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3.
Biodes Res ; 5: 0008, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37849455

RESUMO

The growth of biotechnology in recent decades and the dual-use nature of most bioscience research are making their misuse, or accidental misuse or release, more likely and present as threats to biosecurity. A proactive approach is through educating the next generation of scientists to be more security conscious. However, current educational and professional programs in biosecurity are lacking. In this perspective, we recommend that biosecurity educational opportunities should be implemented and expanded for undergraduate and graduate students who will likely use one or more methods in the field of biotechnology. We then propose that biosecurity education is a key factor in a path toward sustainable and safe research. Finally, a set of 17 biosecurity competencies organized into 6 distinct themes is outlined.

4.
Carbohydr Res ; 521: 108647, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36029635

RESUMO

Sucralose differs from sucrose only by virtue of having three Cl groups instead of OH groups. Its intriguing features include being noncaloric, noncariogenic, ∼600 times sweeter than sucrose, stable at high temperatures/acidic pH's, and void of disagreeable aftertastes. These properties are attractive as food additive, one of which is as hydrogel obtainable via the technique of molecular gelation using a sucralose-derived low-molecular weight gelator (LMWG). Such hydrogels are highly responsive to external stimuli like temperature, because the LMWGs self-assemble via non-covalent interactions and could thus be utilized in applications like control-release. We found that sucralose to be unreactive under lipase biocatalysis, unlike sucrose. Hence, the aim of this work was (i) to use computational simulations to further understand sucralose's lack of enzymatic reactivity and (ii) to synthesize the sucralose-based amphiphiles using conventional chemical synthesis and systematically study their tendency towards hydrogelation. Sucrose and sucralose were docked with a high-resolution atomic structure of lipase B from Candida antarctica, modeling the esterification transition state with an active site serine. In extended molecular dynamics simulations, sucrose remained in the active site due to multiple sugar-protein hydrogen bonds. The oxygen-to-chlorine substitutions in sucralose disrupted this hydrogen bonding network. Consistent with observed lack of enzymatic conversion, in multiple simulations, sucralose would rapidly dissociate from the active site. The sucralose-based LMWGs were subsequently synthesized using base-catalyzed conventional chemical synthesis. Three of the sucralose-based amphiphiles (SL-5, SL-6 and SL-7) proved to be successful hydrogelators. The gelators also showed the ability to gel selected beverages. The LMWGs gelled quantities of water and beverage up to 71 and 55 times their weight, respectively, and remain thermally stable up to 144 °C.


Assuntos
Hidrogéis , Lipase , Biocatálise , Cloro , Esterificação , Aditivos Alimentares , Hidrogéis/química , Oxigênio , Serina , Sacarose/análogos & derivados , Sacarose/química , Água
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