Influence of pasteurization on antioxidant and in vitro anti-proliferative effects of jambolan (Syzygium cumini (L.) Skeels) fruit pulp

• Pasteurization led to an increase on total phenols and flavonoids content in jambolan pulp.
• Anthocyanins content was reduced when compared with jambolan pulp without thermal treatment.
• Jambolan pulp without pasteurization showed inhibition for melanoma lineage and resistant ovary.
• Pasteurized jambolan pulp revealed cytostatic activities for kidney lineages and ovary.

Here we analyze jambolan pulp phenolic compounds in order to establish a correlation with antioxidant and in vitro anti-proliferative effects, both before and after pasteurization. Total levels of phenolic compounds, flavonoids and anthocyanins were quantified using UV–vis techniques. Major phenolic compounds were identified by standard compound co-injection in HPLC-DAD/UV–vis. Antioxidant activity was measured by radical scavenging ability, as determined by DPPH assay. In vitro anti-proliferative activity was determined against nine human tumour cell lines using the methodology described by the Developmental Therapeutics Program at NCI/NIH. Pasteurization led to an increase in the levels of total soluble solids (6.7%), phenolic compounds (7.2%) and flavonoids (16.4%). Anthocyanin content was largely preserved (91%) when compared with pulp without treatment. S. cumini preserved 56% of its original antioxidant activity after pasteurization, while thermal treatment revealed cytostatic activity in kidney (786-0) and ovary (OVCAR-3) lineages. Therefore, pasteurization can be applied successfully to S. cumini pulp.