Physicochemical Research Articles

Investigating physicochemical properties of MgO catalysts for the gas phase conversion of glycerol

Investigating physicochemical properties of MgO catalysts for the gas phase conversion of glycerol

Roles of cigar microbes in flavor formation during roasted-rice leachate fermentation.

Roasted-rice leachate fermentation, a distinctive local tobacco fermentation method in Sichuan, imparts a mellow flavor and glossy texture to tobacco leaves, along with a roasted rice aroma. In order to find out the impact of roasted-rice leachate on cigar tobacco leaves, the physicochemical properties, volatile flavor profile, and microbial community were investigated. The content of protein significantly decreased after fermentation. The volatile flavor compounds increased following roasted-rice leachate fermentation, including aldehydes, alcohols, acids, and esters. High-throughput sequencing identified Staphylococcus, Pseudomonas, Pantoea, Oceanobacillus, Delftia, Corynebacterium, Sphingomonas, Aspergillus, Weissella, and Debaryomyces as the primary genera. Network and correlation analysis showed Debaryomyces played a crucial role in roasted-rice leachate fermentation, due to its numerous connections with other microbes and positive relationships with linoelaidic acid, aromandendrene, and benzaldehyde. This study is useful for gaining insight into the relationship between flavor compounds and microorganisms and provides references regarding the effect of extra nutrients on traditional fermentation products. KEY POINTS: • Volatile flavor compounds increased following roasted-rice leachate fermentation • Staphylococcus was the primary genera in fermented cigar • Debaryomyces may improve the quality of tobacco leaves.

Genome-Wide Identification of Pentatricopeptide Repeat (PPR) Gene Family and Multi-Omics Analysis Provide New Insights Into the Albinism Mechanism of Kandelia obovata Propagule Leaves.

Pentatricopeptide repeat (PPR) gene family constitutes one of the largest gene families in plants, which mainly participate in RNA editing and RNA splicing of organellar RNAs, thereby affecting the organellar development. Recently, some evidence elucidated the important roles of PPR proteins in the albino process of plant leaves. However, the functions of PPR genes in the woody mangrove species have not been investigated. In this study, using a typical true mangrove Kandelia obovata, we systematically identified 298 PPR genes and characterized their general features and physicochemical properties, including evolutionary relationships, the subcellular localization, PPR motif type, the number of introns and PPR motifs, and isoelectric point,and so forth. Furthermore, we combined genome-wide association studies (GWAS) and transcriptome analysis to identify the genetic architecture and potential PPR genes associated with propagule leaves colour variations of K. obovata. As a result, we prioritized 16 PPR genes related to the albino phenotype using different strategies, including differentially expressed genes analysis and genetic diversity analysis. Further analysis discovered two genes of interest, namely Maker00002998 (PLS-type) and Maker00003187 (P-type), which were differentially expressed genes and causal genes detected by GWAS analysis. Moreover, we successfully predicted downstream target chloroplast genes (rps14, rpoC1and rpoC2) bound by Maker00002998 PPR proteins. The experimental verification of RNA editing sites of rps14, rpoC1,and rpoC2 in our previous studyand the verification of interaction between Maker00002998 and rps14 transcript using in vitro RNApull-down assays revealed that Maker00002998 PPR protein might be involved in the post-transcriptional process of chloroplast genes. Our result provides new insights into the roles of PPR genes in the albinism mechanism of K. obovata propagule leaves.

Effect of Partial Replacement of Wheat Flour by Flour from Extruded Sunflower Seed Kernels on Muffins Quality.

The use of new types of raw materials to improve the quality and nutritional value of products is an important trend in flour confectionery. Flour from extruded sunflower seed kernels (FESSK), the by-product of oil production, was used as a new ingredient in muffin formulation. Analysis of physicochemical and nutritional properties of muffins prepared with FESSK, which was added in the amounts of 5, 10, and 15% to the total weight of mixture of wheat and rye flours, as well as their sensory evaluation, wereperformed. According to the sensory evaluation, the muffins with FESSK had a pleasant, nutty and sunflower aroma, and the best results were shown by muffins with 10% of FESSK. Addition of FESSK, 10%, led to an increase of the content of protein by 24.7%, fat by 16.9%, fiber by 23.3%, ash by 16.9%, and a decrease of content of total carbohydrates by 5.2% and sugars by 16.2%. Enriched muffins had improved texture characteristics, particularly, smooth, crack-free surface, soft, and elastic crumb with well-developed porosity and small, evenly distributed, thin-walled pores. The FESSK could be recommended as an ingredient for improving the nutritional and technological properties of flour confectionery products.

A compendium of all-in-one solar-driven water splitting using ZnIn2S4-based photocatalysts: guiding the path from the past to the limitless future.

Photocatalytic water splitting represents a leading approach to harness the abundant solar energy, producing hydrogen as a clean and sustainable energy carrier. Zinc indium sulfide (ZIS) emerges as one of the most captivating candidates attributed to its unique physicochemical and photophysical properties, attracting much interest and holding significant promise in this domain. To develop a highly efficient ZIS-based photocatalytic system for green energy production, it is paramount to comprehensively understand the strengths and limitations of ZIS, particularly within the framework of solar-driven water splitting. This review elucidates the three sequential steps that govern the overall efficiency of ZIS with a sharp focus on the mechanisms and inherent drawbacks associated with each phase, including commonly overlooked aspects such as the jeopardising photocorrosion issue, the neglected oxidative counter surface reaction kinetics in overall water splitting, the sluggish photocarrier dynamics and the undesired side redox reactions. Multifarious material design strategies are discussed to specifically mitigate the formidable limitations and bottleneck issues. This review concludes with the current state of ZIS-based photocatalytic water splitting systems, followed by personal perspectives aimed at elevating the field to practical consideration for future endeavours towards sustainable hydrogen production through solar-driven water splitting.

Thermal, structural, and sensory properties of tiger nut oil (Cyperus esculentus L.) – beeswax oleogels flavoured with butter and honey

AbstractThe aims of this study were to prepare butter and honey flavoured tiger nut oil oleogels with beeswax oleogelator and to compare them with the unflavoured control sample. The oleogels prepared with 10 wt% beeswax and 0.5 wt% of each flavour addition were analysed for main physicochemical, thermal, and structural properties. In addition, a trained panel described the samples with 11 sensory descriptive (hardness, spreadability, roasted, liquefaction, rancid, waxy, nutty, butter, honey, cooling, and mouth coating) terms. It was found that the oleogels melt around 52 °C and included β′ type polymorphs. The sensory data proved that the samples were quite well spreadable and had enough hardness to stay as solid-fat samples at room temperature. Further, addition of butter and honey flavours masked the waxy attribute. In conclusion, flavoured tiger nut oil-beeswax oleogels were new and successful products, and future studies with food applications are suggested.

Effects of pH on coprecipitation of As(III) with biogenic synthesized schwertmannite and jarosite.

Secondary iron minerals play significant roles in the immobilization of As under acidic conditions, such as acid mine drainage. However, previous research works have not clarified the effect of pH on As(III) removal through coprecipitation with secondary minerals. Therefore, in this study, we aimed to investigate the discrepancy in As(III) coprecipitation with biogenic synthesized schwertmannite (Sch) and jarosite (Jar) at different pH values. For this, concentrations of Fe2+, TFe, , and As(III) in shake flasks were monitored during an overall incubation period of 83 h at initial pH of 1.5, 2.0, and 2.5. In addition, the physicochemical properties of collected minerals after incubation were identified using scanning electron microscopy, X-ray diffraction, pore size distribution, and Brunauer - Emmett - Teller surface area analyses. Our results showed that almost no mineral synthesis and no As(III) removal were detected in coprecipitated schwertmannite (Co-Sch) system and coprecipitated jarosite (Co-Jar) system at an initial pH of 1.5. The TFe precipitation efficiencies and As(III) removal efficiencies increased considerably and morphologies of Co-Sch and Co-Jar improved significantly when the initial pH value increased from 2.0-2.5. The maximum TFe precipitation efficiency and As(III) removal efficiency reached 30.8% and 89.6%, respectively, for the Co-Sch system, and were 47.5% and 37.4%, respectively, for the Co-Jar system. The overall results show that pH significantly affects the formation of Co-Sch and Co-Jar and the behaviour of As(III) coprecipitation.

A shape-stable phase change material for high-temperature thermal energy storage based on coal fly ash and Na2SO4-K2SO4

Using coal fly ash (CFA) as the skeleton material and binary sulfates of Na2SO4-K2SO4 as the phase change material (PCM), high-temperature coal fly ash based phase change thermal storage materials (CPCM) were successfully synthesized. The influences of CFA fractions and types on the morphology, physicochemical properties, and thermal characteristics of the composites were intensively investigated. Results show that the heat storage density and thermal conductivity of CPCMs increase with the PCM content. Particularly, the CPCM60-A composite, comprising 60 wt% Na2SO4-K2SO4 eutectic and 40 wt% CFA-A, exhibits excellent chemical compatibility and stable shape retention after sintering. Furthermore, CPCM60-A demonstrates the highest phase change latent heat of 60.43 J/g and thermal conductivity of 0.61 W/(m·K). The influence of CFA types reveals that CFA-A with a higher ratio of SiO2 and Al2O3, lower carbon content, and a rich porous structure is more suitable to fabricate molten salt heat storage materials. This work demonstrates that CFA, a byproduct of coal-fired industry, is a promising skeleton material for the fabrication of high-temperature CPCM composites, offering a novel approach for enhancing the efficiency and cost-competitiveness of solar power and waste heat recovery systems.

In silico Identification of MHC Displayed Tumor Associated Peptides in Ovarian Cancer for Multi-Epitope Vaccine Construct.

Recognizing the potential of the immune system, immunotherapies have brought about a revolution in the treatment of cancer. Low tumour mutational burden and strong immunosuppression in the peritoneal tumor microenvironment (TME) lead to poor outcomes of immune checkpoint inhibition (ICI) and CART cell therapy in ovarian cancer. Alternative immunotherapeutic strategies are of utmost importance to achieve sound clinical success. The development of peptide vaccines based on tumor-associated antigens (TAAs) for ovarian cancer cells can be a potential target to provoke an anti-tumor immune response and subsequent clearance of tumour cells. The purpose of this in-silico study was to find potential epitopes for a multi-epitope vaccine construct using the immunopeptidomics landscape of ovarian carcinoma. The four TAAs (MUC16, IDO1, FOLR1, and DDX5) were selected as potential epitopes for B-cells, helper T-lymphocytes (HTLs), and cytotoxic T-lymphocytes (CTLs) predicted on the basis of antigenic, allergenic, and toxic properties. These epitopes were combined with suitable linkers and an adjuvant to form a multi-epitope construct. Four HTLs, 13 CTLs, and 6 potential B-cell epitopes were predicted from the TAAs. The designed multi-epitope construct was potentially immunogenic, non-toxic, and nonallergenic. Physicochemical properties and higher-order structural analyses of the final construct revealed a potential vaccine candidate. The designed vaccine construct has the potential to trigger both humoral and cellular immune responses and may be employed as a therapeutic immunization candidate for ovarian malignancies. However, further in vitro and animal experimentation is required to establish the efficacy of the vaccine candidate.

Physicochemical Properties, Heavy Metal and Pesticide Contaminations, and Microbial Limit Tests of Cannabis Oral Drops

Cannabis, a medicinal herb renowned for its therapeutic potential, is utilized in the treatment of various ailments, including the stimulation of appetite in cancer patients. In Thailand, the predominant dosage form is oral drops; however, the absence of robust quality control measures for these products poses significant health risks to patients. The primary objectives of this study were to formulate and evaluate cannabis oral drops, with a comprehensive evaluation encompassing physicochemical properties such as appearance, pH, Δ9-tetrahydrocannabinol, and cannabidiol contents. Furthermore, heavy metals (specifically arsenic, cadmium, and lead), pesticides (including pyrethroids, organochlorines, organophosphates, and carbamates), and microbial contaminations (Staphylococcus aureus, Clostridium spp., and Salmonella spp.) were evaluated. The results revealed that the optimal formulation, comprising cannabis extract derived from supercritical carbon dioxide fluid, vitamin E acetate, and medium-chain triglyceride oil, exhibited a pH of approximately 4.0, a Δ9-tetrahydrocannabinol content of approximately 27 mg/mL, and a cannabidiol content of approximately 9 mg/mL. Furthermore, there were no heavy metals or pesticides detected. Microbial limit tests demonstrated the absence of Staphylococcus aureus, Clostridium spp., and Salmonella spp. In conclusion, this endeavor successfully achieved the development of high-quality cannabis oral drops, showcasing the potential for safe and therapeutic use.

Preparation and Analysis of Physicochemical Properties, Antioxidant and Antibacterial Activities of Kombucha Tea Produced from Beijing Bamboo Leaf Tea (Dendrocalamus sp.) and Green Tea

Beijing bamboo (Dendrocalamus sp.), belonging to the Poaceae family, has been largely neglected and underutilized, particularly its leaves. This study aims to investigate the physicochemical properties, antioxidant, and antimicrobial activities of Beijing bamboo leaf and Beijing bamboo leaf kombucha. Hot air drying was conducted at temperatures of 60, 65, and 70ºC, with results indicating that 65ºC is the optimal drying temperature for achieving the highest levels of total phenolic compounds, flavonoids, and antioxidant activities. Beijing bamboo leaf tea underwent a 21-day fermentation process with a kombucha consortium comprising yeasts and acetic acid bacteria. The results showed that the changing trends of pH, total acidity, and total soluble solids were similar between kombucha produced from Beijing bamboo leaf tea and green tea. Fermentation notably enhanced the antioxidant activity of the kombucha, as evidenced by DPPH and FRAP assays, which correlated with increases in phenolics and flavonoids. The antimicrobial efficacy was assessed through the agar diffusion method and minimum inhibitory concentration (MIC), revealing that both Beijing bamboo leaf tea and green tea suppressed the growth of pathogenic bacteria, including Salmonella Typhimurium DMST 562, E. coli DMST 4242, Bacillus cereus DMST 5040, Staphylococcus aureus DMST 8840, and Pseudomonas aeruginosa DMST 4739. Notably, kombucha from green tea exhibited superior antimicrobial effects compared to Beijing bamboo leaf tea kombucha. Additionally, fermentation of Beijing bamboo leaf tea resulted in higher counts of yeast, acetic acid bacteria, and lactic acid bacteria throughout the fermentation process than those observed in green tea kombucha. These findings highlight the potential of Beijing bamboo leaves as a valuable resource for developing functional properties in underutilized plant resources, offering promising applications in the food and health industries.

Pirtobrutinib: First Non-covalent Tyrosine Kinase Inhibitor for Treating Relapsed or Refractory Mantle Cell Lymphoma in Adults.

Mantle Cell Lymphoma (MCL) is an aggressive subtype of Non-hodgkin's Lymphoma (NHL). Bruton Tyrosine Kinase (BTK) is a non receptor tyrosine kinase, and is one of the therapeutic targets for B-cell-driven malignancies. Approved covalent BTK inhibitors such as ibrutinib, acalabrutinib, and zanubrutinib are associated with treatment limitations due to off-target side effects and the development of C481 substitution resistance mutations. Pirtobrutinib was approved by the US FDA on January 27, 2023, for the treatment of relapsed or refractory mantle cell lymphoma, including the resistance to covalent BTK inhibitors. In this perspective, physicochemical properties, synthesis, dosage and administration, mechanism of action, pharmacodynamics, pharmacokinetics, drug interactions, and treatment-emergent adverse events of pirtobrutinib are discussed.

Molecular Surface Description of Halomethanes and its Relation to Their Physicochemical Properties: A Quantum Chemical Investigation

Molecular Surface Description of Halomethanes and its Relation to Their Physicochemical Properties: A Quantum Chemical Investigation

The eutectic and physicochemical properties of the carboxylic-acid-based deep eutectic solvents

The excellent performance of the deep eutectic solvent (DES) is consistent with the 12 Principles of Green Chemistry. It is of importance to study the DES’s structural characteristics, thermophysical properties and physicochemical properties, especially the DES’s solid–liquid-equilibrium phase diagrams in the entire mole fraction. In this work, ten DES were prepared using tetrabutylammonium bromide as the hydrogen bond acceptor, and octanoic acid/hexanoic acid as the hydrogen bond donors. The molar ratio ranged from 1:1.25 to 1:4. Then, the solid–liquid-equilibrium phase diagrams were obtained. The eutectics and the corresponding eutectic points were discovered. The nuclear magnetic resonance spectra and the Fourier transform infrared spectra were applied to analyze the interactions in DES. The densities and viscosities of the prepared DES were measured. With the optimized Lydersen-Joback-Reid method combined with Lee-Kesler rules, the critical properties were predicted. And then the results were verified through a density prediction model. The average absolute relative deviation (AARD) is better than 1.38%. The mass-connectivity-index-based model was introduced for density prediction with AARD of less than 0.17%. For the viscosity, the Arrhenius equation was compared with an equation considering the molar mass. The AARD of them were less than 2.68 % and 0.69 %, respectively.

Enhancement effect of kale fiber on physicochemical, rheological and digestive properties of goat yogurt

This study incorporated kale fiber into goat milk as a functional component to investigate its impact on the quality and functional characteristics of set goat yogurt. Kale fiber content ranging from 0% to 1.5% (w/v) was added to 15% (w/v) defatted goat milk powder dissolved in water to form set yogurt. The addition of fiber increased the particle size and absolute potential of the goat yogurt, with a positive correlation observed between yogurt hardness, cohesiveness, and fiber content. Optimal water retention and thermal stability were achieved at a 0.5% fiber concentration. Microscopic analysis confirmed the successful incorporation of kale fiber into the yogurt gel network, resulting in significant differences in gel structure based on varying fiber content. Oscillatory temperature scan results indicated enhanced resistance to temperature changes due to the inclusion of kale fiber. Additionally, thixotropy results showed a 10% to 30% increase in gel structure recovery rate compared to the control group. In vitro digestion studies confirmed that kale fiber significantly improved protein bioavailability and release rate during digestion. Thus, incorporating kale fiber into goat milk as a natural plant-based functional component can enhance its nutritional value and rheological properties.

Physicochemical, Morphological and Anticorrosive Properties of Electrodeposited ZnNi Alloy Coating

Corrosion in its many forms is a major problem for many types of materials, extending from machining to manufacturing and daily use. In fact, it affects practically all engineering projects, from the biggest to the smallest: energy production, construction, transport, medical sector, electronics, etc. Consequently, corrosion generates both economic and environmental problems. To prevent corrosion and preserve materials' durability, several protection methods can be applied. These included protection by applying a coating on the metal surface. In this context, Zinc based alloy coatings have attracted much interesting scientific community because of their excellent mechanical and anti-corrosive properties. In the present work, ZnNi coatings were electrodeposited on steel substrates using a chloride bath containing ammonium salts. The effect of some experimental parameters, namely, potential and metal ion concentration ratio on the deposition kinetics of ZnNi system as well as on its physicochemical, morphological and anticorrosive properties has been investigated. For this purpose, an appropriate experimental work was performed by using both electrochemical (cyclic voltammetry, chronoamperometry, open circuit potential, potentiodynamic polarization) and nonelectrochemical (SEM-EDX) analysis methods. Based on the obtained results, it has been revealed that simultaneous codeposition of both elements Zn and Ni is possible in our experimental conditions. However, deposition kinetics exhibited a strong dependence on explored parameters. Also, morphological aspect and chemical composition of deposits are strongly influenced by metal ion concentration ratio. Investigation of corrosion behaviour confirms the protective effect of coatings acted as a sacrificial anode. Furthermore, increasing Ni content in the deposits induces a significant enhancement in corrosion resistance. Thus, Zn-Ni alloy coatings prepared from the Ni(II)-rich bath exhibited better corrosion resistance.

Effect of Defatted Rice Bran Content on Physicochemical and Sensory Properties of Edible Cutlery Made from Rice Flour Green Composites using Compression Molding

The optical properties, moisture content, water activity, water absorption, mechanical properties, morphological observations, and sensory properties of edible spoons made from rice flour and rice flour green composites were investigated. The rice flour green composites were prepared with different weight ratios of rice flour and defatted rice bran as 100:0, 75:25, 50:50, and 25:75 by compression molding at 150°C at a fixed pressure of 9 bar for 7 min. Increasing the weight proportion of defatted rice bran in rice flour green composites resulted in higher lightness values, yellowness values, and water absorption, but redness values and moisture content decreased. Weight proportions of defatted rice bran in rice flour green composites up to 50 improved mechanical properties (both Izod impact and flexural strength). The cross-sectional surface after flexural testing of rice flour spoons was smooth, whereas rice flour green composite spoons were rough. Sensory properties of rice flour green composite spoons showed reduced appearance scores, color scores, texture scores, and overall preference scores but odor scores increased compared with rice flour spoons. Maximum compression force of rice flour green composite spoons increased with increasing weight proportion of defatted rice bran. An increase in maximum compression force measured by the mechanical testing equipment was related to a decrease in texture scores. Spoons made from rice flour and rice flour green composites showed promise as single-use edible cutlery and packaging.

Microscopic and macroscopic analysis of hexavalent chromium adsorption on polypyrrole-polyaniline@rice husk ash adsorbent using statistical physics modeling

This paper contributed with new findings to understand and characterize a heavy metal adsorption on a composite adsorbent. The synthesized polypyrrole–polyaniline@rice husk ash (PPY–PANI@RHA) was prepared and used as an adsorbent for the removal of hexavalent chromium Cr(VI). The adsorption isotherms of Cr(VI) ions on PPY–PANI@RHA were experimentally determined at pH 2, and at different adsorption temperatures (293, 303, and 313 K). Multi-layer model developed using statistical physics formalism was applied to theoretically analyze and characterize the different interactions and ion exchanges during the adsorption process for the elimination of this toxic metal from aqueous solutions, and to attribute new physicochemical interpretation of the process of adsorption. The physicochemical structures and properties of the synthesized PPY–PANI@RHA were characterized via Fourier transform infrared spectroscopy (FTIR). Fitting findings showed that the mechanism of adsorption of Cr(VI) on PPY–PANI@RHA was a multi-ionic mechanism, where one binding site may be occupied by one and two ions. It may also be noticed that the temperature augmentation generated the activation of more functional groups of the composite adsorbent, facilitating the interactions of metal ions with the binding sites and the access to smaller pore. The energetic characterization suggested that the mechanism of adsorption of the investigated systems was exothermic and Cr(VI) ions were physisorbed on PPY-PANI@RHA surface via electrostatic interaction, reduction of Cr(VI) to Cr(III), hydrogen bonding, and ion exchange. Overall, the utilization of the theory of statistical physics provided fruitful and profounder analysis of the adsorption mechanism. The estimation of the pore size distribution (PSD) of the polypyrrole-polyaniline@rice husk ash using the statistical physics approach was considered stereographic characterization of the adsorbent (here PPY–PANI@RHA was globally a meso-porous adsorbent). Lastly, the mechanism of Cr(VI) removal from wastewater using PPY-PANI@RHA as adsorbent was macroscopically investigated via the estimation of three thermodynamic functions.

Evaluation of Physicochemical and Rheological Properties of Terminal Blend Rubberized Asphalt Incorporating Polymer

Evaluation of Physicochemical and Rheological Properties of Terminal Blend Rubberized Asphalt Incorporating Polymer

Decomposer faecal food web and C sequestration in soil. Can near infrared spectroscopy describe transfers and transformations from fresh organic inputs to protected forms in soil aggregates?

This study sought to characterize the transfer of agricultural organic inputs by macrofauna to the biogenic aggregate compartments of the soil and test the existence of a faecal food web process based on coprophagic feeding behaviours. In an experimental plantain crop field of Colombia, we applied the agroecological FBO (Fertilisation Bio Organique ®) technology, a nucleation technique which consists in planting perennial plants in 1.0 x 0.4 × 0.4 m deep trenches where low- and high-quality organic materials are added in a specific design, and endogeic earthworms are inoculated. We evaluated the effectiveness of Near Infrared Spectroscopy (NIRS) to track this flow of organic matter through different natural stages of decomposition represented by soil macroaggregates produced by soil macroinvertebrates as faecal pellets and casts. After one year, great part of the organic inputs had been either mineralized or incorporated into macroaggregates of different sizes and origins. Using NIRS and physicochemical laboratory analyses, we assessed the quality and quantity of organic matter in the different types of aggregates separated manually according to their origin: large biogenic aggregates (LBA), medium sized biogenic aggregates (MBA) and small biogenic aggregates (SBA); physical aggregates (PA), root aggregates (RA) and residual soil (RS).Earlier studies had shown that these structures were presumably formed by the activity of macroinvertebrates of three different functional groups, Diplopoda and Isopoda litter transformers for SBA, epidendogeic earthworms for MBA and mesohumic endogeic earthworms for LBA, organized in a feeding succession.A Coinertia analysis between showed significant covariation among the two sets of physico chemical (22 variables) and NIR spectral (100 different wavelength absorbances) characterization of 135 samples representative of the three classes of biogenic macroaggregates, physical aggregates and residual non macroaggregated soil, (RV = 0.55; p < 0.001). This analysis clearly separated biogenic structures and ranked them according to their size, from small SBA to medium sized MBA and large LBA. Physical PA aggregates and RS residual soil were projected close to the LBAs in the coinertia factorial plan. Multiple combinatorial data analysis CDA, associated 5 specific wavelength absorbance ranges with aggregate types and residual soil. Along the sequence from small to large biogenic aggregates, residual soil and physical aggregates, wavelengths associated to easily decomposed substrates (in ranges 1708–1716 nm; 1796–1948 and 2164–2316 nm) had progressively decreasing absorbances. Substrates associated to slowly decomposing aromatic, alkane and phenolic substrates either increased (1420–1436) or decreased (1284–1380) along this sequence.These results are compatible with the hypothesis of a progressive transformation and transfer of organic residues first into small biogenic aggregates that are presumably faecal pellets of Isopoda and Diplopoda, then to medium sized biogenic aggregates identified as casts of epiendogeic earthworms and finally to large biogenic aggregates expected to be the casts of the large endogeic earthworms present in these soils. A definitive verification of the hypothesis and the involvement of specific macroinvertebrates will require direct experimentation in controlled laboratory conditions.