Tebuconazole

Lipopeptides used in this study were produced in shaked flasks using modified Landy media according to Coutte et al. (2010a) (link) for surfactin and fengycin production and Béchet et al. (2013) (link) for mycosubtilin production. They were purified from the fermentation broth using two steps ultrafiltration methods on 10 kDa membrane including four steps of diafiltration as previously described by Coutte et al. (2010b) (link) and Jauregi et al. (2013) (link). After freeze drying, the obtained powders of lipopeptides were then characterized using RP-HPLC and HPLC-MS as previously described (Mejri et al., 2017 (link)). In brief, surfactin are composed of isoforms with fatty acid chain of C12–C16, mycosubtilin with fatty acid chain of C15–C18 and fengycin with saturated and unsaturated fatty acid chain of C14–C18.
These three lipopeptides were tested alone (F, M, S), in binary (FS, FM, SM) and ternary mixtures (FSM) (Table 1). The antifungal activities of lipopeptides were compared to the active substance of reference: tebuconazole (Sigma-Aldrich, St. Louis, United States) which is a penetrating and systemic fungicide, from the triazoles family (DMIs).

Municipal excess-activated sewage sludge was obtained from a sewage treatment plant in Yantai City (Shandong Province, China). Diuron (>99.6%) and Chloridazon (>97%) were supplied by J&K Scientific Ltd. (St. Louis, MO, USA). Tebuconazole (>95%) and Malathion (>99.7%) were purchased from Sigma-Aldrich Corporation (Bellefonte, PA, USA). Methanol (HPLC grade) and acetonitrile (HPLC grade) were purchased from Sigma-Aldrich Corporation (Bellefonte, PA, USA). The other chemical reagents (analytical grade) were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China) and used without further purification. Considering the diversity and representativeness of the real water quality, water samples 1 to 4 were taken from Yantai City (Shandong Province) and were samples of the Guangdang River, the Fenghuangshan Reservoir, the Miaohou Reservoir, and tap water, respectively (water quality indexes of the four samples are shown in Table S3).