Graft Copolymerization of Acrylonitrile and Ethyl Acrylate onto Pinus Roxburghii Wood Surface Enhanced Physicochemical Properties and Antibacterial Activity

As a natural and the most abundant material, wood was used as a scaffold for the grafting of acrylonitrile (AN) and ethyl acrylate (EA) to develop a novel grafted wood. Thus, chemical modification of the wood was carried out by means of grafting. It is clear from the characterization techniques (FTIR, SEM, and XRD) that grafting of acrylonitrile (AN) and ethyl acrylate (EA) was successfully performed on the Pinus roxburghii wood. Monomer and initiator concentration, temperature, time, and pH parameters have been varied to obtain the maximum percent grafting yield. A significant influence was observed on the physicochemical properties, morphological structure, and bacterial resistant nature after the graft copolymerization of AN + EA on the raw wood. This approach of grafting of wood would lead to the construction of a new class of materials with better properties and will also promote innovative consumption of renewable wood.

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Large-scale High-throughput Screening Revealed 5'-(carbonylamino)-2,3'- bithiophene-4'-carboxylate as Novel Template for Antibacterial Agents

Current Drug Discovery Technologies ◽

10.2174/1570163816666190603095521 ◽

2020 ◽

Vol 17 (5) ◽

pp. 716-724

Author(s):

Yan A. Ivanenkov ◽

Renat S. Yamidanov ◽

Ilya A. Osterman ◽

Petr V. Sergiev ◽

Vladimir A. Aladinskiy ◽

...

Keyword(s):

Antibacterial Activity ◽

High Throughput ◽

High Throughput Screening ◽

Large Scale ◽

Antibacterial Agents ◽

Sos Response ◽

Luciferase Assay ◽

Translational Machinery ◽

E Coli ◽

New Class

Background: The key issue in the development of novel antimicrobials is a rapid expansion of new bacterial strains resistant to current antibiotics. Indeed, World Health Organization has reported that bacteria commonly causing infections in hospitals and in the community, e.g. E. Coli, K. pneumoniae and S. aureus, have high resistance vs the last generations of cephalosporins, carbapenems and fluoroquinolones. During the past decades, only few successful efforts to develop and launch new antibacterial medications have been performed. This study aims to identify new class of antibacterial agents using novel high-throughput screening technique. Methods: We have designed library containing 125K compounds not similar in structure (Tanimoto coeff.< 0.7) to that published previously as antibiotics. The HTS platform based on double reporter system pDualrep2 was used to distinguish between molecules able to block translational machinery or induce SOS-response in a model E. coli system. MICs for most active chemicals in LB and M9 medium were determined using broth microdilution assay. Results: In an attempt to discover novel classes of antibacterials, we performed HTS of a large-scale small molecule library using our unique screening platform. This approach permitted us to quickly and robustly evaluate a lot of compounds as well as to determine the mechanism of action in the case of compounds being either translational machinery inhibitors or DNA-damaging agents/replication blockers. HTS has resulted in several new structural classes of molecules exhibiting an attractive antibacterial activity. Herein, we report as promising antibacterials. Two most active compounds from this series showed MIC value of 1.2 (5) and 1.8 μg/mL (6) and good selectivity index. Compound 6 caused RFP induction and low SOS response. In vitro luciferase assay has revealed that it is able to slightly inhibit protein biosynthesis. Compound 5 was tested on several archival strains and exhibited slight activity against gram-negative bacteria and outstanding activity against S. aureus. The key structural requirements for antibacterial potency were also explored. We found, that the unsubstituted carboxylic group is crucial for antibacterial activity as well as the presence of bulky hydrophobic substituents at phenyl fragment. Conclusion: The obtained results provide a solid background for further characterization of the 5'- (carbonylamino)-2,3'-bithiophene-4'-carboxylate derivatives discussed herein as new class of antibacterials and their optimization campaign.

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Recent Advances in 1,3,5-Triazine Derivatives as Antibacterial Agents

Mini-Reviews in Organic Chemistry ◽

10.2174/1570193x17666200129094032 ◽

2020 ◽

Vol 17 (8) ◽

pp. 991-1041

Author(s):

Divya Utreja ◽

Jagdish Kaur ◽

Komalpreet Kaur ◽

Palak Jain

Keyword(s):

Antibacterial Activity ◽

Heterocyclic Compounds ◽

Antibacterial Agents ◽

Rapid Development ◽

Pharmacological Action ◽

Biological Properties ◽

Vast Array ◽

Bacterial Diseases ◽

New Class ◽

Triazine Derivatives

Triazine, one of the nitrogen containing heterocyclic compounds has attracted the considerable interest of researchers due to the vast array of biological properties such as anti-viral, antitumor, anti-convulsant, analgesic, antioxidant, anti-depressant, herbicidal, insecticidal, fungicidal, antibacterial and anti-inflammatory activities offered by it. Various antibacterial agents have been synthesized by researchers to curb bacterial diseases but due to rapid development in drug resistance, tolerance and side effects, there had always been a need for the synthesis of a new class of antibacterial agents that would exhibit improved pharmacological action. Therefore, this review mainly focuses on the various methods for the synthesis of triazine derivatives and their antibacterial activity.

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Changes of Physicochemical Properties of Starch Syrups Recommended for Winter Feeding of Honeybees during Storage

Agriculture ◽

10.3390/agriculture11040374 ◽

2021 ◽

Vol 11 (4) ◽

pp. 374

Author(s):

Teresa Szczęsna ◽

Ewa Waś ◽

Piotr Semkiw ◽

Piotr Skubida ◽

Katarzyna Jaśkiewicz ◽

...

Keyword(s):

Chemical Composition ◽

Physicochemical Properties ◽

Physicochemical Parameters ◽

Storage Temperature ◽

Storage Conditions ◽

Different Temperatures ◽

And Storage ◽

Bee Colonies ◽

Temperature Time ◽

Winter Feeding

The aim of this study was to determine the influence of storage temperature and time on physicochemical parameters of starch syrups recommended for the winter feeding of bee colonies. The studies included commercially available three starch syrups and an inverted saccharose syrup that were stored at different temperatures: ca. 20 °C, 10–14 °C, and ca. 4 °C. Physicochemical parameters of fresh syrups (immediately after purchase) and syrups after 3, 6, 9, 12, 15, 18, 21, and 24 months of storage at the abovementioned temperatures were measured. It was observed that the rate of unfavorable changes in chemical composition of starch syrups and the inverted saccharose syrup, mainly the changes in the 5-hydroxymethylfurfural (HMF) content, depended on the type of a syrup and storage conditions (temperature, time). Properties of tested starch syrups intended for winter feeding of bees stored at ca. 20 °C maintained unchanged for up to 6 months, whereas the same syrups stored at lower temperatures (10–14 °C) maintained unchanged physicochemical parameters for about 12 months. In higher temperatures, the HMF content increased. To date, the influence of this compound on bees has not been thoroughly investigated.

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