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Co-expression of TAL1 and ADH1 in recombinant xylose-fermenting Saccharomyces cerevisiae improves ethanol production from lignocellulosic hydrolysates in the presence of furfural

Hasunuma T, Ismail KSK, Nambu Y, Kondo A

J Biosci Bioeng, 2014 Feb;117(2):165-169.
PMID: 23916856 DOI: 10.1016/j.jbiosc.2013.07.007

Lignocellulosic biomass dedicated to bioethanol production usually contains pentoses and inhibitory compounds such as furfural that are not well tolerated by Saccharomyces cerevisiae. Thus, S. cerevisiae strains with the capability of utilizing both glucose and xylose in the presence of inhibitors such as furfural are very important in industrial ethanol production. Under the synergistic conditions of transaldolase (TAL) and alcohol dehydrogenase (ADH) overexpression, S. cerevisiae MT8-1X/TAL-ADH was able to produce 1.3-fold and 2.3-fold more ethanol in the presence of 70 mM furfural than a TAL-expressing strain and a control strain, respectively. We also tested the strains' ability by mimicking industrial ethanol production from hemicellulosic hydrolysate containing fermentation inhibitors, and ethanol production was further improved by 16% when using MT8-1X/TAL-ADH compared to the control strain. Transcript analysis further revealed that besides the pentose phosphate pathway genes TKL1 and TAL1, ADH7 was also upregulated in response to furfural stress, which resulted in higher ethanol production compared to the TAL-expressing strain. The improved capability of our modified strain was based on its capacity to more quickly reduce furfural in situ resulting in higher ethanol production. The co-expression of TAL/ADH genes is one crucial strategy to fully utilize undetoxified lignocellulosic hydrolysate, leading to cost-competitive ethanol production.

Matched MeSH terms: Ethanol/analysis; Ethanol/isolation & purification; Ethanol/metabolism*
Improvement of the butanol production selectivity and butanol to acetone ratio (B:A) by addition of electron carriers in the batch culture of a new local isolate of Clostridium acetobutylicum YM1

Nasser Al-Shorgani NK, Kalil MS, Wan Yusoff WM, Shukor H, Hamid AA

Anaerobe, 2015 Dec;36:65-72.
PMID: 26439644 DOI: 10.1016/j.anaerobe.2015.09.008

Improvement in the butanol production selectivity or enhanced butanol:acetone ratio (B:A) is desirable in acetone-butanol-ethanol (ABE) fermentation by Clostridium strains. In this study, artificial electron carriers were added to the fermentation medium of a new isolate of Clostridium acetobutylicum YM1 in order to improve the butanol yield and B:A ratio. The results revealed that medium supplementation with electron carriers changed the metabolism flux of electron and carbon in ABE fermentation by YM1. A decrease in acetone production, which subsequently improved the B:A ratio, was observed. Further improvement in the butanol production and B:A ratios were obtained when the fermentation medium was supplemented with butyric acid. The maximum butanol production (18.20 ± 1.38 g/L) was gained when a combination of methyl red and butyric acid was added. Although the addition of benzyl viologen (0.1 mM) and butyric acid resulted in high a B:A ratio of 16:1 (800% increment compared with the conventional 2:1 ratio), the addition of benzyl viologen to the culture after 4 h resulted in the production of 18.05 g/L butanol. Manipulating the metabolic flux to butanol through the addition of electron carriers could become an alternative strategy to achieve higher butanol productivity and improve the B:A ratio.

Matched MeSH terms: Ethanol
Effects of changes in chemical and structural characteristic of ammonia fibre expansion (AFEX) pretreated oil palm empty fruit bunch fibre on enzymatic saccharification and fermentability for biohydrogen

Abdul PM, Jahim JM, Harun S, Markom M, Lutpi NA, Hassan O, et al.

Bioresour Technol, 2016 Jul;211:200-8.
PMID: 27017130 DOI: 10.1016/j.biortech.2016.02.135

Oil palm empty fruit bunch (OPEFB) fibre is widely available in Southeast Asian countries and found to have 60% (w/w) sugar components. OPEFB was pretreated using the ammonia fibre expansion (AFEX) method and characterised physically by the Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The results show that there were significant structural changes in OPEFB after the pretreatment step, and the sugar yield after enzymatic hydrolysis using a cocktail of Cellic Ctec2® and Cellic Htec2® increased from 0.15gg(-1) of OPEFB in the raw untreated OPEFB sample to 0.53gg(-1) of OPEFB in AFEX-pretreated OPEFB (i.e. almost a fourfold increase in sugar conversion), which enhances the economic value of OPEFB. A biohydrogen fermentability test of this hydrolysate was carried out using a locally isolated bacterium, Enterobacter sp. KBH6958. The biohydrogen yield after 72h of fermentation was 1.68mol H2 per mol sugar. Butyrate, ethanol, and acetate were the major metabolites.

Matched MeSH terms: Ethanol
Fulltext Effects of glucose, ethanol and acetic acid on regulation of ADH2 gene from Lachancea fermentati

Yaacob N, Mohamad Ali MS, Salleh AB, Abdul Rahman NA

PeerJ, 2016;4:e1751.
PMID: 26989608 DOI: 10.7717/peerj.1751

Background. Not all yeast alcohol dehydrogenase 2 (ADH2) are repressed by glucose, as reported in Saccharomyces cerevisiae. Pichia stipitis ADH2 is regulated by oxygen instead of glucose, whereas Kluyveromyces marxianus ADH2 is regulated by neither glucose nor ethanol. For this reason, ADH2 regulation of yeasts may be species dependent, leading to a different type of expression and fermentation efficiency. Lachancea fermentati is a highly efficient ethanol producer, fast-growing cells and adapted to fermentation-related stresses such as ethanol and organic acid, but the metabolic information regarding the regulation of glucose and ethanol production is still lacking. Methods. Our investigation started with the stimulation of ADH2 activity from S. cerevisiae and L. fermentati by glucose and ethanol induction in a glucose-repressed medium. The study also embarked on the retrospective analysis of ADH2 genomic and protein level through direct sequencing and sites identification. Based on the sequence generated, we demonstrated ADH2 gene expression highlighting the conserved NAD(P)-binding domain in the context of glucose fermentation and ethanol production. Results. An increase of ADH2 activity was observed in starved L. fermentati (LfeADH2) and S. cerevisiae (SceADH2) in response to 2% (w/v) glucose induction. These suggest that in the presence of glucose, ADH2 activity was activated instead of being repressed. An induction of 0.5% (v/v) ethanol also increased LfeADH2 activity, promoting ethanol resistance, whereas accumulating acetic acid at a later stage of fermentation stimulated ADH2 activity and enhanced glucose consumption rates. The lack in upper stream activating sequence (UAS) and TATA elements hindered the possibility of Adr1 binding to LfeADH2. Transcription factors such as SP1 and RAP1 observed in LfeADH2 sequence have been implicated in the regulation of many genes including ADH2. In glucose fermentation, L. fermentati exhibited a bell-shaped ADH2 expression, showing the highest expression when glucose was depleted and ethanol-acetic acid was increased. Meanwhile, S. cerevisiae showed a constitutive ADH2 expression throughout the fermentation process. Discussion. ADH2 expression in L. fermentati may be subjected to changes in the presence of non-fermentative carbon source. The nucleotide sequence showed that ADH2 transcription could be influenced by other transcription genes of glycolysis oriented due to the lack of specific activation sites for Adr1. Our study suggests that if Adr1 is not capable of promoting LfeADH2 activation, the transcription can be controlled by Rap1 and Sp1 due to their inherent roles. Therefore in future, it is interesting to observe ADH2 gene being highly regulated by these potential transcription factors and functioned as a promoter for yeast under high volume of ethanol and organic acids.

Matched MeSH terms: Ethanol
Fulltext Design and development of a modified runway model of mouse drug self-administration

Pandy V, Khan Y

Sci Rep, 2016;6:21944.
PMID: 26902717 DOI: 10.1038/srep21944

The present study established a novel mouse model of a runway drug self-administration in our laboratory. The operant runway apparatus consisted of three long runways arranged in a zig-zag manner. The methodology consisted of six distinct phases: habituation, preconditioning, conditioning, post-conditioning, extinction and reinstatement. The effects of saline were compared with escalating doses of either ethanol (0.5-4.0 g/kg, i.p), heroin (5-40 mg/kg, i.p), or nicotine (0.1-0.5mg/kg, i.p) administered in the goal box during the conditioning phase (day 1 to day 5). A significant decrease in the time of trained (conditioned) mice to reach the goal box confirmed the subjects' motivation to seek those drugs on day 6 (expression). The mice were then subjected to non-rewarded extinction trials for 5 days over which run times were significantly increased. After 5 days of abstinence, a priming dose of ethanol or heroin (1/5th of maximum dose used in conditioning) significantly reinstated the drug-seeking behavior. These results suggest that the modified runway model can serve as a powerful behavioral tool for the study of the behavioral and neurobiological bases of drug self-administration and, as such, is appropriate simple but powerful tool for investigating the drug-seeking behavior of laboratory mice.

Matched MeSH terms: Ethanol
Fulltext Antiarthritic activity of a polyherbal formulation against Freund's complete adjuvant induced arthritis in Female Wistar rats

Petchi RR, Parasuraman S, Vijaya C, Gopala Krishna SV, Kumar MK

J Basic Clin Pharm, 2015 Jun;6(3):77-83.
PMID: 26229343 DOI: 10.4103/0976-0105.160738

OBJECTIVES:
To formulate a polyherbal formulation and evaluate its antiarthritic activity against Freund's complete adjuvant induced arthritis in Female Wistar rats.

MATERIALS AND METHODS:
Glycosmis pentaphylla, Tridax procumbens, and Mangifera indica are well-known plants available throughout India and they are commonly used for the treatment of various diseases including arthritis. The polyherbal formulation was formulated using the ethanol extracts of the stem bark of G. pentaphylla , whole plant of T. procumbens, and leaves of M. indica. The polyherbal formulation contains the ethanol extracts of G. pentaphylla, T. procumbens, and M. indica in the ratio of 2:2:1. The quality of the finished product was evaluated as per the World Health Organization's guidelines for the quality control of herbal materials. Arthritis was induced in female Wistar rats using Freund's complete adjuvant (FCA), and the antiarthritic effect of polyherbal formulation was studied at doses of 250 and 500 mg/kg. The effects were compared with those of indomethacin (10 mg/kg). At the end of the study, blood samples were collected for biochemical and hematological analysis. The radiological examination was carried out before terminating the study.

RESULTS:
Polyherbal formulation showed significant antiarthritic activity at 250 and 500 mg/kg, respectively, and this effect was comparable with that of indomethacin. The antiarthritic activity of polyherbal formulation is supported by biochemical and hematological analysis.

CONCLUSION:
The polyherbal formulation showed signinicant antiarthritic activity against FCA-induced arthritis in female Wistar rats.

KEYWORDS:
Arthritis; Fingerprint analysis; Glycosmis pentaphylla; Mangifera indica; Tridax procumbens

Matched MeSH terms: Ethanol
Fulltext Ganoderma neo-japonicum Imazeki revisited: Domestication study and antioxidant properties of its basidiocarps and mycelia

Tan WC, Kuppusamy UR, Phan CW, Tan YS, Raman J, Anuar AM, et al.

Sci Rep, 2015;5:12515.
PMID: 26213331 DOI: 10.1038/srep12515

Mushroom cultivation benefits humankind as it deliberately encourages wild mushrooms to be commercially propagated while recycling agricultural wastes. Ganoderma neo-japonicum is a rare polypore mushroom found growing on decaying Schizostachyum brachycladium (a tropical bamboo) clumps in Malaysia. The Malaysian indigenous tribes including the Temuans and Temiars use the basidiocarps of G. neo-japonicum to treat various ailments including diabetes. In this study, the domestication of G. neo-japonicum in artificial logs of different agricultural residues was investigated. Sawdust promoted the mycelia spawn colonisation in the shortest period of 38 ± 0.5 days. However, only sawdust and bamboo dust supported the primodia formation. Complex medium supported mycelium growth in submerged cultures and 27.11 ± 0.43 g/L of mycelia was obtained after 2 weeks of cultivation at 28 °C and 200 rpm. Antioxidant potential in mushroom may be influenced by different cultivation and extraction methods. The different extracts from the wild and cultivated basidiocarps as well as mycelia were then tested for their antioxidant properties. Aqueous and ethanol extracts of mycelia and basidiocarps tested had varying levels of antioxidant activities. To conclude, domestication of wild G. neo-japonicum using agroresidues may ensure a continuous supply of G. neo-japonicum for its medicinal use while ensuring the conservation of this rare species.

Matched MeSH terms: Ethanol
Fulltext Evaluation of in-vitro antioxidant and antibacterial properties of Commelina nudiflora L. extracts prepared by different polar solvents

Kuppusamy P, Yusoff MM, Parine NR, Govindan N

Saudi J Biol Sci, 2015 May;22(3):293-301.
PMID: 25972750 DOI: 10.1016/j.sjbs.2014.09.016

The study explored on the commonly available weed plant Commelina nudiflora which has potential in-vitro antioxidant and antimicrobial activity. The different polar solvents such as ethanol, chloroform, dichloromethane, hexane and aqueous were used for the soxhlet extraction. The extracts were identified pharmacologically as important bioactive compounds and their potential free radical scavenging activities, and antimicrobial properties were studied. C. nudiflora extracts were monitored on their in-vitro antioxidant ability by DPPH and ABTS radical scavenging assay. Aqueous extract shows significant free radical scavenging activity of 63.4 mg/GAE and 49.10 mg/g in DPPH and ABTS respectively. Furthermore, the aqueous crude extract was used in antibacterial studies, which shows the highest inhibitory activity against Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi. Among all the extracts, aqueous extract of C. nudiflora has significant control over free radical scavenging activity and inhibition of the growth of food pathogenic bacteria. Also, the aqueous extract contains abundance of phenolics and flavonoids higher than other extracts. This study explored weed plant C. nudiflora as a potential source of antioxidant and antibacterial efficacy and identified various therapeutic value bioactive compounds from GC-MS analysis.

Matched MeSH terms: Ethanol
Bisulfite pretreatment changes the structure and properties of oil palm empty fruit bunch to improve enzymatic hydrolysis and bioethanol production

Tan L, Sun W, Li X, Zhao J, Qu Y, Choo YM, et al.

Biotechnol J, 2015 Jun;10(6):915-25.
PMID: 25866127 DOI: 10.1002/biot.201400733

Bisulfite pretreatment is a proven effective method for improving the enzymatic hydrolysis of empty fruit bunch (EFB) from oil palm for bioethanol production. In this study, we set out to determine the changes that occur in the structure and properties of EFB materials and fractions of hemicellulose and lignin during the bisulfite pretreatment process. The results showed that the crystallinity of cellulose in EFB increased after bisulfite pretreatment, whereas the EFB surface was damaged to various degrees. The orderly structure of EFB, which was maintained by hydrogen bonds, was destroyed by bisulfite pretreatment. Bisulfite pretreatment also hydrolyzed the glycosidic bonds of the xylan backbone of hemicellulose, thereby decreasing the molecular weight and shortening the xylan chains. The lignin fractions obtained from EFB and pretreated EFB were typically G-S lignin, and with low content of H units. Meanwhile, de-etherification occurred at the β-O-4 linkage, which was accompanied by polymerization and demethoxylation as a result of bisulfite pretreatment. The adsorption ability of cellulase differed for the various lignin fractions, and the water-soluble lignin fractions had higher adsorption capacity on cellulase than the milled wood lignin. In general, the changes in the structure and properties of EFB provided insight into the benefits of bisulfite pretreatment.

Matched MeSH terms: Ethanol
Fatty acid compositions in local sea cucumber, Stichopus chloronotus, for wound healing

Fredalina BD, Ridzwan BH, Abidin AA, Kaswandi MA, Zaiton H, Zali I, et al.

Gen. Pharmacol., 1999 Oct;33(4):337-40.
PMID: 10523072

Fatty acid profile from crude extracts of local sea cucumber Stichopus chloronotus was determined using gas chromatography (GC) technique. The extracts were prepared separately in methanol, ethanol, phosphate buffer saline (PBS), and distilled water as part of our study to look at the affinity of these solvents in extracting the lipid from sea cucumber. The PBS and distilled water extractions indicate water-soluble components, while the organic fractions are extracted in methanol and ethanol as organic solvents. Furthermore, water extraction is the conventional method practiced in Malaysia. In our analysis the C14:0 (myristic), C16:0 (palmitic), C18:0 (stearic), C18:2 (linoleic), C20:0 (arachidic), and C20:5 (eicosapentaenoic, EPA) were significantly different (p < 0.01) in the four solvent extractions. However, the PBS extraction contained a much higher percentage of EPA (25.69%) compared to 18.89% in ethanol, 7.84% in distilled water, and only 5.83% in methanol, and variances were significantly different (p < 0.01 ). On the other hand, C22:6 (docosahexaenoic acid or DHA) is much higher in water extraction (57.55%), in comparison to the others where only 3.63% in PBS and 1.20% in methanol, and this difference is significant at p < 0.01. No DHA was detected in ethanol extractions. Subsequently, C18:1 (oleic acid) was only detected in PBS (21.98%) and water extraction (7.50%). It is interesting that palmitic acid, C16:() was higher in methanol (20.82%) and ethanol (2.18%), while 12.55% was detected in PBS and only 2.20% in water extraction: and again this was significantly different at p < 0.01. Although our results have shown that all four solvents were different in terms of their ability to extract fatty acids, the major component for tissue repair was well preserved. Probably this is one of the important precocious steps when working with a delicate sea cucumber, in both experimental and/or at the preparative stages. Freshness of the sea cucumber samples is important when undertaking this type of experiment. Finally, we believe that the local sea cucumber S. chloronotus contains all the fatty acids required to play a potential active role in tissue repair.

Matched MeSH terms: Ethanol; Methanol
New crown-shaped polyoxovanadium(V) cluster cation with a mu(6)-sulfato anion and zwitterionic mu-(beta-alanine): crystal structure of [V(6)O(12)(OH)(3)(O(2)CCH(2)CH(2)NH(3))(3)(SO(4))][Na][SO(4)].13H(2)O

Ng CH, Lim CW, Teoh SG, Fun HK, Usman A, Ng SW

Inorg Chem, 2002 Jan 14;41(1):2-3.
PMID: 11782136

Treatment of vanadium(V) oxide with an ethanol-concentrated sulfuric acid mixture, followed by the addition of an equimolar amount of beta-alanine and sodium hydroxide, and finally raising the pH to 3.9 with sodium carbonate solution, under continuous heating in a water bath and in the presence of air, leads to the polyionic sodium cyclo-[mu(6)-(sulfato-O,O',O'')tris[mu-(beta-alanine-O,O')-mu-oxo]tris(mu-hydroxo-mu-oxo)hexa[oxovanadium(V)]] sulfate tridecahydrate which crystallizes in the monoclinic P2(1)/n space group [a = 9.5192(4), b = 20.1185(9), c = 22.6174(9) A, beta = 97.011(1) degrees; Z = 4]. The crown-shaped polyoxovanadium(V) cluster cation, with carboxylate-bridging amino acid ligands, has an Anderson structure with two unique capping sulfato ligands. Its structural analysis, together with IR, UV-vis, and preliminary data on its solution properties, is presented.

Matched MeSH terms: Ethanol
Fulltext Reinventing nano drug delivery systems for hydrophilic active ingredients in Ayurvedic lipid based formulations containing poly herbal decoction

Duraipandi S, Selvakumar V

J Ayurveda Integr Med, 2019 01 08;11(3):224-227.
PMID: 30635246 DOI: 10.1016/j.jaim.2018.01.008

BACKGROUND: Anu Tailam, an Ayurvedic medicated oil where 'anu' meant for atom and 'tailam' meant for oil and virtually meant for 'oil of subtle or atomic size particles'. Since the major active ingredients in this formulation are incorporated from the polyherbal decoction, it is expected to contain predominantly water soluble ingredients.
OBJECTIVES: It is hypothesized that these polar active botanical ingredients are present in the formulation should be either suspended in the form of submicron particles or entrapped in the submicron vesicular structures since the formulation did not show any precipitation or phase separation instead showed a monophasic oily liquid with very little moisture.
MATERIALS AND METHODS: In the present investigation, the micro architecture of the anu tailam is studied via column chromatography and high performance thin layer chromatography to prove the contents are polar hydrophilic compounds followed by optical microscopy, photon correlation Spectroscopy (PCS) and environmental scanning electron microscope (ESEM) to study the particle/vesicle size of the formulation.
RESULTS: In this study, it was proved that the formulation contained only polar ingredients and can be extracted in polar solvents like methanol and ethanol. It was also found that the formulation taken for study contained nano particles of the active botanical ingredients embedded in a network of vesicular structures of the lipid base.
CONCLUSION: The selected Ayurvedic formulation 'anutailam' found to contain novel nano drug delivery system to deliver water soluble ingredients across barriers.

Matched MeSH terms: Ethanol; Methanol
Fulltext Graphene/PVA buckypaper for strain sensing application

Mehmood A, Mubarak NM, Khalid M, Jagadish P, Walvekar R, Abdullah EC

Sci Rep, 2020 11 18;10(1):20106.
PMID: 33208815 DOI: 10.1038/s41598-020-77139-2

Strain sensors in the form of buckypaper (BP) infiltrated with various polymers are considered a viable option for strain sensor applications such as structural health monitoring and human motion detection. Graphene has outstanding properties in terms of strength, heat and current conduction, optics, and many more. However, graphene in the form of BP has not been considered earlier for strain sensing applications. In this work, graphene-based BP infiltrated with polyvinyl alcohol (PVA) was synthesized by vacuum filtration technique and polymer intercalation. First, Graphene oxide (GO) was prepared via treatment with sulphuric acid and nitric acid. Whereas, to obtain high-quality BP, GO was sonicated in ethanol for 20 min with sonication intensity of 60%. FTIR studies confirmed the oxygenated groups on the surface of GO while the dispersion characteristics were validated using zeta potential analysis. The nanocomposite was synthesized by varying BP and PVA concentrations. Mechanical and electrical properties were measured using a computerized tensile testing machine, two probe method, and hall effect, respectively. The electrical conducting properties of the nanocomposites decreased with increasing PVA content; likewise, electron mobility also decreased while electrical resistance increased. The optimization study reports the highest mechanical properties such as tensile strength, Young's Modulus, and elongation at break of 200.55 MPa, 6.59 GPa, and 6.79%, respectively. Finally, electrochemical testing in a strain range of ε ~ 4% also testifies superior strain sensing properties of 60 wt% graphene BP/PVA with a demonstration of repeatability, accuracy, and preciseness for five loading and unloading cycles with a gauge factor of 1.33. Thus, results prove the usefulness of the nanocomposite for commercial and industrial applications.

Matched MeSH terms: Ethanol
Fulltext Determination of Temperature-Dependent Coefficients of Viscosity and Surface Tension of Tamarind Seeds (Tamarindus indica L.) Polymer

Malviya R, Jha S, Fuloria NK, Subramaniyan V, Chakravarthi S, Sathasivam K, et al.

Polymers (Basel), 2021 Feb 18;13(4).
PMID: 33670569 DOI: 10.3390/polym13040610

The rheological properties of tamarind seed polymer are characterized for its possible commercialization in the food and pharmaceutical industry. Seed polymer was extracted using water as a solvent and ethyl alcohol as a precipitating agent. The temperature's effect on the rheological behavior of the polymeric solution was studied. In addition to this, the temperature coefficient, viscosity, surface tension, activation energy, Gibbs free energy, Reynolds number, and entropy of fusion were calculated by using the Arrhenius, Gibbs-Helmholtz, Frenkel-Eyring, and Eotvos equations, respectively. The activation energy of the gum was found to be 20.46 ± 1.06 kJ/mol. Changes in entropy and enthalpy were found to be 23.66 ± 0.97 and -0.10 ± 0.01 kJ/mol, respectively. The calculated amount of entropy of fusion was found to be 0.88 kJ/mol. A considerable decrease in apparent viscosity and surface tension was produced when the temperature was raised. The present study concludes that the tamarind seed polymer solution is less sensitive to temperature change in comparison to Albzia lebbac gum, Ficus glumosa gum and A. marcocarpa gum. This study also concludes that the attainment of the transition state of viscous flow for tamarind seed gum is accompanied by bond breaking. The excellent physicochemical properties of tamarind seed polymers make them promising excipients for future drug formulation and make their application in the food and cosmetics industry possible.

Matched MeSH terms: Ethanol
Fulltext A New Model of Alcoholic Fermentation under a Byproduct Inhibitory Effect

Zentou H, Zainal Abidin Z, Yunus R, Awang Biak DR, Abdullah Issa M, Yahaya Pudza M

ACS Omega, 2021 Feb 16;6(6):4137-4146.
PMID: 33644536 DOI: 10.1021/acsomega.0c04025

Despite the advantages of continuous fermentation whereby ethanol is selectively removed from the fermenting broth to reduce the end-product inhibition, this process can concentrate minor secondary products to the point where they become toxic to the yeast. This study aims to develop a new mathematical model do describe the inhibitory effect of byproducts on alcoholic fermentation including glycerol, lactic acid, acetic acid, and succinic acid, which were reported as major byproducts during batch alcoholic fermentation. The accumulation of these byproducts during the different stages of batch fermentation has been quantified. The yields of total byproducts, glycerol, acetic acid, and succinic acid per gram of glucose were 0.0442, 0.023, 0.0155, and 0.0054, respectively. It was found that the concentration of these byproducts linearly increases with the increase in glucose concentration in the range of 25-250 g/L. The results have also showed that byproduct concentration has a significant inhibitory effect on specific growth coefficient (μ) whereas no effect was observed on the half-velocity constant (Ks). A new mathematical model of alcoholic fermentation was developed considering the byproduct inhibitory effect, which showed a good performance and more accuracy compared to the classical Monod model.

Matched MeSH terms: Ethanol
Fulltext Electrodeposited Hybrid Biocathode-Based CO2 Reduction via Microbial Electro-Catalysis to Biofuels

Anwer AH, Khan N, Umar MF, Rafatullah M, Khan MZ

Membranes (Basel), 2021 Mar 22;11(3).
PMID: 33810075 DOI: 10.3390/membranes11030223

Microbial electrosynthesis is a new approach to converting C1 carbon (CO2) to more complex carbon-based products. In the present study, CO2, a potential greenhouse gas, was used as a sole carbon source and reduced to value-added chemicals (acetate, ethanol) with the help of bioelectrochemical reduction in microbial electrosynthesis systems (MES). The performance of MES was studied with varying electrode materials (carbon felt, stainless steel, and cobalt electrodeposited carbon felt). The MES performance was assessed in terms of acetic acid and ethanol production with the help of gas chromatography (GC). The electrochemical characterization of the system was analyzed with chronoamperometry and cyclic voltammetry. The study revealed that the MES operated with hybrid cobalt electrodeposited carbon felt electrode yielded the highest acetic acid (4.4 g/L) concentration followed by carbon felt/stainless steel (3.7 g/L), plain carbon felt (2.2 g/L), and stainless steel (1.87 g/L). The alcohol concentration was also observed to be highest for the hybrid electrode (carbon felt/stainless steel/cobalt oxide is 0.352 g/L) as compared to the bare electrodes (carbon felt is 0.22 g/L) tested, which was found to be in correspondence with the pH changes in the system. Electrochemical analysis revealed improved electrotrophy in the hybrid electrode, as confirmed by the increased redox current for the hybrid electrode as compared to plain electrodes. Cyclic voltammetry analysis also confirmed the role of the biocatalyst developed on the electrode in CO2 sequestration.

Matched MeSH terms: Ethanol
Fulltext In vitro antileptospiral activity of trigona thoracia propolis and its synergistic effects with commonly prescribed antibiotics

Siti Radziah Ismail

IIUM Medical Journal Malaysia, 2020;19(1):13-22.
MyJurnal

Introduction: Trigona thoracica propolis is known to have antimicrobial properties, however its
antileptospiral properties and its synergistic effects with commonly prescribed antibiotics are scarcely
documented. This study aimed to evaluate the antileptospiral properties of Trigona thoracica against
pathogenic Leptospira species (spp.) and to study its synergistic effects with commonly prescribed
antibiotics. Materials and Methods: The tested Leptospira serovars were Australis, Bataviae, Canicola and
Javanica. Aqueous extract propolis (AEP) and ethanolic extracts propolis (EEP) were used. Broth dilution
methods were used to determine the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal
Concentration (MBC) and the synergistic effects between the propolis and the tested antibiotics. The
synergistic effects was evaluated by using the fractional inhibitory concentration (FIC) index. Morphological
changes of the treated Leptospira were observed under a Scanning Electron Microscope (SEM). Results: The
AEP and EEP were found to have antileptospiral properties against the tested Leptospira spp. The synergy
result showed that only combination of AEP and penicillin G against serovar Australis has demonstrated
synergistic effect with the FIC index of 0.38. Morphological study using SEM showed significant structural
changes of the treated Leptospira spp. Conclusions: The result suggests that Trigona thoracica propolis could
potentially be used as either a complimentary or an alternative therapeutic agent against pathogenic
Leptospira spp.

Matched MeSH terms: Ethanol
Surfactant-functionalised magnetic ferum oxide coupled with high performance liquid chromatography for the extraction of phenol

Beh SY, Md Saleh N, Asman S

Anal Methods, 2021 02 07;13(5):607-619.
PMID: 33480366 DOI: 10.1039/d0ay02166k

The usage of phenols in the marketplace has been increasing tremendously, which has raised concerns about their toxicity and potential effect as emerging pollutants. Phenol's structure has closely bonded phenyl and hydroxy groups, thereby making its functional characteristics closely similar to that of alcohol. As a result, phenol is used as a base compound for commercial home-based products. Hence, a simple and efficient procedure is required to determine the low concentration of phenols in environmental water samples. In this research, a method of combining magnetic nanoparticles (MNPs) with surfactant Sylgard 309 was developed to overcome the drawbacks in the classical extraction methods. In addition, this developed method improved the performance of extraction when MNPs and the surfactant Sylgard 309 were used separately, as reported in the previous research. This MNP-Sylgard 309 was synthesised by the coprecipitation method and attracts phenolic compounds in environmental water samples. Response surface methodology was used to study the parameters and responses in order to obtain an optimised condition using MNP-Sylgard 309. The parameters included the effect of pH, extraction time, and concentration of the analyte. Meanwhile, the responses measured were the peak area of the chromatogram and the percentage recovery. From this study, the results of the optimum conditions for extraction using MNP-Sylgard 309 were pH 7, extraction time of 20 min, and analyte concentration of 10.0 μg mL-1. Under the optimized conditions, MNP-Sylgard 309 showed a low limit of detection of 0.665 μg mL-1 and the limit of quantification was about 2.219 μg mL-1. MNP-Sylgard 309 was successfully applied on environmental water samples such as lake and river water. High recovery (76.23%-110.23%) was obtained.

Matched MeSH terms: Ethanol
Fulltext Oral microbiome, nutrition and their role in oral carcinogenesis

Mohd Hafiz Arzmi

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):10-10.
MyJurnal

A balanced oral microbiome is essential in maintaining a healthy oral cavity. Oral microbiome comprises of var-ious microorganisms that belong to different kingdoms, including bacteria (bacteriome) and fungal (mycobiome). Multiple factors have been shown in oral carcinogenesis including alcohol consumption, tobacco smoking, betel nut chewing and microbial infections. Since the oral cavity comprises of various microbial kingdoms, thus, in-ter-kingdom interactions are suggested in promoting oral carcinogenesis. Dysbiosis, which is defined as imbalance inter-kingdom microbiome, alone may not cause oral carcinogenesis; thus, it is suggested that nutritional factor may also play a vital role in this disease development. A recent study has shown that sucrose consumption can induce the production of glucosyltransferases (gtfs) by Streptococcus mutans which lead to the increasing attachment of Candida albicans in polymicrobial biofilms form. The yeast has been reported to be potentially involved in oral carcinogenesis, particularly in the immunocompromised patient. This is due to the inflammation that is caused by candidal infection, which increases pro-inflammatory cytokines such as interleukin-6, interleukin-8 and interleu-kin-10, that have been linked to oral carcinogenesis. However, further study is needed to conform to the claim. In addition, over-consumption of alcoholic beverages has also been related to carcinogenesis which the ethanol has been reported to be converted into acetaldehyde by C. albicans using acetaldehyde dehydrogenases enzymes. In Malaysia, oral cancer has also been related to the consumption of cured and salted fish, which mostly consumed by the Chinese ethnics. However, its relationship to oral microbiome remains unclear. In conclusion, oral microbiome and nutrition may have a role in oral carcinogenesis; however, further study is needed to elucidate the role of both factors in oral cancer development.

Matched MeSH terms: Ethanol
Tea from the drinking to the synthesis of metal complexes and fabrication of PVA based polymer composites with controlled optical band gap

Brza MA, Aziz SB, Anuar H, Ali F, Dannoun EMA, Mohammed SJ, et al.

Sci Rep, 2020 Oct 22;10(1):18108.
PMID: 33093604 DOI: 10.1038/s41598-020-75138-x

In the present study black tea extract (BTE) solution which is familiar for drinking was used to prepare cerium metal-complexes (Ce(III)-complex). The prepared Ce(III)-complex was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and UV-Vis spectroscopy. The results indicate that BTE solution is a novel green coordination chemistry approach for the synthesis of metal complexes. The outcomes signify that coordination occurs between cerium cations and polyphenols. The synthesis of metal-complexes with superior absorption performance in the visible region is a challenge for optoelectronic device applications. The suspended Ce(III)-complex in distilled water was mixed with poly (vinyl alcohol) (PVA) polymer to fabricate PVA/ Ce(III)-complex composites with controlled optical properties. The PVA/Ce(III)-complexes composite films were characterized by FTIR, XRD, and UV-Vis spectroscopy. The XRD findings confirms the amorphous structure for the synthesized Ce(III)-complexes. The addition of Ce(III)-complex into the PVA host polymer led to the growth of polymer composites with controllable small optical band gaps. It is shown by the FTIR spectra of the composite films that the functional groups of the host PVA have a vigorous interaction with the Ce(III)-complex. The XRD deconvolution on PVA composites reveals the amorphous phase enlargement with increasing Ce(III)-complex concentration. It is indicated in the atomic force microscopy (AFM) that the surface roughness in the doped PVA films increases with the increase of the Ce(III)-complex. There is a decrease in absorption edge from 5.7 to 1.7 eV. It becomes possible to recognize the type of electron transition by studying both the Tauc's model and optical dielectric loss (ɛi) parameter.

Matched MeSH terms: Ethanol

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