scholarly journals Isolation and Bioactivity of Secondary Metabolites from Solid Culture of the Fungus, Alternaria sonchi

Biomolecules ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 81
Author(s):  
Anna Dalinova ◽  
Leonid Chisty ◽  
Dmitry Kochura ◽  
Varvara Garnyuk ◽  
Maria Petrova ◽  
...  
Keyword(s):  
Antimicrobial Properties ◽  
Solid Substrate ◽  
Solid Culture ◽  
Couch Grass ◽  
Elytrigia Repens ◽  
Waste Solid ◽  
Low Cytotoxicity ◽  
Sonchus Arvensis ◽  
Related Compounds ◽  
Leaf Disks

The fungus, Alternaria sonchi is considered to be a potential agent for the biocontrol of perennial sowthistle (Sonchus arvensis). A new chlorinated xanthone, methyl 8-hydroxy-3-methyl-4-chloro-9-oxo-9H-xanthene-1-carboxylate (1) and a new benzophenone derivative, 5-chloromoniliphenone (2), were isolated together with eleven structurally related compounds (3–13) from the solid culture of the fungus, which is used for the production of bioherbicidal inoculum of A. sonchi. Their structures were determined by spectroscopic (mostly by NMR and MS) methods. Alternethanoxins A and B, which were reported in A. sonchi earlier, were re-identified as moniliphenone and pinselin, respectively. The isolated compounds were tested for phytotoxic, antimicrobial, insecticidal, cytotoxic and esterase-inhibition activities. They did not demonstrate high phytotoxicity (lesions up to 2.5 mm in diameter/length at a concentration of 2 mg/mL) when tested on leaf disks/segments of perennial sowthistle (Sonchus arvensis) and couch grass (Elytrigia repens). They did not possess acute toxicity to Paramecium caudatum, and showed moderate to low cytotoxicity (IC50 > 25 µg/mL) for U937 and K562 tumor cell lines. However, chloromonilicin and methyl 3,8-dihydroxy-6-methyl-4-chloro-9-oxo-9H-xanthene-1-carboxylate (4) were shown to have antimicrobial properties with MIC 0.5–5 µg/disc. Compound 4 and chloromonilinic acid B were found to have contact insecticidal activity to wheat aphid (Schizaphis graminum) at 1 mg/mL. Compounds 2 and methyl 3,8-dihydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate displayed selective carboxylesterase inhibition activity at concentration of 100 µg/mL. Therefore, the waste solid substrate for production of A. sonchi spores can be re-utilized for the isolation of a number of valuable natural products.

scholarly journals Antimicrobial Activity of Curcumin in Nanoformulations: A Comprehensive Review

2021 ◽  
Vol 22 (13) ◽  
pp. 7130
Author(s):  
Jeffersson Krishan Trigo-Gutierrez ◽  
Yuliana Vega-Chacón ◽  
Amanda Brandão Soares ◽  
Ewerton Garcia de Oliveira Mima
Keyword(s):  
Polymeric Nanoparticles ◽  
Graphene Quantum Dots ◽  
Antimicrobial Properties ◽  
Antimicrobial Effect ◽  
Clinical Scenarios ◽  
Low Cytotoxicity ◽  
Bacteria And Fungi ◽  
Drug Resistant Strains

Curcumin (CUR) is a natural substance extracted from turmeric that has antimicrobial properties. Due to its ability to absorb light in the blue spectrum, CUR is also used as a photosensitizer (PS) in antimicrobial Photodynamic Therapy (aPDT). However, CUR is hydrophobic, unstable in solutions, and has low bioavailability, which hinders its clinical use. To circumvent these drawbacks, drug delivery systems (DDSs) have been used. In this review, we summarize the DDSs used to carry CUR and their antimicrobial effect against viruses, bacteria, and fungi, including drug-resistant strains and emergent pathogens such as SARS-CoV-2. The reviewed DDSs include colloidal (micelles, liposomes, nanoemulsions, cyclodextrins, chitosan, and other polymeric nanoparticles), metallic, and mesoporous particles, as well as graphene, quantum dots, and hybrid nanosystems such as films and hydrogels. Free (non-encapsulated) CUR and CUR loaded in DDSs have a broad-spectrum antimicrobial action when used alone or as a PS in aPDT. They also show low cytotoxicity, in vivo biocompatibility, and improved wound healing. Although there are several in vitro and some in vivo investigations describing the nanotechnological aspects and the potential antimicrobial application of CUR-loaded DDSs, clinical trials are not reported and further studies should translate this evidence to the clinical scenarios of infections.

scholarly journals A Concept of a Compact and Inexpensive Device for Controlling Weeds with Laser Beams

Agronomy ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1616
Author(s):  
Ildar Rakhmatulin ◽  
Christian Andreasen
Keyword(s):  
Neural Network ◽  
Decision Model ◽  
Control Device ◽  
Guidance System ◽  
Laser Beams ◽  
Laser Guidance ◽  
Couch Grass ◽  
Elytrigia Repens ◽  
Weed Plants ◽  
Plant Length

A prototype of a relatively cheap laser-based weeding device was developed and tested on couch grass (Elytrigia repens (L.) Desv. ex Nevski) mixed with tomatoes. Three types of laser were used (0.3 W, 1 W, and 5 W). A neural network was trained to identify the weed plants, and a laser guidance system estimated the coordinates of the weed. An algorithm was developed to estimate the energy necessary to harm the weed plants. We also developed a decision model for the weed control device. The energy required to damage a plant depended on the diameter of the plant which was related to plant length. The 1 W laser was not sufficient to eliminate all weed plants and required too long exposure time. The 5 W laser was more efficient but also harmed the crop if the laser beam became split into two during the weeding process. There were several challenges with the device, which needs to be improved upon. In particular, the time of exposure needs to be reduced significantly. Still, the research showed that it is possible to develop a concept for laser weeding using relatively cheap equipment, which can work in complicated situations where weeds and crop are mixed.

scholarly journals Syntheses and Antimicrobial Properties of the Related Compounds of Decanoylacetaldehyde. III

1954 ◽  
Vol 74 (8) ◽  
pp. 819-820 ◽  
Author(s):  
Takuo Kosuge ◽  
Hideo Okeda ◽  
Yutaka Teraishi ◽  
Haruyuki Ito ◽  
Shogo Kosaka
Keyword(s):  
Antimicrobial Properties ◽  
Related Compounds

scholarly journals Brevinin-1GHd: a novel Hylarana guentheri skin secretion-derived Brevinin-1 type peptide with antimicrobial and anticancer therapeutic potential

2020 ◽  
Vol 40 (5) ◽  
Author(s):  
Yangyang Jiang ◽  
Yue Wu ◽  
Tao Wang ◽  
Xiaoling Chen ◽  
Mei Zhou ◽  
...  
Keyword(s):  
Therapeutic Potential ◽  
Human Cancer ◽  
Wide Spectrum ◽  
Antimicrobial Properties ◽  
Skin Secretion ◽  
Anticancer Activities ◽  
Peptide Analog ◽  
Wide Range ◽  
Low Cytotoxicity ◽  
Short Time

Abstract Host-defense antimicrobial peptides (AMPs) from amphibians are usually considered as one of the most promising next-generation antibiotics because of their excellent antimicrobial properties and low cytotoxicity. In the present study, one novel Brevinin-1 type peptide, Brevinin-1GHd, was isolated and characterized from the skin secretion of the frog, Hylarana guentheri. Brevinin-1GHd was found to possess a wide range of antimicrobial activity through penetrating the bacterial membrane within a short time while showing low hemolysis at bactericidal concentrations, even against the resistant strains. It also inhibited and eradicated biofilms that are thought to be closely related to the rise in resistance. Meanwhile, Brevinin-1GHd exhibited wide-spectrum anti-proliferation activity toward human cancer lines. Taken together, these results indicate that Brevinin-1GHd with its excellent antimicrobial and anticancer activities is a promising candidate for a novel antibiotic agent, and study of its structure–activity relationships also provided a rational template for further research and peptide analog design.

Effect of integrated management of couch grass (Elytrigia repens) on soil quality and crop nutrition

1998 ◽  
Vol 130 (3) ◽  
pp. 323-328 ◽  
Author(s):  
Y. K. SOON ◽  
A. L. DARWENT
Keyword(s):  
Microbial Biomass ◽  
Soil Quality ◽  
Green Manure ◽  
Integrated Management ◽  
Red Clover ◽  
Crop Rotations ◽  
Continuous Cropping ◽  
Soil N ◽  
Couch Grass ◽  
Elytrigia Repens

The effects of suppressing couch grass (Elytrigia repens L.), through integrated management, on soil biological quality and N and P nutrition of barley (Hordeum vulgare L.) were evaluated in a field experiment (1987–92) on a Dark Grey soil in Alberta, Canada. The management practices consisted of combinations of herbicide application, crop rotations and tillage treatments. The 3-year crop sequences consisted of continuous barley, canola (Brassica rapa L.)–barley–barley, fallow–barley–barley, and barley or canola undersown with red clover (Trifolium pratense L.)–red clover green manure–barley. In 1992, the sixth year of the experiment, soil and plant samples were analysed for nutrient content. Treatments that consisted of spring and autumn tillage only did not suppress couch grass and produced low barley yields and N and P uptake. More N was immobilized in couch grass shoots and rhizomes and soil microbial biomass with these treatments than with similar herbicide-treated crop rotations. Tillage-plus-herbicide treatments effectively suppressed couch grass and enabled the barley crop to compete for soil N, however, both spring and autumn tillage were required for weed control. The fallow treatment impaired soil quality by reducing soil and microbial C and N, but produced similar barley yields as continuous cropping with tillage-plus-chemical control. Red clover ploughed in for green manure enhanced soil quality indicators such as soil and microbial biomass C, total and mineralizable soil N, and microbial N, but did not increase barley yield compared to continuous grain cropping.

scholarly journals Pulsed Laser Deposited Biocompatible Lithium-Doped Hydroxyapatite Coatings with Antimicrobial Activity

Coatings ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 54 ◽  
Author(s):  
Liviu Duta ◽  
Mariana Chifiriuc ◽  
Gianina Popescu-Pelin ◽  
Coralia Bleotu ◽  
Gratiela Gradisteanu ◽  
...  
Keyword(s):  
Antimicrobial Properties ◽  
Pulsed Laser ◽  
Dermal Fibroblasts ◽  
Biological Origin ◽  
Sustainable Resources ◽  
Skin Cells ◽  
Hydroxyapatite Coatings ◽  
Low Cytotoxicity ◽  
Implant Coatings ◽  
New Generation

Simple and lithium-doped biological-origin hydroxyapatite layers were synthesized by Pulsed Laser Deposition technique on medical grade Ti substrates. Cytotoxic effects of lithium addition and the biocompatibility of obtained coatings were assessed using three cell lines of human origin (new initiated dermal fibroblasts, immortalized keratinocytes HaCaT, and MG-63 osteosarcoma). Antimicrobial properties of obtained coatings were assessed on two strains (i.e., Staphylococcus aureus and Candida albicans), belonging to species representative for the etiology of medical devices biofilm-associated infections. Our findings suggest that synthesized lithium-doped coatings exhibited low cytotoxicity on human osteosarcoma and skin cells and therefore, an excellent biocompatibility, correlated with a long-lasting anti-staphylococcal and -fungal biofilm activity. Along with low fabrication costs generated by sustainable resources, these biological-derived materials demonstrate their promising potential for future prospective solutions—viable alternatives to commercially available biomimetic HA implants—for the fabrication of a new generation of implant coatings.

Sign in / Sign up

Export Citation Format

Share Document