Isolation and Purity Assessment of Membranes from Norway Spruce.

Gaining membrane vesicles from different plant species and tissue types is crucial for membrane studies. Membrane vesicles can be used for further purification of individual membrane types, and, for example, in studies of membrane enzyme activities, transport assays, and in proteomic analysis. Membrane isolation from some species, such as conifers, has proved to be more difficult than that of angiosperm species. In this paper, we describe steps for isolating cellular membranes from developing xylem, phloem, and lignin-forming tissue-cultured cells of Norway spruce, followed by partial enrichment of plasma membranes by aqueous polymer two-phase partitioning and purity analyses. The methods used are partially similar to the ones used for mono- and dicotyledonous plants, but some steps require discreet optimization, probably due to a high content of phenolic compounds present in the tissues and cultured cells of Norway spruce.

Assessment of calcium and zinc accumulation in cultivated and wild apples.

BACKGROUND: Apple is one of the staple fruits worldwide which are a good source of mineral nutrients. However, little is known about genetic variation for mineral nutrition in apple germplasm. In this study, the calcium and zinc contents in mature fruits of 378 apple cultivars and 39 wild relatives were assessed. Mineral concentrations were quantified using flame atomic absorption spectroscopy (FAAS). RESULTS: Both calcium and zinc accumulation showed great variation among accessions tested. Overall, wild fruits were significantly richer in zinc than cultivated fruits, while the average concentration of calcium was similar between cultivated and wild fruits. The difference in zinc concentration between wild and cultivated fruits may be an indirect result of artificial selection on fruit characteristics during apple domestication. Moreover, calcium concentration in fruit showed a decreasing trend throughout fruit development of apple, while zinc concentration in fruit displayed a complex variation pattern in the late stages of fruit development. CONCLUSION: The finding of a wild genetic variation for fruit calcium and zinc accumulation in apple germplasm could be helpful for future research on genetic dissection and improvement of calcium and zinc accumulation in apple fruit. © 2017 Society of Chemical Industry.