Production and Application of Xylanase from Penicillium sp. Utilizing Coffee By-products

The lignocellulosic coffee by-products such as
coffee pulp, coffee cherry husk, silver skin, and spent
coffee were evaluated for their efficacy as a sole carbon
sources for the production of xylanase in solid-state
fermentation using Penicillium sp. CFR 303. Among the
residues, coffee cherry husk was observed to produce
maximum xylanase activity of 9,475 U/g. The process
parameters such as moisture (50%), pH (5.0), temperature
(30°C), particle size (1.5 mm), inoculum size (20%),
fermentation time (5 days), carbon source (xylose), and
nitrogen source (peptone) were optimized and the enzyme
activity was in the range of 19,560–20,388 U/g. The
enzyme production was further improved to 23,494 U/g
with steam as a pre-treatment. The extracellular xylanase
from the fungal source was purified to homogeneity from
culture supernatant by ammonium sulfate fractionation,
DE32-cellulose with a recovery yield of 25.5%. It appeared
as a single band on SDS-PAGE gel with a molecular mass
of approximately 27 kDa. It had optimum parameters of
50°C temperature, pH5.0, Km 5.6 mg/mL, and Vmax
925 μmol mg−1min−1 with brichwood xylan as a substrate.
The crude enzyme hydrolysed lignocellulosic substrate as
well as industrial pulp. Production of xylanase utilizing
coffee by-products constitutes a renewable resource and is
reported for the first time.