Suberin Fatty Acids from Outer Birch Bark: Isolation and Physical Material Characterization

Abstract

The isolation and physical material properties of suberin fatty acids (SFAs) were investigated with special reference to their potential applications as novel pharmaceutical excipients. SFAs were isolated from outer birch bark (OBB) with a new extractive hydrolysis method. The present simplified isolation process resulted in a moderate batch yield and chemical purity of SFAs, but further development is needed for establishing batch-to-batch variation. Cryogenic milling was the method of choice for the particle size reduction of SFAs powder. The cryogenically milled SFAs powder exhibited a semicrystalline structure with apparent microcrystalline domains within an amorphous fatty acids matrix. The thermogravimetric analysis (TGA) of SFAs samples showed a good thermal stability up to 200 °C, followed by a progressive weight loss, reaching a plateau at about 95% volatilization at about 470 °C. The binary blends of SFAs and microcrystalline cellulose (MCC; Avicel PH 101) in a ratio of 25:75 (w/w) displayed good powder flow and tablet compression properties. The corresponding theophylline-containing tablets showed sustained or prolonged-release characteristics. The physicochemical and bulk powder properties of SFAs isolated from OBB are auspicious in terms of potential pharmaceutical excipient applications.

Improving dimensional stability of Populus cathayana wood by suberin monomers with heat treatment

“…Kitin et al (2020) also reported the fluorescence of lignin and suberin in plant cells under CLSM. Heinämäki et al (2017) confirmed the melting behavior of suberin monomers. Therefore, the fluorescence of cell wall was brighter and SMs have a uniform distribution after heat treatment.…”

Antimicrobial activity and chemical composition of white birch (Betula papyrifera Marshall) bark extracts

“…The high proportions of lignin, cellulose, and hemicellulose ( Figure 2) suggest a high calorific value of the material as well as low ash content. In addition, in the case of birch bark, the extractive compounds ( Figure 2) may include suberin and betulin, which are the main components giving 1.5 times higher heating value in comparison with wood components (Ferreira et al, 2013;Heinamaki et al, 2017). Several studies have shown that there was a highly significant linear correlation between the higher heating value of the extractive-free wood and lignin content (Demirbaş, 2001;White, 1987) and another one showed that high ash content in parts of a plant makes it less desirable as fuel (Demirbas, 2002).…”

The Hydrophobicity of Lignocellulosic Fiber Network Can Be Enhanced with Suberin Fatty Acids

“…Birch outer bark is rich in valuable biochemicals like the naturally occurring biopolyester suberin and the triterpenoids betulinol and lupeol [12,13,14,15,16]. The content of betulinol and lupeol in outer bark varies between 30%–35% and the content of suberin can be up to 40%–50% [13,17].…”