Effects of latitude and weather conditions on proanthocyanidins in berries of Finnish wild and cultivated sea buckthorn (Hippophaë rhamnoides L. ssp. rhamnoides)

• Proanthocyanidins contents were studied in Finnish sea buckthorn for several years.
• The berries from south and north Finland were separated in a PLS-DA model.
• The amount of proanthocyanidins (PAs) were higher in the northern samples.
• Temperature sum and length of growth season had negative impact on total PAs in north.
• Same weather variables had positive impact on less abundant PA oligomers.

Sea buckthorn (Hippophaë rhamnoides ssp. rhamnoides) of varieties ‘Terhi’ and ‘Tytti’ and one of wild origin were cultivated in southern and northern Finland, harvested during 2007–2013. Proanthocyanidins (PAs) were analyzed with HILIC UPLC–ESI-MS. The southern and northern samples were separated in the partial least squares discriminant analysis model (four factors, R2 0.75, Q2 0.70). The total PAs were more abundant in berries from the north (610–970 mg/100 g DW) than in those from the south (340–450 mg/100 g DW) (p < 0.05). In northern Finland, the length of the growth season as well as the temperature sum and radiation sum of the growth season until harvest were negatively correlated with the total PAs in all the samples but positively with PA oligomers in ‘Tytti’ and ‘Terhi’. In southern Finland no respective correlations were seen. ‘Terhi’ and ‘Tytti’ had different trends in the content of total PA and oligomers in overripe stages.