Effect of yeast saccharide treatment on nitric oxide accumulation and chilling injury in cucumber fruit during cold storage

The effects of a saccharide fraction prepared from yeast cell walls on chilling injury and endogenous nitric oxide (NO) generation in cucumbers and the role of NO in yeast saccharide (YS)-induced cold tolerance of the fruit during postharvest storage, were investigated. Chilling injury index, malondialdehyde (MDA) content, and ion leakage of fruit treated with 0.5 g/L YS were significantly reduced as compared with those of control fruit stored at 4 °C, showing that YS treatment may reduce chilling injury in cucumber. Moreover, treatment with YS triggered a marked increase in endogenous NO levels. An NO scavenger and NO synthase inhibitors not only diminished YS-triggered NO generation but also suppressed YS-enhanced cold tolerance. Together, our results indicate that YS could have potential postharvest application for reducing chilling injury in cucumber fruit. Furthermore, we found that YS-induced cold tolerance is linked with the induction of endogenous NO accumulation.

► Yeast saccharide (YS) reduces MDA content, ion leakage and the chilling index in cold-stored cucumbers.
► YS triggers a marked increase in NO levels in cucumber fruit.
► An NO scavenger and NO synthase inhibitors diminish YS-enhanced cold tolerance.
► YS stimulates cold tolerance in cucumber fruit by triggering endogenous NO production.