Breeding of Ferment Bacteria and Control of Methanol and Higher Alcohols in Jujube Wine

Jujube wine is a health drink with local characteristics and is worth pro- moting. Jujube wine fermentation can be divided into alcoholic fermentation and mal- olactic fermentation. Yeast is the key of alcoholic fermentation while lactic acid bac- teria is the key of malolactic fermentation, and therefore the breeding of yeast and lactic acid bacteria is crucial for the quality of jujube wine. Besides, the control of methanol is a major problem in production, and the control of higher alcohol is also difficult. Thus, we summarized the research related with the breeding of yeast and lactic acid bacteria, and the control of methanol and higher alcohols, and proposed that breeding specialized yeast and lactic acid bacteria was the future research di- rection. Moreover, the production mechanism of methanol and higher alcohols was investigated, and the content of methanol and higher alcohols was effectively con- trolled on the basis of quality guarantee, providing references for the production technology of jujube wine.

Effect of Surfactant-lnduced Modifications on CuCoMn Catalysts for Higher Alcohol Synthesis

A series of surfactant-modified CuCoMn-based catalysts were prepared for higher alco- hol synthesis from biomass-based syngas. Three typical surfactants, cetyltrimethylammonium bromide （CTAB）, sodium dodecyl sulfate （SDS） and pluronic P123 triblock copolymer （EO20PO70EO20）, were employed. Compared to surfactant-free CuCoMn catalyst, CO conversion increased from 17.4% to 29.7% over SDS-modified CuCoMn catalyst, and the selectivity of higher alcohols increased from 22.0% to 41.2% over CTAB-modified catalyst. Besides, the proportions of higher alcohols in total alcohols increased over all surfactantmodified catalysts. The catalysts were characterized by N2 adsorption/desorption, XRD, XPS and IR analysis. The results showed that several more favorable features rendered the CTAB-modified CuCoMn catalyst to be suitable for higher alcohol production, such as the larger pore size, better crystallinity of CuCoMnO4 spinel. moderate surface atomic distribution and lower valence of metallic ions. In addition, it was verified that CTAB addition at the metal precipitation stage was beneficial to higher alcohol synthesis. Surfactant-induced modification provides a promising alternative method for catalyst improvement in synthesis of higher alcohols.

Higher alcohol synthesis over Cu-Fe composite oxides with high selectivity to C_(2+)OH

Cu-Fe composite oxides were prepared by co-precipitation method and tested for higher alcohol synthesis from syngas. The selectivity to C2＋OH and C6＋OH in alcohol distribution was very high while the methane product fraction in hydrocarbon distribution was rather low, demonstrating a promising potential in higher alcohols synthesis from syngas. The distribution of alcohols and hydrocarbons approximately obeyed Anderson-Schulz-Flory distribution with similar chain growth probability, indicating alcohols and hydrocarbons derived from the same intermediates. The effects of Cu/Fe molar ratio, reaction temperature and gas hourly space velocity （GHSV） on catalytic performance were studied in detail. The sample with a Cu/Fe molar ratio of 10/1 exhibited the best catalytic performance. Higher reaction temperature accelerated water-gas-shift reaction and led to lower total alcohols selectivity. GHSV showed great effect on catalytic performance and higher GHSV increased the total alcohol selectivity, indicating there existed visible dehydration reaction of alcohol into hydrocarbon.

Synthesis of Higher Alcohols from Syngas over Alkali Promoted K-Co-Mo Catalysts Supported on Multi-walled Carbon Nanotubes

A series of carbon nanotubes-supported K-Co-Mo catalysts were prepared by a sol-gel method combined with incipient wetness impregnation. The catalyst structures were characterized by X-ray diffraction, N2 adsorption-desorption, transmission electron microscopy and H2-TPD, and its catalytic performance toward the synthesis of higher alcohols from syngas was investigated. The as-prepared catalyst particles had a low crystallization degree and high dispersion on the outer and inner surface of CNTs. The uniform mesoporous structure of CNTs increased the diffusion rate of reactants and products, thus promoting the reaction conversion. Furthermore, the incorporation of CNTs support led to a high capability of hydrogen absorption and spillover and promoted the formation of alkyl group, which served as the key intermediate for the alcohol formation and carbon chain growth. Benefiting from these characteristics, the CNTs supported Mo-based catalyst showed the excellent catalytic performance for the higher alcohols synthesis as compared to the unsupported catalyst and activated carbon supported catalyst.

Cu-Co bi-metal catalyst prepared by perovskite CuO/LaCoO_3 used for higher alcohol synthesis from syngas

Cu-Co bi-metal catalysts derived from CuO/LaCoO3 perovskite structure were prepared by one-step citrate complexing method, and the structure evolution reaction from CuO/LaCoO3 to Cu-Co2C/La202CO3 under 1-12 pretreatment was investigated by techniques of XRD, TPR and TEM. The results suggest that a much higher dispersion of copper significantly enhanced the reduction of cobalt, and a stronger interaction between copper and cobalt ions in LaCoO3 particles led to the formation of bi-metallic Cu-Co particles in the reduced catalysts and the enrichment of Co on the surface of bimetallic particles. The prepared catalysts were highly active and selective for the alcohol synthesis from syngas due to the presence of copper-modified C02C species.

Effects of Activation Atmospheres on Structure and Activity of Mo-based Catalyst for Synthesis of Higher Alcohols

Activated carbon supported Mo-based catalysts were prepared and reduced under different activation atmospheres, including pure H2, syngas （H2/CO=2/1）, and pure CO. The cat- alysts structures were characterized by X-ray diffraction , X-ray absorption fine structure, and in situ diffuse reflectance infrared Fourier transform spectroscopy. The catalytic per- formance for the higher alcohol synthesis from syngas was tested. The pure H2 treatment showed a high reduction capacity. The presence of a large amount of metallic CoO and low valence state Mo^φ＋ （0〈φ〈2） on the surface suggested a super activity for the CO dissoci- ation and hydrogenation, which promoted hydrocarbons formation and reduced the alcohol selectivity. In contrast, the pure CO-reduced catalyst had a low reduction degree. The Mo and Co species at the catalyst mainly existed in the form of Mo^4＋ and Co^2＋. The syngas- reduced catalyst showed the highest activity and selectivity for the higher alcohols synthesis. We suggest that the syngas treatment had an appropriate reduction capacity that is between those of pure H2 and pure CO and led to the coexistence of multivalent Co species as well as the enrichment of Mo~＋ on the catalyst＇s surface. The synergistic effects between these active species provided a better cooperativity and equilibrium between the CO dissociation, hydrogenation and CO insertion and thus contributed beneficially to the formation of higher alcohols.

Conversion of syngas to higher alcohols over Cu-Fe-Zr catalysts induced by ethanol

Ethanol induced method was applied to prepare Cu-Fe-Zr catalysts for conversion of syngas to higher alcohols. The catalytic performance of the catalysts induced by ethanol was superior to that of the catalyst prepared by the conventional precipitation method. Among various procedures for ethanol induced method, it was found that incorporation of ethanol in the precipitation process was the better. After incorporation of ethanol, the crystal size of CuO decreased and the reduction of copper species became easier. The better activity of Cu-Fe-Zr catalysts prepared by ethanol induced procedures was probably caused by the higher dispersion of Cu species.

Electron promoted ZnO for catalytic synthesis of higher alcohols from syngas

Direct conversion of syngas from those non-petroleum carbon resources to higher alcohols are very attractive due to the process simplicity with low energy consumption.However,the reaction always suffers from low yield as well as low selectivity.Herein,effective increase of higher alcohols proportion in the product is realized by direct conversion of syngas over electronically-modulated ZnO semiconductor via Cu doping.It is considered that the lower Fermi level and narrower band gap of catalysts by embedding Cu^(2+)into ZnO lattice could facilitate donor reaction by boosting the process for the reactants to obtain electrons on the catalyst surface for the formation of CH_(x) species and carbon chain growth,in which the Cu doping on ZnO lattice play important role in the promotion of CO adsorption.As a result,4 mol%Cu doped ZnO exhibits a highest C_(2+) OH/ROH fraction of 48.1%.Selectivity of catalysts from straight chain alcohol is better than from branch chain alcohol,which is different from promoted Cu/ZnO based catalyst.However,over-doping of Cu(7 mol%)on ZnO results in the aggregation Cu species on ZnO surface,leading to a sharp decrease of higher alcohols proportion to 3.2%.The results shed light on the nature that a direct correlation between semiconductor Fermi level and synthesis of higher alcohols,and the semiconductor-based catalysts mainly accelerate the hydrogenation reactions by enhancing thermally excited electron transfer.

On the role of cobalt carbidization in higher alcohol synthesis over hydrotalcite-based Co-Cu catalysts

Co-Cu-based catalysts are widely applied in higher alcohol synthesis (HAS) from synthesis gas. Although the nature of the active sites is still not fully understood, the formation of Co2C under HAS conditions seems to play a major role. A CO pretreatment procedure was developed allowing a systematic investigation of the influence of cobalt carbidization on the structural properties and catalytic performance of the catalysts. By exposing the catalyst to a CO-containing atmosphere prior to HAS, Co enrichment of the catalyst surface occurred followed by carbide formation. This surface modification decreased the formation of hydrocarbons and enhanced the formation of C2+OH. The catalyst pretreated with CO at 20 bar achieved the highest selectivity to ethanol and the lowest hydrocarbon selectivity.

Bifunctionality of Cu/ZnO catalysts for alcohol-assisted low-temperature methanol synthesis from syngas:Effect of copper content

Alcohol-assisted low-temperature methanol synthesis was conducted over Cu/ZnO;catalysts while varying the copper content（X）. Unlike conventional methanol synthesis, ethanol acted as both solvent and reaction intermediate in this reaction, creating a different reaction pathway. The formation of crystalline phases and characteristic morphology of the co-precipitated precursors during the co-precipitation step were important factors in obtaining an efficient Cu/ZnO catalyst with a high dispersion of metallic copper,which is one of the main active sites for methanol synthesis. The acidic properties of the Cu/ZnO catalyst were also revealed as important factors, since alcohol esterification is considered the rate-limiting step in alcohol-assisted low-temperature methanol synthesis. As a consequence, bifunctionality of the Cu/ZnO catalyst such as metallic copper and acidic properties was required for this reaction. In this respect, the copper content（X） strongly affected the catalytic activity of the Cu/ZnO;catalysts, and accordingly, the Cu/ZnO;.5 catalyst with a high copper dispersion and sufficient acid sites exhibited the best catalytic performance in this reaction.

MoP with rich species generated via radio frequency thermal plasma for higher alcohols synthesis from syngas

In this paper, the molybdenum phosphide(MoP) catalysts(TPR-MoP and TPR-MoP-Pla) were prepared by the traditional method and the RF(radio frequency) thermal plasma technique respectively and characterized by x-ray diffraction(XRD), x-ray photoelectron spectroscopy(XPS), transmission electron microscope(TEM), hydrogen temperature-programmed desorption(H_2-TPD) and carbon monoxide temperature-programmed desorption(CO-TPD) measurements,and their catalytic performance for HAS was evaluated. The results showed that the total and C_(2+) alcohols selectivity of the catalyst after plasma treatment(TPR-MoP-Pla) were enhanced.The enhanced catalytic performance could be related to more dislocation defects and the synergistic effect between Mo^(0–2+) and Mo^(4+) valence species in the TPR-MoP-Pla catalyst. In addition, this work suggests that thermal plasma treatment can be used as a new preparation technique for the synthesis of materials with rich species.

Nanosheet-structured K–Co–MoS_2 catalyst for the higher alcohol synthesis from syngas: Synthesis and activation

The nanosheets structured K–Co–MoS_2 catalyst was prepared through a one-step hydrothermal synthesis combined with the wetness impregnation. The fresh catalyst has a high dispersion of Co–Mo–S active phase and no Co_9S_8 is found. The pure H_2 activated catalyst shows a higher intrinsic activity, especially the C_(2+) OH selectivity for the higher alcohol synthesis compared to the one activated by 5% H_2/N_2 atmosphere. The reason is attributed to that the pure H_2 activation more effectively suppresses the formation of Co_9S_8 and stabilizes the Co–Mo–S active phase during the reaction due to the formation of SH species.

Using Raman Spectroscopy for Determination Methanol Quantity in Illegal Alcoholic Beverages

Illegal production of alcoholic beverages is a common problem in most countries.The consumption of these counterfeit alcoholic products in Turkey has increasingly been one of the major health concerns.In this study,a comparison between GC-MS and Raman spectroscopy techniques was made to determine the amount of methanol in BogmaRaki which is a counterfeit alcoholic beverage produced and consumed in Hatay region.Different ratios of methanol/ethanol concentrations were prepared to obtain a calibration curve.This curve was used to measure the amount of methanol in the actual product samples using both GC-MS and Raman spectroscopy techniques.Results obtained from both techniques were compared using Paired sample t-tests.The Limit of Detection and the Limit of Quantification values were determined as 0.03(%v/v) and 0.11(%v/v),respectively.Both techniques demonstrated a similar sensitivity in the determination of methanol concentration in these counterfeit products(p>0.05).Raman Spectroscopy,however,has an advantage of being easy to use,inexpensive,rapid and non-destructive analytical technique with little or no sample preparation.

Mortality-related electrocardiogram indices in methanol toxicity

Iran experienced one of the largest methanol poisoning outbreaks shortly after the coronavirus pandemic due to misinformation about the beneficial effects of alcohol in preventing and treating this viral infection.^([1])According to the Iran Legal Medicine Organization(LMO),over 3,100 methanol toxicity cases and 728 deaths were reported across the country,resulting in a syndemic of methanol poisoning.^([2])There is very little literature on the electrographic predictors of cardiovascular mortality in methanol poisoned patients.^([3])

Outbreak of methanol-induced optic neuropathy in early COVID-19 era;effectiveness of erythropoietin and methylprednisolone therapy

BACKGROUND Methanol is a highly toxic,non-potable alcohol.Outbreaks of methanol toxicity occur due to its fraudulent addition to alcoholic beverages as a cheaper substitute for ethanol.Recently,alongside the coronavirus disease 2019(COVID-19)pandemic,rumors circulated on social media that consuming alcohol can prevent or cure the virus,leading to a COVID-19 and methanol-induced optic neuropathy(MON)syndemic.AIM To investigate the impact of erythropoietin(EPO)on the outcomes of patients diagnosed with MON.METHODS In this prospective study,105 patients presenting with acute bilateral visual loss secondary to methanol intoxication were enrolled from March to May 2020 at Farabi Eye Hospital.A comprehensive ocular examination was conducted for all participants.Recombinant human EPO and methylprednisolone were administered intravenously to all patients for three consecutive days.RESULTS The mean age of the participants was 39.9 years(±12.6).Ninety-four patients were male and eleven were female.The mean pre-treatment best corrected visual acuity(BCVA)improved from 2.0±0.86 to 1.39±0.69 logarithm of the minimum angle of resolution post-treatment(P<0.001),with significant improvement observed in all age categories and genders(P<0.001).Visual acuity improvement was also significant regardless of whether the patient presented before or after 72 h(P<0.001),and the post-treatment BCVA remained significant at all monthly follow-up visits(P<0.001).CONCLUSION EPO and methylprednisolone therapy have been shown to be effective in improving visual outcomes in patients with MON when administrated within the first month of exposure.Public awareness efforts are necessary to prevent further outbreaks of methanol toxicity in the current COVID-19 era.

Application of solid-phase extraction and gas chromatography-mass spectrometry (SPE-GC-MS) in resolution of metabolism pattern of higher alcohols in rat plasma

Higher alcohols are key factors affecting sensory quality and post-drinking comfort of alcoholic beverages. A strategy combining solid-phase extraction and gas chromatography-mass spectrometry(SPE-GC-MS) was established to analyze the metabolism pattern of higher alcohols in rat plasma after gavage of 4 common alcoholic beverages including huangjiu, baijiu, wine and brandy. 7 mL of dichloromethane was determined as the optimal extraction condition, and 8 higher alcohols were precisely quantified with detection limits of 1.82-11.65 μg/L, recoveries of 89.07%-110.89% and fine repeatability. The fastest absorption and elimination rates of plasma total higher alcohols were observed in baijiu and huangjiu group, respectively, and the highest peak concentration was found in brandy group. Additionally, the metabolic rate of plasma isoamyl alcohol in huangjiu group was faster than that in wine group at the same intragastric administration dosage. This study may provide potential insight for evaluation of alcoholic beverage quality.

Highly efficient and stable electrooxidation of methanol and ethanol on 3D Pt catalyst by thermal decomposition of In2O3 nanoshells

In this paper In2O3nanoshells have been synthesized via a facile hydrothermal approach. The nanoshells can be completely cracked into pony-size nanocubes by annealing, which are then used as a support of Pt catalyst for methanol and ethanol electrocatalytic oxidation. The prepared In2O3and supported Pt catalysts (Pt/In2O3) were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), field effect scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry and electrochemical impedance spectroscopy (EIS) were carried out, indicating the excellent catalytic performance for alcohol electrooxidation can be achieved on Pt/In2O3nanocatalysts due to the multiple active sites, high conductivity and a mass of microchannels and micropores for reactant diffusions arising from 3D frame structures compared with that on the Pt/C catalysts. © 2016 Science Press

Synthesis of tetrahedrally coordinated CoO for higher alcohol synthesis directly from syngas

Higher alcohol synthesis directly from syngas is highly desirable as one of the efficient non-petroleum energy conversion routes.Co^(0)–CoO catalysts showed great potential for this reaction,but the alcohol selectivity still needs to be improved and the crystal structure effect of Co^(0)on catalytic behaviors lacks investigation.Here,a series of tetrahedrally coordinated Co^(0)polymorphs were prepared by a thermal decomposition method,which consisted of wurtzite CoO and zinc blende CoO with varied contents.After diluting with SiO_(2),the catalyst showed excellent performance for higher alcohol synthesis with ROH selectivity of 45.8%and higher alcohol distribution of 84.1 wt%under the CO conversion of 38.0%.With increasing the content of wurtzite CoO,the Co^(0)/Co^(2+)ratio gradually increased in the spent catalysts,while the proportion of highly active hexagonal close packed cobalt in Co^(0)decreased,leading to first decreased then increased CO conversion.Moreover,the higher content of zinc blende CoO in fresh catalyst facilitated the retention of more Co^(2+)sites in spent catalysts,promoting the ROH selectivity but slightly decreasing the distribution of higher alcohols.The catalyst with 40%wurtzite CoO obtained the optimal performance with a space time yield toward higher alcohols of 7.9 mmol·gcat^(-1)·h^(-1).

Using transcriptomics to reveal the molecular mechanism of higher alcohol metabolism in Saccharomyces cerevisiae

High alcohols are important flavor compounds in alcoholic beverages,but high concentration of high alcohols is harmful to human health.Higher alcohol synthesis pathways in brewing microorganisms have been investigated,but the interactions between key genes remain to be explored,especially in industrial strains of Saccharomyces cerevisiae.The PDC1 gene was considered to be the main encoding gene ofα-keto acid decarboxylase,and its deletion resulted in a 92.23%increase in isobutanol production and a 14.89%decrease in isoamyl alcohol production.Transcriptome sequencing was used to explore the effects of PDC1 gene deletion on global gene transcription levels,and deletion strategies were utilized to verify the effects of differential genes on higher alcohol production.Deletion of differential gene HMLALPHA2 increased isobutanol production by 26.23%,and decreased isoamyl alcohol and 2-phenylethanol production by 30.31%and 22.35%,respectively.The THI2,THI4,THI20 genes were proved to be related to n-propanol synthesis.In addition,HMRA2 and SIR3 genes were found to influence isoamyl alcohol synthesis pathways,and their deletion increased isoamyl alcohol production by 25.18%and 21.76%.Our discovery of new target genes is useful for elucidating the molecular mechanisms of higher alcohols and the construction of novel low-producing higher alcohol strains.