SYNTHESIS AND ANTIMICROBIAL EVALUATION OF SOME NEW OXAZINE DERIVATIVES DERIVED FROM COUMARINYL CHALCONES

A series of novel substituted 3-(2-amino-6-phenyl-6H-1,3-oxazin-4-yl)-2H-chromen-2-ones(AO1-AO10) was synthesized upon refluxing ethanolic solution of substituted 3-cinnamoyl-2H chromen-2-one with urea in presence of 20 % NaOH. The intermediate chalcones, substituted 3-cinnamoyl-2H-chromen2-ones, were synthesized by condensing 3-acetyl coumarin with various substituted benzaldehydes in presence of 20 % NaOH. The structures of the final synthesized compounds were characterized by UV, IR, 1 H NMR and mass spectra. The antibacterial activity of the synthesized compounds was estimated by tube dilution method. The turbidity was observed for the synthesized compounds. Few compounds showed promising minimum inhibitory concentration by tube dilution method.

Physicochemical, antioxidant, and antibacterial properties of heattreated edible mushroom extracts

This study describes the thermal effect on physicochemical properties, phenolic content, as well as antioxidant and antibacterial activity of edible mushroom extracts (EME) from Agaricus brasiliensis, Ganoderma lucidum, and Pleurotus ostreatus in aqueous-ethanolic solution. The heating of EME resulted in a reduction of pH and total soluble solids and changes in color values in time dependence (p < 0.05). In addition, total phenolic and flavonoid contents, antiradical activity (DPPH• and ABTS•+ inhibition), and reducing power were enhanced with increasing temperature (90 °C, for 6 h), mainly in the P. ostreatus extract (p < 0.05). In contrast, the results indicate that high temperatures reduced (p < 0.05) the antibacterial effect against all pathogens tested. In conclusion, the thermal treatment affected physicochemical and antibacterial properties of EME and enhanced phenolic composition and antioxidant activity.

Shoot Girdling Improves Rooting Performance of Kalamata Olive Cuttings by Upregulating Carbohydrates, Polyamines and Phenolic Compounds

Girdling (a ring of bark approximately 5 mm wide) was applied on olive mother plants to investigate its effect on the rooting ability of cuttings. Treatment was applied in autumn and in spring. The cuttings were then immersed for 5 s into 2000 mg L−1 indole-3-butyric acid (IBA) in a 45% v/v ethanolic solution. Thirty days after girdling, cuttings were taken from girdled and control shoots from the part just above the girdle zone (basal), as well as from the part right above (middle). The base of the cuttings was collected, and the concentration of polyamines, phenolic compounds and soluble carbohydrates was determined. Girdling enhanced the rooting performance of the cuttings, while autumn proved to be a better season for rooting compared to spring. Girdling positively affected the concentration of all the measured parameters. The main characteristics of autumn cuttings were the high levels of glucose, mannitol, free and total polyamines, hydroxytyrosol, tyrosol, verbascoside, oleuropein, quercetin and luteolin. The cuttings taken from the middle part of the girdled shoot exhibited high sucrose, glucose, mannitol, free polyamines, hydroxytyrosol, luteolin-7-glucoside, total phenols and flavanol concentrations. Nonetheless, further research is needed in order to draw conclusions on the overall efficiency of girdling on inducing rooting of olive cuttings.

Organosilanes in wood protection – chemical analysis of wood and cellulose treated with MTMOS

Organosilanes in wood protection – chemical analysis of wood and cellulose treated with MTMOS. The paper presents the results of methyltrimethoxysilane (MTMOS) reactivity with Scots pine wood and cellulose. The lignocellulosic material after treatment with ethanolic solution of MTMOS was analysed using instrumental methods – atomic absorption spectrometry (AAS) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). The analysis of silicon concentration in treated material indicated the presence of silane in structure of wood and cellulose. The bands characteristic of vibrations of the silicon-carbon and silicon-oxygen originating from MTMOS molecule were observed in the spectra of modified materials, which confirmed the reactivity of silane with wood and cellulose. Moreover, the chemical analysis indicated that MTMOS exhibited higher reactivity to cellulose than to pine wood.

Crystal structures of 6-cyclopropyl-1,3-diphenylfulvene and 6-(2,3-dimethoxynaphthyl)-1,3-diphenylfulvene

The title compounds, 6-cyclopropyl-1,3-diphenylfulvene, C21H18, [systematic name: 5-(cyclopropylmethylidene)-1,3-diphenylcyclopenta-1,3-diene], 1, and 6-(2,3-dimethoxynaphthyl)-1,3-diphenylfulvene, C30H24O2, {systematic name: 5-[(3,4-dimethoxynaphthalen-2-yl)methylidene]-1,3-diphenylcyclopenta-1,3-diene}, 2, were prepared from 1,3-diphenylcyclopentadiene, pyrrolidine, and the corresponding aldehydes in an ethanolic solution. Each structure crystallizes with one molecule per asymmetric unit and exhibits the alternating short and long bond lengths typical of fulvenes. A network of C—H...C ring interactions as well as C—H...O interactions is observed, resulting in the compact packing found in each structure.

Chemical Biopreservative Effects of Red Seaweed on the Shelf Life of Black Tiger Shrimp (Penaeus monodon)

Hypnea musciformis (HM) and Acanthophora muscoides (AM) red seaweeds were evaluated for their antioxidant properties and efficacy to extend the chemical shelf life of black tiger shrimp (Penaeus monodon) during 14-daystorage. Treated shrimp were soaked in five percent ethanolic solution with 500 µg/mL of AM or HM powder for 30 min. HM had more phenols and flavonoids, increased radical scavenging activity, and greater H2O2 reducing power than AM in vitro. Biochemical quality indicators were significantly higher in the control group, followed by HM- and AM-treated samples during storage. On day 14 of storage, controls contained significantly higher amounts of biogenic amines than HM- or AM-treated samples. The shelf life of chilled stored shrimp increased due to the presence of compounds of butylated hydroxytoluene, sulfurous acid, heptadecane, mono (2-ethylhexyl), and 1,2-propanediol found in AM extract and sulfurous acid and 1,2-propanediol found in HM extract. A control group was soaked in the same ethanolic solution as treated samples without algae powder for 30 min. Each group was kept ice-cold during the soaking period. The results obtained demonstrate the usefulness of two seaweed extracts, Hypnea musciformis and Acanthophora muscoides, combined with ice by decreasing the formation of toxic biogenic amines in shrimp, enhancing its shelf life during ice storage.

Reactivity of (3-aminopropyl)trimethoxysilane with cellulose

Reactivity of (3-aminopropyl)trimethoxysilane with cellulose. The paper presents the results of tests for the reactivity of (3-aminopropyl)trimethoxysilane (APTMOS) with cellulose. The cellulose was treated with aqueous ethanolic solution of silane in two concentration: 5% and 20%. The reactivity of APTMOS with cellulose was analysed using instrumental methods: attenuated total reflectance Fourier transform infrared spectroscopy, atomic absorption spectrometry and elemental analysis. In the FTIR spectra of silane-treated cellulose, the bands of Si-O, Si-C and N-H bonds were detected. The analysis of silicon and nitrogen concentration in treated cellulose confirmed the presence of silane in cellulose structure. The presented results indicate that APTMOS forms chemical bonds with cellulose.

A reaction of [3-(2-aminoethylamino)propyl]trimethoxysilane with wood and cellulose – chemical analyses

A reaction of [3-(2-aminoethylamino)propyl]trimethoxysilane with wood and cellulose – chemical analyses. The paper presents tests results for [3-(2-aminoethylamino)propyl]trimethoxysilane (AATMOS) reactivity with cellulose and Scots pine wood. The tested material was treated with ethanolic solution of aminosilane and analyzed using instrumental methods, including elemental analysis, atomic absorption spectrometry and infrared spectroscopy. The results of the chemical analysis indicated that [3-(2-aminoethylamino)propyl]trimethoxysilane exhibited reactivity with both cellulose and pine wood. In addition, AATMOS-treated cellulose showed a higher content of silicon and nitrogen and more significant changes in FTIR spectra than the treated wood, suggesting that AATMOS showed a higher reactivity to cellulose than to wood.

Polycarbonate Microchip Containing CuBTC-Monopol Monolith for Solid-Phase Extraction of Dyes

In the present study, preparation of CuBTC-monopol monoliths for use within the microchip solid phase extraction was undertaken through a 20-min UV lamp-assisted polymerization for 2,2-dimethoxy-2-phenyl acetophenone (DMPA), butyl methacrylate (BMA), and ethylene dimethacrylate (EDMA) alongside inclusion of the porogenic solvent system (1-propanol and methanol (1 : 1)). The resultant coating underwent coating using CuBTC nanocrystals in ethanolic solution of ethanolic solution of 1,3,5-benzenetricarboxylic acid (H3BTC, 10 mM) and 10 mM copper(II) acetate Cu(CH3COO)2. This paper reports enhanced extraction, characterization, and synthesis studies for porous CuBTC metal organic frameworks that are marked by different methods including SEM/EDAX analysis, atomic force microscopy (AFM), and Fourier-transform infrared spectroscopy (FT-IR). The evaluation of the microchip’s performance was undertaken as sorbent through retrieval of six toxic dyes (anionic and cationic dyes). Various parameters (desorption and extraction step flow rates, volume of desorption solvent, volume of sample, and type of desorption solvent) were examined to optimize dye extraction using fabricated microchips. The result indicated that CuBTC-monopol monoliths were permeable with the ability of removing impurities and attained high toxic dye extraction recovery (83.4–99.9%). The assessment of reproducibility for chip-to-chip was undertaken by computing the relative standard deviations (RSDs) of the six dyes in extraction. The interbatch and intrabatch RSDs ranged between 3.8 and 6.9% and 2.3 and 4.8%. Such features showed that fabricated CuBTC-monopol monolithic disk polycarbonate microchips have the potential of extracting toxic dyes that could be utilized for treating wastewater.