Activity and characterization of secondary metabolites produced by a new microorganism for control of plant diseases

Microorganisms capable of utilizing vegetable tissues for growth in soils were isolated and their vegetable broth cultures were individually sprayed directly on leaves to test their ability to control Phytophthora blight of bell pepper caused by Phytophthora capsici. Liquid culture of Streptomyces strain TKA-5, a previously undescribed species obtained in this study, displayed several desirable disease control characteristics in nature, including high potency, long lasting and ability to control also black leaf spot of spoon cabbage caused by Alternaria brassicicolca. The extract was fungicidal to P. capsici but fungistatic to A. brassicicola. It was stable at high temperature and high pH. However, after exposure to pH 2 for 24 h, the extract was no longer inhibitory to P. capsici although it was still strongly inhibitory to A. brassicicola. After treatment with cation or anion exchange resins, the extract lost its inhibitory effect against P. capsici but not A. brassicicola. The results suggest that the extract contained two different kinds of inhibitory metabolites, one against P. capsici with both positive and negative charges on its molecule and another against A. brassicicola with no charges on its molecule. The inhibitory metabolites were soluble in ethanol or methanol but not in water, ether or chloroform. They were dialyzable in the membrane tubing with molecular weight cut-off of 10,000, 1000 or 500 but not 100, indicating that the inhibitors have a molecular weight between 500 and 100. Results also showed that both inhibitors are not proteins

Humicola phialophoroides sp nov from soil with potential for biological control of plant diseases

A fungus isolated from soil amended with organic matter and with evidence for biological control of plant diseases, produced both Phialophora- and Humicola-like synanamorphs. Based on ITS1-5.8S-ITS2 sequence analyses, this previously undescribed fungus had a closer relationship with the genus Humicola than with Phialophora and was thus named Humicola phialophoroides

Severe decline of wax apple trees caused by Fusarium solani in northern Taiwan

Wax apple (Syzygium samarangense) is all important fruit crop in Taiwan. Severe decline of wax apple trees was noticed in 2003 in northern suburban Taiwan. A fungus consistently isolated from diseased twigs of declining wax apple trees, was identified as Fusarium soloni based oil morphological characteristics. Fusarium solani from wax apple shared 92.0 to 98.6% and 93.0 to 99.6% intraspecific sequence similarity of ITS and 28S, respectively, with those available in GenBank. Upon inoculation, the isolated F. solani caused twig blight oil healthy wax apple trees, and F solani was reisolated from the diseased twigs, thus fulfilling Koch's postulates. All the control trees remained healthy throughout the experiment. Numerous microconidia of F. solani produced oil the Cut surfaces of diseased twigs under moist conditions were considered to be the main inoculum Source for secondary infection of diseased trees and primary infection of healthy trees

Production of a Fungistatic Substance by Pseudallescheria boydii Isolated from Soil Amended with Vegetable Tissues and Its Significance

Four fungal isolates that were able to use vegetable tissues for multiplication in soil were isolated and identified as Pseudallescheria boydii based on morphological characteristics and ITS sequence similarity. When grown in broth prepared from the same vegetable tissues used in soil amendment, all these isolates of P. boydii produced a substance capable of reducing the disease incidence of black leaf spot of spoon cabbage caused by Alternaria brassicicola and inhibiting the germination of A. brassicicola conidia. The substance, which was fungistatic, was very stable under high temperature and high or low pH value. It was soluble in polar solvents and insoluble in non-polar solvents. Molecular weight estimation and ion exchange ability tests suggest that the fungistatic compound has a molecular weight between 500 and 1,000 and has no charge on its molecule. Results from this study suggest the possession of a strong competitive saprophytic ability by P. boydii, which in turn may explain the widespread occurrence of this human pathogen in soil. Production of a fungistatic substance when P. boydii was grown in broth prepared from vegetable tissues suggests the importance of antibiotic production in its competitive saprophytic colonization of organic matters in soil

Early Improvements in insulin sensitivity and inflammatory markers are induced by pravastatin in nondiabetic subjects with hypercholesterolemia

Background: Statins may improve lipid profiles and inflammation-associated biomarkers, but the effect on insulin sensitivity is controversial. We investigated the effects of 2 doses of pravastatin (40 and 10 mg/day) on insulin sensitivity and serum inflammatory markers in nondiabetic hypercholesterolemic patients. Methods: This was a randomized, parallel, comparative design study. A total of 40 nondiabetic subjects with elevated low-density lipoprotein (LDL) cholesterol were randomized to either the 40 mg pravastatin/day group (n =21) or the 10 mg pravastatin/day group (n=19) for 8 weeks. The fasting serum lipid profile, homeostasis model assessment (HOMA), glucose and insulin response of the two-hour glucose tolerance test (2 h-OGTT), and several inflammatory markers were determined. Results: Eight weeks of pravastatin treatment in both dose groups led to a significant reduction in serum LDL cholesterol, total cholesterol, triglycerides, and total cholesterol/high-density lipoprotein (HDL) cholesterol ratios (all p<0.01 in 40 mg group and all p<0.05 in 10 mg group), though the 40 mg group had greater effects. Although the fasting HOMA insulin resistance did not change significantly in either group, glucose and insulin areas under the curve of 2 h-OGTT were significantly decreased, suggesting improvement in insulin sensitivity post glucose challenge. Serum CD-40 ligand concentration was significantly reduced in the 40 mg pravastatin/day group and soluble P-selectin significantly reduced in both groups. Conclusions: Pravastatin treatment, at 10 mg or 40 mg daily for 8 weeks, reduced serum lipids and some inflammatory markers in nondiabetic hypercholesterolemic subjects. Furthermore, insulin resistance was improved even in short-teen treatment by pravastatin. (C) 2008 Elsevier B.V. All rights reserved

Synthesis, characterization and catalytic activity of lithium and sodium iminophenoxide complexes towards ring-opening polymerization of L-lactide

A series of lithium and sodium iminophenoxide complexes have been successfully synthesized and characterized by X-ray crystallography and investigated as catalysts for the ring opening polymerization of L-lactide. The nature and steric bulk of the ligands coordinated to the central metal ions greatly influence the catalytic properties. Complexes with bidenate ligands exhibit higher catalytic activity than tridentate counterparts because the third coordination atom contends with L-lactide, which decreases activity. Oxygen is the third atom in the tridentate ligand, providing stronger chelation ability with Li and Na than nitrogen or sulfur and occupies the space with which L-lactide is coordinated

The Patient Activation through Community Empowerment/Engagement for Diabetes Management (PACE-D) protocol: A non-randomised controlled trial of personalised care and support planning for persons living with diabetes

10.1186/s12875-020-01173-2BMC Family Practice21111