Question

Percentage of lignin in sugarcane bagasse (Saccharum officinarum)

• A. 4-6
• B. 15-19
• C. 25-32
• D. 40-45

Hint:

Lignocellulosic biomass composition of Bagasse:
- Cellulose: High (\(\approx 40-45\%\))
- Hemicellulose: Medium (\(\approx 25-30\%\))
- Lignin: Low-Medium (\(\approx 15-19\%\))

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Sugarcane bagasse is the fibrous residue that remains after crushing sugarcane stalks to extract their juice.
It is a lignocellulosic biomass material composed of three primary organic polymers: cellulose, hemicellulose, and lignin.
Detailed Explanation:
The chemical composition of dry sugarcane bagasse typically includes:
- Cellulose (\(40-45\%\)): The primary structural polymer that provides mechanical strength.
- Hemicellulose (\(25-30\%\)): A branched polysaccharide matrix that binds cellulose fibers together.
- Lignin (\(15-20\%\)): A complex, cross-linked phenolic polymer. Lignin fills the spaces in the cell wall between cellulose and hemicellulose, acting as a natural, hydrophobic binder that protects the plant from microbial decay and physical damage.
- Analyzing the options:
- The range \(15-19\%\) (Option B) accurately represents the typical lignin content of dry sugarcane bagasse.
- Low values like \(4-6\%\) are typical of simple annual grass leaves, while high values like \(25-32\%\) or \(40-45\%\) are typical of hard woody trees.

Step 2: Final Answer:
The percentage of lignin in sugarcane bagasse is 15-19%.