Impact of Three Natural Oily Extracts as Pulp Additives on the Mechanical, Optical, and Antifungal Properties of Paper Sheets Made from and Wood Branches.

In the pulp and paper industry, several studies have been done to improve and enhance the properties of the mechanical, optical, and antimicrobial activities of pulp produced with different additives. In the present study, pulp of wood branches (WBs) from Dehnh. and (Hook.f.) Seem. was treated with -hexane oily extracts (HeOE) from L. fruits, L. leaves, and L. seeds as additives at concentrations of 1%, 3%, and 5% based on oven-dry pulp weight. Measured mechanical properties were higher in paper sheets made from than WB pulp. The highest tensile index values were observed with WB pulp treated with 5% HeOEs of (33.90 N·m/g) and (33.76 N·m/g) compared to control (32.10 N·m/g); the highest tear index with 5% HeOE of (4.11 mN·m/g) compared to control (3.32 mN·m/g); and the highest burst index with 5% HeOE of (4.11 kPa·m/g) compared to control (3.08 kPa·m/g). The highest double-fold number value (9) was observed with WB pulp treated with 5% HeOEs of , , and but with no significant difference compared to control treatment (8.33) or other HeOE treatments with WB pulp. Scanning electron microscope (SEM) examination showed clear inhibition of the growth of with WB pulp paper discs of and treated with HeOEs of , , and at 3% and 5% compared to control treatment, while HeOEs at 5% concentration showed no growth of and . The present findings establish that the HeOEs from , , and at 3% and 5% are novel natural products that can be used as alternatives to improve the properties and antifungal activity of WB pulp produced from and .