Production, isolation, and antimicrobial activity of hyalodendrin, a new antibiotic produced by a species of Hyalodendron

1974 ◽  
Vol 20 (5) ◽  
pp. 759-764 ◽  
Author(s):  
M. A. Stillwell ◽  
L. P. Magasi ◽  
G. M. Strunz

A growth inhibitor, designated hyalodendrin (C14H16N2O3S2), was isolated from liquid cultures of a species of Hyalodendron, a Hyphomycete. The isolation and production of hyalodendrin and its physical and chemical properties are described. The in vitro antimicrobial activity of this compound against a broad spectrum of fungi associated with decay and deterioration of trees and forest products was examined. Its inhibitory action against these organisms, as well as against others causing diseases in plants and trees, was found to be superior to that of the antifungal agents cryptosporiopsin, nystatin, or scytalidin. Minimum inhibitory concentrations of hyalodendrin were also established for a number of bacteria and fungi pathogenic to humans. Hyalodendrin compared favorably with benomyl in its ability to inhibit in vitro growth of Ceratocystis ulmi, the causal agent of Dutch elm disease. In seed-germination tests, hyalodendrin had a relatively low degree of phytotoxicity. Acute toxicity to mice (LD50) was established at 75 mg/kg.

1969 ◽  
Vol 15 (6) ◽  
pp. 501-507 ◽  
Author(s):  
M. A. Stillwell ◽  
F. A. Wood ◽  
G. M. Strunz

A growth inhibitor with the molecular formula C10H10O4Cl2 was isolated from a medium which had supported growth of a species of Cryptosporiopsis, an imperfect fungus. The compound was named cryptosporiopsin and was characterized on the basis of its physical and chemical properties. Cryptosporiopsin was active in vitro against many wood-rotting basidiomycetes as well as some phycomycetes, ascomycetes, and deuteromycetes. It was more effective than Dithane M-22 or nystatin against the in vitro spore germination of Phytophthora infestans. It was active to varying degrees against six species of bacteria. Cryptosporiopsin was compared with Orbenin and streptomycin against a penicillin-resistant strain of Staphylococcus aureus.


Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2998
Author(s):  
Mohammed Nadeem Bijle ◽  
Manikandan Ekambaram ◽  
Edward Lo ◽  
Cynthia Yiu

The in vitro study objectives were to investigate the effect of arginine (Arg) incorporation in a 5% sodium fluoride (NaF) varnish on its physical and chemical properties including F/Arg release. Six experimental formulations were prepared with L-arginine (L-Arg) and L-arginine monohydrochloride at 2%, 4%, and 8% w/v in a 5% NaF varnish, which served as a control. The varnishes were subjected to assessments for adhesion, viscosity, and NaF extraction. Molecular dynamics were simulated to identify post-dynamics total energy for NaF=Arg/Arg>NaF/Arg<NaF concentrations. The Arg/F varnish release profiles were determined in polyacrylic lactate buffer (pH-4.5; 7 days) and artificial saliva (pH-7; 1 h, 24 h, and 12 weeks). Incorporation of L-Arg in NaF varnish significantly influences physical properties ameliorating retention (p < 0.001). L-Arg in NaF varnish institutes the Arg-F complex. Molecular dynamics suggests that NaF>Arg concentration denotes the stabilized environment compared to NaF<Arg (p < 0.001). The 2% Arg-NaF exhibits periodic perennial Arg/F release and shows significantly higher integrated mean F release than NaF (p < 0.001). Incorporating 2% L-arginine in 5% NaF varnish improves its physical properties and renders a stable matrix with enduring higher F/Arg release than control.


Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5722
Author(s):  
Yijie Lou ◽  
Kaxi Yu ◽  
Xiajun Wu ◽  
Zhaojun Wang ◽  
Yusheng Cui ◽  
...  

Resveratrol (RSV) and polydatin (PD) have been widely used to treat several chronic diseases, such as atherosclerosis, pulmonary fibrosis, and diabetes, among several others. However, their low solubility hinders their further applications. In this work, we show that the solubility of PD can be boosted via its co-crystallization with L-proline (L-Pro). Two different phases of co-crystals, namely the RSV-L-Pro (RSV:L-Pro = 1:2) and PD-L-Pro (PD:L-Pro = 1: 3), have been prepared and characterized. As compared to the pristine RSV and PD, the solubility and dissolution rates of PD-L-Pro in water (pH 7.0) exhibited a 15.8% increase, whereas those of RSV-L-Pro exhibited a 13.8% decrease. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay of pristine RSV, PD, RSV-L-Pro, and PD-L-Pro against lung cancer cell line A549 and human embryonic kidney cell line HEK-293 indicated that both compounds showed obvious cytotoxicity against A549, but significantly reduced cytotoxicity against HEK-293, with PD/PD-L-Pro further exhibiting better biological safety than that of RSV/RSV-L-Pro. This work demonstrated that the readily available and biocompatible L-Pro can be a promising adjuvant to optimize the physical and chemical properties of RSV and PD to improve their pharmacokinetics.


2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Edward B Neufeld ◽  
Alice Ossoli ◽  
Seth G Thacker ◽  
Boris Vaisman ◽  
Milton Pryor ◽  
...  

Familial lecithin:cholesterol acyltransferase (LCAT) deficiency (FLD) is characterized by low HDL, accumulation of an abnormal cholesterol-rich multilamellar particle called lipoprotein-X (LpX) in plasma, and renal disease. The aim of our study was to determine if LpX is nephrotoxic and to gain insight into the pathogenesis of FLD renal disease. We administered a synthetic LpX, nearly identical to endogenous LpX in its physical, and chemical properties, to wild-type and Lcat -/- mice. Our in vitro and in vivo studies demonstrated an apoA-I and LCAT-dependent pathway for LpX conversion to HDL-like particles, which likely mediates normal plasma clearance of LpX. Plasma clearance of exogenous LpX was markedly delayed in Lcat -/- mice, which have low HDL but only minimal amounts of endogenous LpX and do not spontaneously develop renal disease. Chronically administered exogenous LpX deposited in all renal glomerular cellular and matrical compartments of Lcat -/- mice, and induced proteinuria and nephrotoxic gene changes, as well as all of the hallmarks of FLD renal disease as assessed by histological, TEM, and SEM analyses. Extensive in vivo EM studies revealed LpX uptake by macropinocytosis into mouse glomerular endothelial cells, podocytes, and mesangial cells and delivery to lysosomes, where it was degraded. Endocytosed LpX appeared to be degraded by both human podocyte and mesangial cell lysosomal PLA 2 and induced podocyte secretion of pro-inflammatory IL-6 in vitro and renal Cxl10 expression in Lcat -/- mice. In conclusion, LpX is a nephrotoxic particle that in the absence of LCAT induces all of the histological and functional hallmarks of FLD and hence may serve as a biomarker for monitoring recombinant LCAT therapy. In addition, our studies suggest that LpX-induced loss of endothelial barrier function and release of cytokines by renal glomerular cells likely plays a role in the initiation and progression of FLD nephrosis.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Sonja Ž. Đurić ◽  
Sandra Vojnovic ◽  
Tina P. Andrejević ◽  
Nevena Lj Stevanović ◽  
Nada D. Savić ◽  
...  

1,2-Bis(4-pyridyl)ethane (bpa) and 1,2-bis(4-pyridyl)ethene (bpe) were used for the synthesis of polynuclear silver(I) complexes, {[Ag(bpa)]NO3}n (1), {[Ag(bpa)2]CF3SO3.H2O}n (2) and {[Ag(bpe)]CF3SO3}n (3). In complexes 1–3, the corresponding nitrogen-containing heterocycle acts as a bridging ligand between two Ag(I) ions. In vitro antimicrobial activity of these complexes, along with the ligands used for their synthesis, was evaluated against the broad panel of Gram-positive and Gram-negative bacteria and fungi. The silver(I) complexes 1–3 showed selectivity towards Candida spp. and Gram-negative Escherichia coli in comparison to the other investigated bacterial strains, effectively inhibiting the growth of four different Candida species with minimal inhibitory concentrations (MICs) between 2.5 and 25 μg/mL and the growth of E. coli, with MIC value being 12.5 μg/mL. Importantly, complex 2 significantly reduced C. albicans filamentation, an essential process for its pathogenesis. Antiproliferative effect on the normal human lung fibroblast cell line MRC-5 was also evaluated with the aim of determining the therapeutic potential of the complexes 1–3. The interactions of these complexes with calf thymus DNA (ctDNA) and bovine serum albumin (BSA) were studied to evaluate their binding activities towards these biomolecules for possible insights on their mode of action.


MRS Advances ◽  
2019 ◽  
Vol 5 (12-13) ◽  
pp. 633-642
Author(s):  
Jun Hon Pang ◽  
Christian Wischke ◽  
Andreas Lendlein

ABSTRACT:Multifunctional biopolymer-based materials are promising candidates for next generation regenerative biomaterials. Understanding the degradation behavior of biomaterials is vital for ensuring biological safety, as well as for better control of degradation properties based on rational design of a material’s physical and chemical characteristics. In this study, we decipher the degradation of a hydrogel prepared from gelatin and lysine diisocyanate ethyl ester (LDI) using in vitro models, which simulate hydrolytic, oxidative and enzymatic degradation (collagenase). Gravimetrical, morphological, mechanical and chemical properties were evaluated. Notably, the hydrogels were relatively resistant to hydrolytic degradation, but degraded rapidly within 21 days (>95% mass loss) under oxidative and collagenase degradation. Oxidative and collagenase degradation rapidly decreased the storage and loss modulus of the hydrogels, and slightly increased their viscous component (tan δ). For each degradation condition, the results suggest different possible degradation pathways associated to the gelatin polypeptide backbone, urea linkages and ester groups. The primary degradation mechanisms for the investigated gelatin based hydrogels are oxidative and enzymatic in nature. The relative hydrolytic stability of the hydrogels should ensure minimal degradation during storage and handling prior to application in surgical theatres.


2008 ◽  
Vol 25 (No. 2) ◽  
pp. 81-89 ◽  
Author(s):  
A. Adiguzel ◽  
H. Ozer ◽  
H. Kilic ◽  
B. Cetin

The present work reports the <i>in vitro</i> antimicrobial activities of the essential oil and methanol extract from <i>Satureja hortensis</i> as well as the content of its essential oil. The chemical composition of hydrodistilled essential oil of Satureja hortensis was analysed by means of GC-MS. Thirty constituents were identified. The main constituents of the oil were thymol (40.54%), &gamma;-terpinene (18.56%), carvacrol (13.98%), and <i>p</i>-cymene (8.97). The essential oil of <i>Satureja hortensis</i> exhibited the activity against 25 bacteria, 8 fungi, and a yeast, <i>C. albicans</i>; exerting the Minimum Inhibitory Concentration values (MIC) ranging from 15.62 to 250 &micro;l/ml. Similarly, methanol extract of the plant also showed antimicrobial activity.


2019 ◽  
Vol 391 ◽  
pp. 215-220 ◽  
Author(s):  
Andrey N. Dmitriev ◽  
R.V. Petukhov ◽  
G.Yu. Vitkina ◽  
E.A. Vyaznikova

Questions regarding the oxidizing roasting of raw iron ore materials (agglomerate and pellets) are studied. Features of the phase structure of raw iron ore materials containing titanium and vanadium are discussed. Reducibility, durability, and temperatures of the softening and melting of metallurgical raw iron ore materials are studied in vitro. Object of research – titaniferous ores with various titanium dioxide content. The behavior of agglomerate and pellets in a blast furnace are studied, as well as the influence of their physical and chemical properties on heat and mass transfer processes using a mathematical model of the blast furnace process [1].


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