Search Results (248)

Camu-camu (Myrciaria dubia) is an Amazonian shrub associated with riverine ecosystems and is recognized for its high vitamin C content and a broad range of nutritional and specialized metabolites. Previous studies have focused on specific metabolites or bioactive metabolites associated with health issues. Therefore, a comprehensive metabolomic survey using multiple analytical methods islacking. To address this gap in the scientific literature, we prepared a focused metabolomic inventory by integrating curated literature records with proton nuclear magnetic resonance (¹H NMR) and liquid chromatography–mass spectrometry (LC-MS) observations from berry materials, including pulp, skin/peel, and seeds. Ourstudy added 107 metabolite annotation records that were not in the literature. The integration of the literature-derived and ourdatasets yielded a combined inventory of 260 metabolites. Seven solvents were compared using ¹H NMR spectroscopy, and CH₃OH:CD₃OD (9:1, v/v) provided the broadest assigned coverage. LC-MS expanded the detection of lower-abundance and structurally diverse features, particularly phospholipids, quaternary ammonium compounds, organic acids, amino acid derivatives, and related metabolites. Compound-level and class-level assignments were distinguished, and interpretations were limited to the confidence supported by the available analytical evidence. The resulting inventory provides an expanded foundation for camu-camu quality evaluation, solvent selection, clinical trials, and targeted functional food research. Full article

The selective separation of chalcopyrite from pyritic ores represents a major industrial challenge due to inadvertent copper activation. This study systematically investigates the batch flotation kinetics of a complex sulfide ore (Draa Sfar North, Morocco) using a first-order kinetic model ($R^2>0.916$). The impacts of pulp pH, chemical depressants, and specialized collectors were evaluated to optimize the copper/iron selectivity index ($S{I}_{Cu/Fe}$). The results reveal a high-alkalinity paradox: At pH 11.0, chalcopyrite kinetics experience a severe passivation bottleneck ($K_{i,Cu}=0.1330 {\min }^{-1}$). At pH 11.5, selectivity collapses ($SI=2.64$) due to persistent iron sulfide floatability ($K_{i,Fe}=0.2066 {\min }^{-1}$). Conversely, natural pH ($\approx 6.0$) provides a superior baseline ($SI=3.32$), where 40 g/t sodium cyanide (NaCN) yielded a peak index of $S{I}_{Cu/Fe}=10.25$. As an eco-friendly substitute, sodium lignosulfonate (LSNa) achieved outstanding performance ($S{I}_{Cu/Fe}=5.30$), reducing iron kinetics to their lowest level ($K_{i,Fe}=0.0356 {\min }^{-1}$) via ferric–anionic complexation. Furthermore, Danafloat 271 secured the highest collector-driven selectivity ($S{I}_{Cu/Fe}=5.03$) by suppressing the iron matrix ($K_{i,Fe}=0.0306 {\min }^{-1}$) following Hard–Soft Acid–Base principles. This study clarifies specific aspects of selective copper–iron flotation, demonstrating that natural pH circuits with green depressants or selective collectors offer a sustainable alternative. Full article

This study evaluated the applicability of tumbo (Passiflora tripartita var. mollissima) seeds for oil extraction by expeller pressing and characterized the resulting oil in terms of physicochemical quality, fatty acid profile, and in vitro antioxidant properties. The nutritional composition of tumbo fruit fractions, including pulp, peel, seeds, and residual seed cake, was also assessed. Tumbo seed oil showed a pressing yield of 16.78% and was characterized by a predominance of polyunsaturated fatty acids, mainly linoleic acid, together with low acid and peroxide values and a high iodine value. The oil also showed measurable in vitro antioxidant capacity in ABTS, DPPH, and FRAP assays, along with relevant total phenolic content (TPC) and total flavonoid content (TFC). These findings provide baseline information on tumbo seed oil as a non-conventional Andean fruit seed oil and suggest potential interest for future technological and food-related studies. Further research is required to evaluate its oxidative stability, safety, detailed bioactive compound profile, and potential biological effects before proposing specific functional or health-related applications. Full article

Gardenia sootepensis Hutch. (Golden Gardinia) has received limited scientific attention despite the chemical diversity of its specialized metabolites. In this study, aqueous and 70% ethanolic preparations derived from the leaves, peel plus pulp, and seeds were systematically evaluated for extraction efficiency, total phenolic content (TPC), flavonoid content (TFC), ABTS and DPPH radical-scavenging capacity, HPLC–ESI–MS phytochemical profiles, and cytocompatibility with C28/I2 cells and primary human articular chondrocytes. The largest extract recovery was obtained from seed material, whereas the ethanolic leaf preparation contained the greatest TPC (81.08 ± 4.60 mg GAE/g), and TFC (28.36 ± 3.63 mg QE/g), and showed the strongest ABTS antioxidant activity (272.92 ± 10.95 mg TE/g). HPLC–ESI–MS analysis based on nominal-mass measurements enable the provisional annotation of 34 phytochemical features encompassing iridoids and iridoid glycosides, phenolic acids, flavonoids and their glycosides, xanthones, and benzophenone-related constituents. Overall, extraction with aqueous ethanol yielded a wider spectrum of detectable metabolites than extraction with water, while seed-derived preparations displayed the greatest chemical diversity. Under the experimental conditions and concentration range tested, viability of both immortalized C28/I2 cells and primary human articular chondrocytes remained above 80%. Collectively, these findings demonstrate that the botanical tissue selected and the extraction solvent substantially influence the phytochemical composition and antioxidant properties of G. sootepensis. The observed cytocompatibility provides a basis for subsequent mechanistic investigations but does not establish chondroprotective activity. Further confirmation and quantitative characterization of the provisionally annotated metabolites using high-resolution MS/MS and authentic reference standards are warranted. Full article

The production of second-generation bioethanol from lignocellulosic biomass requires efficient enzymatic hydrolysis and fermentation processes that remain effective at industrially relevant solids loadings. In this study, bleached Pinus taeda kraft pulp was evaluated as a model substrate for bioethanol production at bench scale (4 L reactor) under high-consistency conditions (12.5–13.9% solids). Three process configurations were compared: separate hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF), and pre-hydrolysis followed by simultaneous saccharification and fermentation (pSSF). Enzymatic hydrolysis in the SHF and SSF configurations stabilized between 54% and 58%, indicating that hydrolysis was the main process bottleneck under the evaluated conditions. In contrast, Saccharomyces cerevisiae efficiently fermented the available glucose, achieving nearly complete conversion of glucose. Among the evaluated strategies, pSSF showed the highest ethanol yield and volumetric productivity, achieving an ethanol yield of 61.8% and a productivity of 0.61 g L⁻¹ h⁻¹. While laboratory-scale SSF experiments conducted at 2% solids achieved complete conversion, the ethanol yield decreased to approximately 58% at the bench scale, highlighting the impact of high-solids operation on process performance. The lower performance observed at high solids may be associated with factors commonly reported during scale-up, including increased slurry viscosity, reduced mixing efficiency, limited enzyme accessibility, and mass-transfer constraints. Overall, the results manifest the need to enhance hydrolysis performance through improved reactor design, more effective mixing strategies, and optimized high-solids processing to facilitate the scale-up of lignocellulosic bioethanol production. Full article

Black rice wine is a traditional cereal-based fermented beverage valued for its colour, flavour and bioactive constituents. However, product innovation is needed to meet increasing consumer demand for fruit-derived aroma, nutritional quality and functional attributes. To address this demand, we developed an integrated processing strategy combining enzymatic pretreatment of pitaya pulp with stage-specific co-fermentation, an approach that has not been systematically evaluated in rice wine systems. Pitaya pulp was first pretreated with pectinase using an orthogonal design to optimise juice yield and betacyanin retention; the enzymatically pretreated pitaya pulp was then introduced either as pulp or as fermented pitaya wine at the saccharification, tank-flushing or ageing stage. The resulting wines were compared with a pitaya-free control and three commercial black rice wines on the basis of physicochemical indices, phenolic and pigment contents, amino acid composition, mineral composition and fuzzy mathematics-based sensory evaluation. Pitaya pulp added at saccharification (Sample THJ) yielded the strongest functional and nutritional profile, with the highest total phenolic content (629.74 mg/L); high flavonoid content (152.07 mg/L); enrichment in Mg, K and Mn; and a broader taste-active amino acid profile. By contrast, pitaya pulp added during tank flushing (Sample CHJ) achieved the highest sensory score (85.3) and had the highest anthocyanin content. These findings indicate that the timing and form of pitaya addition determine the balance between functional enrichment, pigment retention and sensory quality. Co-fermentation with red-fleshed pitaya, particularly the early addition of enzymatically pretreated pitaya pulp, provides a practical route for the development of fruit-flavoured black rice wine with improved nutritional composition and consumer appeal, suggesting the potential for enhanced functional value. Full article

Background/Objectives: Pulp necrosis in immature permanent teeth arrests root development, leaving an open apex, thin, divergent dentinal walls, and an unfavorable crown-to-root ratio that predisposes the tooth to fracture and complicates endodontic management. An apical barrier using hydraulic calcium silicate cements has become the first-line orthograde approach for these teeth when regenerative procedures are not indicated or feasible. This narrative review synthesizes current evidence on the complete clinical pathway for apical barrier placement in immature permanent teeth, with particular emphasis on the procedural determinants of barrier formation. It also critically appraises where the evidence is robust and where it remains uncertain. Methods: The relevant English-language literature on root development, the etiology of pulp necrosis in immature teeth, diagnosis, isolation, apical barrier methods, calcium silicate materials, and treatment outcomes was reviewed through targeted searches of PubMed/MEDLINE, Scopus, Web of Science, the Cochrane Library, and Google Scholar through June 2026. The literature search was completed in June 2026; therefore, studies published after this date were not included. Evidence was narratively synthesized according to the clinical sequence of diagnosis, treatment selection, isolation, disinfection, barrier formation, restoration, follow-up, and evidence gaps. Throughout, an explicit distinction was maintained between clinical and laboratory evidence. Results: Sensibility testing is widely considered unreliable in immature teeth, complicating diagnosis. Isolation is often challenging because of traumatic crown loss. Successful treatment depends on adequate chemical disinfection, judicious minimal instrumentation, a well-condensed apical barrier of at least 4–5 mm, and a definitive coronal seal that also addresses the weak cervical dentin. Calcium silicate cements—principally MTA, Biodentine, and pre-mixed bioceramic putties—achieve high clinical success. Observational evidence further suggests, as a hypothesis requiring prospective confirmation, that material choice may be less decisive than operator experience and the quality of the coronal restoration. Conclusions: Apical barrier placement with hydraulic calcium silicate cements is a predictable orthograde preservation approach for non-vital immature permanent teeth, particularly when regenerative endodontic procedures are not indicated, not feasible, or unlikely to yield predictable clinical outcomes. Well-designed randomized clinical trials with standardized reporting are needed. Full article

Flotation of mixed copper oxide–sulfide ores remains challenging due to low natural floatability of oxide minerals and complex interplay between sulfidization and collector adsorption. This study investigated the combined effect of NaHS-assisted sulfidization and 2,5-dimercapto-1,3,4-thiadiazole (DMTD), an azole-based collector, in terms of enhancing copper recovery from a mixed oxide–sulfide ore. The effects of pulp pH, DMTD, NaHS, and sodium metasilicate dosages, together with pulp solid concentration, were evaluated using response surface methodology. The quadratic model showed high predictive capability (R² = 0.9361), identifying NaHS dosage as the most influential factor. Optimum operating conditions (pH 9.50, DMTD 200 g/t, NaHS 750 g/t, sodium metasilicate 500 g/t, and 25% solids) yielded 64.03% copper recovery. Compared with the plant collector (PAX, Potassium Amyl Xanthate), DMTD increased recovery by 12.6% for highly oxidized ore while producing a higher concentrate grade. Density Functional Theory (DFT) calculations provided molecular insights into the experimental observations, confirming DMTD’s high affinity for sulfidized surfaces. Hybrid solvation models revealed greater thermodynamic stability (ΔE_ads = −6.74 eV) than PAX due to hydrogen bonding with explicit water molecules, while the smaller HOMO–LUMO gap (ΔE_gap = 0.86 eV) supported its superior electron transfer capability and reactivity. These findings demonstrate that NaHS-assisted sulfidization with DMTD is an effective strategy for improving flotation of copper oxide–sulfide ores. Full article

The escalating volume of agricultural waste presents not only a significant environmental challenge but also a substantial opportunity for resource recovery within a circular bioeconomy. This study investigates the feasibility of extracting high-quality cellulose from two underutilized agricultural residues: flower stems and tomato stems. Raw materials were subjected to a multi-stage chemical pulping process involving alkaline treatment, acid treatment, and hydrogen peroxide bleaching in order to remove lignin, hemicellulose, and other impurities. The resulting cellulose samples were comprehensively characterized for their yield, purity (α-cellulose content), degree of polymerization (DP), chemical structure (FT-IR), crystallinity (XRD), and inorganic elemental composition. The results demonstrate that both feedstocks can yield cellulose with an α-cellulose content exceeding 91% and a DP greater than 600, meeting the stringent quality requirements for dissolving-grade pulp intended for such applications as textiles, composite additives and others products. Flower stems showed a higher pulping yield (26.8%) compared to tomato stems (13.7%), highlighting their greater potential. This work validates agricultural residues, particularly flower stems, as a viable and sustainable alternative to traditional wood sources for cellulose production, offering a pathway to mitigate waste and add value to agricultural supply chains. Full article

The efficient utilization of natural resources and agricultural wastes aligns well with the UN Sustainable Development Goals. Sunflower seed husks are an affordable and renewable source of cellulose that can be used as an alternative to wood-based resources. However, the yield and quality of cellulose are affected by the presence of components such as phytomelanin, hemicellulose, and lignin. In this study, cellulose pulp (CP) was extracted from untreated, water-treated, and water and alkali-treated SFH. The optimal peroxyacetic acid (PAA) to biomass ratio was established to assess the influence of pre-treatment on CP properties. Water and alkali pre-treatments significantly increased CP yield and reduced residual lignin, hemicellulose, and ash compared to untreated samples. The optimal yield of CP for SFH-NaOH was 55.73%. All microcrystalline cellulose (MCC) types exhibited comparable α-cellulose content, confirmed by the IR band at 1430 cm⁻¹. XRD showed lower crystallinity in untreated CP-SFH relative to pre-treated samples. SEM revealed porous fibrous structures across all MCCs. Pre-treatment also improved the thermal stability and ζ-potential of cellulose nanocrystals (CNCs) obtained from MCC, without altering morphology. CNC yields were determined for all three CP variants. The CP-SFH-NaOH sample had the maximum CNC yield of 52.12%. Phytomelanin with admixture of lignin was recovered from alkaline extracts (8.56%) and fully characterized. Overall, the findings demonstrate the potential of integrated SFH utilization to produce high-quality cellulose derivatives and phytomelanin with admixture of lignin. Full article

Pitaya is a tropical fruit widely recognized for its intense coloration and abundance of bioactive compounds and natural pigments, associated with antioxidant properties and potential functional applications. However, its high moisture content and structural fragility make it highly susceptible to post-harvest deterioration and limit its shelf life, highlighting the need for effective preservation strategies to enable its industrial utilization. This study evaluated the production of spray-dried red pitaya (Hylocereus costaricensis) powder using the whole-fruit (pulp, peel, and seeds), since studies addressing entire fruit utilization remain scarce. The effects of air temperature (T), air flow rate (AF), maltodextrin concentration (M), and feed flow rate (FF) on moisture content, water activity, drying yield, bioactive compounds (total phenolic, flavonoid, ascorbic acid, and betalains), and color parameters were investigated. Spray drying successfully produced pitaya powders characterized by reduced moisture levels and water activity, satisfactory drying yield, and preserved bioactive compounds contents under selected processing conditions. The optimized spray drying conditions (T = 132.7 °C, AF = 1.51 m³/min; M = 9%, and FF = 0.55 L/h) were identified through the desirability function approach, indicating a balanced performance between drying efficiency and compound retention. Color parameters (L*, a*, b*, C*, H°, and ΔE) showed changes related to the operational conditions analyzed when compared with the fresh fruit. These findings support the valorization of the pitaya whole fruit and its use as a source of natural bioactive compounds for food applications. Full article

Reductive catalytic fractionation (RCF) has emerged as a representative lignin-first biorefining strategy for converting native lignin into aromatic monomers while preserving a carbohydrate-rich pulp for subsequent valorization. Although previous reviews have summarized the effects of feedstocks, solvents, and catalysts on monomer production, a process-oriented synthesis that connects reaction chemistry with reactor configuration, solvent recycling, catalyst recovery, and scale-up remains limited. This review, therefore, reassesses recent advances in RCF from an integrated process perspective. The comparative analysis indicates that monomer yield cannot be predicted by lignin content alone but is governed by the combined effects of β-O-4 abundance, lignin condensation, S/G ratio, lignin-carbohydrate connectivity, tissue structure, and solvent accessibility. Solvent systems are further evaluated not only by their ability to promote lignin extraction and intermediate stabilization, but also by their influence on carbohydrate retention, solvent recovery, and process sustainability. Catalyst development is discussed in relation to metal–support interactions, hydrogen-transfer pathways, catalyst placement, deactivation resistance, and compatibility with recycled solvents. Particular emphasis is placed on the transition from batch screening to semi-continuous, flow-through, and continuous-flow RCF, where spatial separation of lignin extraction and catalytic stabilization can improve residence-time control, mass transfer, catalyst recovery, and process scalability. The analysis further indicates that high-pressure batch reactors remain useful for laboratory screening, but their direct industrial implementation is restricted by equipment cost, safety requirements, energy input, high solvent-to-biomass ratios, and solvent recovery burden. Flow-through and continuous-flow configurations, coupled with solvent-loop optimization and catalyst recovery, are, therefore, more promising for scalable RCF. Finally, techno-economic analysis, life-cycle assessment, solvent-loop design, lignin-oil upgrading, and standardized reporting requirements are discussed as essential criteria for industrial implementation. Overall, this review highlights that scalable RCF should not be regarded simply as an optimized depolymerization reaction, but as a reactor- and recycle-aware lignin-first process architecture that integrates feedstock selection, solvent-catalyst chemistry, separation strategy, catalyst lifetime, solvent recovery, and downstream utilization. Full article

The high-value utilization of non-wood pulping black liquor is of great significance for the sustainable development of the pulp and paper industry. In this study, concentrated black liquor, obtained from the five-time recycling of KOH-pretreated wheat straw chemi-thermomechanical pulp (CTMP), was used as the feedstock for the preparation of humic-like acids (HLAs) through hydrothermal humification by utilizing the enriched organic components and residual alkalinity. Urea was further introduced to synthesize nitrogen-enriched humic-like acids (N-HLAs). The hydrothermal conditions and urea dosage were systematically optimized, and the products were characterized by elemental analysis (EA), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and particle size analysis (PSA). The results showed that the optimal hydrothermal condition was 180 °C for 4 h, under which the HLA yield reached 15.75%. With the addition of 1 mol/L urea, the yield of 1N-HLA further increased to 16.81%. Structural analyses demonstrated that hydrothermal treatment promoted the transformation of small molecular organics into highly aromatic and condensed macromolecular structures, while nitrogen-containing functional groups were successfully incorporated into the HLA molecular framework through urea modification. Bioactivity assay results showed that 1N-HLA exhibited a promoting effect on radish seed germination and seedling growth at a concentration of 100 mg/L. This study provides theoretical and technical support for the valorization of pulping black liquor and the green synthesis of functional humic-like materials. Full article

The agrifood industry generates substantial amounts of waste to meet the increasing global food demand, raising environmental concerns. Valorization of these residues through the recovery of high-added-value compounds and renewable energy production, such as biogas via Anaerobic Digestion (AD), offers a sustainable solution. In this study, the potential of Olive Pomace (OP), Brewers’ Spent Grain (BSG), and Cereal Wheat Bran (BR) as substrates for AD was investigated. Lignin was removed from these biomasses using an Ionic Liquid (IL) composed of triethylamine and sulphuric acid ([Et₃N][HSO₄]), and the delignified residues, called Olive Pomace Pulp (OPP), Brewers’ Spent Grain Pulp (BSGP), and Cereal Wheat Bran Pulp (BRP), were evaluated for their biogas and biomethane production potential through the volumetric method, coupled with an alkaline trap for biogas upgrading. An analysis was performed, considering biogas and biomethane yields, AD duration, and energy requirements. Raw biomasses provided different biomethane concentrations, with OP reaching 53.73%, BSG 76.59%, and BR 77.36%. After IL treatment, the methane content was 55.6% for OPP, 60.0% for BSGP, and 54.6% for BRP. Owing to their similar composition, BSG and BR displayed comparable biomethane production profiles. The analysis highlighted BSG and BR as the most efficient substrates for AD following lignin removal. Overall, this approach demonstrates the potential of agro-industrial waste valorization to produce bioenergy and support the transition toward a circular economy. Full article

The yield of apple trees as a function of potassium fertilization and the critical levels (CLs) and sufficiency ranges (SRs) of K in the soil, leaves, and fruits were determined in two experiments (two orchards) in four crop seasons. Plants of “Royal Gala” and “Fuji Suprema” cultivars were treated with 0, 50, 100, 150, or 200 kg K₂O ha⁻¹ year⁻¹. Potassium was applied annually during the bud swelling phase and onto the soil surface in the projection of the plant canopy, without incorporation. Critical levels and SR were estimated by Bayesian segmented quantile regression models. The cultivar factor was the main source of variation in fruit yield, K concentration in leaves and pulp, and K exported by apples. The crop season was the second factor with the greatest contribution to apple yield and K concentrations in leaves. When data from all crop seasons and orchards were pooled, yield did not vary by K treatments. The concentration of K in the leaf and fruit pulp also did not change as a function of the K dose with grouped data. For fruit production, the CL of K in the soil was 170 mg dm⁻³ for both cultivars; 17.8 g kg⁻¹ and 15.8 g kg⁻¹ in leaf for “Fuji Suprema” and “Royal Gala”, respectively; 1150 mg kg⁻¹ and 1080 mg kg⁻¹ in fruit pulp for “Fuji Suprema” and “Royal Gala”, respectively. The lack of response to K fertilization indicates that the trees were operating within a nutritional plateau. Consequently, we recommend that K fertilization in subtropical apple orchards be guided strictly by soil and plant analysis. For orchards exceeding the soil critical level of 170 mg dm⁻³ and leaf concentrations of 17.8 g kg⁻¹ and 15.8 g kg⁻¹ in leaf for “Fuji Suprema” and “Royal Gala”, respectively, and 1150 mg kg⁻¹ and 1080 mg kg⁻¹ in fruit pulp for “Fuji Suprema” and “Royal Gala”, respectively, K applications may be reduced or temporarily withheld under similar high-K soil conditions, provided that soil and plant nutritional status are regularly monitored. This management strategy ensures high yields and more efficient and sustainable nutrient management. Full article