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Pathogenicity of Aschersonia spp. against whiteflies Bemisia argentifolii and Trialeurodes vaporariorum

Meekes ET, Fransen JJ, van Lenteren JC

J Invertebr Pathol, 2002 Sep;81(1):1-11.
PMID: 12417207

Entomopathogenic fungi of the genus Aschersonia are specific for whitefly and scale insects. They can be used as biological control agents against silverleaf whitefly, Bemisia argentifolii and greenhouse whitefly, Trialeurodes vaporariorum. Forty-four isolates of Aschersonia spp. were tested for their ability to sporulate and germinate on semi-artificial media and to infect insect hosts. Seven isolates sporulated poorly (less than 1x10(7) conidia/dry weight) and 10 were not able to infect either of the whitefly species. Several isolates were able to produce capilliconidia. Infection level was not correlated with germination on water agar. After a selection based on spore production and infection, virulence of 31 isolates was evaluated on third instar nymphs of both whitefly species on poinsettia (Euphorbia pulcherrima). Whitefly infection levels varied between 2 and 70%, and infection percentages of B. argentifolii correlated with that of T. vaporariorum. However, mortality was higher for T. vaporariorum than for B. argentifolii, as a result of a higher 'mortality due to unknown causes.' Several isolates, among which unidentified species of Aschersonia originating from Thailand and Malaysia, A. aleyrodis from Colombia, and A. placenta from India showed high spore production on semi-artificial medium and high infection levels of both whitefly species.

Matched MeSH terms: Mitosporic Fungi/pathogenicity*
A metagenome for lacustrine Cladophora (Cladophorales) reveals remarkable diversity of eukaryotic epibionts and genes relevant to materials cycling

Graham LE, Knack JJ, Graham ME, Graham JM, Zulkifly S

J Phycol, 2015 Jun;51(3):408-18.
PMID: 26986658 DOI: 10.1111/jpy.12296

Periphyton dominated by the cellulose-rich filamentous green alga Cladophora forms conspicuous growths along rocky marine and freshwater shorelines worldwide, providing habitat for diverse epibionts. Bacterial epibionts have been inferred to display diverse functions of biogeochemical significance: N-fixation and other redox reactions, phosphorus accumulation, and organic degradation. Here, we report taxonomic diversity of eukaryotic and prokaryotic epibionts and diversity of genes associated with materials cycling in a Cladophora metagenome sampled from Lake Mendota, Dane Co., WI, USA, during the growing season of 2012. A total of 1,060 distinct 16S, 173 18S, and 351 28S rRNA operational taxonomic units, from which >220 genera or species of bacteria (~60), protists (~80), fungi (6), and microscopic metazoa (~80), were distinguished with the use of reference databases. We inferred the presence of several algal taxa generally associated with marine systems and detected Jaoa, a freshwater periphytic ulvophyte previously thought endemic to China. We identified six distinct nifH gene sequences marking nitrogen fixation, >25 bacterial and eukaryotic cellulases relevant to sedimentary C-cycling and technological applications, and genes encoding enzymes in aerobic and anaerobic pathways for vitamin B12 biosynthesis. These results emphasize the importance of Cladophora in providing habitat for microscopic metazoa, fungi, protists, and bacteria that are often inconspicuous, yet play important roles in ecosystem biogeochemistry.

Matched MeSH terms: Fungi
Ameliorative effect of Albizia chinensis synthesized ZnO-NPs on Mycoplasma pneumoniae infected pneumonia mice model

Yu L, Lu M, Zhang W, Alarfaj AA, Hirad AH, Zhang H

Microb Pathog, 2020 Apr;141:103960.
PMID: 31953224 DOI: 10.1016/j.micpath.2019.103960

BACKGROUND: Mycoplasma pneumoniae (MP) is a common cause of community-acquired pneumonia (CAP) among the children and adults that results upper and lower respiratory tract infections.
OBJECTIVE: This study was aimed to inspect the ameliorative action of A. chinensis synthesized ZnONPs against M. pneumoniae infected pneumonia mice model.
MATERIALS AND METHODS: ZnO NPs was synthesized from Albizia chinensis bark extract and characterized by UV-Vis spectroscopy, Fourier Transform Infrared (FTIR), Transmission Electron Microscopy (TEM), energy dispersive X-ray (EDX) and atomic force microscope (AFM) analyses. The antibacterial effectual of synthesized ZnONPs were examined against clinical pathogens. The pneumonia was induced to BALB/c mice via injecting the M. pneumoniae and treated with synthesized ZnONPs, followed by the total protein content, total cell counts and inflammatory mediators level was assessed in the BALF of experimental animals. The Histopathological investigation was done in the lung tissues of test animals.
RESULTS: The outcomes of this work revealed that the formulated ZnONPs was quasi-spherical, radial and cylindrical; the size was identified as 116.5 ± 27.45 nm in diameter. The in vitro antimicrobial potential of formulated ZnO-NPs displayed noticeable inhibitory capacity against the tested fungal and bacterial strains. The administration of synthesized ZnO-NPs in MP infected mice model has significantly reduced the levels of total protein, inflammatory cells, inflammatory cytokines such as IL-1, IL-6, IL-8, tumour necrosis factor-alpha (TNF-a) and transforming growth factor (TGF). Besides, the histopathological examination of MP infected mice lung tissue showed the cellular arrangements were effectively retained after administration of synthesized ZnO-NPs.
CONCLUSION: In conclusion, synthesized ZnO-NPs alleviate pneumonia progression via reducing the level of inflammatory cytokines and inflammatory cells in MP infected mice model.

Matched MeSH terms: Fungi/drug effects
Fulltext Potential Antiviral Agents from Marine Fungi: An Overview

Moghadamtousi SZ, Nikzad S, Kadir HA, Abubakar S, Zandi K

Mar Drugs, 2015 Jul;13(7):4520-38.
PMID: 26204947 DOI: 10.3390/md13074520

Biodiversity of the marine world is only partially subjected to detailed scientific scrutiny in comparison to terrestrial life. Life in the marine world depends heavily on marine fungi scavenging the oceans of lifeless plants and animals and entering them into the nutrient cycle by. Approximately 150 to 200 new compounds, including alkaloids, sesquiterpenes, polyketides, and aromatic compounds, are identified from marine fungi annually. In recent years, numerous investigations demonstrated the tremendous potential of marine fungi as a promising source to develop new antivirals against different important viruses, including herpes simplex viruses, the human immunodeficiency virus, and the influenza virus. Various genera of marine fungi such as Aspergillus, Penicillium, Cladosporium, and Fusarium were subjected to compound isolation and antiviral studies, which led to an illustration of the strong antiviral activity of a variety of marine fungi-derived compounds. The present review strives to summarize all available knowledge on active compounds isolated from marine fungi with antiviral activity.

Matched MeSH terms: Fungi/chemistry*
Morphological characteristics and pathogenicity of fungi associated with Roselle (Hibiscus Sabdariffa) diseases in Penang, Malaysia

Eslaminejad T, Zakaria M

Microb Pathog, 2011 Nov;51(5):325-37.
PMID: 21839160 DOI: 10.1016/j.micpath.2011.07.007

Roselle, or Jamaica sorrel (Hibiscus sabdariffa) is a popular vegetable in many tropical regions, cultivated for its leaves, seeds, stems and calyces which, the dried calyces are used to prepare tea, syrup, jams and jellies and as beverages. The main objectives of this study were to identify and characterise fungal pathogens associated with Roselle diseases based on their morphological and cultural characteristics and to determine the pathogenicity of four fungi infecting Roselle seedlings, namely Phoma exigua, Fusarium nygamai, Fusarium tgcq and Rhizoctonia solani in Penang. A total of 200 fungal isolates were obtained from 90 samples of symptomatic Roselle tissues. The isolates were identified based on cultural and morphological characteristics, as well as their pathogenicity. The fungal pathogen most frequently isolated was P. exigua (present in 45% of the samples), followed by F. nygamai (25%), Rhizoctonia solani (19%) and F. camptoceras (11%). Pathogenicity tests showed that P. exigua, F. nygamai, F. camptoceras and R. solani were able to infect both wounded and unwounded seedlings with different degrees of severity as indicated by the Disease severity (DS). R. solani was the most pathogenic fungus affecting both wounded and unwounded Roselle seedlings, followed by P. exigua that was highly pathogenic on wounded seedlings. F. nygamai was less pathogenic while the least pathogenic fungus was F. camptoceras, infecting only the unwounded seedlings but, surprisingly, not the wounded plants.

Matched MeSH terms: Fungi/classification; Fungi/growth & development*; Fungi/isolation & purification; Fungi/pathogenicity*
Fulltext Fusarium Species in Mangrove Soil in Northern Peninsular Malaysia and the Soil Physico-Chemical Properties

Mohamed Zubi WS, Mohd MH, Mohamed Nor NMI, Zakaria L

Microorganisms, 2021 Feb 26;9(3).
PMID: 33652900 DOI: 10.3390/microorganisms9030497

Fusarium genus comprises important saprophytic and phytopathogenic fungi and is widespread in nature. The present study reports the occurrence of Fusarium spp. in soils from two mangrove forests in northern Peninsular Malaysia and analyzed physico-chemical properties of the mangrove soil. Based on TEF-1α sequences, nine Fusarium species were identified: Fusarium solani species complex (FSSC) (n = 77), Fusarium verticillioides (n = 20), Fusarium incarnatum (n = 10), Fusarium proliferatum (n = 7), Fusarium lateritium (n = 4), Fusarium oxysporum (n = 3), Fusarium rigidiuscula (n = 2), Fusarium chlamydosporum (n = 1), and Fusarium camptoceras (n = 1); FSSC isolates were the most prevalent. Phylogenetic analysis of the combined TEF-1α and ITS sequences revealed diverse phylogenetic affinities among the FSSC isolates and potentially new phylogenetic clades of FSSC. Soil analysis showed varied carbon content, pH, soil moisture, and salinity, but not nitrogen content, between sampling locations. Regardless of the physico-chemical properties, various Fusarium species were recovered from the mangrove soils. These were likely saprophytes; however, some were well-known plant pathogens and opportunistic human pathogens. Thus, mangrove soils might serve as inoculum sources for plant and human pathogenic Fusarium species. The present study demonstrates the occurrence of various Fusarium species in the extreme environment of mangrove soil, thereby contributing to the knowledge on species diversity in Fusarium.

Matched MeSH terms: Fungi
Fulltext Molecular identification of endophytic fungi in lawn grass (Axonopus compressus) and their pathogenic ability

Azuddin NF, Mohamad Noor Azmy MS, Zakaria L

Sci Rep, 2023 Mar 14;13(1):4239.
PMID: 36918601 DOI: 10.1038/s41598-023-31291-7

Lawn grass (Axonopus compressus) is a widely distributed grass species from the family Poaceae that is ubiquitous in Malaysia. We isolated endophytic fungi from the leaves of A. compressus and molecularly identified them as Fusarium parceramosum, Colletotrichum siamense, C. gigasporum, C. endophyticum, Curvularia lunata, Stagonospora bicolor, Calonectria gracilis, and Albifimbria verrucari. These fungal endophytes are considered host generalists, as they have been isolated from other plants and have also been reported to be latent plant pathogens. We tested the pathogenicity of selected endophytic fungal isolates on A. compressus leaves, chili (Capsicum annum), and tomato (Solanum lycopersicum), and found that they were pathogenic to wounded A. compressus leaves with low to moderate virulence, and several were pathogenic to wounded and unwounded chili and tomato fruits. This indicated that the endophytes could infect both vegetable fruits with low to very high virulence. Pathogenicity tests demonstrated that endophytic fungi from the leaves of A. compressus can become pathogenic and infect the host and other plant species. The findings also indicated that leaves of A. compressus may harbor pathogens with latent ability that can become active due to changes in environmental conditions, thereby disrupting the balance between host-endophyte antagonism.

Matched MeSH terms: Fungi
Fulltext Aspergillus sydowii strain SCAU066 and aspergillus versicolor isolate BAB-6580: potential source of xylanolytic, cellulolytic and amylolytic enzymes

Nur Syahira Mohammad, Zaidah Zainal Ariffin

Science Letters, 2020;14(2):15-23.
MyJurnal

Fungi is known to produce a wide range of biologically active metabolites and enzymes. Enzymes produced by fungi are utilized in food and pharmaceutical industries because of their rich enzymatic profile. Filamentous fungi are particularly interesting due to their high production of extracellular enzymes which has a large industrial potential. The aim of this study is to isolate potential soil fungi species that are able to produce functional enzymes for industries. Five Aspergillus species were successfully isolated from antibiotic overexposed soil (GPS coordinate of N3.093219 E101.40269) by standard microbiological method. The isolated fungi were identified via morphological observations and molecular tools; polymerase chain reactions, ITS 1 (5’- TCC GTA GGT GAA CCT GCG G3’) forward primer and ITS 4 (5’-TCC TCC GCT TAT TGA TAT GC-3’) reverse primer. The isolated fungi were identified as Aspergillus sydowii strain SCAU066, Aspergillus tamarii isolate TN-7, Aspergillus candidus strain KUFA 0062, Aspergillus versicolor isolate BAB-6580, and Aspergillus protuberus strain KAS 6024. Supernatant obtained via submerged fermentation of the isolated fungi in potato dextrose broth (PDB) and extracted via centrifugation was loaded onto specific media to screen for the production of xylanolytic, cellulolytic and amylolytic enzymes. The present findings indicate that Aspergillus sydowii strain SCAU066 and Aspergillus versicolor isolate BAB-6580 have great potential as an alternative source of xylanolytic, cellulolytic and amylolytic enzymes.

Matched MeSH terms: Fungi
Fulltext Nematophagous fungi as a biological control agent for nematode parasites of small ruminants in Malaysia: a special emphasis on Duddingtonia flagrans

Chandrawathani P, Jamnah O, Waller PJ, Höglund J, Larsen M, Zahari WM

Vet Res, 2002 Nov-Dec;33(6):685-96.
PMID: 12498569

Approximately 2,800 fresh dung samples from animals, mainly ruminant livestock, were screened for the presence of nematophagous fungi in Malaysia. Arthrobotrys spp. was noted on numerous occasions, but only one isolate of Duddingtonia flagrans was made. For the purposes of producing sufficient quantities of this fungus for feeding trials in sheep, various, commonly available, cheap plant materials were tested as possible growth substrates. This showed that cereal grains (wheat, millet and rice) were the best media for fungal growth. Pen feeding trials were carried out using sheep, both naturally and experimentally infected with nematode parasites (predominantely Haemonchus contortus), to test the efficiency of D. flagrans when administered either in a grain supplement, or incorporated into a feed block. These showed that the fungus survived gut passage in sheep and that dose rates of approximately 1 x 10(6) D. flagrans spores / animal / day, reduced the percentage of infective larvae developing in faecal cultures by more than 90%. These results indicate that using D. flagrans as a biological control agent of nematode parasites, is a promising alternative to nematode parasite control of small ruminants in Malaysia, where anthelmintic resistance is now a major problem.

Matched MeSH terms: Mitosporic Fungi/growth & development; Mitosporic Fungi/physiology*
Biological control of nematode parasites of small ruminants in Malaysia using the nematophagous fungus Duddingtonia flagrans

Chandrawathani P, Jamnah O, Waller PJ, Larsen M, Gillespie AT, Zahari WM

Vet Parasitol, 2003 Nov 14;117(3):173-83.
PMID: 14630426

Control of nematode parasites of small ruminants in a wet, tropical environment using the nematophagous fungus, Duddingtonia flagrans, was assessed in this study. Two methods of fungal delivery were tested, namely as a daily feed supplement, or incorporated into feed blocks. Initially, pen trials were conducted with individually penned groups of sheep and goats at dose rates of 125,000 spores and 250,000 spores/kg live weight per day. At the lower dose rate this reduction was between 80 and 90% compared with the pre-treatment levels. At the higher dose rate, there was virtually complete suppression (>99% reduction) of larval recovery. Trials using the fungal feed blocks, showed that when animals were individually penned, they consumed only small amounts of the block (particularly goats), hence little effect on larval recovery in faecal cultures was observed. Grouping animals according to species and dose rate induced satisfactory block consumption and subsequent high levels of larval reduction in faecal cultures. These larval reductions were mirrored by the presence of fungus in faecal cultures. This work was followed by a small paddock trial, whereby three groups of sheep were fed either a feed supplement without fungal spores, supplement with spores, or offered fungal blocks. The dose rate of spores in the latter two groups was 500,000 spores/kg live weight per day. Egg counts were significantly reduced in the two fungal groups, compared with the control group and the latter required two salvage anthelmintic treatments to prevent mortality due to haemonchosis. Pasture larval numbers on the two fungal group plots were also much lower than on the control plot.

Matched MeSH terms: Mitosporic Fungi/growth & development; Mitosporic Fungi/physiology*
Polyancora globosa gen. sp. nov., an aeroaquatic fungus from Malaysian peat swamp forests

Voglmayr H, Yule CM

Mycol. Res., 2006 Oct;110(Pt 10):1242-52.
PMID: 17018253

During an investigation of submerged leaves and twigs sampled from tropical peat swamp forests located in Peninsular Malaysia, an anamorphic fungus not attributable to a described genus was detected and isolated in pure culture. Conidial ontogeny was thoroughly studied and illustrated using both light and SEM, which revealed a unique conidial morphology. Analysis of partial nuLSU rDNA and ITS data revealed a phylogenetic position within the Xylariales (Ascomycota), but family affiliation remained unclear.

Matched MeSH terms: Fungi/classification; Fungi/isolation & purification*
Biodecolorization and biodegradation potential of recalcitrant triphenylmethane dyes by Coriolopsis sp. isolated from compost

Chen SH, Yien Ting AS

J Environ Manage, 2015 Mar 01;150:274-280.
PMID: 25527986 DOI: 10.1016/j.jenvman.2014.09.014

Triphenylmethane dyes (TPM) are recalcitrant colorants brought into the environment. In this study, a lesser-known white rot fungus Coriolopsis sp. (1c3), isolated from compost of Empty Fruit Bunch (EFB) of oil palm, was explored for its decolorization potential of TPM dyes. The isolate 1c3 demonstrated good decolorization efficiencies in the treatment of Crystal Violet (CV; 100 mg l(-1)), Methyl Violet (MV; 100 mg l(-1)) and Cotton Blue (CB; 50 mg(-1)), with 94%, 97% and 91%, within 7, 7 and 1 day(s), respectively. Malachite Green (MG; 100 mg l(-1)) was the most recalcitrant dye, with 52% decolorization after 9 days. Dye removal by 1c3 was presumably via biosorption, whereby the process was determined to be influenced by fungal biomass, initial dye concentrations and oxygen requirements. Biodegradation was also a likely mechanism responsible for dye removal by 1c3, occurred as indicated by the reduction of dye spectra peaks. Detection of laccase, lignin peroxidase and NADH-DCIP reductase activities further substantiate the possible occurrence of biodegradation of TPM dyes by 1c3.

Matched MeSH terms: Fungi/metabolism*
Fulltext Synthesis, PASS-Predication and in Vitro Antimicrobial Activity of Benzyl 4-O-benzoyl-α-l-rhamnopyranoside Derivatives

Matin MM, Nath AR, Saad O, Bhuiyan MM, Kadir FA, Abd Hamid SB, et al.

Int J Mol Sci, 2016 Aug 27;17(9).
PMID: 27618893 DOI: 10.3390/ijms17091412

Benzyl α-l-rhamnopyranoside 4, obtained by both conventional and microwave assisted glycosidation techniques, was subjected to 2,3-O-isopropylidene protection to yield compound 5 which on benzoylation and subsequent deprotection of isopropylidene group gave the desired 4-O-benzoylrhamnopyranoside 7 in reasonable yield. Di-O-acetyl derivative of benzoate 7 was prepared to get newer rhamnopyranoside. The structure activity relationship (SAR) of the designed compounds was performed along with the prediction of activity spectra for substances (PASS) training set. Experimental studies based on antimicrobial activities verified the predictions obtained by the PASS software. Protected rhamnopyranosides 5 and 6 exhibited slight distortion from regular ¹C₄ conformation, probably due to the fusion of pyranose and isopropylidene ring. Synthesized rhamnopyranosides 4-8 were employed as test chemicals for in vitro antimicrobial evaluation against eight human pathogenic bacteria and two fungi. Antimicrobial and SAR study showed that the rhamnopyranosides were prone against fungal organisms as compared to that of the bacterial pathogens. Interestingly, PASS prediction of the rhamnopyranoside derivatives 4-8 were 0.49 < Pa < 0.60 (where Pa is probability 'to be active') as antibacterial and 0.65 < Pa < 0.73 as antifungal activities, which showed significant agreement with experimental data, suggesting rhamnopyranoside derivatives 4-8 were more active against pathogenic fungi as compared to human pathogenic bacteria thus, there is a more than 50% chance that the rhamnopyranoside derivative structures 4-8 have not been reported with antimicrobial activity, making it a possible valuable lead compound.

Matched MeSH terms: Fungi/drug effects
Effects of two acetanilide herbicides on microbial populations and their cellulolytic activities

Sahid IB, Yap MY

Bull Environ Contam Toxicol, 1994 Jan;52(1):61-8.
PMID: 8130418
Matched MeSH terms: Fungi/drug effects; Fungi/enzymology; Fungi/metabolism
Recent pathogen and mosquito host records from Penang Island, Malaysia

Chapman HC, Lacey LA, Yap HH

J Am Mosq Control Assoc, 1987 Jun;3(2):306-8.
PMID: 2904951
Matched MeSH terms: Fungi/isolation & purification
Fulltext Mycomedicine: A Unique Class of Natural Products with Potent Anti-tumour Bioactivities

Dai R, Liu M, Nik Nabil WN, Xi Z, Xu H

Molecules, 2021 Feb 19;26(4).
PMID: 33669877 DOI: 10.3390/molecules26041113

Mycomedicine is a unique class of natural medicine that has been widely used in Asian countries for thousands of years. Modern mycomedicine consists of fruiting bodies, spores, or other tissues of medicinal fungi, as well as bioactive components extracted from them, including polysaccharides and, triterpenoids, etc. Since the discovery of the famous fungal extract, penicillin, by Alexander Fleming in the late 19th century, researchers have realised the significant antibiotic and other medicinal values of fungal extracts. As medicinal fungi and fungal metabolites can induce apoptosis or autophagy, enhance the immune response, and reduce metastatic potential, several types of mushrooms, such as Ganoderma lucidum and Grifola frondosa, have been extensively investigated, and anti-cancer drugs have been developed from their extracts. Although some studies have highlighted the anti-cancer properties of a single, specific mushroom, only limited reviews have summarised diverse medicinal fungi as mycomedicine. In this review, we not only list the structures and functions of pharmaceutically active components isolated from mycomedicine, but also summarise the mechanisms underlying the potent bioactivities of several representative mushrooms in the Kingdom Fungi against various types of tumour.

Matched MeSH terms: Fungi/chemistry*
Fulltext Recent Developments in the Facile Bio-Synthesis of Gold Nanoparticles (AuNPs) and Their Biomedical Applications

Lee KX, Shameli K, Yew YP, Teow SY, Jahangirian H, Rafiee-Moghaddam R, et al.

Int J Nanomedicine, 2020;15:275-300.
PMID: 32021180 DOI: 10.2147/IJN.S233789

Gold nanoparticles (AuNPs) are extensively studied nanoparticles (NPs) and are known to have profound applications in medicine. There are various methods to synthesize AuNPs which are generally categorized into two main types: chemical and physical synthesis. Continuous efforts have been devoted to search for other more environmental-friendly and economical large-scale methods, such as environmentally friendly biological methods known as green synthesis. Green synthesis is especially important to minimize the harmful chemical and toxic by-products during the conventional synthesis of AuNPs. Green materials such as plants, fungi, microorganisms, enzymes and biopolymers are currently used to synthesize various NPs. Biosynthesized AuNPs are generally safer for use in biomedical applications since they come from natural materials themselves. Multiple surface functionalities of AuNPs allow them to be more robust and flexible when combined with different biological assemblies or modifications for enhanced applications. This review focuses on recent developments of green synthesized AuNPs and discusses their numerous biomedical applications. Sources of green materials with successful examples and other key parameters that determine the functionalities of AuNPs are also discussed in this review.

Matched MeSH terms: Fungi/chemistry
Fulltext Antioxidant activity of hispidin oligomers from medicinal fungi: a DFT study

El Hassane A, Shah SA, Hassan NB, El Moussaoui N, Ahmad R, Zulkefeli M, et al.

Molecules, 2014;19(3):3489-507.
PMID: 24662069 DOI: 10.3390/molecules19033489

Hispidin oligomers are styrylpyrone pigments isolated from the medicinal fungi Inonotus xeranticus and Phellinus linteus. They exhibit diverse biological activities and strong free radical scavenging activity. To rationalize the antioxidant activity of a series of four hispidin oligomers and determine the favored mechanism involved in free radical scavenging, DFT calculations were carried out at the B3P86/6-31+G (d, p) level of theory in gas and solvent. The results showed that bond dissociation enthalpies of OH groups of hispidin oligomers (ArOH) and spin density delocalization of related radicals (ArO•) are the appropriate parameters to clarify the differences between the observed antioxidant activities for the four oligomers. The effect of the number of hydroxyl groups and presence of a catechol moiety conjugated to a double bond on the antioxidant activity were determined. Thermodynamic and kinetic studies showed that the PC-ET mechanism is the main mechanism involved in free radical scavenging. The spin density distribution over phenoxyl radicals allows a better understanding of the hispidin oligomers formation.

Matched MeSH terms: Fungi/chemistry*
Diketopiperazine and isoindolinone alkaloids from the endophytic fungus Aspergillus sp. HAB10R12

Al-Khdhairawi AAQ, Loo JSE, Abd Mutalib N, Abd Latip N, Manshoor N, Abu Bakar H, et al.

Phytochemistry, 2023 Jul;211:113685.
PMID: 37088350 DOI: 10.1016/j.phytochem.2023.113685

Four previously undescribed alkaloids, aspergillinine A-D, and four known diterpene pyrones were isolated from the potato dextrose agar (PDA) culture of Aspergillus sp. HAB10R12. The chemical structures of the isolated compounds were elucidated based on a detailed analysis of their NMR and MS data. The absolute configuration of the isolated compounds was determined by Electronic Circular Dichroism analysis coupled with computational methods. Aspergillinine A represents the first example of a diketopiperazine dipeptide containing the unnatural amino acid N-methyl kynurenine. Its absolute configuration revealed that it adopts a rather unusual conformation. Aspergillinine B represents a previously unencountered skeleton containing an isoindolinone ring. Aspergillinine C and D were similar to previously isolated diketopiperazine alkaloids, namely, lumpidin and brevianamide F, respectively. The diterpene pyrones were isolated twice previously, once from a soil-derived Aspergillus species, and once from the liquid culture of Aspergillus sp. HAB10R12. The alkaloids isolated in this study showed no antiproliferative activity when tested against HepG2 and A549 cancer cell lines.

Matched MeSH terms: Fungi/chemistry
Fulltext Imaging features of fungal infection in immuno-suppressed patients in a local ward outbreak

Ahmad Sarji S, Wan Abdullah W, Wastie M

Biomed Imaging Interv J, 2006 Apr;2(2):e21.
PMID: 21614228 DOI: 10.2349/biij.2.2.e21

To examine the role of imaging in diagnosing and assessing fungal infections in paediatric patients undergoing chemotherapy in a facility, which had high fungal air contamination due to adjacent building construction work.

Matched MeSH terms: Fungi

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