Consumers associate the color of food with its freshness and quality. More and more attention is being paid to natural colorants that bring additional health benefits to humans. Such natural substances are the carotenoids (yellow to orange), the anthocyanins (red to blue), and the betalains (red and yellow), which are very sensitive to exposure to light, air, high temperatures, and chemicals. Stability and diversity in terms of color can be optimized by using environmentally friendly and selective extraction processes that provide a balance between efficacy, safety, and stability of the resulting extracts. Green solvents like water, supercritical fluids, natural deep eutectic solvents, and ionic liquids are the most proper green solvents when combined with different extraction techniques like maceration, supercritical extraction, and ultrasound-assisted or microwave-assisted extraction. The choice of the right extracting agent is crucial for the selectivity of the extraction method and the stability of the prepared colorant. The present work reviews the green solvents used for the extraction of natural food colorants from plants and focuses on the issues related to the selectivity and stability of the products extracted.

Vitamin K₃ (menadione), classified as a pro-vitamin, is a synthetic form of the fat-soluble family of vitamin K compounds. The combination of the vitamin with other molecules sharing structural and/or functional similarities, such as naturally occurring polyphenols, vitamins, or biopolymers, could potentiate mutual improvement of their antioxidant activity. The aim of the present study was to evaluate the role and contribution of vitamin K₃ to the in vitro radical scavenging capacity of double and triple combinations with the phytochemicals naringenin and lignin, as well as assess possible intermolecular interactions between the bioactive compounds. Comparative analyses of the DPPH and ABTS radical scavenging activity of the pure substances vitamin K₃, naringenin, and lignin; the two-component systems lignin/vitamin K₃ and vitamin K₃/naringenin; and the triple combination vitamin K₃/flavonoid/lignin were carried out. The experimental results demonstrated increased DPPH and ABTS activities of the vitamin in combination with lignin compared to those of the two pure substances, i.e., a synergistic effect was observed. The registered significant increases in the radical scavenging activity of the triple combination determined via both methods are indicative of a remarkable potentiation effect, i.e., higher antioxidant potential exceeding the additive activity of the three pure substances.

Background/Objectives: Acetaminophen (paracetamol or APAP) overdose is a major cause of acute liver injury mediated by oxidative stress, inflammation, and hepatocellular necrosis. The present study investigates the in vivo hepatoprotective potential of morin (M), lignin nanoparticles (LN), and morin-encapsulated lignin nanoparticles (LMN) against APAP-induced hepatotoxicity in mice. The specific goal was to determine whether LMN could strengthen hepatic antioxidant and anti-inflammatory defenses prior to toxic insult, which aligns with a prophylactic model rather than a post-injury clinical rescue approach. This study was guided by the primary hypothesis that LMN pretreatment would markedly reduce APAP-induced hepatic injury. Methods: Experimental groups included control, APAP, M, LN, LMN, M+APAP, LN+APAP, and LMN+APAP treatments. Serum hepatic biomarkers, oxidative stress parameters, and inflammatory cytokines were analyzed to assess protective responses. Results: APAP exposure markedly elevated aspartate aminotransferase (AST) and alkaline phosphatase (ALP) levels, indicating severe hepatic dysfunction, accompanied by increased lipid peroxidation and pro-inflammatory cytokine production. LMN+APAP treatment significantly restored hepatic enzyme levels to approximately normal values and suppressed malondialdehyde (MDA) formation, while enhancing superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities. LMN also downregulated interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and interleukin 1β (IL-1β), while upregulating interleukin 10 (IL-10), suggesting effective attenuation of inflammatory signaling. Correlation analyses demonstrated positive interactions between MDA, cytokines, and hepatic enzymes, whereas antioxidant enzyme levels were inversely correlated with liver injury markers. Histopathological analysis revealed that treatment with LMN enhanced hepatoprotection, demonstrating predominantly mild, reversible lesions and suggesting a synergistic antioxidant and immunomodulatory effect. Conclusions: It could be concluded that LMN provided superior hepatoprotection compared to M or LN. These findings establish LMN as a promising bio-based nanotherapeutic agent for mitigating drug-induced hepatotoxicity through coordinated antioxidant and anti-inflammatory mechanisms.