Cunninghamella Elegans Research Articles

Isolation and Identification of Fungi Associated with Decay of Quercus mongolica

The Quercus mongolica has a high utilization value in industrial economic sector. The species is distributed throughout Korea, however, the damage caused by deterioration such as discoloration and decay is severe. For this reason, the deterioration of Q. mongolica is an obstacle to its use as wood, but research on deterioration factors is insufficient. In this study, we focused on fungi as a factor influencing the deterioration of Q. mongolica, and isolated and identified the fungi from the deteriorated Q. mongolica. In additions, in order to confirm whether the identified fungi actually affects wood deterioration, enzyme activities of the identified fungi were evaluated and related mass loss of wood treated with the fungi was measured by wood decay test. As a result of sequencing analysis using the ITS region of the genomic DNA of the fungi isolated from Q. mongolica, Mucor circinelloides, Cunninghamella elegans, and Umbelopsis isabellina 3 species belonging to Mucoromycota phylum, and Ophiostoma piceae and Aureobasidium melanogenum 2 species belonging to Ascomycota phylum were identified. These five fungi had enzyme (i.e. cellulase, laccase) activities related to wood decay and reduced the mass of heartwood and sapwood of Q. mongolica in practice. In particular, O. piceae and A. melanogenum, which have both cellulase and laccase activities, showed 6.9% and 1.5% mass loss, respectively. These results indicated that five fungi identified in this study influence the deterioration of Q. mongolica and are wood decaying fungi for Q. mongolica potentially.

25CN-NBOMe Metabolites in Rat Urine, Human Liver Microsomes and C.elegans-Structure Determination and Synthesis of the Most Abundant Metabolites.

N-Benzylphenethylamines are novel psychedelic substances increasingly used for research, diagnostic, or recreational purposes. To date, only a few metabolism studies have been conducted for N-2-methoxybenzylated compounds (NBOMes). Thus, the available 2,5-dimethoxy-4-(2-((2-methoxybenzyl)amino)ethyl)benzonitrile (25CN-NBOMe) metabolism data are limited. Herein, we investigated the metabolic profile of 25CN-NBOMe in vivo in rats and in vitro in Cunninghamella elegans (C. elegans) mycelium and human liver microsomes. Phase I and phase II metabolites were first detected in an untargeted screening, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) identification of the most abundant metabolites by comparison with in-house synthesized reference materials. The major metabolic pathways described within this study (mono- and bis-O-demethylation, hydroxylation at different positions, and combinations thereof, followed by the glucuronidation, sulfation, and/or N-acetylation of primary metabolites) generally correspond to the results of previously reported metabolism of several other NBOMes. The cyano functional group was either hydrolyzed to the respective amide or carboxylic acid or remained untouched. Differences between species should be taken into account in studies of the metabolism of novel substances.

Investigation of Equine In Vivo and In Vitro Derived Metabolites of the Selective Androgen Receptor Modulator (SARM) ACP-105 for Improved Doping Control.

Selective Androgen Receptor Modulators (SARMs) have anabolic properties but less adverse effects than anabolic androgenic steroids. They are prohibited in both equine and human sports and there have been several cases of SARMs findings reported over the last few years. The aim of this study was to investigate the metabolite profile of the SARM ACP-105 (2-chloro-4-[(3-endo)-3-hydroxy-3-methyl-8-azabicyclo[3.2.1]oct-8-yl]-3-methylbenzonitrile) in order to find analytical targets for doping control. Oral administration of ACP-105 was performed in horses, where blood and urine samples were collected over a time period of 96 h. The in vivo samples were compared with five in vitro incubation models encompassing Cunninghamella elegans, microsomes and S9 fractions of both human and equine origin. The analyses were performed using ultra-high performance liquid chromatography coupled to high resolution Q ExactiveTM OrbitrapTM mass spectrometry (UHPLC-HRMS). A total of 21 metabolites were tentatively identified from the in vivo experiments, of which several novel glucuronides were detected in plasma and urine. In hydrolyzed urine, hydroxylated metabolites dominated. The in vitro models yielded several biotransformation products, including a number of monohydroxylated metabolites matching the in vivo results. The suggested analytical target for equine doping control in plasma is a dihydroxylated metabolite with a net loss of two hydrogens. In urine, the suggested targets are two monohydroxylated metabolites after hydrolysis with β-glucuronidase, selected both due to prolongation of the detection time and the availability of reference material from the in vitro models.

Oxidative biotransformation of stemofoline alkaloids

Biotransformations of stemofoline (1a), (2′S)-hydroxystemofoline (2a), (11Z)-1′,2′-didehydrostemofoline (3a) and stemocurtisine (4) were studied through fermentation with Cunninghamella elegans TISTR 3370. Three new stemofoline derivatives; (6 R)-hydroxystemofoline (1b), (2′S, 6 R)-dihydroxystemofoline (2b) and (11Z,6R)-1′,2′-didehydro-6-hydroxystemofoline (3b), together with the known compound 1′,2′-didehydrostemofoline-N-oxide (3c), were produced by C-hydroxylation and N-oxidation reactions. Stemocurtisine was not biotransformed under these conditions. The transformed product 1b was four times more potent (IC50 = 11.01 ± 1.49 µM) than its precursor 1a (IC50 = 45.1 ± 5.46 µM) as an inhibitor against acetylcholinesterase.

Monitoring metabolism of synthetic cannabinoid 4F-MDMB-BINACA via high-resolution mass spectrometry assessed in cultured hepatoma cell line, fungus, liver microsomes and confirmed using urine samples

PurposeA tert-leucinate derivative synthetic cannabinoid, methyl (2S)-2-([1-(4-fluorobutyl)-1H-indazole-3-carbonyl]amino)-3,3-dimethylbutanoate (4F-MDMB-BINACA, 4F-MDMB-BUTINACA or 4F-ADB) is known to adversely impact health. This study aimed to evaluate the suitability of three different modes of monitoring metabolism: HepG2 liver cells, fungus Cunninghamella elegans (C. elegans) and pooled human liver microsomes (HLM) for comparison with human in-vivo metabolism in identifying suitable urinary marker(s) for 4F-MDMB-BINACA intake.MethodsTentative structure elucidation of in-vitro metabolites was performed on HepG2, C. elegans and HLM using liquid chromatography–tandem mass spectrometry and high-resolution mass spectrometry analysis. In-vivo metabolites obtained from twenty authentic human urine samples were analysed using liquid chromatography–Orbitrap mass spectrometry.ResultsIncubation with HepG2, C. elegans and HLM yielded nine, twenty-three and seventeen metabolites of 4F-MDMB-BINACA, respectively, formed via ester hydrolysis, hydroxylation, carboxylation, dehydrogenation, oxidative defluorination, carbonylation or reaction combinations. Phase II metabolites of glucosidation and sulfation were also exclusively identified using C. elegans model. Eight in-vivo metabolites tentatively identified were mainly products of ester hydrolysis with or without additional dehydrogenation, N-dealkylation, monohydroxylation and oxidative defluorination with further oxidation to butanoic acid. Metabolites with intact terminal methyl ester moiety, i.e., oxidative defluorination with further oxidation to butanoic acid, were also tentatively identified.ConclusionsThe in-vitro models presented proved useful in the exhaustive metabolism studies. Despite limitations, HepG2 identified the major 4F-MDMB-BINACA ester hydrolysis metabolite, and C. elegans demonstrated the capacity to produce a wide variety of metabolites. Both C. elegans and HLM produced all the in-vivo metabolites. Ester hydrolysis and ester hydrolysis plus dehydrogenation 4F-MDMB-BINACA metabolites were recommended as urinary markers for 4F-MDMB-BINACA intake.

Drug biotransformation process favored by fungal biofilms formed on a proposed fixed bed‐airlift hybrid reactor

AbstractBACKGROUNDFungi have the great ability to biotransform drugs, making it possible to direct their application to obtaining new molecules. Our group developed a hybrid fixed bed‐airlift reactor (FB‐ALR) model that allows the formation of Cunninghamella elegans (or other fungi) biofilm and biotransformation of diclofenac (DCF).RESULTSHydrodynamic and rheological parameters [(mixing time (tM), linear gas velocity (UG), liquid linear velocity (UL), gas hold‐up (εG), viscosity (v)], mass transfer (kLa) and biomass formation were superior than those obtained in conventional airlift reactor (ALR) and bubble column reactor. The higher performance of FB‐ALR is a result of the improvement in the oxygenation process, in addition to the reticulate baffle used by the fungus as a support for adhesion and proliferation as biofilm. The formation of fungal biofilms, in addition to reducing the viscosity of the system, favored the retention of DCF, thus facilitating the processes of biotransformation. High‐performance liquid chromatography analyses confirmed such theory.CONCLUSIONFungal biofilms present considerable biotransforming activity, making FB‐ALR the highest yielding biotransformation system amongst those tested herein. © 2020 Society of Chemical Industry (SCI)

3-Hydroxytyrosol regulates biofilm growth in Cunninghamella elegans

In contrast to yeast biofilms, those of filamentous fungi are relatively poorly understood, in particular with respect to their regulation. Cunninghamella elegans is a filamentous fungus that is of biotechnological interest as it catabolises drugs and other xenobiotics in an analogous manner to animals; furthermore, it can grow as a biofilm enabling repeated batch biotransformations. Precisely how the fungus switches from planktonic to biofilm growth is unknown and the aim of this study was to shed light on the possible mechanism of biofilm regulation. In dimorphic yeasts, alcohols such as tyrosol and 2-phenylethanol are known to control the yeast-to-hypha switch, and a similar molecule might be involved in regulating biofilm in C. elegans. Gas chromatography-mass spectrometry analysis of crude ethyl acetate extracts from supernatants of 72 h planktonic and biofilm cultures revealed 3-hydroxytyrosol as a prominent metabolite. Further quantification revealed that the amounts of the compound in planktonic cultures were substantially higher (>10-fold) than in biofilm cultures. In the presence of exogenous 3-hydroxytyrosol the growth of aerial mycelium was inhibited, and there was selective inhibition of biofilm when it was added to culture medium. There was no biotransformation of the compound when it was added to 72 h-old cultures, in contrast to the related compounds tyrosol and 2-phenylethanol, which were oxidised to a number of products. Therefore, we propose that 3-hydroxytyrosol is a new signalling molecule in fungi, which regulates biofilm growth.

Medroxyprogesterone derivatives from microbial transformation as anti-proliferative agents and acetylcholineterase inhibitors (combined in vitro and in silico approaches)

The fungal transformations of medroxyrogesterone (1) were investigated for the first time using Cunninghamella elegans, Trichothecium roseum, and Mucor plumbeus. The metabolites obtained are as following: 6β, 20-dihydroxymedroxyprogesterone (2), 12β-hydroxymedroxyprogesterone (3), 6β, 11β-dihydroxymedroxyprogesterone (4), 16β-hydroxymedroxyprogesterone (5), 11α, 17-dihydroxy-6α-methylpregn-4-ene-3, 20-dione (6), 11-oxo-medroxyprogesterone (7), 6α-methyl-17α-hydroxypregn-1,4-diene-3,20-dione (8), and 6β-hydroxymedroxyprogesterone (9), 15β-hydroxymedroxyprogesterone (10), 6α-methyl-17α, 11β-dihydroxy-5α-pregnan-3, 20-dione (11), 11β-hydroxymedroxyprogesterone (12), and 11α, 20-dihydroxymedroxyprogesterone (13). Among all the microbial transformed products, the newly isolated biotransformed product 13 showed the most potent activity against proliferation of SH-SY5Y cells. Compounds 12, 5, 6, 9, 11, and 3 (in descending order of activity) also showed some extent of activity against SH-SY5Y tumour cell line. The never been reported biotransformed product, 2, showed the most potent inhibitory activity against acetylcholinesterase. Molecular modelling studies were carried out to understand the observed experimental activities, and also to obtain more information on the binding mode and the interactions between the biotransformed products, and enzyme.

The oxygenated products of cryptotanshinone by biotransformation with Cunninghamella elegans exerting anti-neuroinflammatory effects by inhibiting TLR 4-mediated MAPK signaling pathway

Cryptotanshinone (1), a major bioactive constituent in the traditional Chinese medicinal herb Dan-Shen Salvia miltiorrhiza Bunge, has been reported to possess remarkable pharmacological activities. To improve its bioactivities and physicochemical properties, in the present study, cryptotanshinone (1) was biotransformed with the fungus Cunninghamella elegans AS3.2028. Three oxygenated products (2–4) at C-3 of cryptotanshinone (1) were obtained, among them 2 was a new compound. Their structures were elucidated by comprehensive spectroscopic analysis including HRESIMS, NMR and ECD data. All of the biotransformation products (2–4) were found to inhibit significantly lipopolysaccharide-induced nitric oxide production in BV2 microglia cells with the IC50 values of 0.16–1.16 μM, approximately 2–20 folds stronger than the substrate (1). These biotransformation products also displayed remarkably improved inhibitory effects on the production of inflammatory cytokines (IL-1β, IL-6, TNF-α, COX-2 and iNOS) in BV-2 cells via targeting TLR4 compared to substrate (1). The underlying mechanism of 2 was elucidated by comparative transcriptome analysis, which suggested that it reduced neuroinflammatory mainly through mitogen-activated protein kinase (MAPK) signaling pathway. Western blotting results revealed that 2 downregulated LPS-induced phosphorylation of JNK, ERK, and p38 in MAPK signaling pathway. These findings provide a basal material for the discovery of candidates in treating Alzheimer's disease.

Rifampicin: biotransformation study using the fungus Cunninghamella elegans and monitoring through UHPLC-MS

Drug biotransformation studies appear as an alternative to pharmacological investigations of metabolites, development of new drug candidates with reduced investment and most efficient production. The objective of this study was to evaluate the capacity of biotransformation of Rifampicin (RIF) by the filamentous fungus Cunninghamella elegans as a microbial model of mammalian metabolism. In 120 h, C. elegans transformed the drug into the following two metabolites: rifampicin quinone and novel metabolite. The products of rifampicin formed in vitro were monitored by HPLC-PDA, being identified through UHPLC–QTOF/MS. Metabolites were characterized according to their chromatographic profile, mass fragments and UV spectral data. The major metabolic pathways of rifampicin transformed by the fungus were oxidation, demethylation and mono-oxidation. The microbial transformation of RIF showed the potential of Cunninghamella species to produce RIF metabolites. This process can be used for a cost effective method for both known and unknown metabolite production.

Biotransformation of contraceptive drug desogestrel with Cunninghamella elegans, and anti-inflammatory activity of its metabolites

Biotransformation of an orally active contraceptive drug, desogestrel (1), with Cunninghamella elegans yielded a new metabolite, 13β-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-17β-ol-3,6-dione (2), along with five known metabolites, i.e., 13β-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-3β,6β,17β-triol (3), 13β-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-6β,17β-diol-3-one (4), 13β-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-17β-ol-3-one (5), 13β-ethyl-11-epoxy-18,19-dinor-17α-pregn-4-en-20-yn-17β-ol-3-one (6), and 13β-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-10β,17β-diol-3-one (7). The structure of new metabolite 2 was elucidated by using 1H-, 13C-, and 2D-NMR, EI-, and HREI-MS, IR, and UV spectroscopic data. Compounds 1–7 were evaluated for anti-inflammatory activities, i.e., inhibition of T-cell proliferation, and pro-inflammatory cytokine (TNF-α). Compounds 1 (IC50 = 1.12 ± 0.03 µg/mL), 2 (IC50 = 1.15 ± 0.05 µg/mL), 3 (IC50 = 1.15 ± 0.05 µg/mL), 4 (IC50 = 1.40 ± 0.03 µg/mL), 5 (IC50 = 1.78 ± 0.08 µg/mL), and 6 (IC50 = 1.36 ± 0.07 µg/mL) were identified as potent inhibitors of T-cells proliferation, in comparison to the standard drug, prednisolone (IC50 = 3.51 ± 0.03 µg/mL). Compound 7 (IC50 = 6.18 ± 0.04 µg/mL) showed a good activity. In addition, substrate 1 (IC50 ≤ 1 µg/mL), and its metabolites 2 (IC50 = 4.1 ± 0.60 µg/mL), and 6 (IC50 = 6.8 ± 0.8 µg/mL) also showed a potent inhibition of pro-inflammatory cytokine (TNF-α) production, as compared to the standards drug, pentoxifilline (IC50 = 94.8 ± 2.1 µg/mL). Whereas compounds 3 (IC50 = 57.9 ± 7.6 µg/mL), and 5 (IC50 = 27.2 ± 6.8 µg/mL) showed a moderate inhibition of TNF-α production, while compounds 4 and 7 showed no inhibition. Compounds 1–7 were found to be non-cytotoxic to 3T3 normal cell line (mouse fibroblast).

Agroindustrial waste as ecofriendly and low-cost alternative to production of chitosan from Mucorales fungi and antagonist effect against Fusarium solani (Mart.) Sacco and Scytalidium lignicola Pesante

This study aimed to evaluate the production of fungal chitosan (FuChi) from Mucorales fungi cultivated in a cashew apple juice (CAJ) and cheese whey (CW) mixture, and to determine the growth-inhibitory effect of this biopolymer against Fusarium solani CFF109 and Scytalidium lignicola CMM1098, which cause root rot disease in cassava plants. Cunninghamella phaeospora UCP 1303 and Cunninghamella elegans UCP 1306 showed the highest FuChi production in screening assay, being selected to a CCRD 22 design to analyze the influence of different CAJ and CW concentrations in the increase of FuChi production. All nine Mucorales fungi cultivated in CAJ-CW medium, showing FuChi production in the range of 27.58 (Mucor hiemalis UCP 1309) to 65.40 mg/g (C. elegans UCP 1306). During CCRD 22 design, the highest FuChi production (64.09 mg/g) was achieved by C. elegans UCP 1306 cultivated in medium containing 40% (v/v) of CAJ and 30% (v/v) of CW, presenting 75% deacetylation degree and crystallinity indexes of 41.50%. FuChi at 16000 μg/mL showed a better inhibition against S. lignicola mycelial growth (81.70%) when compared with F. solani (22.13%) and induced alterations in hyphae morphology on both strains. CAJ and CW are promising substrates for FuChi production, and this biopolymer shows antimicrobial effect against F. solani and S. lignicola.

Benefits of microbial fertilizer in interspecific interaction with textile sludges on cowpea in a Brazilian Ultisol and on wastes toxicity

Abstract The lack of knowledge of the effects of jean textile sludge on microbial communities, plant growth and nutrition in tropical soils represents an important problem for using organic wastes for sustainable agriculture. The microbial fertilizer is produced from P and K in rocks plus sulfur with Acidithiobacillus bacteria, mixed with organic matter inoculated with selected diazotrophic bacteria (Beijerinckia indica) and Cunninghamella elegans, a fungus that contains chitosan and that may be an alternative to conventional fertilizers. The microbial fertilizer was applied in three doses and was compared with conventional soluble fertilizers, and the interactions with various textile sludges were observed. A greenhouse experiment was conducted as a factorial scheme (4x3) in a randomized block design, with 4 replicates. Multivariate analysis was used to identify the effects of the treatments on the environment, especially with respect to heavy metals. The microbial fertilizer showed similar effects compared to the conventional soluble fertilizers. The jean textile sludge provides positive effects when applied to cowpeas growing in a Brazilian Ultisol. We conclude that the microbial fertilizer improves the plant characteristics and may be a viable alternative to conventional fertilizer. Associated with the jean textile sludges, the microbial fertilizer promotes great effectiveness in the plant characteristics and provides positive results for sustainable agriculture.

Isolation, Identification, and Preserval of Filamentous Fungi Found at Soils of Viotá, Cundinamarca

Objectives: This study focuses on the isolation, identification, and conservation of strains of filamentous fungi recovered from soils of Viota, Cundinamarca; and the subsequent conformation of a strain collection. Methods: An adaptation of the sampling method proposed by Arias and Pineros was carried out. Identification was carried out by macroscopic, microscopic, and DNA sequencing. Conservation techniques were evaluated based on the index of effectiveness of the behavior of viability, purity, and morphological stability. An ANOVA TUKEY test was performed using both an alpha value of α = 0.05 with 95% confidence to assess significant differences.Results: Of the 125 samples analyzed, 165 isolates were recovered, and nine species were identified: Trichoderma spirale 15.53%; Trichoderma ovalisporum 13.66%; Hypocrea nigricans 13.04%; Penicillium implicatum 13.04%; Penicillium citrinum 11.80%; Fusarium incarnatum 11.18%; Fusarium verticiloides 9.94%; Cunninghamella elegans 6.83%, and Aspergillus cf. versicolor 4.97% that had the lowest number of isolates. Aspergillus, Penicillium, Trichoderma, Fusarium, and Cunninghamela are among the most common genera isolated soils. The most efficient conservation method was cryopreservation, with an efficiency rate of 100%. However, although the cultivation technique had an efficiency percentage of 70%, it is considered that it can be used in collections with limited financial support or as a backup preservation method. Angel, in 2006 supports the use of serial cultivation for periods of time such as those handled in this study (15 days). Application/Improvements: The results obtained will contribute to the knowledge of the diversity of this group and its biotic potentials; for the generation of strategies that promote the development of this region. Keywords: Conservation, Isolation, Identification, Filamentous Fungi, Soils.

Whole-cell fungal-mediated structural transformation of anabolic drug metenolone acetate into potent anti-inflammatory metabolites

Seven new derivatives, 6α-hydroxy-1-methyl-3-oxo-5α-androst-1-en-17-yl acetate (2), 6α,17β-dihydroxy-1-methyl-3-oxo-5α-androst-1-en (3), 7β-hydroxy-1-methyl-3-oxo-5α-androst-1-en-17-yl acetate (4), 15β,20-dihydroxy-1-methyl-3-oxo-5α-androst-1-en-17-yl acetate (5), 15β-hydroxy-1-methyl-3-oxo-5α-androst-1-en-17-yl acetate (6), 12β,17β-dihydroxy-1-methyl-3-oxoandrosta-1,4-dien (11), and 7β,15β,17β-trihydroxy-1-methyl-3-oxo-5α-androst-1-en (14), along with six known metabolites, 17β-hydroxy-1-methyl-3-oxoandrosta-1,4-dien (7), 17β-hydroxy-1-methyl-3-oxo-5α-androst-1-en (8), 17β-hydroxy-1-methyl-3-oxo-5β-androst-1-en (9), 1-methyl-5β-androst-1-en-3,17-dione (10), 1-methyl-3-oxoandrosta-1,4-dien-3,17-dione (12), and 17β-hydroxy-1α-methyl-5α-androstan-3-one (13) of metenolone acetate (1), were synthesized through whole-cell biocatalysis with Rhizopus stolonifer, Aspergillus alliaceous, Fusarium lini, and Cunninghamella elegans. Atamestane (12), an aromatase inhibitor, was synthesized for the first time via F. lini-mediated transformation of 1 as the major product. Hydroxylation, dehydrogenation, and reduction were occurred during biocatalysis. Study indicated that F. lini was able to catalyze dehydrogenation reactions selectively. Structures of compounds 1–14 were determined through NMR, HRFAB-MS, and IR spectroscopic data. Compounds 1–14 were identified as non-cytotoxic against BJ human fibroblast cell line (ATCC CRL-2522). Metabolite 5 (81.0 ± 2.5%) showed a potent activity against TNF-α production, as compared to the substrate 1 (62.5 ± 4.4%). Metabolites 2 (73.4 ± 0.6%), 8 (69.7 ± 1.4%), 10 (73.2 ± 0.3%), 11 (60.1 ± 3.3%), and 12 (71.0 ± 7.2%), also showed a good inhibition of TNF-α production. Compounds 3 (IC50 = 4.4 ± 0.01 µg/mL), and 5 (IC50 = 10.2 ± 0.01 µg/mL) showed a significant activity against T-cell proliferation. Identification of selective inhibitors of TNF-α production, and T-cell proliferation is a step forward towards the development of anti-inflammatory drugs.

Metabolism of insecticide diazinon by Cunninghamella elegans ATCC36112.

The fungal metabolism of diazinon was investigated and the microbial model (Cunninghamella elegans ATCC36112) could effectively degrade the organophosphorus pesticide (diazinon) mediated by cytochrome P450, which was mainly involved in oxidation and hydrolysis of phase I metabolism. Approximately 89% of diazinon was removed within 7 days and was not observed after 13 days with concomitant accumulation of eight metabolites. Structures of the metabolites were fully or tentatively identified with GC-MS and 1H, 13C NMR. The major metabolites of diazinon were diethyl (2-isopropyl-6-methylpyrimidin-4-yl) phosphate (diazoxon) and 2-isopropyl-6-methyl-4-pyrimidinol (pyrimidinol), and formation of minor metabolites was primarily the result of hydroxylation. To determine the responsible enzymes in diazinon metabolism, piperonyl butoxide and methimazole were treated, and the kinetic responses of diazinon and its metabolites by Cunninghamella elegans were measured. Results indirectly demonstrated that cytochrome P450 and flavin monooxygenase were involved in the metabolism of diazinon, but methimazole inhibited the metabolism less effectively. Based on the metabolic profiling, a possible metabolic pathway involved in phase I metabolism of diazinon was proposed, which would contribute to providing insight into understanding the toxicological effects of diazinon and the potential application of fungi on organophosphorus pesticides.

Acid Oxidation of Muskmelon Fruit for the Fabrication of Carbon Dots with Specific Emission Colors for Recognition of Hg2+ Ions and Cell Imaging.

In this study, water-soluble emissive carbon dots (CDs) are effectively fabricated with specific optical properties and colors by acid oxidation of muskmelon (Cucumis melo) fruit, which are termed as C. melo CDs (CMCDs). The fluorescence properties of CMCDs were tuned by controlling the experimental conditions that allow them to emit different colors, that is, blue (B-), green (G-), and yellow (Y-) CMCDs, with different emission wavelengths at 432, 515, and 554 nm when excited at 342, 415, and 425 nm, respectively. The fabricated multicolor-emissive CDs were confirmed by various analytical techniques. The sizes of B-, G-, and Y-CMCDs were found to be ∼3.5, ∼4.3, and ∼5.8 nm, respectively. The as-prepared CMCDs display stable emissions with quantum yields of 7.07, 26.9, and 14.3% for the three CMCDs, which could act as a promising probe for the selective detection of Hg2+ ions. Upon the addition of Hg2+ ions, the fluorescence intensity of G-CMCDs at 515 nm was quenched largely than that of B- and Y-CMCDs. The spectroscopic results display that the G-CMCDs acted as a sensor for the detection of Hg2+ ions with a wide linear range from 1.0 to 25 μM (R2 = 0.9855) with a detection limit of 0.33 μM. This method was successfully applied to detect Hg2+ ions in biological and water samples. The fabricated multicolor-emissive CMCDs possess the cell (Cunninghamella elegans, Aspergillus flavus, and Rhizoctonia solani) imaging property, suggesting the biocompatible nature for multicolor imaging of various cells.

Evaluation of Microbial Transformation of 10-deoxoartemisinin by UPLC-ESI-Q-TOF-MSE.

10-deoxoartemisinin is a semisynthetic derivative of artemisinin that lacks a lactone carbonyl group at the 10-position, and has stronger antimalarial properties than artemisinin. However, 10-deoxoartemisinin has limited utility as a therapeutic agent because of its low solubility and bioavailability. Hydroxylated 10-deoxoartemisinins are a series of properties-improved derivatives. Via microbial transformation, which can hydroxylate 10-deoxoartemisinin at multiple sites, the biotransformation products of 10-deoxoartemisinin have been investigated in this paper. Using ultra-performance liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MSE) combined with UNIFI software, products of microbial transformation of 10-deoxoartemisinin were rapidly and directly analyzed. The hydroxylation abilities of nine microorganisms were compared using this method. All of the microorganisms evaluated were able to hydroxylate 10-deoxoartemisinin, and a total of 35 hydroxylated products were identified. These can be grouped into dihydroxylated 10-deoxoartemisinins, monohydroxylated 10-deoxoartemisinins, hydroxylated dehydrogenated 10-deoxoartemisinins, and hydroxylated hydrogenated 10-deoxoartemisinins. Cunninghamella echinulata and Cunninghamella blakesleeana are able to hydroxylate 10-deoxoartemisinin, and their biotransformation products are investigated here for the first time. Cunninghamella elegans CICC 40250 was shown to most efficiently hydroxylate 10-deoxoartemisinin, and could serve as a model organism for microbial transformation. This method could be used to generate additional hydroxylated 10-deoxoartemisinins for further research.

Mapping the Biotransformation of Coumarins through Filamentous Fungi

Natural coumarins are present in remarkable amounts as secondary metabolites in edible and medicinal plants, where they display interesting bioactivities. Considering the wide enzymatic arsenal of filamentous fungi, studies on the biotransformation of coumarins using these microorganisms have great importance in green chemical derivatization. Several reports on the biotransformation of coumarins using fungi have highlighted the achievement of chemical analogs with high selectivity by using mild and ecofriendly conditions. Prompted by the enormous pharmacological, alimentary, and chemical interest in coumarin-like compounds, this study evaluated the biotransformation of nine coumarin scaffolds using Cunninghamella elegans ATCC 10028b and Aspergillus brasiliensis ATCC 16404. The chemical reactions which were catalyzed by the microorganisms were highly selective. Among the nine studied coumarins, only two of them were biotransformed. One of the coumarins, 7-hydroxy-2,3-dihydrocyclopenta[c]chromen-4(1H)-one, was biotransformed into the new 7,9-dihydroxy-2,3-dihydrocyclopenta[c]chromen-4(1H)-one, which was generated by selective hydroxylation in an unactivated carbon. Our results highlight some chemical features of coumarin cores that are important to biotransformation using filamentous fungi.

BIOTRANSFORMATION OF METRONIDAZOLE BY CUNNINGHAMELLA ELEGANS ATCC 9245

Drug biotransformation studies appear as an alternative to pharmacological studies of metabolites, development of new drug candidates with reduced investment as well as the most efficient production of chemical structures involves and drug quality control studies. A wide range of reactions in biotransformations process is catalyzed by microorganisms. Fungi can be considered as a promising source of new biotransformation reactions. The aim of this study was to evaluate the capacity of metronidazole biotransformation through the filamentous fungus Cunninghamella elegans ATCC 9245. The monitoring of metabolite formation was performed by high-performance liquid chromatography (HPLC) coupled to ultraviolet (UV) spectrophotometry. The results of the biotransformation of metronidazole showed drug consumption in culture and the formation of four new chromatographic peaks of chemical structures not elucidated. The method showed it became linear over 10-70 μg/mL (r = 0.999953). Accuracy, precision and stability studies agree with international guidelines. Results are consistent in accordance with the principles of green chemistry as the experimental conditions had a low environmental impact, and few solvents use.