Physicochemical Characteristics Research Articles

Identification, Molecular Characterization and Preliminary Functional Analysis of Three SLC27A Full-CDS cDNAs from Water Buffalo (Bubalus bubalis)

Background: Solute carrier family 27 family (SLC27As) have been identified to be involved in long chain fatty acid uptake in various tissues and cells, but their function in buffalo is unclear. Buffalo is an important dairy animal in some parts of the world. Buffalo milk contains more fat, protein, lactose and minerals than cow’s milk. The objective of this study was to identify the buffalo SLC27A1, 2 and 6 genes and to describe their characteristics, structure and basic function. Methods: The full-length coding sequences (CDSs) of SLC27A1, 2 and 6 were isolated from Binglangjiang buffalo and bioinformatics analyses were used to provide insights into the physicochemical characteristics, structure and function of their encoded proteins. Result: The CDSs of buffalo SLC27A1, 2 and 6 were 1941 bp, 1863 bp and 1905 bp in length, respectively, encoding 646, 620 and 634 amino acid residues accordingly. Their proteins FATP1, 2 and 6 have no signal peptide but a transmembrane helix with the N-terminus located outside the membrane and the C-terminus located in cytoplasmic side. All three proteins contain AMP-binding domains that belonged to AFD_class_I superfamily and may play a crucial role in the transport of fatty acids. The amino acid sequences of buffalo FATP1, 2 and 6 showed more than 88.6% identity with other species of Bovidae and more than 76.4% identity with other species of mammals. The phylogenetic tree showed that buffalo FATP1, 2 and 6 clustered in their respective clades and buffalo was more closely genetically related to other species of the Bovidae family. These findings suggest that buffalo FATPs are more similar in function to other species. The present study will provide a theoretical basis for further investigation of the functions of FATP1, 2 and 6 in buffalo lipid metabolism, especially milk fat metabolism.

Effect of apple peel flour addition on physicochemical characteristics and fatty acid profile of reduced-fat mayonnaise

Introduction: Mayonnaise is popular throughout the world and contains various types of processed products. While reduced-fat mayonnaise (RFM) contains less than 50% oil, the drawback is the potential to reduce the physical quality of mayonnaise. The use of apple peel in the form of flour added to mayonnaise is predicted to enhance its physicochemical quality. Methods: The research comprised laboratory experiments using randomised design with four treatments and six repetitions. Apple peel flour was added to the treatments in the following proportions: 0% (RFA0), 1% (RFA1), 2% (RFA2), and 3% (RFA3). Analysis of variance (ANOVA) was used to obtain average values and standard deviations. Results: Addition of 3% apple peel flour to RFM showed highly significant effect (p≤0.01) on droplet size (2.15–9.49µm), viscosity (3965.00cP), colours L (71.93), a* (15.75), and b* (50.65), protein content (1.44%), and fat content (50.93%). It also produced an organoleptic quality that was acceptable to semi-trained panellists and fatty acid profiles containing various types of fatty acids. Conclusion: The use of 3% apple peel flour in RFM represented the best treatment, with potential for further improvement.

Physicochemical Characterization and Antioxidant Activity of Jara Honey Produced in Western Georgia

The purpose of this research article was to study the physicochemical characteristics of semi-wild Jara honey grown in Western Georgia. Jara honey is produced in the alpine and sub-alpine forest zone of high mountain Adjara, which is distinguished by its variety of honey plants. The physicochemical characteristics were examined concerning the Alimemtarius Code and EU regulations: moisture content, total carbohydrates, free acidity, pH, electrical conductivity, microelements (Li, Na, K, Mg, Ca), color, total phenols, total phenolic acids, total flavonoids, proline, diastase activity, proteins, and microscopic study of pollens. Using the UPLC-MSB method, grayanotoxin-III was identified in the semi-wild Jara honey samples. The findings demonstrated that the honey has significant concentrations of phenols, phenolic acids, and flavonoids. A directly proportional relationship was established between the quantitative content of phenolic compounds and the antioxidant activity of honey. This article is the first study of the characteristics of Jara honey produced in Western Georgia.

Green synthesis of magnetite iron oxide nanoparticles using Azadirachta indica leaf extract loaded on reduced graphene oxide and degradation of methylene blue

In the current arena, new-generation functional nanomaterials are the key players for smart solutions and applications including environmental decontamination of pollutants. Among the plethora of new-generation nanomaterials, graphene-based nanomaterials and nanocomposites are in the driving seat surpassing their counterparts due to their unique physicochemical characteristics and superior surface chemistry. The purpose of the present research was to synthesize and characterize magnetite iron oxide/reduced graphene oxide nanocomposites (FeNPs/rGO) via a green approach and test its application in the degradation of methylene blue. The modified Hummer's protocol was adopted to synthesize graphene oxide (GO) through a chemical exfoliation approach using a graphitic route. Leaf extract of Azadirachta indica was used as a green reducing agent to reduce GO into reduced graphene oxide (rGO). Then, using the green deposition approach and Azadirachta indica leaf extract, a nanocomposite comprising magnetite iron oxides and reduced graphene oxide i.e., FeNPs/rGO was synthesized. During the synthesis of functionalized FeNPs/rGO, Azadirachta indica leaf extract acted as a reducing, capping, and stabilizing agent. The final synthesized materials were characterized and analyzed using an array of techniques such as scanning electron microscopy (SEM)-energy dispersive X-ray microanalysis (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis, and UV–visible spectrophotometry. The UV–visible spectrum was used to evaluate the optical characteristics and band gap. Using the FT-IR spectrum, functional groupings were identified in the synthesized graphene-based nanomaterials and nanocomposites. The morphology and elemental analysis of nanomaterials and nanocomposites synthesized via the green deposition process were investigated using SEM–EDX. The GO, rGO, FeNPs, and FeNPs/rGO showed maximum absorption at 232, 265, 395, and 405 nm, respectively. FTIR spectrum showed different functional groups (OH, COOH, C=O), C–O–C) modifying material surfaces. Based on Debye Sherrer's equation, the mean calculated particle size of all synthesized materials was < 100 nm (GO = 60–80, rGO = 90–95, FeNPs = 70–90, Fe/GO = 40–60, and Fe/rGO = 80–85 nm). Graphene-based nanomaterials displayed rough surfaces with clustered and spherical shapes and EDX analysis confirmed the presence of both iron and oxygen in all the nanocomposites. The final nanocomposites produced via the synthetic process degraded approximately 74% of methylene blue. Based on the results, it is plausible to conclude that synthesized FeNPs/rGO nanocomposites can also be used as a potential photocatalyst degrader for other different dye pollutants due to their lower band gap.

Synthesis of Zn2+:LaMnO3 perovskites nanoparticles by facile co-precipitation approach: Physicochemical characteristics and supercapacitor application

This work has examined the impact of Zn2+ on the crystal architecture and electrochemical functionality of LaMnO3 perovskite nanoparticles. Crystalline parameters of the as-prepared samples were analyzed by X-ray Diffraction studies (XRD). Fourier transform infrared (FT-IR) measurements are utilized to detect the functional groups present in the sample. Raman spectroscopy technique was used to analyze the nature of the chemical bonds in the prepared material. The shape and elemental content of the produced nanomaterials were determined using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDAX). Brunauer-Emmett-Teller (BET) technique is used to study the porosity and surface area of the material. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge/discharge (GCD) is employed to study the surface resistivity, oxidation–reduction potential and super capacitance efficiency of the prepared electrode material.

Morphological, Physiological, and Photosynthetic Differences of Tartary Buckwheat Induced by Post-Anthesis Drought

Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn) is a crop of significant interest due to its nutritional value and resilience to drought conditions. However, drought, particularly following flowering, is a major factor contributing to yield reduction. This research employed two distinct Tartary buckwheat genotypes to investigate the effects of post-anthesis drought on growth and physicochemical characteristics. The study aimed to elucidate the response of Tartary buckwheat to drought stress. The findings indicated that post-anthesis drought adversely impacted the growth, morphology, and biomass accumulation of Tartary buckwheat. Drought stress enhanced the maximum photosynthetic capacity (Fv/Fm) and light protection ability (NPQ) of the ‘Xiqiao-2’ genotype. In response to drought stress, ‘Dingku-1’ and ‘Xiqiao-2’ maintained osmotic balance by accumulating soluble sugars and proline, respectively. Notably, ‘Xiqiao-2’ exhibited elevated levels of flavonoids and polyphenols in its leaves, which helped mitigate oxidative damage caused by drought. Furthermore, rewatering after a brief drought period significantly improved plant height, stem diameter, and biomass accumulation in ‘Dingku-1’. Overall, ‘Xiqiao-2’ demonstrated greater long-term tolerance to post-anthesis drought, while ‘Dingku-1’ was less adversely affected by short-term post-anthesis drought.

Organic solvent-free benznidazole nanosuspension as an approach to a novel pediatric formulation for Chagas disease.

Aim: Benznidazole (BNZ), a class-II drug, is the primary treatment for Chagas disease, but its low aqueous solubility presents challenges in formulation and efficacy. Nanosuspensions (NS) could potentially address these issues. Methods: BNZ-NS were prepared using a simple, organic solvents-free nano-milling approach. Physicochemical characterizations were conducted on both NS and lyophilized solid-state BNZ-nanocrystals (NC). Results: BNZ-NS exhibited particle size <500nm, an acceptable polydispersity index (0.23), high Z-potential, and physical stability for at least 90days. BNZ-NC showed tenfold higher solubility than pure BNZ. Dissolution assays revealed rapid BNZ-NS dissolution. BNZ-NC demonstrated biocompatibility on an eukaryotic cell and enhanced BNZ efficacy against trypomastigotes of Trypanosoma cruzi. Conclusion: BNZ-NS offers a promising alternative, overcoming limitations associated with BNZ for optimized pharmacotherapy.

Assessment of water quality in wells and springs across various districts of Taza City, Morocco

ABSTRACT The aim of this study is to assess groundwater pollution in the city of Taza, Morocco. This was accomplished through hydrochemical and biological investigations, focusing on analyzing the physicochemical and bacteriological parameters of groundwater. Water samples were collected from wells and sources within Taza City on a monthly basis during the spring and summer of 2023. These samples were subjected to analysis to identify physicochemical and bacteriological characteristics. The findings revealed multiple contaminations, primarily stemming from two sources: significant microbial pollution observed in 100% of samples due to runoff percolation and discharge of domestic and industrial wastewater, and varying degrees of chemical pollution observed across all samples. The results underscored deviations from national standards, notably in parameters such as dissolved oxygen, nitrate, and nitrite concentrations. These parameters exhibited values either lower or higher than the established norm.

Metal–Organic Framework-Derived Rare Earth Metal (Ce-N-C)-Based Catalyst for Oxygen Reduction Reactions in Dual-Chamber Microbial Fuel Cells

Pt supported on carbon (Pt/C) is deemed as the state-of-the-art catalyst towards oxygen reduction reactions (ORRs) in chemical and biological fuel cells. However, due to the high cost and scarcity of Pt, researchers have focused on the development of Earth-abundant non-precious metal catalysts, hoping to replace the traditional Pt/C catalyst and successfully commercialize the chemical and biological fuel cells. In this regard, electrocatalysts made of transition metals emerged as excellent candidates for ORRs, especially the electrocatalysts made of Fe and Co in combination with N-doped carbons, which produce potentially active M-N4-C (M=Co, Fe) ORR sites. At present, however, the transition metal-based catalysts are popular; recently, electrocatalysts made of rare earth metals are emerging as efficient catalysts, due to the fact that rare earth metals also have the potential to form rare earth metal-N4-C active sites, just like transition metal Fe-N4-C/Co-N4-C. In addition, mixed valance states and uniqueness of f-orbitals of the rare earth metals are believed to improve the redox properties of the catalyst that helps in enhancing ORR activity. Among the rare earth metals, Ce is the most interesting element that can be explored as an ORR electrocatalyst in combination with the N-doped carbon. Unique f-orbitals of Ce can induce distinctive electronic behavior to the catalyst that helps to form stable coordination structures with N-doped carbons, in addition to its excellent ability to scavenge the OH● produced during ORRs, therefore helping in catalyst stability. In this study, we have synthesized Ce/N-C catalysts by a metal–organic framework and pyrolysis strategy. The ORR activity of Ce/N-C catalysts has been optimized by systematically increasing the Ce content and performing RDE studies in 0.1 M HClO4 electrolyte. The Ce/N-C catalyst has been characterized systematically by both physicochemical and electrochemical characterizations. The optimized Ce/N-C-3 catalyst exhibited a half-wave potential of 0.68 V vs. RHE. In addition, the Ce/N-C-3 catalyst also delivered acceptable stability with a loss of 70 mV in its half-wave potential when compared to 110 mV loss for Pt/C (10 wt.%) catalyst, after 5000 potential cycles. When Ce/N-C-3 is used as a cathode catalyst in dual-chamber microbial fuel cells, it delivered a volumetric power density of ⁓ 300 mW m−3, along with an organic matter degradation of 74% after continuous operation of DCMFCs for 30 days.

Physicochemical characteristics of highly concentrated suspensions with some types of Ukrainian coal

ABSTRACT The investigation results of granulometric composition, zeta potential, sedimentation stability, and viscosity of some water-coal suspensions made of Ukrainian coal from the “Stepova” mine, Lviv-Volyn region, are reported. The most effective granulometric composition of the water-coal suspension consisting of the rough and fine fractions is found from the analysis of the abovementioned physicochemical characteristics of the suspensions. Based on the complex investigation of the zeta potential of the dispersed phase particles, viscosity, and sedimentation stability of the suspensions, it was established that the best technological effectiveness can be expected for the suspensions containing 60% of the rough fraction (sized between 100 and 250 µm) and fine particles sized between 20 and 40 µm. In such systems, the particles form a quasi-stable structure, where the lower-charged small particles are located in the interparticle space between the highly charged bigger particles. All particles bear the same charge, increasing the system’s sedimentation stability and avoiding decomposition for at least 5 days. This time seems reasonable for the preparation, storage, and pumping of the suspensions while their viscosity and stability meet the relevant technological requirements.

Antifungal properties and molecular docking of ZnO NPs mediated using medicinal plant extracts

Significant postharvest losses and food safety issues persist in many developing nations, primarily due to fungal activities, including mycotoxin production. In this study, green synthesised zinc oxide nanoparticles (ZnO-NPs) were prepared from leaf extracts of Syzygium cordatum (ZnO 1), Lippia javanica (ZnO 2), Bidens pilosa (ZnO 3), and Ximenia caffra (ZnO 4). Physicochemical characteristics of the ZnO-NPs were determined using X-ray diffraction (XRD), Fourier transmission Infrared spectroscopy and ultraviolet–visible (UV–vis) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD analysis confirmed the presence of a wurtzite crystal structure in the hexagonal shape of the ZnO nanoparticles (NPs), with an average size ranging between 25 and 43 nm. The microscopic examination of the morphology revealed the presence of spherical particles with sizes ranging from 37 to 47 nm in diameter. The antifungal efficacy of the ZnO-NPs was assessed against pathogenic plant fungi, including Botrytis sp. (STEU 7866), Penicillium sp. (STEU 7865), and Pilidiella granati (STEU 7864), using the poisoned food technique. Further antifungal evaluation of the ZnOPs was performed using the broth microdilution assay. A significant interaction between the type of ZnO-NPs and fungal species was observed, with the highest susceptibility in Mucor sp. to ZnO 2, achieving over 50% inhibition. Penicillium sp. also showed high susceptibility to all ZnO-NPs. Molecular docking results confirmed the strong H-bonding interactions of ZnO-NPs with fungal receptors in Mucor sp. and Penicillium sp., Botrytis sp. and P. granati exhibited the least susceptibility. Further tests revealed that ZnO 2 exhibited the highest inhibitory effect on Botrytis sp., with a low minimum inhibitory concentration (MIC) of 25 µg/mL, attributed to its larger positive zeta potential. This study indicates that ZnO NPs, particularly those mediated using Lippia javanica (ZnO 2), have promising potential as effective antifungal agents, which could play a significant role in reducing postharvest decay and losses.

Visible light enhanced the degradation of sulfadiazine with persulfate activated by Cu2O@zeolite

ABSTRACT Cu2O/ZL-10 was successfully fabricated as a good activator of PDS and photo-catalyst. The physicochemical characteristics of the prepared Cu2O/ZL-10 were investigated. Cu2O/ZL-10 was employed to activate PDS for the sulfadiazine (SDZ) degradation under visible light irradiation. In the Vis/Cu2O/ZL-10/PDS system, 91.98% degradation rate of SDZ and 51.8% TOC removal after 180 min reaction were obtained. The SDZ degradation rate was improved significantly by the increase of the doping amount of Cu2O, PDS concentration and Cu2O/ZL-10 addition while it decreased with the growth initial pH. Moreover, the SDZ degradation rate descend by only 0.9% after five cycles uses of Cu2O/ZL-10. Quenching experiments and EPR spectra demonstrated that the dominant free radicals of •O2 –, SO4 •– and •OH were generated for the SDZ degradation. It demonstrated that Cu2O/ZL-10 was an effective and promising catalyst for the simultaneous activation of PDS and the utilization of visible light to generate active species and photo-induced electron, respectively.

Physicochemical and phytochemical characterization of opuntia dillenii: A promising source of bioactive compounds

ABSTRACT The objective of this ongoing research is to investigate and assess the aqueous extracts, vegetable oil, and residual plant components derived from O. dillenii by use of HPLC, and GC-MS. Subsequent investigations employed colorimetric techniques to identify reducing and soluble sugars. We developed and validated an energy-dispersive X-ray fluorescence (EDXRF) method for determining the concentrations of essential chemical elements (O, C, Ca, Mg, K, S, P) in seeds, juice, and peel, as well as their residues. HPLC analysis yielded results indicating that extracts from O. dillenii seeds, juice, and peel from distinct regions (Oujda, Nador, and Essaouira) contained elevated concentrations of metabolites. Specifically, peel and juice extracts exhibited the highest levels of organic acids and betanin compared to O. dillenii seeds. Conversely, seed oils displayed a noteworthy tocopherol content, predominantly δ-tocopherol. Similarly, an examination of organic acid composition in juice, peel, and seeds from three different regions revealed their elevated levels. Citric acid and oxalic acid emerged as predominant components in the juice. Overall, Opuntia dillenii’s physicochemical and phytochemical characterization improves in understanding its potential as a bioactive chemical promoter, which could lead to the creation of new medicinal medicines or functional food ingredients.

Impact of Harvesting Time on Grain Yield, Physicochemical Attributes, and 2-Acetyl-1-pyrroline Biosynthesis in Aromatic Rice

Achieving a consistent grain yield while preserving persistent aroma remains a substantial challenge in aromatic rice production in Bangladesh. To address this challenge, a field experiment was conducted at the agronomy research area of Sher-e-Bangla Agricultural University, Dhaka-1207, between 15 June 2022, and 25 November 2022 (Aman season). This study aimed to evaluate the influence of harvesting time on aromatic rice performance. The experiment, following a randomized complete block design with three replications, involved two factors: factor 1 comprised various rice varieties [Bangladesh Rice Research Institute (BRRI) dhan34, BRRI dhan70, BRRI dhan80, and Tulshimala], and factor 2 comprised three harvesting times [3, 4, and 5 weeks after flowering (WAF)]. Results revealed significant impacts of variety and/or harvesting time on grain yield, physicochemical characteristics, and aroma of aromatic rice. Notably, Tulshimala and BRRI dhan80 exhibited superior milling quality, biochemical properties, and aroma characteristics among the aromatic rice types. BRRI dhan70 and BRRI dhan80 displayed higher grain yield when harvested at 5 WAF. However, Tulshimala and BRRI dhan80 showed superiority in grain 2-acetyl-1-pyrroline (2-AP) concentration when harvested 3 or 4 WAF. Earlier harvesting at 3 and 4 WAF resulted in higher percentages of grain 2-AP (60.22% and 53.96%, respectively) compared with later harvesting at 5 WAF (used as check). In conclusion, varying harvesting times markedly impact the yield, physiochemical characteristics, and aroma of aromatic rice varieties, with earlier harvesting beneficial for aroma retention in Tulshimala and BRRI Dhan80 and later harvesting for increased economic yield in BRRI dhan70 and BRRI dhan80.

Pectic polysaccharides from Tartary buckwheat sprouts: Effects of ultrasound-assisted Fenton treatment and mild alkali treatment on their physicochemical characteristics and biological functions

Buckwheat sprouts are rich in pectic polysaccharides, which possess numerous health-improving benefits. However, the precise structure–activity relationship of pectic polysaccharides from Tartary buckwheat sprouts (TP) is still scant, which ultimately restricts their applications in the food industry. Hence, both ultrasound-assisted Fenton treatment (UAFT) and mild alkali treatment (MATT) were utilized for the modification of TP, and then the effects of physicochemical characteristics of original and modified TPs on their bioactivities were assessed. Our findings reveled that the UAFT treatment could precisely reduce TP’s molecular weight, with the levels decreased from 8.191 × 104 Da to 0.957 × 104 Da. Meanwhile, the MATT treatment could precisely reduce TP’s esterification degree, with the values decreased from 28.04 % to 4.72 %. Nevertheless, both UAFT and MATT treatments had limited effects on the backbone and branched chain of TP. Moreover, our findings unveiled that the UAFT treatment could notably promote TP’s antioxidant, antiglycation, and immunostimulatory effects, while remarkedly reduce TP’s anti-hyperlipidemic effect, which were probably owing to that the UAFT treatment obviously reduced TP’s molecular weight. Additionally, the MATT treatment could also promote TP’s immunostimulatory effect, which was probably attributed to that the MATT treatment significantly decreased TP’s esterification degree. Interestingly, the MATT treatment could regulate TP’s antioxidant and antiglycation effects, which was probably attributed to that the MATT treatment simultaneously reduced its esterification degree and bound phenolics. Our findings are conducive to understanding TP’s structure–activity relationship, and can afford a scientific theoretical basis for the development of functional or healthy products based on TPs. Besides, the UAFT treatment can be a promising approach for the modification of TP to improve its biological functions.

Synthesis and Characterisation of Nanocrystalline CoxFe1−xGDC Powders as a Functional Anode Material for the Solid Oxide Fuel Cell

The necessity for high operational temperatures presents a considerable obstacle to the commercial viability of solid oxide fuel cells (SOFCs). The introduction of active co-dopant ions to polycrystalline solid structures can directly impact the physiochemical and electrical properties of the resulting composites including crystallite size, lattice parameters, ionic and electronic conductivity, sinterability, and mechanical strength. This study proposes cobalt–iron-substituted gadolinium-doped ceria (CoxFe1-xGDC) as an innovative, nickel-free anode composite for developing ceramic fuel cells. A new co-precipitation technique using ammonium tartrate as the precipitant in a multi-cationic solution with Co2+, Gd3+, Fe3+, and Ce3+ ions was utilized. The physicochemical and morphological characteristics of the synthesized samples were systematically analysed using a comprehensive set of techniques, including DSC/TGA for a thermal analysis, XRD for a crystallographic analysis, SEM/EDX for a morphological and elemental analysis, FT-IR for a chemical bonding analysis, and Raman spectroscopy for a vibrational analysis. The morphological analysis, SEM, showed the formation of nanoparticles (≤15 nm), which corresponded well with the crystal size determined by the XRD analysis, which was within the range of ≤10 nm. The fabrication of single SOFC bilayers occurred within an electrolyte-supported structure, with the use of the GDC as the electrolyte layer and the CoO–Fe2O3/GDC composite as the anode. SEM imaging and the EIS analysis were utilized to examine the fabricated symmetrical cells.

Molecular Composition of Humic Acids and Soil Organic Matter Stabilization Rate of the First Arctic Carbon Measurement Supersite “Seven Larches”

In the framework of the implementation of the all-Russian climatic project “Carbon measurement test sites”, reference soils of “Seven Larches” carbon supersite, which is a benchmark and the only monitoring site in the Artistic latitudes, were investigated. The morphological structure of representative soils was specified, and it was found that soils are classified as Cryosols of different types (Histic, Stagnic or Gleyic). The basic physico-chemical characteristics of the soils were studied. By means of elemental analysis and 13C NMR spectroscopy, the composition and molecular structure of humic acids from organic and mineral soil horizons were studied. The surface (organic) soil horizons are characterized by high values of H:C molar ratios (1.2–1.3), which indicates a lower degree of the molecular structure aromaticity of humic acids from organic soil horizons. Analysis of the molecular structure of humic acids by 13C NMR spectroscopy showed that humic acids of the studied soils are characterized by the predominance of non-substituted aliphatic (0–47 ppm) and aromatic (108–164 ppm) fragments. Mineral soil horizons are characterized by higher stabilization of organic matter (with lower SOC content—0.5–0.9%) and higher hydrophobicity of humic acid molecules. Comparison of the obtained results with previously published data on the structural and elemental composition of humic acids isolated from soils of similar genesis and geographical location did not reveal any significant differences between the data obtained by us and previously published data. Thus, for “Seven Larches” carbon supersite “reference” parameters of elemental composition of humic acids, their molecular composition and degree of stabilization of soil organic matter were identified.

Artificial humic acid produced from wet distillers grains in a microwave-assisted hydrothermal process: Physicochemical characteristics and stimulation to plant growth

Wet distillers grains, as a waste biomass with a large annual output, pose a threat to the environment and food industry. Herein, artificial humic acid (AHA) was first produced from wet distillers grains in a dual-stage microwave-assisted hydrothermal process. The influence of temperature on AHA's characteristics was investigated and compared with natural humic acid (NHA) and standard humic acid (SHA). A high yield of AHA at 20.6% was obtained at 200 °C with a total reaction time of 1 h, which is 1.8–3.1 times that obtained in traditional single-stage hydrothermal process. Increasing the reaction temperature induced the formation of phenolic hydroxyl in AHA. AHA was rich in aromaticity and carboxylic acid structure, showing similar spectral characteristics to NHA. The distribution of molecular weight of AHA was mostly 5797 Da, which decreased by 15% compared to SHA. The optimal concentration of AHA to promote seedling growth was 0.2 g/L, and the root length was 2.0 times that of the control. The microwave hydrothermal process is a facile and efficient approach to preparing AHA from waste biomass with high moisture content.

Physicochemical and Nutritional Characterization of Green Banana Flour from Discarded Cavendish Bananas

Fifteen percent of harvested bananas are discarded daily in the Canary Islands at packing houses because of marketing standards, mainly based on their appearance, or are retired to avoid falls in the market price of bananas. This discarded fruit is an environmental issue, and green banana flour (GBF) is an interesting management alternative for it. In this paper, the artisanal process for obtaining GBF was optimized. The study of physicochemical and nutritional characteristics of this gluten-free flour indicated a high contribution of starch, fiber, phenolics, K, and Mg to dietary intake. Storage of GBF at room temperature (20 ± 5 °C) for ten months slightly increased its moisture and acidity and decreased its starch content, phenolic content, and pH. Some color changes were observed after 5 months, but sensory characteristics were still acceptable after ten months. Green bananas storage prior to GBF elaboration showed they were suitable for obtaining good quality GBF even after 7 weeks at 6 °C, but only 4 weeks at 12 °C. Discriminant analysis classified the GBF correctly according to the cooperative origin, time, and storage temperature of the bananas used in its preparation. These results provide information that could be used in other banana-producing regions for reducing the environmental impact of fruit waste and obtaining GBF using a simple and inexpensive technological process.

Tenebrio Molitor breeding rejects as a high source of pure chitin and chitosan: Role of the processes, influence of the life cycle stages and comparison with Hermetia illucens

This work valorizes rejects from Tenebrio Molitor TM breeding through the production of chitin and chitosan. Two processes are proposed for extracting chitin from larval exuviae and adult. The first process P1 provides chitin with high contents compared to literature data but the characterization shows the presence of impurities in the exuviae chitin responsible for the shifts in the values of the physicochemical characteristics towards those presented by γ chitin. These impurities are removed by delipidation and pure α chitin is obtained. The effective delipidation of this chitin would be linked to its fibrous surface structure. The analysis of the results of P1 led us to develop a second extraction process P2 which provides pure chitin with improved yields using delipidation followed by deproteinization. The N-deacetylation of chitin according to Kurita or Broussignac process makes possible the preparation of pure, highly deacetylated chitosan samples (2 % < DA < 12 %) with high yields and controlled molar masses (Mv). A kinetic study of molecular degradation during deacetylation is carried out. A comparison with Hermetia illucens allows to extend the use of insects as a potential source of chitin and chitosan and confirms the role of the source and the processes in the determination of their characteristics.