Biotransformation-Driven Enhancement of Tannins and Bioactivity in Opuntia ficus-indica Peel via Solid-State Fermentation

Optimized Extraction and Bioactivity Profiling of Phenolics from Bostrychia scorpioides (Hudson) Mont: A Sustainable Approach for Pharmaceuticals Applications

Sustainable Extraction of Tagetes erecta L.: Comparative Metabolomics and Antifungal Activity against Grapevine Pathogens

The spread of fungicide-resistant pathogens has increased interest in plant-based antifungal agents for agricultural applications. We compared subcritical CO2 extraction (SbFE), ultrasound-assisted extraction (UAE), hot reflux extraction (HRE), and Soxhlet extraction (SE) to determine their effects on the metabolite composition of Tagetes erecta L. and antifungal efficacy against Botrytis cinerea. GC–MS and UHPLC–QTOF–MS analyses, combined with chemometric methods, revealed method-specific metabolite profiles. SbFE selectively enriched thiophene derivatives and sesquiterpenes, while UAE yielded the broadest range of phenolic acids, flavonoids, and terpenoids. HRE recovered thermostable terpenes, whereas SE concentrated phenolic compounds and sterols but lacked thiophenes due to thermal degradation. Despite these chemical differences, both SbFE and SE preparations produced complete inhibition of B. cinerea under the applied test conditions (30.0 mm inhibition zones), apparently through distinct mechanisms: phototoxic thiophene-terpenoid activity versus phenolic-sterol membrane disruption. Principal component analysis confirmed clear separation between extraction methods. These results demonstrate that extraction technique must be selected according to target compound classes and intended antifungal mechanisms: SbFE for phototoxic applications, SE for contact biocides, and UAE for broad-spectrum screening.

Enhancing the extraction of phenolic compounds from biofortified apple peel by-products: ultrasound-assisted recovery, bioaccessibility, and in vitro bioactivity.

This study modeled and optimized ultrasound-assisted extraction (UAE) of phenolic compounds from 'Granny Smith' apple peel (RM) and biofortified peel subjected to controlled abiotic stresses (RM-E). A Box-Behnken design evaluated the effects of extraction ratio, ethanol concentration, and ultrasound power on total phenolic compounds (TPC), while extraction kinetics were described using the Peleg model. Optimal conditions were 1:36 w/v, 76% ethanol, and 52% ultrasound power, yielding extracts with 20-23 g kg-1 TPC and a profile dominated by flavonols and flavan-3-ols. After simulated gastrointestinal digestion, the biofortified UAE extract (USRM-E) showed 39.8% TPC bioaccessibility. Its intestinal fraction exhibited antiproliferative effects against HT-29 and Caco-2 colorectal cancer cells and showed antioxidant, anti-inflammatory, and anti-adipogenic responses in vitro. Overall, combining abiotic stress-induced biofortification with UAE improved phenolic recovery and bioaccessibility, supporting apple peel by-products as sustainable sources of bioactive ingredients for functional food applications through green extraction technologies and valorization strategies.

Biotransformation of phenolic compounds in Saccharina japonica by Monascus purpureus fermentation: Impact on composition, antioxidant profile, and in vitro bioaccessibility.

Phenolic compounds of Saccharina japonica (SJ) have low bioaccessibility due to macromolecule-bound forms. This study demonstrated that fermenting SJ with Monascus purpureus enhanced the phenolic bioaccessibility by converting bound macromolecular forms into free, low-molecular-weight forms. Fermentation increased both free and bound phenolics by 43% and 263%, respectively, with a corresponding increase in antioxidant activities. UHPLC-Q-Exactive Orbitrap-MS/MS detailed microbial biotransformation mechanisms, where complex phlorotannins and phenolic acids converted to salicylic acid, protocatechuic acid, caffeic acid, together with enrichment of luteolin, which was further transformed into low-molecular-weight phenolics during digestion. Fermentation improved digestive stability; intestinal-phase bioaccessibility relative to the corresponding undigested samples reached 134.5% (free) and 90.1% (bound), with absolute accessible phenolics approximately 1.6-fold those of digested unfermented controls. Thus, fermentation offers an effective strategy to convert inaccessible bound phenolics into bioactive, bioaccessible molecules, providing a new way to enhance the nutritional and functional value of SJ-based products.

Enhanced polyphenolic production in tissue culture-derived Opuntia ficus-indica increases larvicidal activity against Spodoptera exigua: biochemical, histological and molecular docking evidence

The accelerating resistance of Spodoptera exigua to synthetic insecticides demands the development of eco-friendly botanical alternatives. Plant tissue culture provides a controlled means to enhance the biosynthesis of defense metabolites. This study explored how in vitro micropropagation can enhance the polyphenolic profile and insecticidal efficacy of Opuntia ficus-indica cladode ethanolic extracts. These extracts, cultured on Murashige and Skoog medium without (Op1) or with plant growth regulators (Op2), were compared with greenhouse-grown (Op3) extracts for activity against second- and fourth-instar S. exigua larvae. Phytochemical analyses revealed differences among the extracts. The Op2 extract exhibited the highest total phenolic content (61.1 mg GAE g−1) and flavonoid content (131.95 mg QE g−1). HPLC profiling revealed that Op2 had higher levels of gallic acid (26.94 µg mg−1) and kaempferol (17.26 µg mg−1), whereas the greenhouse-grown extract was dominated by catechin and gallic acid. Bioassays showed that Op2 was the most toxic, with LC50 values of 4.87 and 2.70 mg mL−1 for the second and fourth instars, respectively. Biochemical assays revealed metabolic disruption, indicated by a significant elevation in lactate dehydrogenase (LDH) activity (up to 5.20-fold) and a suppression of glutathione peroxidase (GPx) activity (up to 82.18%). Histopathological examination confirmed severe damage to the integument and midgut tissues. Molecular docking analysis indicated that kaempferol exhibited the highest binding affinity for LDH and GPx (− 6.32 and − 6.72 kcal mol−1, respectively), while ferulic acid showed strong binding (− 6.12 and − 6.15 kcal mol−1, respectively). These findings identify tissue culture-enhanced O. ficus-indica as a promising biopesticide for pest management.

Valorization of Schizophyllum commune mycelia through green extraction and hydrolysate preparation: Proteomics-informed antioxidant potential and Caco-2 cell-based assessment

Schizophyllum commune mycelia obtained from submerged fermentation were investigated as a sustainable source of bioactive ingredients using an integrated workflow involving green extraction, proteomics, in silico peptide-motif prediction, and Caco-2 cellular assays. Hot-water extraction (HWE) and ultrasound-assisted extraction (UAE) were compared at different biomass loads and extraction times. Protein solubilization increased strongly with biomass load regardless of extraction method, whereas polysaccharide recovery depended mainly on extraction time. In crude extracts, UAE gave higher phenolic content than HWE. Shotgun proteomics identified 312 high-confidence proteins, from which selected proteins were used as candidate precursor sequences for antioxidant-peptide motif prediction. The hydrolysate, which contained peptides together with polysaccharides and phenolic compounds, maintained >90% Caco-2 viability and significantly reduced H2O2-induced intracellular reactive oxygen species in a dose-dependent manner. These findings provide preliminary support for the further development of the hydrolysate as a multicomponent antioxidant ingredient for functional food applications.