hydrogen addition improves HC and CO emissions but increases NOx emissions. Particle emissions decrease distinctly after hydrogen addition. Hydrogen changes the combustion properties of ABE and improves the test engine's power and emissions. The combustion in the cylinder becomes better with the increase of αH2, but a further increase in αH2 beyond 5% brings minor improvements on combustion.

To meet the increasing requirements toward biobutanol, pervaporation membrane with high separation performance needs to be developed. In this work, a hydrophobic MAF-6 (RHO-[Zn(eim)2]) was synthesized and its adsorption properties for 1-butanol was systematically studied, which are supposed to benefit the separation performance of polydimethylsiloxane (PDMS) membrane. The hydrophobic MAF-6 particles were therefore doped into PDMS to fabricate mixed matrix membrane. The morphology, chemical structure, and other properties of particles and hybrid membrane were fully studied by SEM, PXRD, FT-IR, TGA, and BET. Results demonstrate that the hydrophobicity of PDMS membrane is improved with the water contact angle increasing from 112.7° to 118.1° after being doped with MAF-6, as well as enhanced adsorption ability toward 1-butanol. More importantly, when doping MAF-6 into PDMS layer, the enhancements of 23.30% and 41.93% are separately observed in the separation factor and total flux to separate 1.5 wt% 1-butanol solution, compared with the PDMS membrane. In addition, the heat energy consumption of pervaporation process is decreased from 4.27 to 3.71 kJ g−1 via the doping of MAF-6. Overall, this work confirms that the hydrophobic particle such as MAF-6 is not only conductive to enhance the separation performance of PDMS membrane but also helpful to decrease the energy consumption.

Background: The phytochemical screening and antidiabetic activities of the methanol leaf extract and fractions of Sansevieria liberica Ger. and Labr. were investigated.Objectives: To identify the phytoconstituents present and evaluate the anti-diabetic activity of the leaf of S. liberica Ger. and Labr.Material and Methods: A 1.2 g of the pulverized leaf was cold macerated in methanol to obtain 240 g of the crude extract (CE), fractionation was done using n-hexane, ethylacetate and butanol. The CE and the fractions were screened for phytochemical and antidiabetic analysis using standard procedures. Diabetes was induced by intraperitonial injection of alloxan. The blood glucose levels were analyzed as indices of diabetes.Results: After 24 hours, alloxan increased the blood glucose level of rats indicating hyperglycaemia. Treatment of the rats with the extract and fractions reduced the blood glucose level within 3 to 7 days of treatment. The standard antidiabetic, metformin (500 mg/kg) also showed similar effect. Extracts (250 and 500 mg/kg) of the crude extract decreased significantly (p n-Hexane fraction > butanol fraction. The phytochemical screening of the extract and fractions revealed the presence of flavonoids, steroids, alkaloids, glycosides etc.Conclusions: From the findings, S. liberica leaf posses antidiabetic activity which may be due to the phytochemical constituents present, and this justifies its use by local users as traditional remedy for diabetes mellitus.

Cu/TiO2 was modified by adding Rh as co-catalyst and used as a highly efficient photocatalyst for the hydrogen evolution reaction. A low amount of Rh was loaded onto Cu/TiO2 by the deposition-precipitation with urea (DPU) method to observe the effect on the hydrogen production displayed by different samples. The Rh–Cu/TiO2 oxide structure exhibited a remarkably high photocatalytic hydrogen evolution performance, which was about twofold higher than that of the Cu/TiO2 monometallic photocatalyst. This outstanding performance was due to the efficient charge carrier transfer as well as to the delayed electron-hole recombination rate caused by the addition of Rh. The influence of the different parameters of the photocatalyst synthesis and reaction conditions on the photocatalytic activity was investigated in detail. Hydrogen evolution was studied using methanol, ethanol, 2-propanol and butanol as scavengers with an alcohol:water ratio of 20:80. The methanol-water system, which showed the highest hydrogen production, was studied under 254, 365 and 450 nm irradiation; Rh–Cu/TiO2 showed high photocatalytic activity with H2 production rates of 9260, 5500, and 1940 μmol h−1 g−1, respectively. The Cu–Rh/TiO2 photocatalyst was active under visible light irritation due to its strong light absorption in the visible region, low band gap value and ability to reduce the electron (e−) and hole (h+) recombination.

The influence of acid-base properties of MgO-Al2O3 systems obtained by the decomposition of hydrotalcites with ratio of Mg/Al = 1÷3 on their activity and selectivity in the process of ethanol conversion to 1-butanol is studied.The highest values of selectivity and specific rate of BuOH formation are achieved with ratio Mg/Al = 2 for the sample, which according to the test results is characterized by the largest number of acid and basic sites in the dehydrogenation/dehydration reactions of isopropanol.

Objectives Human immunodeficiency virus (HIV) infection is considered as a major immunosuppressive disease linked to malignancies and other opportunistic infections. Recently, the high prevalence of HIV drug-resistant strains required a high demand for novel antiviral drug development, especially in herbal medicine approaches. The objective of this study was to evaluate the possibility of Ficus fistulosa leaves can inhibit HIV replication in ethanol extract form as well as its fractions using chloroform, ethyl acetate, and butanol solvents. Methods F. fistulosa leaves were extracted using ethanol as a solvent and further gradually fractionated in chloroform, ethyl acetate, and butanol solvents. The targeted persistently infected virus (MT4/HIV) cell lines were cocultured with ethanol extract and fractions at different time points. The syncytium formation and cytotoxicity assays were performed to evaluate the potential antiviral activity of F. fistulosa leaves. Results One of the four tested extract/fractions showed antiviral activity against HIV. The ethanol extract showed weak inhibition with a high level of toxicity (IC50 = 8.96 μg/mL, CC50 ≥50 μg/mL, and SI = 5.58). Meanwhile, chloroform fraction effectively inhibited the MT4/HIV cell proliferation while keeping the toxicity to a minimal level (IC50 = 3.27 μg/mL, CC50 = 29.30 μg/mL, and SI = 8.96). In contrast of ethyl acetate fraction and butanol fraction showed no anti HIV activity with a high level of toxicity (CC50 ≥50 μg/mL) and low SI value (>2.17 μg/mL and >0.97 μg/mL). Conclusions Chloroform fraction of F. fistulosa leaves showed effectively as anti-viral activity against MT4/HIV cells.

Abundant alcohols, including ethanol, propanol, butanol, and pentanol, are expected to be used in compression ignition engines to ease the shortages of fossil fuel. The various alcohols have quite a different combustion and emission characteristics in the engine due to the changes in molecular structures. In this paper, a series of experiments were conducted on a modified common-rail diesel engine fueled with diesel/alcohols blended fuels in a wide operating range. The effects of alcohol chain length, oxygen content, and molecular structure on engine combustion and emission characteristics are studied systematically. The experimental results show that the blending of alcohols increases the peak values of in-cylinder pressure and maximum pressure rising rate. Besides, the combustion duration and ignition delay are mainly affected by oxygen content and isomer structure. The addition of short-chain alcohols will significantly reduce the total mass of particulate matter (PM) emissions, while the CO and HC emissions increase appropriately. The CO, HC, aldehydes, and ethylene emissions are mainly affected by carbon chain length and isomer structure. For PM emissions, the carbon chain length, molecular structure, and oxygen content of alcohol fuels have different influences on PM number, PM mass, and particle size distributions. The shorter carbon chain of alcohol leads to smaller particle size, and higher oxygen content leads to lower total particle mass.

The influence of replacing water with ethanol, propanol, and butanol in alcohol–water mixtures on the rheological properties of wormlike micelles (WLMs) consisting of sodium salicylate (NaSal) and cetyltrimethylammonium bromide (CTAB) is investigated at 25 °C. At maximum viscosity of 100 mM CTAB and 60 mM NaSal, the alcohols at low concentrations of up to 8% ethanol, 3% propanol, and 2% butanol do not affect the WLM structure as indicated by the normal modulus values of the solutions, but they decrease the structural relaxation times and their viscosities. This behavior is explained by the fact that as alcohol chain length increases, it has lower miscibility in water, and hence, it can interact to a higher extent with WLMs even at lower contents. We hypothesize that alcohols adsorbed at the WLM surface make it more hydrophilic. The contacts between WLMs are therefore lost, the viscosity decreases, and the structural relaxation times become faster. At suitable contents, alcohol molecules can penetrate WLMs and damage their structure. For solutions with minimum viscosity, higher alcohol contents were required to destroy WLMs, and replacing water with ethanol leads to viscosity increase, followed by a gradual decrease at higher ethanol contents. Propanol and butanol drastically changed the WLM viscoelastic properties. Generally, as the alcohol chain length increases, WLMs become more pronounced at lower alcohol contents. Alcohols, at relatively low amounts, do not affect the WLM structure but lead to vanishing of the entanglement between WLMs. Butanol, due to its longer chain compared to ethanol and propanol, destroys WLMs at lower contents. Generally, as alcohol chain length increases, the damage of entanglement between WLMs becomes more pronounced at lower alcohol contents.

The plants Astragalus pterocephalus growing in Uzbekistan are a source of triterpene glycosides. The main triterpene glycoside, in terms of content, is a cycloartan glycoside – cyclosiversioside F. To obtain an individual biologically active compound cyclosiversioside F with 95% purity, a proposed method involves extraction with methanol, concentration and dilution with an equal volume of water, then followed by a sequential extraction from the aqueous extract with chloroform, ethyl acetate and butanol. Then a chromatographic separation of the purified amount of extractives on a column with silica gel, isolation of the substance and precipitation from a solvent system must be performed, followed by recrystallization and drying. The optimal conditions for the isolation and separation of the amount of extractive substances have been developed in order to obtain an individual glycoside. Cyclosiversioside F was authenticated by TLC in comparison with an authentic sample. Quantitative analysis of the glycoside was carried out by HPLC. The purity of cyclosiversioside F was confirmed by taking 1H and 13C NMR spectra., Растение Astragalus pterocephalus Bunge, произрастающее в Узбекистане, является источником тритерпеновых гликозидов. Основным гликозидом циклоартанового ряда по содержанию является циклосиверсиозид F. Разработаны оптимальные условия выделения и разделения суммы экстрактивных веществ с целью получения индивидуального гликозида. Для получения индивидуального биологически активного соединения с 95% чистотой предложена методика экстракции метанолом, концентрирование и разбавление равным объемом воды. Затем последовательное извлечение из водного экстракта хлороформом, этилацетатом и бутанолом. Далее – хроматографическое разделение очищенной суммы экстрактивных веществ на колонке с силикагелем, выделение субстанции и осаждение из системы растворителей с последующей перекристаллизацией и сушкой. Установлена подлинность исследуемого соединения с помощью ТСХ в сравнении с аутентичным образцом. Чистоту циклосиверсиозида F подтвердили снятием спектров ЯМР 1Н и 13С. Методом ВЭЖХ проведен количественный анализ гликозида.

The article presents the results of computer modeling and experimental research of the effect of butanol content in the fuel on the specific power, fuel-economic and environmental performance of 4ЧН 11/12.5 (4ChN 11/12.5) diesel engine at various cycle fuel supplies and exhaust gas recirculation rates. The research has been carried out at crankshaft speeds of 1,000, 1,200, 1,400, 1,600, 1,800, 2,000 and 2,200 rpm with 25, 50, 75 and 100 % load. Fuels with butanol content of 5, 10, 15, 20, 25, and 30 % by volume have been investigated. The computer model of the diesel working process has been developed that takes into account the physical and chemical properties of the fuel, the characteristics of the fuel flow in the nozzle tip and the development of fuel sprays in the combustion chamber. Based on the results of computer modeling, dependencies have been determined that make it possible to assess the effect of the percentage of butanol in mixed fuel on the mean indicator pressure, specific fuel consumption, indicator efficiency, emissions of nitrogen oxides and dynamic indicators of the combustion process when choosing the composition of mixed butanol-containing fuel. Based on the conducted research, the following composition of mixed fuel has been selected: 85 % diesel fuel and 15 % butanol. Comparative tests of the diesel engine have been carried out when working on the external speed characteristic on diesel fuel and its mixture with 15 % butanol. It is obtained that when using mixed fuel, the character of the power change remains unchanged, the exhaust smoke decreases, nitrogen oxides emissions decrease at crankshaft speeds of 1,400, 1,600, 1,800, and 2,200 rpm, and the effective engine efficiency remains practically unchanged.