Evaluation of processing methods and harvest timings for the efficient extraction of Syzygium formosum

Syzygium formosum has been traditionally used in Vietnam as a folk medicine for treating skin and respiratory diseases.With the recent recognition of its beneficial effects such as anticancer, antioxidant, and anti-inflammatory properties, there is an increasing interest in industrial extraction of its bioactive compounds, such as triterpenoids and flavonoids.In this study, the extraction efficiencies of S. formosum were analyzed by extraction methods and harvest timings.Firstly, it was found that distilled water treatment substantially eliminated almost all flavonoids, suggesting that minimal pretreatment is important to preserve both triterpenoids and flavonoids.Secondly, extractions with 70% ethanol at both lab and pilot scales effectively yielded more than 70% of triterpenoids and flavonoids from S. formosum.Lastly, to investigate the seasonal variation in phytochemicals, extracts from the leaves of S. formosum harvested in April, August, October, and December in Vietnam were analyzed.It was revealed that seasons with lower temperatures led to higher concentrations of triterpenoids and flavonoids.Specifically, December was found to be optimal for obtaining high concentrations of triterpenoid and October for flavonoid.Consequently, this research provides a foundation for the industrial application of S. formosum, providing critical insights into maximizing the extraction efficiency and phytochemical contents through optimized processing methods and strategic harvesting.