Xylanase

XYLANASE

It is a hydrolase that catalyses the hydrolysis of complex sugars (primarily xylan and certain related compounds) to simpler sugars (the primary product being xylose).

  • Systematic Name: 1,4-β-D-xylanohydrolase

  • Recommended Name: endo-1,4-β-xylanase

  • Type: Hydrolase

  • Substrate: Xylan

  • Product: Xylose

  • Sources:

      • Bacterial: Bacillus polymyxa, Cryptococcus albidus etc.

      • Fungal: Aspergillus spp. (nidulans, ochraceus, fumigatus), Trichoderma spp. etc.

PROPERTIES:

  • pH Range: Acidic (3.5 – 7.0)

  • Optimum pH: 5.3

  • Temperature Range: 35 – 60 °C

  • Optimum Temperature: 55 °C

APPLICATIONS OF XYLANASE:

  a) Kraft Pulp Bleaching:
Xylanase is used in paper industry to improve the strength of cellulose fibers in bleached Kraft Pulp (from bamboo, eucalyptus etc.).
It improves pulp fibrillation and water retention, reduces beating times in virgin pulps, restores bonding, increases freeness in recycled fibers and selectively removes xylan from dissolving pulps.

  b) De-inking of Newsprint:
Cellulase blended with xylanase in specific ratios is used for deinking newsprint. At optimum ratio (50-50), brightness of deinked pulp is higher, ink removal ratio is lower and breaking length, bursting index and tearing index are higher than for chemically deinked pulp. This process also gives a higher yield than chemical deinking.

  c) In Poultry Industry:
Xylanase is added to poultry feed material such as rice/wheat bran along with various other enzymes to improve absorption of nutrients by the birds and to reduce the quantity and nutrient concentration of the birds’ droppings.

    d) In Wine Production:
It is used to break down xylans, pectin and hemicellulose present in fruits into simpler molecules such as xylose and glucose. By breaking down cell walls, it helps extract more juice from the fruit.

  e) In Baking:
Xylanase breaks down glycosidic linkages in...