α‐Amylase Inhibitors from Wheat Against Development and Toxigenic Potential ofFusarium verticillioides

Abstract

Fusarium verticillioides is one of the most important pathogens in maize and is a producer of fumonisin B1 (FB1). Although reports of its presence in wheat are scarce, the susceptibility of this cereal to fungus of the same genus motivates interest in investigating compounds present in the grain with inhibitory activity against this species. The aim of this study was to extract α‐amylase inhibitors from wheat and apply them in vitro to evaluate its effect on the development and expression of toxigenic potential of F. verticillioides. The α‐amylase inhibitors, both crude (P0) and purified (P1), were applied to in vitro culture containing a pathogen mycelium disc. Mycelial growth of the pathogen, glucosamine content, α‐amylase activity, and production of FB1 were investigated. All protein extracts of wheat showed the ability to inhibit pathogen growth, especially the extract P0 from cultivar Quartzo, which resulted in a reduction of glucosamine content (66%) and α‐amylase activity (84%). Furthermore, the protein inhibitors showed antifumonisin effect, reducing by 33 and 47% the mycotoxin production when applied as P0 and P1, respectively. These results suggest that α‐amylase inhibitor contributed to resistance against pathogen attack, acting in a diversified manner for each fungal species.

Inhibition of Enzymatic and Oxidative Process by Phenolic Extracts from Spirulina sp. and Nannochloropsis sp.

“…1, evaporated in a rotary evaporator (801-802; Fisatom, São Paulo, Brazil) at 50 °C, diluted in 40 mL sterile distilled water and clarified with 10 mL Ba(OH) 2 (p.a., Labsynth®) 0.1 M and 10 mL ZnSO 4 (p.a., Labsynth®) 5%. Clarified extracts were vacuum filtered (MA 454; Marconi, São Paulo, SP) with sterile membrane (pore size 0.25 μm; Minisart, Goettingen, Germany) ( 3 ). …”

“…These compounds in the cell or as extracts may also be of benefit for the human diet by providing it with polyunsaturated fatty acids, peptides, chlorophyll, carotenoids, vitamins and phenolic compounds ( 2 , 3 ). …”

“…A broad discussion about the applicability of bioactive phenolic compounds is currently underway, with many authors proposing their utilization as dietary supplements against oxidative stress promoted by biotic and abiotic effects ( 3 - 5 ). This utilization finds its rationale in the fact that cells with phenolic compounds in their constitution are more resistant to oxidative damage and fungal contamination, since some phenolic compounds act as hydrolase and oxide reductase inhibitors ( 3 , 6 ).…”

“…This utilization finds its rationale in the fact that cells with phenolic compounds in their constitution are more resistant to oxidative damage and fungal contamination, since some phenolic compounds act as hydrolase and oxide reductase inhibitors ( 3 , 6 ). Some phenolic acids have defined biological activities, such as anti-inflammatory and antimicrobial activity (gallic acid) and antifungal effect (caffeic acid) ( 7 ).…”

Dual RNA-sequencing of Fusarium head blight resistance in winter wheat

“…These α-amylase inhibitors have been shown to accumulate at significantly higher levels in wheat kernels of FHB-resistant cultivars relative to FHB-susceptible lines ( Perlikowski et al., 2014 ). α-amylases are necessary for starch hydrolysis in Fusarium graminearum , where reducing α-amylase activity can lead to reduced trichothecene production and ultimately reduced pathogenicity in wheat ( Oh et al., 2016 ) Further, these α-amylase inhibitors have been shown to inhibit pathogen growth in vitro and reduce mycotoxin production by the pathogen ( Mendes et al., 2015 ).…”