Abstract
To prepare tissues for analysis of NAD+, NADH, NADP+, and NADPH, common practice is to freeze samples in liquid nitrogen, often followed by freeze-drying, before extraction in HCl or NaOH. With cucumber (Cucumis sativus L.) cotyledons, prefreezing in liquid nitrogen or slower freezing to −20°C yielded substantially lower values for NADH and NADPH than obtained from samples homogenized immediately in acid or base. Freeze-drying after freezing in liquid nitrogen generally caused even lower values of those coenzymes. We suggest that direct extraction is more likely to yield accurate results with cotyledons and other plant parts.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Graham J. S., Hawker J. S. Measurement of nicotinamide adenine dinucleotide & nicotinamide adenine dinucleotide phosphate in tomato leaves. Plant Physiol. 1962 Nov;37(6):765–767. doi: 10.1104/pp.37.6.765. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Muto S., Miyachi S. Light-induced conversion of nicotinamide adenine dinucleotide to nicotinamide adenine dinucleotide phosphate in higher plant leaves. Plant Physiol. 1981 Aug;68(2):324–328. doi: 10.1104/pp.68.2.324. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ogren W. L., Krogmann D. W. Studies on pyridine nucleotides in photosynthetic tissue. Concentrations, interconversions, and distribution. J Biol Chem. 1965 Dec;240(12):4603–4608. [PubMed] [Google Scholar]