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Pineapple-crown papers with partial NaOH substitution: Performance, costs, and life-cycle footprints
(Elsevier BV, 2026-02)
Ginger Capa
;
Cinthia González
;
GALLEGOS CASTRO, ELVIA DEL CARMEN
;
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 Compounds, Antioxidant, and Antimicrobial Activity of Seeds and Mucilage of Non-Traditional Cocoas
(MDPI AG, 2025-02-28)
Elena Coyago Cruz
;
Iván Salazar
;
Aida Guachamin
;
Melany Alomoto
;
Marco Cerna
The biodiversity of the Amazon rainforest includes little-known cocoa species, which are essential resources for local communities. This study evaluated the bioactive compounds and antioxidant and antimicrobial activity of seeds and mucilage of four non-traditional cocoa species (Theobroma subincanum, T. speciosum, T. bicolor and Herrania nitida). Physico-chemical properties, minerals, vitamin C, organic acids, phenolics, and carotenoids were analysed by spectrophotometric and chromatographic techniques. The antioxidant activity was measured by ABTS and DPPH, along with the antimicrobial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus mutans, as well as Candida albicans and Candida tropicalis. T. subincanum seeds scored high in titratable acidity, magnesium, sodium, syringic acid, chlorogenic acid, caffeic acid, rutin, and quercetin. In contrast, the mucilage scored high in calcium, m-coumaric acid, ferulic acid, kaempferol, quercetin glycoside, and antimicrobial activity against Streptococcus mutans. T. speciosum mucilage excelled in malic acid, tartaric acid, naringenin, and antioxidant capacity. T. bicolor seeds excelled in lutein and antimicrobial activity against Staphylococcus aureus and Candida albicans, and mucilage in iron, potassium, vitamin C, citric acid, gallic acid and 4-hydroxybenzoic acid, zeaxanthin, β-carotene, and antioxidant capacity by ABTS. The mucilage of H. nitida has a high soluble solids content. These results highlight the potential of these species as sustainable sources of functional compounds and nutraceuticals.
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Functional, Antioxidant, Antibacterial, and Antifungal Activity of Edible Flowers
(MDPI AG, 2024-10-25)
Elena Coyago-Cruz
;
Alejandro Alarcón
;
Aida Guachamin
;
Gabriela Méndez
;
Edison Osorio
Edible flowers have been used since ancient times, but their potential for improving human health has not been explored. This study aimed to evaluate the profile of bioactive compounds (organic acids, phenolics, and carotenoids) and the antioxidant and antimicrobial activity of nine flower varieties with high concentrations of carotenoids or total phenolic compounds. Ninety-three edible flowers were analysed for physicochemical characteristics, total phenolic and carotenoid concentrations, and antioxidant activity (ABTS). Bioactive profiles were determined by rapid resolution liquid chromatography (RRLC), and antimicrobial activity was determined against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus mutans, and Candida albicans and Candida tropicalis. Chrysanthemum x hybrid orange, Helianthus annuus yellow, Tagetes patula orange, Canna indica red, and Hibiscus rosa-sinensis (orange1 and yellow) showed significant concentrations of total carotenoids. In contrast, Pelargonium hortorum orange2, Hibiscus rosa-sinensis red1, and Rosa x hybrid variety medium yellow showed high levels of total phenolics. The predominant compounds in these species were citric acid (991.4 mg/g DW in Hibiscus rosa-sinensis red1), 4-hydroxybenzoic acid (936.2 mg/100 g DW in P. hortorum orange2), kaempferol (971. 9 mg/100 g DW in T. patula orange), quercetin glucoside (958.8 in C. x hybrid), quercetin (919.3 mg/100 g DW in T. patula), α-carotene, and β-carotene in T. patula orange (989.5 and 601.2 mg/100 g DW, respectively). Regarding antimicrobial activity, T. patula orange and P. hortorum orange2 inhibited bacterial growth, while C. x hybrid orange and P. hortorum orange2 inhibited Candida albicans, and the latter inhibited Candida tropicalis. These results indicate the potential of edible flowers as a natural source of bioactive compounds and as a tool in the fight against antimicrobial resistance.
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Bioactive Composition of Tropical Flowers and Their Antioxidant and Antimicrobial Properties
(MDPI AG, 2024-11-24)
Elena Coyago-Cruz
;
Alejandro Barrigas
;
Aida Guachamin
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HEREDIA MOYA, JORGE HUMBERTO
;
ZUÑIGA MIRANDA, JOHANA JANINA
This study evaluated tropical flower petals’ bioactive compounds and antioxidant and antimicrobial properties. The physicochemical characteristics, carotenoids, phenolics, anthocyanins, organic acids, and antioxidant activity of 67 flowers were analyzed. In addition, the antimicrobial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus mutans, Candida albicans, and Candida tropicalis of 35 species was determined. A 2 × 3 experimental design was used for the extraction of carotenoids and phenolics, including solvents and ultrasonic agitation times. The mixture of methanol–acetone–dichloromethane (1:1:2) and acetone–methanol (2:1) resulted in the highest concentration of carotenoids, while acidified 80% methanol favoured phenolic extraction. Renealmia alpinia was extremely rich in carotenoids (292.5 mg β-carotene/g DW), Pleroma heteromallum in anthocyanins (7.35 mg C-3-gl/g DW), while a high content of citric acid was found in Hibiscus rosa-sinensis (17,819 mg/100 g DW). On the other hand, Thibaudia floribunda showed the highest antioxidant activity (7.8 mmol Trolox equivalent/g DW). The main phenolics were m-coumaric acid in Acalypha poiretii (12,044 mg/100 g DW), 4-hydroxybenzoic acid in Brugmansia arborea (10,729 mg/100 g DW), and kaempferol in Dahlia pinnata (8236 mg/100 g DW). The extract of Acalypha poiretii, Brownea macrophylla, and Cavendishia nobilis showed antibacterial activity, while the extract of Pleroma heteromallum was the only one active against Candida albicans. These findings highlight the potential health benefits from certain tropical flowers.
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Bioactive Compound Profiling and Antioxidant Activity of Phytelephas tenuicaulis and Other Amazonian Fruits
(MDPI AG, 2024-07-07)
Elena Coyago-Cruz
;
David Valenzuela
;
Aida Guachamin
;
Gabriela Méndez
;
HEREDIA MOYA, JORGE HUMBERTO
The Amazon region is home to many plant species, many of which have not been studied. The objective was to evaluate the physicochemical properties, bioactive compounds, and antioxidant activity of Phytelephas tenuicalis (tintiuk), Grias neuberthii (apai), Euterpe oleracea (acai), and Mauritia flexuosa (brown moriche). Physicochemical analyses were carried out on fresh fruit from local markets. Bioactive compounds (carotenoids, phenolics, vitamin C, and organic acids) were quantified in the freeze-dried pulp by rapid-resolution liquid chromatography (RRLC), and antioxidant activity was determined by ABTS and DPPH assays. The results showed high soluble solids (10.7 °Brix) and ascorbic acid (67.3 mg/100 g DW) in tintiuk; β-carotene (63.4 mg/100 g DW) and malic acid (19.6 g/100 g DW) in brown moriche; quercetin (944.2 mg/100 g DW) and antioxidant activity by ABTS (6.7 mmol ET/100 g DW) in apai; and citric acid (2.1 g/100 g DW) in acai. These results indicate interesting bioactive properties that could increase the consumption of these fruits nationally and internationally, benefiting local farmers and stimulating the development of new products in functional food, medicine, and cosmetics.

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