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Biomedical subjects

M Vanhaelen

Publications and source records attributed to M Vanhaelen.

13 recordsLinked to original sources
PubMed1978

High-performance liquid chromatography determination of potential content of vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) in resins, oils, dry concentrates and multivitamin formulations.

The determination of potential vitamin D concentrations in raw materials and in multivitamin formulations by high-performance liquid chromatography is reported. Simple experimental conditions allow the rapid separation of the vitamins from their respective pro- and pre-vitamins, from their irradiation side-products and from some of their overirradiation products. Vitamin extraction is performed directly from dry concentrates, tablets and capsules, without saponification; all procedures are carried out at room temperature so as to preserve the ratio of vitamin D and pre-vitamin D present in the prepatation. The relative standard deviation is less than 1.5%.

Cholecalciferol↗
PubMed1978

Volatile constituents of Trichothecium roseum.

In the course of investigation of Trichothecium roseum (Fungi Imperfecti) for its attractancy against Tyrophagus putrescentiae (cheese mite), the twenty following volatile compounds produced at a very low concentration by the microfungus were identified by gc, gc/ms, gc/c.i.ms and tlc: 3-methyl-1-butanol, 3-octanone, 1-octen-3-one, 3-octanol, octa-1,5-dien-3 one, 1-octen-3-ol, 6-methyl-5-hepten-2-ol, octa-1,5-dien-3 ol, furfural, linalool, linalyl acetate, terpineol (alpha and beta) citronellyl acetate, nerol, citronellol, phenylacetaldehyde, benzyl alcohol geranyl acetate, 1-phenyl ethanol and nerolidol. Octa-1,5-dien-3-ol and octa-1,5-dien-3-one have not been previously isolated from fungi; octa-1,5-dien-3-ol is the most potent attractant amount the volatile compounds detected by gc.

Aldehydes↗
PubMed1978

Cis-and trans-octa-1,5-dien-3-ol, new attractants to the cheese mite Tyrophagus putrescentiae (Schrank) (Acarina, Acaridae) idintified in Trichothecium roseum (Fungi Imperfecti).

The volatile materials emitted by Trichothecium roseum (Fungi Imperfecti) at a very low concentration are strong attractants for Tyrophagus putrescentiae (Schrank, 1781) (Acarina, Acardae). The identification of cis- and trans-octa-1,5-dien-3-ol, the main attractant constituents of these volatile materials, was performed by spectroscopic methods (GC/MS and NMR) on a microsample (less than 100 micrograms) isolated by a new pre-concentration method. Although this unsaturated alcohol has only been found in Trichothecium roseum and in a Rhodophyta, it may be present in other microfungi and in fungi and may be implicated in the ecological process.

Animals↗