Advances on research in the use of agro-industrial waste in biosurfactant production.

Biosurfactants are amphiphilic molecules produced by a variety of microorganisms, including bacteria, yeast and filamentous fungi. Unlike chemically synthesized surfactants, biosurfactants present advantages, such as biodegradability, low toxicity, high selectivity and activity under extreme temperature, pH and salinity conditions, as well as a low critical micelle concentration. Moreover, they can be produced from agro-industrial waste and renewable sources. Their structural diversity and functional properties mean that they have potential applications in various industrial processes as wetting agents, dispersants, emulsifiers, foaming agents, food additives and detergents, as well as in the field of environmental biotechnology. However, opportunities for their commercialization have been limited due to the low yields obtained in the fermentation processes involved in their production as well as the use of refined raw materials, which means higher cost in production. In an attempt to solve these limitations on the commercialization of biosurfactants, various research groups have focused on testing the use of inexpensive alternative sources, such as agro-industrial waste, as substrates for the production of different biosurfactants. In addition to enabling the economical production of biosurfactants, the use of such waste aims to reduce the accumulation of compounds that cause environmental damage. This review shows advances in biosurfactant production carried out using different waste materials or by-products from agro-industrial activities.

6-Substituted 2-(N-trifluoroacetylamino)imidazopyridines induce cell cycle arrest and apoptosis in SK-LU-1 human cancer cell line.

A series of 6-substituted 2-(N-trifluoroacetylamino)imidazopyridines have been synthesized and their bioactivities were evaluated. Compounds 6a, 6c, and 11a were the most active compounds with modest cytotoxic activity against six human cancer cell lines U251 (glioma), PC-3 (prostate), K-562 (leukemia), HCT-15 (colon), MCF7 (breast) and SK-LU-1 (lung). The cell cycle analysis showed that compounds 6a, 6c, and 11a induce a G2/M phase cell cycle arrest on SK-LU-1 cell line where inhibition of CDK-1 and CDK-2 may be implicated.

Synthesis and cytotoxic activity of 2-methylimidazo[1,2-a]pyridine- and quinoline-substituted 2-aminopyrimidine derivatives.

A series of 2-methylimidazo[1,2-a]pyridine- and quinoline-substituted 2-aminopyrimidines derivatives were synthesized using a convenient synthetic route. We evaluate the isosteric replacement of methyl groups in 4-(2-methylimidazo[1,2-a]pyridin-3-yl)-N-p-tolylpyrimidin-2-amine (compound 1) by trifluoromethyl groups and the isosteric substitution of the 2-methylimidazo[1,2-a]pyridin-3-yl scaffold by quinolin-4-yl or quinolin-3-yl moieties. The replacement of hydrogen by fluorine does not affect notably the cytotoxic activity and CDK inhibitor activity in this series. Quinolin-4-yl-substituted compound, 8, presents cytotoxic activity and is most effective and selective against CDK1/CycA than against CDK2/CycB. Compound 11, which has a quinolin-3-yl moiety is CDK inhibitor but presents null cytotoxic activity. Quinolin-4-yl-substituted compounds constitute a new lead of cytotoxic and CDK inhibitor compounds from which more compelling and selective inhibitors can be designed.