Mycosynthesis of Silver Nanoparticles Using Screened <i>Trichoderma</i> Isolates and Their Antifungal Activity against <i>Sclerotinia sclerotiorum</i>

• Main Authors: Ali Athafah Tomah, Iman Sabah Abd Alamer, Bin Li, Jing-Ze Zhang
• Format: Article
• Language: English
• Published: MDPI AG 2020-09-01
• Series: Nanomaterials
• Subjects: <i>Trichoderma virens</i>; gliotoxin; molecular interaction; antifungal activity; Sclerotia
• Online Access: https://www.mdpi.com/2079-4991/10/10/1955

To control the disease caused by <i>Sclerotinia sclerotiorum</i>, a total of 15 isolates of the <i>Trichoderma</i> species was screened for the biosynthesis of silver nanoparticles (AgNPs). Among them, the highest yield occurred in the synthesis of AgNPs using a cell-free aqueous filtrate of <i>T.virens</i> HZA14 producing gliotoxin. The synthetic AgNPs were charactered by SEM, EDS, TEM, XRD, and FTIR. Electron microscopy studies revealed that the size of AgNPs ranged from 5–50 nm and had spherical and oval shapes with smooth surfaces. Prepared AgNPs interacted with protein, carbohydrate and heterocyclic compound molecules, and especially, interaction patterns of AgNPs with the gliotoxin molecule were proposed. The antifungal activity assays demonstrated that percentage inhibition of the prepared AgNPs was 100, 93.8 and 100% against hyphal growth, sclerotial formation, and myceliogenic germination of sclerotia at a concentration of 200 μg/mL, respectively. The direct interaction between nanoparticles and fungal cells, including AgNPs’ contact, accumulation, lamellar fragment production and micropore or fissure formation on fungal cell walls, was revealed by SEM and EDS. These will extend our understanding of the mechanisms of AgNPs’ action for preventing diversified fungal disease.