Quantitative Differences of the Components between the Inner Bark and the Outer Bark of Morus alba

Abstract

The bark of 9 Morus alba L. trees was separated into the outer bark and the inner bark by hands with the use of a pocket knife. After that, we performed a quantitative analysis of six components : contents of moisture, ashes, resins, total sugar, essential oils, and condensed tannins. The resin contents were measured using the Tappi method. The total sugar analyses were conducted using the phenol-sulfuric acid method. The essential oils were measured using the steam distilling method. Condensed tannins were tested using the vanillin-HC1 method. The outer bark contained 68% moisture, 914% ashes, 710% resins, 46% total sugars, 0.20.9% essential oils, and 1.03.5% condensed tannins, while the inner bark contained 810% moisture, 619% ashes, 410% resins, 811% total sugars, about 0.13% essential oils, and 0.30.8% condensed tannins. As a result, the analyses clearly showed that there was a significant quantitative difference between the outer bark and the inner bark for all components except ashes and resins contents based on a t-test.