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Glossary
Published in Jerry P. Byers, Metalworking Fluids, Third Edition, 2018
mycobacteria: Gram-positive, relatively slow-growing bacteria having a rough, waxy cell wall that is high in mycolic acid content. The cell wall is relatively impermeable to various basic dyes, unless the dyes are combined with phenol. However, once stained, the mycobacteria resist decolorization with acidified organic solvents, giving rise to the description of the organism as being “acid-fast”
Selected fungi of the genus Lactarius - screening of antioxidant capacity, antimicrobial activity, and genotoxicity
Published in Journal of Toxicology and Environmental Health, Part A, 2022
Miroslava Stanković, Violeta Mitić, Vesna Stankov Jovanović, Marija Dimitrijević, Jelena Nikolić, Gordana Stojanović
L. deliciosus was more effective than other Lactarius species against tested microorganisms (Dulger, Yilmaz, and Gucin 2002). According to literature, Jayko et al. (1974) found that a hot water extract of L. piperatus inhibited Lewis pulmonary adenoma in white mice at inhibition rate against sarcoma 180 in white mice of 80%, and against E. carcinoma at 70%. The extract of L. deliciosus was particularly effective against the acid-fast M. smegmatis and M. tuberculosis (Ying et al. 1987). Barros et al. (2006) reported that the extract of L. deliciosus exhibited antibacterial activities with one Gram-negative (P. aeruginosa) and two Gram-positive bacteria (B. subtilis, B. cereus) as well as antifungal activity (C. albicans, C. neoformans). It is worth noting that the examined extract showed no marked effect on E. coli. Kosanic, Rankovic, and Dasic (2013); (2016)) noted that L. piperatus was found to display high antibacterial and antifungal effects by using microdilution plate method, while methanol extract of L. piperatus showed antimicrobial activity against E. coli, P. vulgaris, and M. smegmatis (Dulger, Yilmaz, and Gucin 2002).
Microbiology in Water-Miscible Metalworking Fluids
Published in Tribology Transactions, 2020
Frederick J. Passman, Peter Küenzi
Microscopy can be used to directly visualize microorganisms in a sample. However, enumeration is difficult (due to the size of bacteria), and differentiation between live and dead cells requires additional staining and more sophisticated instruments. Direct counting after staining with microbe-specific fluorochromes is a suitable method for the enumeration of live microorganisms in environmental samples (189) and theoretically could also be applied to MWFs. Traditional staining procedures such as the acid-fast stain to detect mycobacteria (190) and the Gram stain have been used. However, interferences due to bacteria-sized emulsion droplets and swarf particles can make direct counting in MWFs impractical. Speciation remains challenging beyond differentiation between gram-negative and gram-positive bacteria and other morphological features.
DFT studies of temperature effect on coordination chemistry of Cu(II)-trimethoprim complexes
Published in Journal of Coordination Chemistry, 2018
Malik Zaheer Ahmed, Uzma Habib
Complexes and Schiff bases of trimethoprim have also been investigated for their coordination chemistry and applications. Many metal complexes when present in body fluids or tissue cells show higher activity on many micro-organisms, even on those which have high resistance to antibiotic itself, e.g. 1,10-phenanthroline exhibits higher bacteriostatic effect compared to the ligand on rumen bacteria [7], acid fast bacteria [8] and many gram-positive bacteria [9]. The metal complexes of sulfa-drugs have been found to be more bacteriostatic than the drug itself [10, 11]. For metal ions, although trimethoprim has seven potential binding sites, it interacts as a monodentate ligand, e.g. trimethoprim complexes with metal(II/III), like Cu(II), Zn(II), Pt(II), Ru(II), Fe(III), Cd(III), Co(III), and Co(II).