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Biotechnology Journal Jan 2015The biotechnological production of biodiesel is based on transesterification/esterification reactions between a source of fatty acids and a short-chain alcohol, usually... (Review)
Review
The biotechnological production of biodiesel is based on transesterification/esterification reactions between a source of fatty acids and a short-chain alcohol, usually methanol, catalysed by enzymes belonging to the class known as lipases. Several lipases used in industrial processes, although stable in the presence of other organic solvents, are inactivated by methanol at or below the concentration optimal for biodiesel production, making it necessary to use stepwise methanol feeding or pre-treatment of the enzyme. In this review article we focus on what is currently know about methanol inactivation of lipases, a phenomenon which is not common to all lipase enzymes, with the goal of improving the biocatalytic process. We suggest that different mechanisms can lead to inactivation of different lipases, in particular substrate inhibition and protein unfolding. Attempts to improve the performances of methanol sensitive lipases by mutagenesis as well as process engineering approaches are also summarized.
Topics: Biofuels; Biotechnology; Enzyme Stability; Lipase; Methanol
PubMed: 25046365
DOI: 10.1002/biot.201400158 -
International Journal of Molecular... Sep 2017C₁ metabolism in plants is known to be involved in photorespiration, nitrogen and amino acid metabolism, as well as methylation and biosynthesis of metabolites and...
C₁ metabolism in plants is known to be involved in photorespiration, nitrogen and amino acid metabolism, as well as methylation and biosynthesis of metabolites and biopolymers. Although the flux of carbon through the C₁ pathway is thought to be large, its intermediates are difficult to measure and relatively little is known about this potentially ubiquitous pathway. In this study, we evaluated the C₁ pathway and its integration with the central metabolism using aqueous solutions of C-labeled C₁ and C₂ intermediates delivered to branches of the tropical species via the transpiration stream. Delivery of [C]methanol and [C]formaldehyde rapidly stimulated leaf emissions of [C]methanol, [C]formaldehyde, [C]formic acid, and CO₂, confirming the existence of the C1 pathway and rapid interconversion between methanol and formaldehyde. However, while [C]formate solutions stimulated emissions of CO₂, emissions of [C]methanol or [C]formaldehyde were not detected, suggesting that once oxidation to formate occurs it is rapidly oxidized to CO₂ within chloroplasts. C-labeling of isoprene, a known photosynthetic product, was linearly related to CO₂ across C₁ and C₂ ([C₂]acetate and [2-C]glycine) substrates, consistent with reassimilation of C₁, respiratory, and photorespiratory CO₂. Moreover, [C]methanol and [C]formaldehyde induced a quantitative labeling of both carbon atoms of acetic acid emissions, possibly through the rapid turnover of the chloroplastic acetyl-CoA pool via glycolate oxidation. The results support a role of the C₁ pathway to provide an alternative carbon source for glycine methylation in photorespiration, enhance CO₂ concentrations within chloroplasts, and produce key C₂ intermediates (e.g., acetyl-CoA) central to anabolic and catabolic metabolism.
Topics: Butadienes; Carbon; Carbon Isotopes; Formaldehyde; Formates; Hemiterpenes; Isotope Labeling; Metabolic Networks and Pathways; Methanol; Pentanes; Trees; Volatile Organic Compounds
PubMed: 28946627
DOI: 10.3390/ijms18102045 -
Molecules (Basel, Switzerland) Apr 2023The purpose of this work was to investigate, for the first time to our knowledge, the chemical composition and bioactivity of methanolic extracts (roots, stems, leaves,...
The purpose of this work was to investigate, for the first time to our knowledge, the chemical composition and bioactivity of methanolic extracts (roots, stems, leaves, and flowers) from (L.) Chevall. that grows wild in northern Morocco (the Tangier-Tetouan-Al Hoceima region). The phenolic and flavonoid contents were determined by spectrophotometer methods, and the composition of derivatized methanolic extracts from using --bis(trimethylsilyl) trifluoroacetamide (BSTFA) was analyzed by gas chromatography-mass spectrometry (GC-MS). The antioxidant activity was carried out by applying the 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and DPPH (2,2-diphenyl-1-picrylhydrazyl) tests. The micro-dilution technique was chosen to investigate the antimicrobial activity of methanolic extracts against two bacterial strains and three fungal species. The results showed that the values of total phenolic and flavonoid contents were found to be higher in flower extracts (30.55 ± 0.85 mg of gallic acid equivalents (GAE)/g of dried weight (DW) and 26.00 ±1.34 mg of quercetin equivalents (QE)/g DW, respectively). Other groups of chemical compounds were revealed by GC-MS, such as carbohydrates (27.25-64.87%), fatty acids (1.58-9.08%), organic acids (11.81-18.82%), and amino acids (1.26-7.10%). Root and flower methanolic extracts showed the highest antioxidant activity using ABTS (39.49 mg of Trolox equivalents (TE)/g DW) and DPPH (36.23 mg TE/g DW), respectively. A positive correlation between antioxidant activity and polyphenol and flavonoid amounts was found. Antibacterial tests showed that the best activity was presented by the leaf extract against (minimum inhibitory concentration (MIC) = minimum bactericidal concentration (MBC) = 20 mg/mL) and (MIC of 30 mg/mL and MBC of 35 mg/mL). was more sensitive to the extracts compared to . All extracts showed antifungal activity against , with the best efficacy reported by the flower and leaf extracts (MIC = 1.25 mg/mL and minimum fungicidal concentration (MFC) = 2.5 mg/mL). In general, extracts of appeared less effective against and .
Topics: Plant Extracts; Antioxidants; Staphylococcus aureus; Escherichia coli; Morocco; Flavonoids; Phenols; Methanol
PubMed: 37049958
DOI: 10.3390/molecules28073196 -
Evaluation of Cytotoxic Effects of Methanolic Extract of Pergularia tomentosa L Growing Wild in KSA.Asian Pacific Journal of Cancer... Feb 2021Pergularia tomentosa is a member of the Apocynaceae family found in a wide geographical region including the Gulf region, North Africa and the Middle East. It is known...
BACKGROUND
Pergularia tomentosa is a member of the Apocynaceae family found in a wide geographical region including the Gulf region, North Africa and the Middle East. It is known as Fattaka, Ghalqa or Am Lebina in Saudi Arabia, It is used as a remedy for the treatment of skin sores, asthma, and bronchitis.
OBJECTIVE
This study aims to investigate the cytotoxic effects of methanolic extract and Latex (milky secretion) extract.
METHODS
The stem of Pergularia tomentosa was cut, air dried and soaked for 72 h with methanol repeatedly three times. The crude latex (milk extract) was collected from healthy stem parts of P. tomentosa L by cutting the petiole of leaves, and left to flow where a thick white liquid (Milky) were secreted, collected in amber glass tube and extracted with methanol. Further, the methanolic extract was fractionated by subsequent extraction with various solvents, viz. n-hexane, ethyl acetate and methanol. The cytotoxic effects of Pergularia tomentosa L were evaluated using three cancer cell lines of colon carcinoma (HCT-116), hepatocellular carcinoma (HepG2) and breast carcinoma (MCF-7). The cytotoxic effects of Pergularia tomentosa L extracts against HCT-116, HepG2, and MCF-7 were determined by crystal violet staining method.
RESULTS
The potency of plant extract to decrease the cell viability of human cancer cells was arranged in descending order as follows: Methanol extract (IC50 = 10.2 μg/ml, 13.6 μg/ml and 29.5μg/ml, respectively). > Milky secretion extract (IC50 = 52.6 μg/ml, 58.6 μg/ml and 120 µg/ml, respectively). Methanolic extract was strong cytotoxic activity against HCT-116 and HepG2 (IC50= 10.2, 13.6 µg/ml, respectively) and moderately activity against MCF-7 (IC50= 29.5 µg/ml). The Milky extract exhibited moderate activity against HCT-116 and HepG2 (IC50= 52.6-58.6 µg/ml, respectively) and weak activity against MCF-7 (120.0 µg/ml).
CONCLUSION
The methanol extract of Pergularia tomentosa L showed higher cytotoxic effect as compared to the Latex (Milky secretion) extract. These extracts can be used as natural antitumor. In Future modern chromatographic separations are needed to get more quantity of metabolites. Further detailed investigation of the isolated metabolites is required to identify the phytoconstituents responsible for antioxidant and cytotoxic effects.
.Topics: Antineoplastic Agents, Phytogenic; Apocynaceae; Apoptosis; Cell Proliferation; Humans; Methanol; Neoplasms; Plant Extracts; Tumor Cells, Cultured
PubMed: 33576214
DOI: 10.31557/APJCP.2021.22.S1.67 -
BioMed Research International 2022The recent study was designed to explore , , , and using methanolic (MeOH) extract. Their subfractions were examined against urease, carbonic anhydrase II (CA-II),...
The recent study was designed to explore , , , and using methanolic (MeOH) extract. Their subfractions were examined against urease, carbonic anhydrase II (CA-II), -glucosidase enzymes, and free radicals scavenging significance based on local practices via standard methods. Significance potential against the urease enzyme was presented by ethyl acetate fraction (EtOAc) of with ( = 125 ± 1.75 g/mL), whereas the ( = 146 ± 1.39 g/mL) in the EtOAc was found efficient to scavenge the free radicals. Besides, that appreciable capacity was observed by the , , , and as compared to the standard acarbose (IC = 377.24 ± 1.14 g/mL). Maximum significance was noticed in methanolic (MeOH) extract of and presented carbonic anhydrase CA-II (IC = 5.1 ± 0.20 g/mL) inhibition as compared to the standard (acetazolamide). We are reporting, for the first time, the CA-II inhibition of all the selected medicinal plants and -glucosidase, urease, and antioxidant activities of the . Thus, further screening is needed to isolate the promising bioactive ingredients which act as an alternative remedy to scavenge the free radicals, antiulcer, and act as a potential source to develop new antidiabetic drugs for controlling postprandial blood sugar as well as carbonic anhydrase inhibitors.
Topics: Antioxidants; Free Radicals; Methanol; Oman; Plant Extracts; Plants, Medicinal; Urease; alpha-Glucosidases
PubMed: 35872867
DOI: 10.1155/2022/7880387 -
Molecules (Basel, Switzerland) Jun 2017The lipophilicity of two series of thiosemicarbazide derivatives was assessed by the RP-HPLC method with the RP-18 chromatographic column and the methanol-water mixture...
The lipophilicity of two series of thiosemicarbazide derivatives was assessed by the RP-HPLC method with the RP-18 chromatographic column and the methanol-water mixture as the mobile phase. Distribution coefficients were compared to calculated values generated by commonly used software and quantum chemical calculations. The reliability of the predictions was evaluated using the correlation matrix and PCA. For 4-benzoylthiosemicarbazides, a high correlation between theoretical and experimental parameters was obtained using the algorithm, while for 4-aryl/(cyclohexyl)thiosemicarbazides, the parameter was strongly correlated with the experimentally obtained .
Topics: Algorithms; Chromatography, High Pressure Liquid; Hydrophobic and Hydrophilic Interactions; Methanol; Quantum Theory; Semicarbazides; Software; Water
PubMed: 28594381
DOI: 10.3390/molecules22060952 -
Molecules (Basel, Switzerland) Jun 2020The mechanism of reactions of silatranes and germatranes, and their bicyclic and monocyclic analogues with one molecule of methanol or ethanol, was studied at the...
Mechanism of Reactions of 1-Substituted Silatranes and Germatranes, 2,2-Disubstituted Silocanes and Germocanes, 1,1,1-Trisubstituted Hyposilatranes and Hypogermatranes with Alcohols (Methanol, Ethanol): DFT Study.
The mechanism of reactions of silatranes and germatranes, and their bicyclic and monocyclic analogues with one molecule of methanol or ethanol, was studied at the Density Functional Theory (DFT) B3PW91/6-311++G(df,p) level of theory. Reactions of 1-substituted sil(germ)atranes, 2,2-disubstituted sil(germ)ocanes, and 1,1,1-trisubstituted hyposil(germ)atranes with alcohol (methanol, ethanol) proceed in one step through four-center transition states followed by the opening of a silicon or germanium skeleton and the formation of products. According to quantum chemical calculations, the activation energies and Gibbs energies of activation of reactions with methanol and ethanol are close, their values decrease in the series of atranes-ocanes-hypoatranes for interactions with both methanol and ethanol. The reactions of germanium-containing derivatives are characterized by lower activation energies in comparison with the reactions of corresponding silicon-containing compounds. The annular configurations of the product molecules with electronegative substituents are stabilized by the transannular N→X (X = Si, Ge) bond and different intramolecular hydrogen contacts with the participation of heteroatoms of substituents at the silicon or germanium.
Topics: Ethanol; Heterocyclic Compounds; Methanol; Models, Chemical; Quantum Theory
PubMed: 32560499
DOI: 10.3390/molecules25122803 -
Molecules (Basel, Switzerland) Dec 2022In this study, the methanolic and infusion extracts of two species, and subsp. , were tested for their chemical composition and biological abilities (antioxidant,...
In this study, the methanolic and infusion extracts of two species, and subsp. , were tested for their chemical composition and biological abilities (antioxidant, enzyme inhibitory and anti-inflammatory effects). The extracts yielded total phenolic and flavonoid contents in the range of 83.43-127.52 mg GAE/g and 9.41-46.34 mg RE/g, respectively. HPLC analysis revealed rosmarinic acid to be a major component of the studied extracts (15.85-26.43%). The best ABTS radical scavenging ability was observed in the methanol extract of with 379.11 mg TE/g, followed by in the methanol extract of (360.93 mg TE/g). In the CUPRAC assay, the highest reducing ability was also found in the methanol extract of with 802.22 mg TE/g. The phosphomolybdenum ability ranged from 2.39 to 3.61 mmol TE/g. In terms of tyrosinase inhibitory effects, the tested methanol extracts (83.18-89.66 mg KAE/g) were higher than the tested water extracts (18.74-19.11 mg KAE/g). Regarding the BChE inhibitory effects, the methanol extracts were active on the enzyme while the water extracts showed no inhibitory effect on it. Overall, the methanolic extracts showed better enzyme inhibition compared to the infusion extracts. Molecular docking also showed the selected exhibited potential binding affinities with all enzymes, with a preference for cholinesterases. Additionally, the extracts were effective in attenuating the LPS-induced increase in COX-2 and IL-6 gene expression in isolated colon, thus indicating promising anti-inflammatory effects. The preliminary results of this study suggest that these species are good natural sources of antioxidants and also provide some scope as enzyme inhibitors, most likely due to their bioactive contents such as phenolic acids, and thus can be exploited for different applications related to health promotion and disease prevention.
Topics: Lamiaceae; Molecular Docking Simulation; Methanol; Plant Extracts; Antioxidants; Thymus Plant; Water; Anti-Inflammatory Agents
PubMed: 36558163
DOI: 10.3390/molecules27249029 -
Scientific Reports Apr 2022Osteoporosis affects millions of people worldwide. As such, this study assessed the macrophage-dependent in vitro anti-osteoporosis, phytochemical profile and...
Osteoporosis affects millions of people worldwide. As such, this study assessed the macrophage-dependent in vitro anti-osteoporosis, phytochemical profile and hepatotoxicity effects in zebrafish larvae of the stem bark extracts of P. africana. Mouse bone marrow macrophages (BMM) cells were plated in 96-well plates and treated with P. africana methanolic bark extracts at concentrations of 0, 6.25, 12.5, 25, and 50 µg/ml for 24 h. The osteoclast tartrate-resistant acid phosphatase (TRAP) activity and cell viability were measured. Lipopolysaccharides (LPS) induced Nitrite (NO) and interleukin-6 (IL-6) production inhibitory effects of P. africana bark extracts (Methanolic, 150 µg/ml) and β-sitosterol (100 µM) were conducted using RAW 264.7 cells. Additionally, inhibition of IL-1β secretion and TRAP activity were determined for chlorogenic acid, catechin, naringenin and β-sitosterol. For toxicity study, zebrafish larvae were exposed to different concentrations of 25, 50, 100, and 200 µg/ml P. africana methanolic, ethanolic and water bark extracts. Dimethyl sulfoxide (0.05%) was used as a negative control and tamoxifen (5 µM) and dexamethasone (40 µM or 80 µM) were positive controls. The methanolic P. africana extracts significantly inhibited (p < 0.001) TRAP activity at all concentrations and at 12.5 and 25 µg/ml, the extract exhibited significant (p < 0.05) BMM cell viability. NO production was significantly inhibited (all p < 0.0001) by the sample. IL-6 secretion was significantly inhibited by P. africana methanolic extract (p < 0.0001) and β-sitosterol (p < 0.0001) and further, chlorogenic acid and naringenin remarkably inhibited IL-1β production. The P. africana methanolic extract significantly inhibited RANKL-induced TRAP activity. The phytochemical study of P. africana stem bark revealed a number of chemical compounds with anti-osteoporosis activity. There was no observed hepatocyte apoptosis in the liver of zebrafish larvae. In conclusion, the stem bark of P. africana is non-toxic to the liver and its inhibition of TRAP activity makes it an important source for future anti-osteoporosis drug development.
Topics: Animals; Chlorogenic Acid; Gas Chromatography-Mass Spectrometry; Humans; Interleukin-6; Methanol; Mice; Osteoporosis; Phytochemicals; Plant Bark; Plant Extracts; Prunus africana; RAW 264.7 Cells; Zebrafish
PubMed: 35487926
DOI: 10.1038/s41598-022-10629-7 -
Marine Pollution Bulletin May 2023Historical exposure of the marine environment to 2,4,6-trinitrotoluene (TNT) happened due to the dumping of left-over munitions. Despite significant research on TNT...
Historical exposure of the marine environment to 2,4,6-trinitrotoluene (TNT) happened due to the dumping of left-over munitions. Despite significant research on TNT decontamination, the potential of marine microbiome for TNT degradation remains only little explored. In this study, TNT degradation experiments were conducted with sediment located near the World War I munition dumpsite - Paardenmarkt in the Belgian part of North Sea. A slow removal was observed using TNT as sole source of C and N, which could be enhanced by adding methanol. Degradation was reflected in nitro-reduced metabolites and microbial growth. 16S Illumina sequencing analysis revealed several enriched genera that used TNT as a sole source of C and N - Colwellia, Thalossospira, and Methylophaga. Addition of methanol resulted in increased abundance of Methylophaga, which corresponded to the rapid removal of TNT. Methanol enhanced the degradation by providing additional energy and establishing syntrophic association between methanol-utilizing and TNT-utilizing bacteria.
Topics: Methanol; Trinitrotoluene; Bacteria; North Sea
PubMed: 37001405
DOI: 10.1016/j.marpolbul.2023.114866