Carbamate pesticides, a new type of broad-spectrum pesticides for controlling pests, mites, and weeds, are developed to address the shortcomings of organochlorine and organophosphorus pesticides. Their widespread use and slow degradation have led to environmental pollution, causing damage to ecosystems and human health. Managing pesticide residues is a pressing issue in the current environmental protection. This study aims to investigate the expression of SyEst870, a member of the SGNH/GDSL hydrolase family in Sphingobium yanoikuyae, in a prokaryotic system and evaluate the ability of the recombinant protein to degrade carbamate pesticides. The prokaryotic expression vector pET-32a-SyEst870 was constructed and transformed into the Escherichia coli BL21 for heterologous expression. The purified protein was studied in terms of enzyme activity and effects of temperature, pH, and metal ions on the enzyme activity, with p-nitrophenol acetate as the substrate and based on the standard curve of p-nitrophenol. LC-MS (liquid chromatography-mass spectrometry) was employed to examine the degradation effects of SyEst870 on carbaryl, metolcarb, and isoprocarb. GC-MS (gas chromatography-mass spectrometry) was employed to detect the degradation products of SyEst870 for the three pesticides. The soluble protein SyEst870 was successfully obtained through the heterologous expression in Escherichia coli, which yielded an enzyme with the activity of 677.5 U after affinity chromatography. SyEst870 exhibited degradation rates of 82.34%, 84.43%, and 92.87% for carbaryl, metolcarb, and isoprocarb, respectively, at an initial concentration of 100 mg/L within 24 h at 30 ℃ and pH 7.0. The primary degradation products of carbaryl were identified as α-naphthol and methyl isocyanate. Metolcarb was mainly degraded into m-cresol and methyl isocyanate, and isoprocarb was mainly degraded into 2-isopropylphenol and methyl isocyanate. Compared with the half-life of carbamate pesticides in the natural environment, which ranges from a few days to several weeks, the recombinant protein SyEst870 can rapidly eliminate the residues of carbamate pesticides. This study lays a foundation for addressing pesticide residues in the environment and in fruits and vegetables.
Escherichia coli/metabolism* ; Sphingomonadaceae/genetics* ; Recombinant Proteins/metabolism* ; Biodegradation, Environmental ; Esterases/metabolism* ; Pesticides/isolation & purification* ; Carbamates/isolation & purification*

AIM: To study the chemical constituents of Siegesbeckia pubescens. METHODS: The chemical constituents were isolated by extraction, crystallization and various chromatographic methods, and the chemical structures were elucidated on the basis of spectral analysis. In addition, the cytotoxic activity of compound 1 was evaluated using human lung cancer cell A 549. RESULTS: Four compounds were obtained, and their structures were identified as (E)-3-(3-oxobut-1-enyl)phenyl dimethylcarbamate (1), ent-2-oxo-15, 16, 19-trihydroxypimar-8(14)-ene (2), 16-acetylkirenol (3), 3, 7-dimethylquercetin (4). CONCLUSION Compound 1 is a new carbamate, and the IC(50) in MTT method of compound 1 was 58 μg·mL(-1).
Antineoplastic Agents, Phytogenic ; isolation & purification ; pharmacology ; therapeutic use ; Asteraceae ; chemistry ; Carbamates ; isolation & purification ; pharmacology ; therapeutic use ; Cell Line, Tumor ; Humans ; Inhibitory Concentration 50 ; Lung Neoplasms ; drug therapy ; Molecular Structure ; Phytotherapy ; Plant Components, Aerial ; chemistry ; Plant Extracts ; chemistry ; pharmacology ; therapeutic use ; Quercetin ; analogs & derivatives ; isolation & purification

OBJECTIVEDetect the pathogenicity of fungi isolated from American ginseng seeds and select new fungicides against the pathogenic seed-born fungi.

METHODinoculate the isolates to American ginseng seedlings to detect the pathogenicity, and seeded the hyphae disk at the center of agar plate containing chemicals to do fungicide bioassay.

RESULTFusarium sp. isolate 5 and Alternara sp. isolate 13 had pathogenicity to American ginseng seedling. Sportak had the strongest inhibition to the two isolates, Carbendazim had better inhibition and Celest had weak inhibition.

CONCLUSIONSportak and Celest could be used as efficacious candidate chemicals to treat or coat the American ginseng seeds, and substitute Carbendazim, which has been used for many years, to control the diseases occurring in seedling stage of American ginseng.

Alternaria ; drug effects ; isolation & purification ; Benzimidazoles ; pharmacology ; Carbamates ; pharmacology ; Fungicides, Industrial ; pharmacology ; Fusarium ; drug effects ; isolation & purification ; Panax ; growth & development ; microbiology ; Plants, Medicinal ; growth & development ; microbiology ; Seedlings ; growth & development ; microbiology ; Seeds ; growth & development ; microbiology