Glyphosate Residues in Soil and Air: An Integrated Review

Glyphosate [N-(phosphonomethyl) glycine] (GPS) is currently the most commonly applied herbicide worldwide. Given the widespread use of glyphosate, the investigation of the relationship between glyphosate and soil ecosystem is critical and has great significance for its valid application and environmental safety evaluation. However, although the occurrence of glyphosate residues in surface and groundwater is rather well documented, only few information are available for soils and even fewer for air. Due to this, the importance of developing methods that are effective and fast to determine and quantify glyphosate and its major degradation product, aminomethylphosphonic acid (AMPA), is emphasized. Based on its structure, the determination of this pesticide using a simple analytical method remains a challenge, a fact known as the “glyphosate paradox.” In this chapter a critical review of the existing literature and data comparison studies regarding the occurrence and the development of analytical methods for the determination of pesticide glyphosate in soil and air is performed.

Toxicity of Canola-Derived Glucosinolate Degradation Products in Pigs—A Review

Canola co-products are widely included in swine diets as sources of proteins. However, inclusion of canola co-products in diets for pigs is limited by toxicity of glucosinolate degradation products. Aliphatic and aromatic glucosinolates are two major classes of glucosinolates. Glucosinolate degradation products derived from aliphatic glucosinolates (progoitrin) include crambene, epithionitriles, and goitrin, whereas indole-3-acetonitrile, thiocyanate, and indole-3-carbinol are the major aromatic glucosinolates (glucobrassicin)-derived degradation products. At acidic pH (<5.7), progoitrin is degraded by myrosinases to crambene and epithionitriles in the presence of iron, regardless of the presence of epithiospecifier protein (ESP), whereas progoitrin is degraded by myrosinases to goitrin in the absence of ESP, regardless of the presence of iron at neutral pH (6.5). Indole-3-acetonitrile is the major degradation product derived from glucobrassicin in the absence of ESP, regardless of the presence of iron at acidic pH (<4.0), whereas thiocyanate and indole-3-carbinol are the major glucobrassicin-derived degradation products in the absence of ESP, regardless of the presence of iron at neutral pH (7.0). In conclusion, the composition of glucosinolate degradation products is affected by parent glucosinolate composition and hindgut pH. Thus, toxicity of canola co-product-derived glucosinolates can be potentially alleviated by modifying the hindgut pH of pigs.

Deciphering the chemical instability of sphaeropsidin A under physiological conditions – degradation studies and structural elucidation of the major metabolite

The degradation of the fungal metabolite sphaeropsidin A, under physiological conditions, was investigated and the structure of the major degradation product determined.

Validated Liquid Chromatographic Method for the Determination of (Canagliflozin, Dapagliflozin or Empagliflozin) and Metformin in the Presence of (1-Cyanoguanidine)

A simple and accurate liquid chromatographic method has been developed and validated for the determination of either canagliflozin, dapagliflozin propandiol monohydrate or empagliflozin and metformin in presence of metformin major degradation product;1-cyanoguanidine. The Liquid Chromatographic (LC) method was based on isocratic elution on Prontosil (Lichrosorb 100-5-NH2) column using a mobile phase consisting of NaH2PO4 buffer (10 mM, pH 2.8):acetonitrile (18.5:81.5, v/v), at a flow rate of 2 mL/min−1. Quantitation was achieved with UV detection at 225 nm. The validation of the method was assessed according to International Conference on Harmonization (ICH) guidelines. Linearity, accuracy and precision were satisfactory over the concentration ranges of 12.5–100, 3.75–30, 0.3075–2.46, and 0.3125–2.5 μg/mL for metformin HCl, canagliflozin, dapagliflozin propandiol monohydrate and empagliflozin, respectively. Limits of detection and quantitation were found to be 0.068, 0.135, 0.077 and 0.069 μg/mL and 0.206, 0.410, 0.233 and 0.210 μg/mL for metformin HCl, canagliflozin, dapagliflozin propandiol monohydrate and empagliflozin, respectively. The developed method is suitable for the quality control and routine analysis of the cited drugs separately or in combinations.