The water insolubleprecipitate (acetic acid lignin, AcL) had a low weight-average molecular weight range from 341 to 253 (Mw) and a narrow molecular weight distribution from 1.1 to 1.2.
Benedict 's solution is an alkaline solution of copper (ii) sulfate, which is reduced to insoluble copper (I) oxide by reducing sugars, giving a red precipitate.