The effects of different solvents, temperature conditions, solvent-solid ratios and particle sizes on solid-solvent extraction of the total phenolics, proanthocyanidins and flavonoids herein also referred to as antioxidant from pomegranate marc peel (PMP) was studied. Water, methanol, ethanol, acetone, and ethyl acetate extraction efficiencies at extraction times of 0.17 to 10 min, extraction t...

Abstract This study aims to assess kinetic modelling of the solid–liquid extraction process total polyphenolic compounds (TPC) from apple pomace (AP). In this regard, we investigated effects temperature and solvent (i.e. water, ethanol, acetone) on TPC over various periods. The highest yield 11.1 ± 0.49 mg gallic acid equivalent (GAE)/g db (dry basis) was achieved with a mixture 65% acetone–35%...

The asymmetric syntheses of two new spirolactones prepared in optically pure form from L-3-nitrotyrosine are described. The key step, an oxidative spiroannulation, was carried out on the optically active phenols 11a and 11b and afforded the new spirolactones 5a and 5b in 85% and 83% yields, respectively, as mixtures (3:1 dr) of diastereomers. The major diastereomers from these mixtures could be...

In the present investigation natural phenolic antioxidants were extracted from Jojoba seed waste. Samples of defatted jojoba meal (JSM), detoxified residue (DMR) and shell (JSH) subjected to extraction by using various solvents: 70/30 (vol/vol) ethanol/water, methanol/water 60/40 acetone/water. Total phenolics content (TPC) is measured according Folin-Ciocalteu method. In addition, solvent extr...

The biosynthetic utilization of laccase/mediator system is problematic because the use of organic cosolvent causes significant inhibition of laccase activity. This work explored how the organic cosolvent impacts on the laccase catalytic capacity towards 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) in aqueous solution. Effects of acetone on the kinetic constants of laccase were ...

The present investigation of crude extracts from leaf, seed coat and stem of cardiospermum halicacabum L. in different solvent, were subjected to phytochemical and antibacterial screening against the selected Gram positive and Gram negative bacteria. The phytochemical solvent extracts were used for screening and antibacterial activity, were analysed. The Phytochemical studies indicate that the ...

In this paper, a simple dispersive liquid-liquid microextraction for the extraction and pre-concentration of formaldehyde in seawater samples followed with spectrophotometric is proposed. Formaldehyde was derivatized in situ with acetyl acetone in the presence of ammonium acetate in a single step. Then it was collected into a mixture of ethanol (disperser solvent) and chloroform (extracting...

A practical and green method for the synthesis of 5H-dibenzo[b,i]xanthene-tetraones and spiro[dibenzo[b,i]xanthene-13,3'-indoline]-pentaones by the condensation of 2-hydroxynaphthalene-1,4-dione with aldehydes or isatins, respectively, in the presence of a catalytic amount of cellulose sulfuric acid (CSA) under solvent-free conditions at 100 °C is described. The significant features of this pro...

Computerized dynamic assessment has been proposed as a solution to the practicality issues involved in ordinary dynamic assessment procedures. However, most of computerized dynamic assessment studies have addressed receptive skills (i.e., reading and listening). Responding to the scarcity of CDA studies of productive skills, the present study was an attempt to design and implement a computerize...