Bacillus species as an intrinsic controller of fungal deterioration of archival documents

• Intrinsic control of fungal deterioration of archives by Bacillus spp is proposed.
• B. licheniformis HD2, Bacillus species inhibited fungal deteriogens of paper.
• Presence of only antifungal activity by B. licheniformis HD2.
• 20 kDa antifungal protein with temperature & pH stability by B. licheniformis HD2.

The present study samples 19th century maps (belonging to India's Great Trigonometrical Survey) and daptars (official papers of Maratha history) to isolate the microflora and explore their interactions within that niche. Amongst the array of microbial isolates, the work successfully isolates a novel strain of Bacillus, producing a potent, low molecular weight, broad spectrum antagonistic protein fraction. The predominance of this species rendered the documents sampled resistant to biodeterioration in comparison to others. The antifungal activity of the isolate was attributed to a low molecular weight, heat, pH stable, extracellular protein fraction that was isolated with 30% and 60% ammonium sulfate precipitation. The activity of this fraction was established by bio-autography. Its stability upto 50 °C and resistance to proteolytic cleavage makes this protein fraction a novel broad spectrum potent antifungal candidate.