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Pineapple-crown papers with partial NaOH substitution: Performance, costs, and life-cycle footprints
(Elsevier BV, 2026-02)
Ginger Capa
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Cinthia González
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GALLEGOS CASTRO, ELVIA DEL CARMEN
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Patricia Alba
;
Edwin Vera
Non-wood agro-residues can reduce the environmental and cost burdens of papermaking, yet process alkalinity often drives impacts. Pineapple crowns were valorized as fiber feedstock and evaluated partial substitution of NaOH with NaHCO3 during processing, using NaOH–NaHCO3 ratios of 1:0, 3:1, and 1:1 (P100:0, P75:25, P50:50). Physical (grammage, thickness, porosity, burst, pH, water uptake) and instrumental characterizations, including Fourier-transform infrared spectroscopy (FTIR), thermogravimetric and derivative thermogravimetric analysis (TGA/DTGA), and scanning electron microscopy (SEM), were coupled with cradle-to-gate life-cycle (CF: carbon footprint; WF: water footprint) and unit-cost analyses. P75:25 achieved the highest grammage (71.86 ± 0.49 g/m2) and balanced network consolidation, while P100:0 maximized burst (19.53 ± 0.91 psi); P50:50 increased porosity and moisture uptake. TGA/DTGA indicated effective polysaccharide/lignin breakdown for P100:0 and P75:25, with elevated high-temperature residue in P50:50, aligning with SEM-resolved fiber compaction. Environmental results decreased monotonically with sodium-bicarbonate substitution: total CF = 0.25, 0.22 (−12 %), and 0.19 kg CO2-eq for P100:0, P75:25, and P50:50. WF per sheet was 6.56, 3.72, and 3.28 L for P100:0, P75:25, and P50:50, respectively. Despite lab-scale costs (≈4.0 USD/sheet), sensitivity indicates reagent price and electricity as main levers. Overall, P75:25 offers the best performance-to-impact trade-off preserving mechanical integrity while lowering CF and WF vs P100:0 supporting pineapple-crown papers as credible candidates for lightweight packaging and printing.
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Bioactive Phenolic Compounds from Rambutan - Nephelium lappaceum L. - Shell: Encapsulation, Structural Stability, and Multifunctional Activities
(MDPI AG, 2025-11-09)
Carlos Barba Ostria
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Orestes López
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Alexis Debut
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MAYORGA RAMOS, ARIANNA CAROLINA
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ZÚÑIGA MIRANDA, JOHANA JANINA
Rambutan (Nephelium lappaceum) shell, an agro-industrial by-product, is a rich source of phenolic acids and minor anthocyanins, but its direct use is limited by instability and low bioavailability. We extracted phenolic-rich fractions and produced maltodextrin microcapsules by spray drying, then confirmed chemical entrapment and amorphization by FTIR, SEM, and XRD. The formulation showed high encapsulation efficiency and high antioxidant capacity (DPPH), selective bactericidal activity against Pseudomonas aeruginosa and Burkholderia cepacia, and strong inhibition of Staphylococcus aureus and Listeria monocytogenes biofilms, while exhibiting negligible hemolysis (<2%) across tested concentrations. Antitumor effects were moderate with low selectivity in vitro, indicating that phenolic-acid-driven redox modulation may require fractionation or delivery optimization for oncology applications. Overall, spray-dried microcapsules provided structural stability and safety while concentrating multifunctional activities relevant to food and biomedical uses. By valorizing a tropical waste stream into a bioactive, hemocompatible ingredient, this work aligns with societal goals on health and sustainable production (SDG 3 and SDG 12) and offers a scalable route to deploy underutilized phenolic resources.</jats:p>
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Phytosynthesis of Silver Nanoparticles Using Mansoa alliacea (Lam.) A.H. Gentry (Bignoniaceae) Leaf Extract: Characterization and Their Biological Activities
(MDPI AG, 2024-09-25)
ZUÑIGA MIRANDA, JOHANA JANINA
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Saskya E. Carrera-Pacheco
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GONZALEZ PASTOR, REBECA EUGENIA
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MAYORGA RAMOS, ARIANNA CAROLINA
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Cristina Rodríguez-Pólit
Background. Mansoa alliacea is a native plant renowned for its medicinal properties in traditional healing in the Amazon Region. This plant is rich in polyphenols, flavonoids, anthocyanins, phenolic acids, tannins, ketones, triterpenes, as well as other bioactive compounds. Objectives. This study aims to develop an innovative, eco-friendly method for synthesizing silver nanoparticles using an aqueous extract of M. alliacea (Ma-AgNPs), enhancing the biological activities of AgNPs by leveraging the therapeutic potential of the plant’s bioactive compounds. Methods. Silver nanoparticles were synthesized using the aqueous extract of M. alliacea. The biological activities of Ma-AgNPs were assessed, including antibacterial, anti-inflammatory, antioxidant, antitumor, and anti-biofilm effects, along with evaluating their hemolytic activity. Results. Quantitative analysis revealed that Ma-AgNPs exhibit potent antibacterial activity against multidrug and non-multidrug-resistant bacteria, with MIC values ranging from 1.3 to 10.0 µg/mL. The Ma-AgNPs significantly reduced NO production by 86.9% at 4 µg/mL, indicating strong anti-inflammatory effects. They demonstrated robust antioxidant activity with an IC50 of 5.54 ± 1.48 µg/mL and minimal hemolytic activity, with no hemolysis observed up to 20 µg/mL and only 4.5% at 40 µg/mL. Their antitumor properties were notable, with IC50 values between 2.9 and 5.4 µg/mL across various cell lines, and they achieved over 50% biofilm inhibition at concentrations of 30–40 µg/mL. Conclusions. These findings underscore the potential of Ma-AgNPs for biomedical applications, particularly in developing new antimicrobial agents and bioactive coatings with reduced toxicity. This research highlights a sustainable approach that not only preserves but also amplifies the inherent biological activities of plant extracts, paving the way for innovative therapeutic solutions.
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Bioactive Properties of Microencapsulated Anthocyanins from Vaccinium floribundum and Rubus glaucus
(MDPI AG, 2024-11-21)
Carlos Barba-Ostria
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GONZALEZ PASTOR, REBECA EUGENIA
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Castillo-solís Fabián
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Saskya E. Carrera-Pacheco
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Orestes Lopez
Anthocyanins, widely recognized for their antioxidant properties and potential health benefits, are highly susceptible to degradation due to environmental factors such as light, temperature, and pH leading to reduced bioavailability and efficacy. Microencapsulation, which involves entrapment in a matrix to enhance stability and bioavailability. This study aims to investigate the bioactive properties of microencapsulated anthocyanins derived from Vaccinium floribundum (Andean blueberry) and Rubus glaucus (Andean blackberry). The extracts from V. floribundum and R. glaucus were microencapsulated using maltodextrin as the carrier agent due to its film-forming properties and effectiveness in stabilizing sensitive compounds through a spray-drying process. The microcapsules were characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) to assess their chemical and morphological properties. The biological activities of these microencapsulated anthocyanins were evaluated using in vitro assays for their antibacterial, antioxidant, and anti-inflammatory effects. The results indicated enhanced bioactivity of the microencapsulated anthocyanins, suggesting their potential use in developing functional foods and pharmaceuticals. This study provides valuable insights into the effectiveness of microencapsulation in preserving anthocyanins’ functional properties and enhancing their health-promoting effects, highlighting the potential for application in the food and pharmaceutical industries.
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Microencapsulation of Anthocyanins from Zea mays and Solanum tuberosum: Impacts on Antioxidant, Antimicrobial, and Cytotoxic Activities
(MDPI AG, 2024-11-27)
Carlos Barba-Ostria
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Yenddy Carrero
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Jéssica Guamán-Bautista
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Orestes López
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Christian Aranda
Objectives: This study investigates the biological activities of microencapsulated anthocyanins extracted from two Andean ancestral edible plants, Solanum tuberosum, and Zea mays, with a focus on their potential applications in functional foods and therapeutics. The primary objective was to evaluate their antioxidant, antimicrobial, and cytotoxic properties alongside structural and functional analyses of the microencapsulation process. Methods: Anthocyanins were extracted and microencapsulated using maltodextrin as a carrier. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed to analyze the stability and structure of the microencapsulated particles. The antioxidant, antimicrobial, and cytotoxic activities of the microencapsulated were assessed through established assays. Results:S. tuberosum exhibited superior antioxidant capacity and potent anticancer activity against HepG2 and THJ29T cell lines, while Z. mays demonstrated significant antimicrobial efficacy against multidrug-resistant bacterial strains and biofilm-forming pathogens. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) confirmed the stabilization of anthocyanins within a maltodextrin matrix, enhancing their bioavailability and application potential. Conclusions: These results highlight the versatility of microencapsulated anthocyanins as bioactive agents for industrial and therapeutic applications. Future studies should explore in vivo validation and synergistic formulations to optimize their efficacy and broaden their use in nutraceutical and pharmaceutical fields.
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Green Synthesis of Silver Oxide Nanoparticles from Mauritia flexuosa Fruit Extract: Characterization and Bioactivity Assessment
(MDPI AG, 2024-11-22)
ZUÑIGA MIRANDA, JOHANA JANINA
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David Vaca-Vega
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Karla Vizuete
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Saskya E. Carrera-Pacheco
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GONZALEZ PASTOR, REBECA EUGENIA
The increasing prevalence of multidrug-resistant (MDR) pathogens, persistent biofilms, oxidative stress, and cancerous cell proliferation poses significant challenges in healthcare and environmental settings, highlighting the urgent need for innovative and sustainable therapeutic solutions. The exploration of nanotechnology, particularly the use of green-synthesized nanoparticles, offers a promising avenue to address these complex biological challenges due to their multifunctional properties and biocompatibility. Utilizing a green synthesis approach, Mauritia flexuosa Mf-Ag2ONPs were synthesized and characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy coupled with scanning electron microscopy (EDS-SEM), UV-Vis spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The Mf-Ag2ONPs exhibited potent antibacterial effects against both non-resistant and MDR bacterial strains, with minimum inhibitory concentrations (MICs) ranging from 11.25 to 45 µg/mL. Mf-Ag2ONPs also demonstrated significant antifungal efficacy, particularly against Candida glabrata, with an MIC of 5.63 µg/mL. Moreover, the nanoparticles showed strong biofilm inhibition capabilities and substantial antioxidant properties, underscoring their potential to combat oxidative stress. Additionally, Mf-Ag2ONPs exhibited pronounced anticancer properties against various cancer cell lines, displaying low IC50 values across various cancer cell lines while maintaining minimal hemolytic activity at therapeutic concentrations. These findings suggest that Mf-Ag2ONPs synthesized via an eco-friendly approach offer a promising alternative for biomedical applications, including antimicrobial, antifungal, antioxidant, and anticancer therapies, warranting further in vivo studies to fully exploit their therapeutic potential.
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A Circular Bioeconomy Approach to Using Post-Bioadsorbent Materials Intended for the Removal of Domestic Wastewater Contaminants as Potential Reinforcements
(MDPI AG, 2024-06-27)
Cristina E. Almeida-Naranjo
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Alex Darío Aguilar
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Vladimir Valle
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Carlos Bastidas-Caldes
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Alexis Debut
Agro-industrial residue valorization under the umbrella of the circular bioeconomy (CBE) has prompted the search for further forward-thinking alternatives that encourage the mitigation of the industry’s environmental footprint. From this perspective, second-life valorization (viz., thermoplastic composites) has been explored for agro-industrial waste (viz., oil palm empty fruit bunch fibers, OPEFBFs) that has already been used previously in other circular applications (viz., the removal of domestic wastewater contaminants). Particularly, this ongoing study evaluated the performance of raw residues (R-OPEFBFs) within three different size ranges (250–425, 425–600, 600–800 µm) both before and after their utilization in biofiltration processes (as post-adsorbents, P-OPEFBFs) to reinforce a polymer matrix of acrylic resin. The research examined the changes in R-OPEFBF composition and morphology caused by microorganisms in the biofilters and their impact on the mechanical properties of the composites. Smaller R-OPEFBFs (250–425 µm) demonstrated superior mechanical performance. Additionally, the composites with P-OPEFBFs displayed significant enhancements in their mechanical properties (3.9–40.3%) compared to those with R-OPEFBFs. The combination of the three fiber sizes improved the mechanical behavior of the composites, indicating the potential for both R-OPEFBFs and P-OPEFBFs as reinforcement materials in composite applications.

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