Extraction of bioactive phytochemicals on Berlin banana flower ( <i>Musa acuminate</i> AA.) using continuous system-designed ultrasound machine

Berlin banana flower (Musa acuminate AA.) was widely found in Indonesia, it is believed to contain rich bioactive phytochemical constituents. A novel prototype, a continuous system-designed ultrasound machine (CDUM), was utilized to extract the constituents of the Berlin banana flower. Extraction was done for three parts of the Berlin banana flower (inner bud, outer bud, and male flower), for each 15 min, working the solvent in different polarities (distilled water, ethanol 100%, and ethanol 50%). CDUM was equipped with a novel element namely a double-jacket chiller to hold stable temperature (≤ 30 °C) for running time. Results, the highest extract yields of all extracted Berlin banana flower parts (13.80 ± 0.16% - 15.33 ± 0.18%) was generated by the ethanol 50%. However, the extract yield average of each part was equal. By the best solvent, the male flower part extract had the highest antioxidant capacity (47.13 ± 0.72%). Bioactive phytochemical classes i.e. phenolics, terpenoids, alkaloids, amino acid derivatives, fatty acid derivatives, organic sulfur-containing compounds, and saponins were contained in the extracts of different Berlin banana flower parts. The richest phenolics (12 compounds) were present in the male flower part extract., mainly gallic acid, caffeic acid, phenyllactic acid, 2,3-Dihydro-1-benzofuran-2-carboxylic acid, 4-(hydroxymethyl)benzoic acid, and 2,5-di-tert-Butylhydroquinone, which are only contained in it. The CDUM extracted the Berlin banana flower more efficiently (high yield, low energy consumption) than the conventional technique.