The effect of orange, pineapple, and guava waste extract on the phenolic content in green betel (Piper betle L.)

Indonesia as a country with a high diversity of fruit species leads to a lot of rotten fruit waste. Guava, orange, and pineapple are the example of the fruits with high abundance as rotten fruit waste. The fruits have a high content of bioactive molecules such as salicylic acid (SA). SA can cause the plant physiological defence that plays a role in increasing plant phenolic content. Phenolic compounds which have an important role as medicines known synthesized in Piper betle as one of the defence compounds. This research aimed to know the effect of orange, pineapple, and guava fruits waste on phenolic compound content in P. betle. The SA treatment was used to evaluate the optimal increasing of phenolic content of P. betle, a series of treatment of fruits waste ethanol extract were performed to P. betle plants, histochemical analysis on stem and leaf of P. betle, the total phenolic analysis using Folin-Ciocalteau method and quantitative analysis using Thin Layer Chromatography method. Based on this study, the optimum concentration of SA which could increasing the content of the phenolic compound in P. betle was 1.5 mM. Based on the histochemical and total phenolic analysis, orange was the best fruit which could increasing the content of the phenolic compound was in 50 concentration. The result of TLC analysis showed that the higher phenolic compound was resulted from orange treatment in 75 and 50 concentration. All of the analysis showed that the best treatment for increasing phenolic compound in P. betle was the orange waste extract.