Anti-fungal potency of essential oils with coating for surface treatment of heritage Solani Aqueduct, Roorkee, India

The Solani Aqueduct is 175 years old heritage structure in Roorkee, India. The exterior surface of structure is deteriorated due to fungal infestation. Fungi can spoil valuable heritage sites aesthetically, mechanically and chemically. Five fungi namely: Curvularia pallescens , Fusarium equiseti , Talaromyces purpureogenus , Aspergillus niger , and Alternaria alternata were isolated and identified from exterior surface of the Solani Aqueduct. Essential oils (Eucalyptus, Peppermint, and Clove) were evaluated by using agar well diffusion method against three (out of five) dominating fungi A. niger , T. purpureogenus , and A. alternata to determine the zone of inhibition. The clove oil (10000 ppm) exhibited anti-fungal activity against different fungi in the following order i.e., Alternaria > Talaromyces > Aspergillus . Further, clove oil (10000 ppm) with three individual water-repellent coatings (konex 2318, konex 2319, and zycosil-zycoprime) was applied on a white cement panel to determine their anti-fungal performance against above three fungi. The clove oil (10000 ppm) exhibited effective results against all three fungi up to 28 days. The GC-MS spectra of clove oil exhibited eugenol content of 86.95%. The maximum depth of penetration of coating was determined using various dyes and was recorded as maximum for konex 2319 (3.0 mm) followed by konex 2318 (2.7 mm) and zycosil-zycoprime (1.3 mm). On the basis of visual observation and water hydrophobicity test performed on field trial at surface of Solani Aqueduct, Roorkee, the order of effective protecting coating has been in order off clove oil (10000 ppm) with konex 2319 >konex 2318 >zycosil - zycoprime.