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2.
Chimia (Aarau) ; 75(11): 957-966, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34798918

RESUMEN

Collaborations between academia and industry are vital for modern industrial research and development projects, combining the best of both worlds to develop sustainable chemical processes. Herein we summarize a number of successful cooperations between DSM Nutritional Products and Swiss academic institutions that have been carried out over approximately the past decade. A wide variety of reactions and processes have been investigated with experts located in Switzerland. New synthetic routes, chemical transformations and reactor concepts have been developed to produce industrially relevant compounds. Additionally the scope of known catalytic systems has been probed and new catalysts showing improved selectivity have been designed, synthesized and tested. We describe how the research was supported by DSM, the parallel in-house investigations and also how the projects were continued and further developed.


Asunto(s)
Industrias , Investigación , Catálisis , Suiza , Universidades
3.
Chimia (Aarau) ; 75(9): 757-765, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526181

RESUMEN

A modern trend to carbon dioxide neutral production processes is based on renewable raw materials derived from sugars. Herein, an overview on modern approaches to fine chemicals for the nutritional industry is presented. In comparison to the traditional fossil-fuel-based processes the development of sustainable alternative transformations is necessary to enable the full potential of the new sustainable feedstocks.


Asunto(s)
Combustibles Fósiles , Azúcares , Industrias
4.
Nutrients ; 13(2)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670165

RESUMEN

This study applied linear programming using a Dutch "model diet" to simulate the dietary shifts needed in order to optimize the intake of vitamin D and to minimize the carbon footprint, considering the popularity of the diet. Scenarios were modelled without and with additional fortified bread, milk, and oil as options in the diets. The baseline diet provided about one fifth of the adequate intake of vitamin D from natural food sources and voluntary vitamin D-fortified foods. Nevertheless, when optimizing this diet for vitamin D, these food sources together were insufficient to meet the adequate intake required, unless the carbon emission and calorie intake were increased almost 3-fold and 2-fold, respectively. When vitamin D-fortified bread, milk, and oil were added as options to the diet, along with increases in fish consumption, and decreases in sugar, snack, and cake consumption, adequate intakes for vitamin D and other nutrients could be met within the 2000 kcal limits, along with a relatively unchanged carbon footprint. Achieving vitamin D goals while reducing the carbon footprint by 10% was only possible when compromising on the popularity of the diet. Adding vitamin D to foods did not contribute to the total carbon emissions. The modelling study shows that it is impossible to obtain adequate vitamin D through realistic dietary shifts alone, unless more vitamin D-fortified foods are a necessary part of the diet.


Asunto(s)
Huella de Carbono , Dieta , Alimentos Fortificados , Necesidades Nutricionales , Vitamina D/administración & dosificación , Dióxido de Carbono/análisis , Ingestión de Alimentos , Abastecimiento de Alimentos , Gases de Efecto Invernadero , Humanos , Modelos Lineales , Países Bajos , Valor Nutritivo
5.
Angew Chem Int Ed Engl ; 51(52): 12960-90, 2012 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-23208776

RESUMEN

The discovery of vitamins as essential factors in the diet was a scientific breakthrough that changed the world. Diseases such as scurvy, rickets, beriberi, and pellagra were recognized to be curable with an adequate diet. These diseases had been prevalent for thousands of years and had a dramatic impact on societies as well as on economic development. This Review highlights the key achievements in the development of industrial processes for the manufacture of eight of the 13 vitamins.


Asunto(s)
Disciplinas de las Ciencias Naturales/historia , Vitaminas/historia , Ácido Ascórbico/síntesis química , Ácido Ascórbico/historia , Ácido Ascórbico/metabolismo , Biotina/síntesis química , Biotina/historia , Biotina/metabolismo , Historia del Siglo XX , Humanos , Ácido Pantoténico/síntesis química , Ácido Pantoténico/historia , Ácido Pantoténico/metabolismo , Piridoxina/síntesis química , Piridoxina/historia , Piridoxina/metabolismo , Riboflavina/síntesis química , Riboflavina/historia , Riboflavina/metabolismo , Tiamina/síntesis química , Tiamina/historia , Tiamina/metabolismo , Vitamina A/síntesis química , Vitamina A/historia , Vitamina A/metabolismo , Vitamina E/síntesis química , Vitamina E/historia , Vitamina E/metabolismo , Vitaminas/síntesis química , Vitaminas/metabolismo
6.
Chimia (Aarau) ; 65(6): 420-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21797172

RESUMEN

In this review, synthetic strategies and the development of environmentally benign methods for the production of economically important vitamins, carotenoids, and nutraceuticals used as food and feed supplements are illustrated by selected examples. The application of efficient catalytic transformations in multi-step chemical syntheses of such natural products enables technically feasible and cost-effective processes. For the preparation of fat-soluble (isoprenoid) vitamins A and E and the water-soluble vitamin (+)-biotin, homogeneous metal catalysis, including enantioselective transformations, heterogeneous and enzymatic catalysis serve as key methodologies. In the area of carotenoids, general building concepts and coupling methods for the total synthesis of beta-carotene and astaxanthin are discussed. Biotechnological methods and isolation from natural sources are also employed successfully, as exemplified for the xanthophyll lutein and the antioxidant (-)-epigallocatechin gallate. Lastly, key steps of the chemical synthesis of the polyphenol resveratrol are highlighted.


Asunto(s)
Industria Química/métodos , Suplementos Dietéticos , Fenómenos Fisiológicos de la Nutrición , Animales , Humanos
7.
Chemistry ; 16(37): 11420-31, 2010 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-20715200

RESUMEN

Two Pt(IV) and two Pt(II) complexes containing a 2,2'-bipyridine ligand were treated with a short DNA oligonucleotide under light irradiation at 37°C or in the dark at 37 and 50°C. Photolysis and thermolysis of the Pt(IV) complexes led to spontaneous reduction of the Pt(IV) to the corresponding Pt(II) complexes and to binding of Pt(II) 2,2'-bipyridine complexes to N7 of guanine. When the reduction product was [Pt(bpy)Cl(2)], formation of bis-oligonucleotide adducts was observed, whereas [Pt(bpy)(MeNH(2))Cl](+) gave monoadducts, with chloride ligands substituted in both cases. Neither in the dark nor under light irradiation was the reductive elimination process of these Pt(IV) complexes accompanied by oxidative DNA damage. This work raises the question of the stability of photoactivatable Pt(IV) complexes toward moderate heating conditions.


Asunto(s)
2,2'-Dipiridil/química , Aductos de ADN/síntesis química , Compuestos Organoplatinos/química , Fotólisis , Animales , Secuencia de Bases , Aductos de ADN/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hidrolasas Diéster Fosfóricas/metabolismo , Venenos de Serpiente/enzimología , Temperatura
8.
Chem Soc Rev ; 36(5): 759-69, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17471400

RESUMEN

Silver acetylides are among the oldest organometallics known; however, their applications in organic chemistry remained scarce until very recently. Indeed, several reactions involving silver salts as catalyst or silver acetylides have been reported in the past five years. The extreme mildness and very low basicity of these nucleophilic reagents nicely complement the behavior of other alkynyl metals, rendering them very useful in various transformations, especially in the synthesis of complex molecules. Silver acetylides are now seen as promising tools in organic chemistry. This critical review focuses on this emerging field, and, with emphasis on mechanistic aspects, cover the synthesis of silver acetylides, their applications in organic chemistry and reactions involving silver salts as catalysts where silver acetylides are probable intermediates.

9.
Chemistry ; 13(14): 3980-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17295379

RESUMEN

Three 2,2'-bipyridine (2,2'-bpy) complexes of Pt(IV) have been synthesized, characterized by X-ray crystallography, and their solution behavior in D(2)O studied by (1)H NMR spectroscopic analysis: mer-[PtCl(3)(2,2'-bpy)(MeNH(2))]ClH(2)O (4), trans-[PtCl(2)(2,2'-bpy)(MeNH(2))(2)]Cl(2) (5), and trans-[Pt (2,2'-bpy)(MeNH(2))(2)(OH)(2)]Cl(2) (6; MeNH(2)=methylamine). Complexes 4 and 5 undergo hydrolysis of the Cl(-) ions, both in the dark and daylight, as evident from a drop in the pH value. Two solvolysis products were detected in the case of 4, which is indicative of species with equatorial and axial OH(-) groups. The hydrolysis reaction of 5 implies that an axial Cl(-) group is replaced by an OH(-) moiety; in contrast, 6 remains virtually unaffected. Ordinary daylight, in particular irradiation with a 50-W halogen lamp, initially causes ligand-isomerization processes, which are followed by the reduction of 4 and 5 to Pt(II) species. This reduction of 4 and 5 is accompanied by the formation of hypochlorous acid, as demonstrated qualitatively in the decoloration test of indigo, and loss of MeNH(2), which is particularly pronounced in the case of 5. The formation of Pt(II) compounds is established on the basis of the J coupling constants of (195)Pt with selected (1)H NMR resonances. The results obtained herein are possibly also relevant to the chemistry of Cl-containing Pt(IV) antitumor agents and their reactions with DNA.


Asunto(s)
2,2'-Dipiridil/química , Cloro/química , Ácido Hipocloroso/química , Luz , Metilaminas/química , Compuestos de Platino/química , Isomerismo , Espectroscopía de Resonancia Magnética , Estructura Molecular , Oxidación-Reducción
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