Agrochemicals, Volume 1, Issue 1 (December 2022) – 5 articles

The development of quality requirements for the analyses of chemical contaminants is reviewed from the formation of the first association of analytical chemists in 1884. Without attempting to give complete coverage, it is shown that the elaboration of quality systems is commanded by the needs of the industry and international trade. Progress along the line of the initial inter-laboratory comparison, methods validated with collaborative tests, and development of internationally harmonized guidelines and protocols to perform complex studies aiming to improve the accuracy and reliability of the results facilitate international trade, and protect consumer health, as well as the environment. The international cooperation for limiting the replication of various (e.g., analytical, toxicological) tests is promoted by multilateral agreements that are also supported by legal obligations. Notwithstanding, the rapid development of requirements and guidance documents provides only the frame for obtaining accurate, defendable results. The production of such results is the duty of the laboratory management, analysts, and study personnel who play the decisive role and bear full responsibility for the samples analyzed. Full article

Nitrogen treatment can be used as an alternative method to chemical control. Most of the research on nitrogen treatment mainly investigated the optimum concentration of oxygen level as well as duration as a means of insect control. Other parameters such as temperature and different insect species have been extensively studied and recent research focus on the modelling of nitrogen concentration and the efficacy on commodity. In this paper, we briefly review the major parameters (temperature, oxygen level, relative humidity, exposure time) using nitrogen treatment against stored product insects. Exposure to different oxygen levels or different exposure times can remarkably change pest control mortality. Moreover, different insect species and life stages have differing susceptibility to nitrogen treatment. Finally, these studies are reviewed in this paper to illustrate that nitrogen treatment can be used as a part of an IPM strategy. Full article

Ganoderma lucidum is a medicinal fungus and has been used for improvements of health or prevention of certain diseases in Asia for thousands of years. Despite numerous kinds of triterpenoids having been identified from G. lucidum, few natural Ganoderma triterpenoids exist in the form of glycosides (saponins). To expand the diversity of Ganoderma triterpenoids and find rare Ganoderma saponins, ganoderic acid F (GAF), a Ganoderma triterpenoid, was biotransformed by a glycosyltransferase (BsGT110) from Bacillus subtilis ATCC (American type culture collection) 6633. The results showed that BsGT110 catalyzed biotransformation of GAF to produce a metabolite, which was confirmed as a GAF glucoside by mass–mass spectroscopy. The GAF glucoside showed 89-fold higher aqueous solubility than that of GAF. The present study highlights the utility of BsGT110 in the production of novel Ganoderma triterpenoid saponins, and the newly identified and highly soluble GAF glucoside can be studied for its bioactivity in the future. Full article

Mitigating climate change and enhancing fertility in agricultural systems require the adoption of more sustainable fertilizer management practices. Applications of recycled organic materials, such as animal and green wastes, can promote soil carbon stabilization via changing extracellular enzyme activities while providing the necessary nitrogen (N) for plant growth. The goals of this study were to quantify the effects of compost type (cow manure, green manures, mixtures of green and cow manure at various proportions, and inorganic fertilizers) on (1) enzyme activity (phenol oxidase, peroxidase, and urease), and (2) mineralized N under laboratory incubation at 30 °C over an eight-week period. The lowest oxidative enzyme activities (phenol oxidase and peroxidase) were found in the soil treated with a mixture of 50% cow manure and 50% green manure (2.45 μmol h⁻¹ g⁻¹) and a mixture of 30% cow manure and 70% green manure (3.21 μmol h⁻¹ g⁻¹) compared to all other fertilizer treatments. The highest phenol oxidase activity was found in soils amended with green manures (3.52 μmol h⁻¹ g⁻¹), while the highest peroxidase activity was found in soils amended with a mixture of 70% cow manure and 30% green manure (5.68 μmol h⁻¹ g⁻¹). No significant differences were found in total net mineralized N content among all organic fertilizer treatments, but these were significantly lower than total net mineralized N in soil treated with inorganic fertilizers. These results indicate similar effects of organic amendments and mixtures in providing plant-available N, but different effects on lignin-degrading enzyme activities, which may lead to differences in soil organic carbon cycling and long-term C storage depending on which organic amendment is utilized. Full article