Changes in Soil Humin Macromolecular Structure Resulting from Long-Term Catch Cropping.

The aim of this study was to assess the effect of long-term catch crop application on the structural properties of humin, which is considered the most recalcitrant fraction of soil organic matter. Soil samples from a 30-year field experiment on triticale cultivated with and without catch crops were analysed to determine the total organic carbon content and fractional composition of humic substances. Meanwhile, humin isolated from bulk soil was analysed to determine its elemental composition and spectroscopic properties measured with UV-Vis, fluorescence, and C-CPMAS-NMR.

Antioxidant Features of Humic Products by ABTS Assay.

Oxidative stress plays a pivotal role in driving immunosenescence by disrupting cellular homeostasis and impairing immune function. Humic substances exhibit scavenging activity against reactive oxygen species (ROS), inhibit ROS generation via metal chelation, and modulate endogenous antioxidant enzyme activity. Additionally, humic substances display anti-inflammatory effects, further supporting cellular redox balance.

Seasonal studies of aquatic humic substances from Amazon rivers: characterization and interaction with Cu (II), Fe (II), and Al (III) using EEM-PARAFAC and 2D FTIR correlation analyses.

Aquatic humic substances (AHS) are defined as an important components of organic matter, being composed as small molecules in a supramolecular structure and can interact with metallic ions, thereby altering the bioavailability of these species. To better understand this behavior, AHS were extracted and characterized from Negro River, located near Manaus city and Carú River, that is situated in Itacoatiara city, an area experiencing increasing anthropogenic actions; both were characterized as blackwater rivers. The AHS were characterized by C nuclear magnetic ressonance and thermochemolysis GC-MS to obtain structural characteristics.

Humic Substances Isolated from Recycled Biomass Trigger Jasmonic Acid Biosynthesis and Signalling.

Intensive agriculture maintains high crop yields through chemical inputs, which are well known for their adverse effects on environmental quality and human health. Innovative technologies are required to reduce the risk generated by the extensive and harmful use of pesticides. The plant biostimulants made from humic substances isolated from recyclable biomass offer an alternative approach to address the need for replacing conventional agrochemicals without compromising the crop yield.