Presence of a fungal inhibitor in the pericarps of Acer saccharum fruits

1970 ◽  
Vol 48 (12) ◽  
pp. 2109-2116 ◽  
Author(s):  
D. P. Webb ◽  
V. P. Agnihotri
Keyword(s):  
Acer Saccharum ◽  
Fungal Pathogens ◽  
Soil Fungi ◽  
Pinus Resinosa ◽  
Water Soluble ◽  
Damping Off ◽  
Pythium Irregulare ◽  
Low Concentrations ◽  
Heat Treated ◽  
Germ Tubes

The present data suggest that the pericarps of Acer saccharum contain a water-soluble fungal inhibitor that protects the fruit from fungal pathogens. Aqueous pericarp extracts effectively inhibited mycelial growth of several pathogenic soil fungi, particularly species of Pythium and Rhizoctonia. The extract also controlled damping-off of Pinus resinosa seedlings and inhibited microbial respiration in nursery soil. Even at relatively low concentrations (0.003% w/v), the extract lysed germ tubes and induced morphological abnormalities. Bioassays of chromatographically partitioned extracts indicated that four major compounds were present, one capable of markedly inhibiting germination of sporangia of Pythium irregulare. Two-dimensional paper chromatography of heat-treated extracts indicated that three additional spots were present. One spot showed characteristics of gallic acid; this suggests that the inhibitor is a gallotannin.

scholarly journals Influence of dinitroorthocresol (DNOC) on physiology and morphology of soil fungi. III. The effect of various concentrations of DNOC on spore germination activity and morphology of germ tubes

2014 ◽  
Vol 20 (1) ◽  
pp. 45-61 ◽  
Author(s):  
Teresa Korniłłowicz
Keyword(s):  
Spore Germination ◽  
Soil Fungi ◽  
Morphological Changes ◽  
Fungal Spores ◽  
Fungal Spore ◽  
Low Concentrations ◽  
Mucor Mucedo ◽  
High Concentrations ◽  
Germ Tubes

In the present paper low concentrations (l -10 mcg/ml) of DNOC, in general, were not found to restrain germination of fungal spores. High concentrations (25-200 mcg/ml) were sporostatic and sporocidal Disturbances of fungal spore germination in the presence of DNOC were often accompanied by morphological changes of spores and germ tubes, <i>Mucor mucedo</i> under the influence of DNOC developed budding cels besides hyphae.

scholarly journals Transformation of Construction Cement to a Self-Healing Hybrid Binder

2019 ◽  
Vol 20 (12) ◽  
pp. 2948 ◽  
Author(s):  
Werner E.G. Müller ◽  
Emad Tolba ◽  
Shunfeng Wang ◽  
Qiang Li ◽  
Meik Neufurth ◽  
...  
Keyword(s):  
Soil Bacteria ◽  
Construction Material ◽  
Water Soluble ◽  
The Self ◽  
Average Chain Length ◽  
Self Healing ◽  
Cement Concrete ◽  
Low Concentrations ◽  
Natural Mechanism ◽  
Long Chain

A new biomimetic strategy to im prove the self-healing properties of Portland cement is presented that is based on the application of the biogenic inorganic polymer polyphosphate (polyP), which is used as a cement admixture. The data show that synthetic linear polyp, with an average chain length of 40, as well as natural long-chain polyP isolated from soil bacteria, has the ability to support self-healing of this construction material. Furthermore, polyP, used as a water-soluble Na-salt, is subject to Na+/Ca2+ exchange by the Ca2+ from the cement, resulting in the formation of a water-rich coacervate when added to the cement surface, especially to the surface of bacteria-containing cement/concrete samples. The addition of polyP in low concentrations (<1% on weight basis for the solids) not only accelerated the hardening of cement/concrete but also the healing of microcracks present in the material. The results suggest that long-chain polyP is a promising additive that increases the self-healing capacity of cement by mimicking a bacteria-mediated natural mechanism.

scholarly journals Colorless and Transparent Polyimide Microporous Film with Excellent Physicochemical Property

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1298
Author(s):  
Jong Won Kim ◽  
Seon Ju Lee ◽  
Moon Young Choi ◽  
Jin-Hae Chang
Keyword(s):  
Pore Size ◽  
Porous Membrane ◽  
Amic Acid ◽  
Water Soluble ◽  
Poly Vinyl Alcohol ◽  
Thermal Stabilities ◽  
Blend Films ◽  
Hydrogen Bonding Interactions ◽  
Heat Treated ◽  
Microporous Film

4,4′-(4,4′-isopropylidenediphenoxy)bis(phthalic anhydride) (BPADA) as a dianhydride and bis(3-aminophenyl) sulfone (APS) and bis(3-amino-4-hydroxyphenyl) sulfone (APS-OH) as diamines were used to synthesize two types of poly(amic acid) (PAA). Varying amounts (0–5.0 wt%) of water-soluble poly(vinyl alcohol) (PVA) were mixed with PAA, and the resulting blend was heat-treated at different stages to obtain the colorless and transparent polyimide (CPI) blend films. The synthesized blended film completely removed water-soluble PVA in water. The possibility as a porous membrane according to the pore size varied according to the amount of PVA was investigated. The dispersibility and compatibility of CPI containing APS-OH monomer were higher than those of the APS monomer. This could be attributed to the hydrogen-bonding interactions between the CPI main chains and PVA. Scanning electron microscopy was conducted to characterize the material. The results revealed that the pore size of the CPI blend film increased as the PVA concentration increased. It was confirmed that uniform pores of μm-size were observed in CPI. The thermal stabilities, morphologies, optical properties, and solubilities of two CPIs obtained using APS and APS-OH monomers were investigated and their properties were compared with each other.

The effect of a benzodiazepine, flurazepam, on the response of in vitro skeletal muscle preparations to muscle relaxants: are purines or their receptors involved?

1982 ◽  
Vol 60 (7) ◽  
pp. 877-884 ◽  
Author(s):  
John T. Hamilton ◽  
Peggy A. Stone
Keyword(s):  
Skeletal Muscle ◽  
Phrenic Nerve ◽  
Neuromuscular Blocking ◽  
Muscle Relaxants ◽  
Water Soluble ◽  
Neuromuscular Activity ◽  
Changing Trends ◽  
Low Concentrations ◽  
Partial Blockade

Changing trends in the use of anxiolytic agents and recent reassessment of their neuropharmacological activity has prompted this evaluation of the peripheral neuromuscular activity of the benzodiazepine, flurazepam. In previous reports we have documented peripheral neuromuscular activity of chlordiazepoxide and diazepam on the rat phrenic nerve diaphragm preparation. The water soluble benzodiazepine, flurazepam, has been studied on the rat phrenic nerve diaphragm and frog rectus abdominis in vitro. On the former preparation flurazepam enhanced and then blocked the response to indirect electrical stimulation (0.2 Hz) and readily blocked posttetanic potentiation and prevented the preparation from sustaining a tetanic contracture (30 Hz). On the later preparation, flurazepam blocked in a noncompetitive manner the response of the frog muscle to applied cholinergic agonists. Studies on the rat preparation with the neuromuscular blocking drug succinylcholine have shown an unexpected protection against blockade in preparations pretreated with low concentrations of flurazepam. This was not observed when flurazepam was given prior to d-tubocurarinc. The application of adenosine to rat diaphragms during steady-state partial blockade caused by flurazepam or d-tubocurarine showed an inhibiting action of adenosine which was reversed by theophylline. Pretreatment of rat preparations with dipyridamole significantly enhanced the blocking action of standard concentrations of succinylcholine.These results, along with those in the literature, encourage a reassessment of the action of purines and benzodiazepines on skeletal muscle and encourage a consideration of a possible involvement of purinergic neuromodulation of transmission which is unmasked when the safety factor for transmission is altered by muscle relaxants. The possible clinical significance of protection against succinylcholine by benzodiazepines is noted.

scholarly journals First Report of Damping-Off on Cucumis melo Caused by Pythium irregulare in South Korea

Plant Disease ◽  
2020 ◽  
Vol 104 (11) ◽  
pp. 3060-3060
Author(s):  
Mi-Jeong Park ◽  
Chang-Gi Back ◽  
Jong-Han Park
Keyword(s):  
South Korea ◽  
Cucumis Melo ◽  
Damping Off ◽  
Pythium Irregulare ◽  
First Report

scholarly journals Candida albicans Sterol C-14 Reductase, Encoded by the ERG24 Gene, as a Potential Antifungal Target Site

2002 ◽  
Vol 46 (4) ◽  
pp. 947-957 ◽  
Author(s):  
N. Jia ◽  
B. Arthington-Skaggs ◽  
W. Lee ◽  
C. A. Pierson ◽  
N. D. Lees ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Fungal Pathogens ◽  
Antifungal Agents ◽  
Fungal Infections ◽  
Brefeldin A ◽  
Agricultural Applications ◽  
Mouse Model System ◽  
Cellular Inhibitors ◽  
Germ Tubes ◽  
Doubling Times

ABSTRACT The incidence of fungal infections has increased dramatically, which has necessitated additional and prolonged use of the available antifungal agents. Increased resistance to the commonly used antifungal agents, primarily the azoles, has been reported, thus necessitating the discovery and development of compounds that would be effective against the major human fungal pathogens. The sterol biosynthetic pathway has proved to be a fertile area for antifungal development, and steps which might provide good targets for novel antifungal development remain. The sterol C-14 reductase, encoded by the ERG24 gene, could be an effective target for drug development since the morpholine antifungals, inhibitors of Erg24p, have been successful in agricultural applications. The ERG24 gene of Candida albicans has been isolated by complementation of a Saccharomyces cerevisiae erg24 mutant. Both copies of the C. albicans ERG24 gene have been disrupted by using short homologous regions of the ERG24 gene flanking a selectable marker. Unlike S. cerevisiae, the C. albicans ERG24 gene was not required for growth, but erg24 mutants showed several altered phenotypes. They were demonstrated to be slowly growing, with doubling times at least twice that of the wild type. They were also shown to be significantly more sensitive to an allylamine antifungal and to selected cellular inhibitors including cycloheximide, cerulenin, fluphenazine, and brefeldin A. The erg24 mutants were also slightly resistant to the azoles. Most importantly, erg24 mutants were shown to be significantly less pathogenic in a mouse model system and failed to produce germ tubes upon incubation in human serum. On the basis of these characteristics, inhibitors of Erg24p would be effective against C. albicans.

No Effect of Soybean Lipoxygenase on Aflatoxin Production in Aspergillus flavus–Inoculated Seeds

2002 ◽  
Vol 65 (12) ◽  
pp. 1984-1987 ◽  
Author(s):  
J. E. MELLON ◽  
P. J. COTTY
Keyword(s):  
Aspergillus Flavus ◽  
Fungal Pathogens ◽  
Seed Viability ◽  
Soybean Seed ◽  
Fungal Growth ◽  
Aflatoxin Production ◽  
Aflatoxin Contamination ◽  
Soybean Seeds ◽  
Heat Treated ◽  
Significant Difference

Soybean lines lacking lipoxygenase (LOX) activity were compared with soybean lines having LOX activity for the ability to support growth and aflatoxin B1 production by the fungal seed pathogen Aspergillus flavus. Whole seeds, broken seeds, and heat-treated (autoclaved) whole seeds were compared. Broken seeds, irrespective of LOX presence, supported excellent fungal growth and the highest aflatoxin levels. Autoclaved whole seeds, with or without LOX, produced good fungal growth and aflatoxin levels approaching those of broken seeds. Whole soybean seeds supported sparse fungal growth and relatively low aflatoxin levels. There was no significant difference in aflatoxin production between whole soybean seeds either with or without LOX, although there did seem to be differences among the cultivars tested. The heat treatment eliminated LOX activity (in LOX+ lines), yet aflatoxin levels did not change substantially from the broken seed treatment. Broken soybean seeds possessed LOX activity (in LOX+ lines) and yet yielded the highest aflatoxin levels. The presence of active LOX did not seem to play the determinant role in the susceptibility of soybean seeds to fungal pathogens. Seed coat integrity and seed viability seem to be more important characteristics in soybean seed resistance to aflatoxin contamination. Soybean seeds lacking LOX seem safe from the threat of increased seed pathogen susceptibility.

scholarly journals In Vitro Antimicrobial Activity of the Decontaminant HybenX® Compared to Chlorhexidine and Sodium Hypochlorite against Common Bacterial and Yeast Pathogens

Antibiotics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 188 ◽  
Author(s):  
Alberto Antonelli ◽  
Luca Giovannini ◽  
Ilaria Baccani ◽  
Valentina Giuliani ◽  
Riccardo Pace ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Sodium Hypochlorite ◽  
Fungal Pathogens ◽  
Antimicrobial Agents ◽  
Fungal Infections ◽  
Yeast Strains ◽  
Low Concentrations ◽  
Endodontic Infections ◽  
Reference Strains

The recent increase in infections mediated by drug-resistant bacterial and fungal pathogens underlines the urgent need for novel antimicrobial compounds. In this study, the antimicrobial activity (inhibitory and cidal) of HybenX®, a novel dessicating agent, in comparison with commonly used sodium hypochlorite and chlorhexidine, against a collection of bacterial and yeast strains representative of the most common human pathogenic species was evaluated. The minimal inhibitory, bactericidal, and fungicidal concentrations (MIC, MBC, and MFC, respectively) of the three different antimicrobial agents were evaluated by broth microdilution assays, followed by subculturing of suitable dilutions. HybenX® was active against 26 reference strains representative of staphylococci, enterococci, Enterobacterales, Gram-negative nonfermenters, and yeasts, although at higher concentrations than sodium hypochlorite and chlorhexidine. HybenX® MICs were 0.39% for bacteria (with MBCs ranging between 0.39% and 0.78%), and 0.1–0.78% for yeasts (with MFCs ranging between 0.78% and 1.6%). HybenX® exhibited potent inhibitory and cidal activity at low concentrations against several bacterial and yeast pathogens. These findings suggest that HybenX® could be of interest for the treatment of parodontal and endodontic infections and also for bacterial and fungal infections of other mucous membranes and skin as an alternative to sodium hypochlorite and chlorhexidine.

scholarly journals Effect of the brewing process on the acrylamide content in coffee beverages

2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Joanna Michalak ◽  
Marta Czarnowska-Kujawska ◽  
Elżbieta Gujska ◽  
Joanna Klepacka ◽  
Elżbieta Tońska
Keyword(s):  
Water Soluble ◽  
Mean Values ◽  
Short Contact Time ◽  
Heat Treated ◽  
Carcinogenic Substances ◽  
Brewing Process ◽  
Espresso Coffee ◽  
Brewing Method ◽  
Filtered Coffee ◽  
Ground Coffee

AbstractOne of the latest neurotoxic and carcinogenic substances discovered in food is acrylamide (AA). The main pathway for AA formation in foods is the Maillard reaction (MR). Heat treated carbohydrate-rich foods such as potato, cereal and bakery products, together with coffee contain high levels of acrylamide. The high consumption of coffee in many countries makes it a potentially significant source of daily exposure to acrylamide. The purpose of the present investigation was to study the influence of the brewing method on the acrylamide level in coffee beverages. The experiment was performed with six different roasted coffee from local supermarkets. For coffee beverages preparation four different methods were used: boiled coffee (Turkish coffee), steeping (French press coffee), infusion (filtered coffee), and Italian pressure method (espresso coffee). Each time coffee beans were mechanically powdered and 100 ml brew was prepared using 6 g of ground coffee. AA contents in the brew coffee samples were determined by the RP - HPLC - DAD method. The results for AA contents were presented as mean values ± standard deviations (SDs) of six independent samples, analysed in triplicate (n = 18). Obtained results showed that the method of brewing coffee influences the level of AA in infusions. AA concentrations for Turkish coffee (4.10 μg/100 ml), French press (3.19 μg/100 ml) and filtered coffee (2.95 μg/100 ml) were higher than for espresso (2.13 μg/100 ml). Results showed also that the highly water-soluble acrylamide is easily extracted from the ground coffee to the liquid phase of the beverage. The extraction percentage variation according to the brew method was: from 52% for espresso to 95% for Turkish coffee. The brewing procedure for espresso extracted acrylamide incompletely from ground coffee comparing to other brewing methods, due to the short contact time between coffee and water. When compared with other common coffee beverages, espresso is the most concentrated brew. However, its acrylamide content per cup may be lower, due to the lower level of this substance extraction to the brew. The brewing time has a significant influence on the extraction level of AA for the beverage.

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