Fulvic acid isolation and characterisation from water of a Ramsar Lake Mansar, J&K, India

The present study was undertaken with the aim to understand the chemical properties of aquatic fulvic acid in a clear water Lake Mansar. Along with that, the physical and chemical environment of the lake was also analysed. Fulvic acid was isolated from the water of Lake Mansar following IHSS recommended methodology and was subjected to characterisation, viz. elemental analysis, H-NMR and FTIR spectroscopy. The yield of fulvic acid from water of Lake Mansar was 0.22 mg/L that was far less than coloured aquatic systems. Elemental analysis revealed per cent carbon, hydrogen, nitrogen and oxygen content to be 53.6%, 5.04%, 6.3% and 35.06%, respectively. H-NMR and FTIR spectra revealed the presence of various functional groups like aliphatic, hydroxyl, amide, quinones, ketones, carbonyl, cellulose, etc. Based on the present studies, it was concluded that the origin of humic material in Lake Mansar is mostly from algae and non-vascular plants that have undergone less degree of humification.

Identification of the Park Grass Experiment soil metaproteome

The Park Grass Experiment, is an international reference soil with an impressive repository of temperate grassland metadata, however, it still lacks documentation of its soil metaproteome. The identification of these proteins is crucial to our understanding of soil ecology and their role in major biogeochemical processes. However, protein extraction can be fraught with technical difficulties including co-extraction of humic material and lack of a compatible databases to identify proteins. To address these issues, we used two compatible soil protein extraction techniques on Park Grass soil, one that removed humic material, namely a modified freeze-dry, heat,thaw, phenol, chloroform (HTPC) method and another which co-extracted humic material, namely an established surfactant method. Proteins were identified by matching mass spectra against a tailored Park Grass metagenome database. We identified a broad range of proteins from Park Grass soil, mainly in protein metabolism , membrane transport, carbohydrate metabolism, respiration and ribosome associated categories, enabling reconstitution of specific processes active in grassland soil. The soil microbiome was dominated by Proteobacteria, Actinobacteria, Acidobacteria and Firmicutes at phyla level and Bradyrhizobium, Rhizobium, Acidobacteria, Streptomyces and Pseudolabrys at genus level. Further functional enrichment analysis enabled us to identify many proteins in regulatory and signalling networks of key biogeochemical cycles such as the nitrogen cycle. The combined extraction methods connected previous Park Grass metadata with the metaproteome, biogeochemistry and soil ecology. This could provide a base on which future targeted studies of important soil processes and their regulation can be built.

Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic Acids

A sequential chemical extraction with a defined series of eluotropic organic solvents with an increasing polarity (trichloromethane < ethyl acetate < acetone < acetonitrile < n-propanol < methanol) was performed on peat-bog humic acid. Six organic fractions were obtained and subjected to a physicochemical characterization utilizing methods of structural and compositional analysis. Advanced spectroscopic techniques such as Attenuated Total Reflectance (ATR-FTIR), total luminescence, and liquid-state 13C NMR spectrometry were combined with elemental analysis of the organic fractions. In total, the procedure extracted about 57% (wt.) of the initial material; the individual fractions amounted from 1.1% to 19.7%. As expected, the apolar solvents preferentially released lipid-like components, while polar solvents provided organic fractions rich in oxygen-containing polar groups with structural parameters closer to the original humic material. The fraction extracted with acetonitrile shows distinct structural features with its lower aromaticity and high content of protein-like structural motifs. The last two—alcohol extracted—fractions show the higher content of carbohydrate residues and their specific (V-type) fluorescence suggests the presence of plant pigment residues. The extraction procedure is suggested for further studies as a simple but effective way to decrease the structural complexity of a humic material enabling its detail and more conclusive compositional characterization.

The Effect of Composting Azolla Compost Fertilizer and Humic Material on CO2 Gas Production in Sand Land

his study was an experimental study which aimed to determine the effect of Compost Azolla Fertilizer (KA) and the addition of humic material (H) on the sand soil to the levels of CO2 produced in the respiration process of soil microorganisms (incubation soil conditions). The design used is a Completely Randomized Design (CRD) consisting of 9 treatments, namely 300 kg ha-1 urea (U), 4 tons ha-1 KA (T1), 15 liters ha-1 H (T2), 2 tons ha-1 KA + 15 liters ha-1 H (T3), 4 tons ha-1 KA + 15 liters ha-1 H (T4), 6 tons ha-1 KA + 15 liters ha-1 H (T5), 2 tons ha-1 KA + 30 liters ha-1 H (T6), 4 tons ha-1 KA + 30 liters ha-1 H (T7), 6 tons ha-1 KA + 30 liters ha-1 H (T8) and 1 control (K ) without the addition of train and H with 3 replications. Measurement of carbon dioxide (CO2) levels from each sample using gas chromatography equipped with TCD (Thermal Conductivity Detector). The statistical data analysis used was the F test, whereas to see the difference in the effect of each treatment, the BNT test was used. The results showed that Azolla compost fertilizer and humic material on sand soil had an effect on the level of CO2 gas production produced in the soil microorganisms respiration process, where the concentration of Azolla compost fertilizer and humic material which most affected the increase of CO2 gas production in sand soil was treated with the highest concentration of 6 tons ha-1 Azolla + 30 liter compost fertilizer ha-1 H (T8).

The nature of the light absorption and emission transitions of 4-hydroxybenzophenone in different solvents. A combined computational and experimental study

The photophysics and photochemistry of 4-hydroxybenzophenone (4HOBP) are interesting because they can give some insight into the behavior of humic material.