ABSTRACT
Garlic oil has a wide range of biological activities, and its broad-spectrum activity against phytopathogenic fungi still has the potential to be explored. In this study, enzymatic treatment of garlic resulted in an increase of approximately 50 % in the yield of essential oil, a feasible GC-MS analytical program for garlic oil was provided. Vacuum fractionation of the volatile oil and determination of its inhibitory activity against 10 fungi demonstrated that garlic oil has good antifungal activity. The antifungal activity levels were ranked as diallyl trisulfide (S-3)>diallyl disulfide (S-2)>diallyl monosulfide (S-1), with an EC50 value of S-3 against Botrytis cinerea reached 8.16â mg/L. Following the structural modification of compound S-3, a series of derivatives, including compounds S-4~7, were synthesized and screened for their antifungal activity. The findings unequivocally demonstrated that the compound dimethyl trisulfide (S-4) exhibited exceptional antifungal activity. The EC50 of S-4 against Sclerotinia sclerotiorum reached 6.83â mg/L. SEM, In vivo experiments, and changes in mycelial nucleic acids, soluble proteins and soluble sugar leakage further confirmed its antifungal activity. The study indicated that the trisulfide bond structure was the key to good antifungal activity, which can be developed into a new type of green plant-derived fungicide for plant protection.
Subject(s)
Allyl Compounds , Antifungal Agents , Garlic , Microbial Sensitivity Tests , Oils, Volatile , Sulfides , Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Oils, Volatile/isolation & purification , Oils, Volatile/chemical synthesis , Sulfides/pharmacology , Sulfides/chemistry , Garlic/chemistry , Antifungal Agents/pharmacology , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Allyl Compounds/pharmacology , Allyl Compounds/chemistry , Allyl Compounds/isolation & purification , Allyl Compounds/chemical synthesis , Distillation , Drug Design , Botrytis/drug effects , Structure-Activity Relationship , Ascomycota/drug effects , Molecular StructureABSTRACT
Bacterial resistance to commonly used antibiotics has been recognized as a significant global health issue. In this study, we carried out the screening of a family of allylic thiocyanates for their action against a diversity of bacteria and fungi with a view to developing new antimicrobial agents. Allylic thiocyanates bearing halogenated aryl groups, which were readily obtained in two steps from the Morita-Baylis-Hillman adducts, showed moderate-to-high activity against selective pathogens, including a methicillin-resistant S. aureus (MRSA) strain. In particular cases, methyl (Z)-3-(2,4-dichlorophenyl)-2-(thiocyanomethyl)-2-propenoate exhibited antimicrobial activity comparable to the reference antibiotic Imipenem.
Subject(s)
Allyl Compounds/pharmacology , Anti-Infective Agents/pharmacology , Bacteria/drug effects , Fungi/drug effects , Thiocyanates/pharmacology , Allyl Compounds/chemical synthesis , Microbial Sensitivity Tests , Thiocyanates/chemical synthesisABSTRACT
Allyl 1-naphthyl ethers are useful compounds for different purposes, but reported methods to synthesize them require long reaction times. In this work, we have obtained allyl 1-naphthyl ether in good yield using ultrasonic-assisted methodology in a 1-h reaction. A central composite design was used to obtain a statistical model and a response surface (p < 0.05; R2 = 0.970; R2adj = 0.949; R2 pred = 0.818) that can predict the optimal conditions to maximize the yield, validated experimentally.