Browsing by Author "Reis, Celso A."
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- Chitosan-olive oil microparticles for phenylethyl isothiocyanate deliveryPublication . Coscueta, Ezequiel R.; Reis, Celso A.; Pintado, ManuelaPhenylethyl isothiocyanate (PEITC) is released from the enzymatic hydrolysis of gluconasturtiin, the most abundant glucosinolate found in watercress (a vegetable from the family Brassicaceae) by the enzyme myrosinase. Among all the isothiocyanates, PEITC is one of the most extensively studied with various biological activities such as antimicrobial, antioxidant and anti-inflammatory. Several studies suggested that PEITC exhibits cancer preventive and therapeutic effects on multiple types of cancers and is one of the isothiocyanates that is being tested in clinical trials. PEITC is highly reactive due to its considerably electrophilic nature. Furthermore, it is hydrophobic and has low stability, bioavailability and bioaccessibility, restricting its use in biomedical and nutraceutical or food applications. Thus, the encapsulation of this agent has the function of overcoming these limitations, promoting its solubility in water, and stabilizing it, preserving its bioactivity. So, polymeric microparticles were developed using chitosan-olive oil-PEITC systems. For this, an optimisation process (factors: olive oil: chitosan ratio and PEITC: chitosan ratio) were implemented through a 3-level (32) factorial experimental design. The responses were: the particle size, zeta-potential, polydisperse index, and entrapment efficiency. The optimal formulation was further characterized by FTIR and biocompatibility in Caco-2 cells. Optimal conditions were olive oil: chitosan and PEITC: chitosan ratios of 1.46 and 0.25, respectively. These microparticles had a size of 629 nm, a zeta-potential of 32.3 mV, a polydispersity index of 0.329, and an entrapment efficiency of 98.49%. We found that the inclusion process affected the optical behaviour of the PEITC, as well as the microparticles themselves and their interaction with the medium. Furthermore, the microparticles did not show cytotoxicity within the therapeutic values of PEITC. Thus, PEITC was microencapsulated with characteristics suitable for potential biomedical, nutraceutical and food applications.
- Chitosan-olive oil microparticles for phenylethyl isothiocyanate delivery: optimal formulationPublication . Coscueta, Ezequiel R.; Sousa, Ana Sofia; Reis, Celso A.; Pintado, ManuelaPhenylethyl isothiocyanate (PEITC), a chemopreventive compound, is highly reactive due to its considerably electrophilic nature. Furthermore, it is hydrophobic and has low stability, bioavailability and bioaccessibility. This restricts its use in biomedical and nutraceutical or food applications. Thus, the encapsulation of this agent has the function of overcoming these limitations, promoting its solubility in water, and stabilizing it, preserving its bioactivity. So, polymeric microparticles were developed using chitosan-olive oil-PEITC systems. For this, an optimisation process (factors: olive oil: chitosan ratio and PEITC: chitosan ratio) was implemented through a 3-level factorial experimental design. The responses were: the particle size, zeta-potential, polydisperse index, and entrapment efficiency. The optimal formulation was further characterised by FTIR and biocompatibility in Caco-2 cells. Optimal conditions were olive oil: chitosan and PEITC: chitosan ratios of 1.46 and 0.25, respectively. These microparticles had a size of 629 nm, a zeta-potential of 32.3 mV, a polydispersity index of 0.329, and entrapment efficiency of 98.49%. We found that the inclusion process affected the optical behaviour of the PEITC, as well as the microparticles themselves and their interaction with the medium. Furthermore, the microparticles did not show cytotoxicity within the therapeutic values of PEITC. Thus, PEITC was microencapsulated with characteristics suitable for potential biomedical, nutraceutical and food applications.
- Effects of microencapsulated phenethyl isothiocyanate on gastrointestinal cancer cells and pathogenic bacteriaPublication . Abrantes, Rafaela; Ramos, Cátia C.; Coscueta, Ezequiel R.; Costa, João; Gomes, Joana; Gomes, Catarina; Reis, Celso A.; Pintado, Maria ManuelaGastrointestinal cancers remain a global health burden, demanding more effective prevention and treatments. Phenethyl isothiocyanate (PEITC), a compound derived from cruciferous vegetables, stands out as a promising nutraceutical agent due to its chemopreventive and therapeutic properties. However, its therapeutic translation remains limited mainly due to its poor water solubility and rapid metabolism. Herein, we encapsulated PEITC into biocompatible chitosan-based microparticles with an extra virgin olive oil core to improve its bioavailability and stability. Pure PEITC's biocompatibility and microencapsulated PEITC's stability and antibacterial activity were evaluated. The antibacterial activity analysis showed microencapsulated PEITC as a promising antibacterial agent against gastrointestinal pathogenic bacteria (two Gram-positive and two Gram-negative). The impact of both pure and microencapsulated PEITC was assessed on gastrointestinal cancer cells (MKN45 gastric cancer and SW48 colon cancer cell lines). PEITC exhibited threshold or hormetic dose-dependent toxicity in colon fibroblasts and decreased gastric cancer cells' migration capacity, enhanced upon encapsulation into microparticles. In addition, microencapsulated PEITC induced downregulation of phosphorylated AKT, FAK, and ERK1/2 proteins, disrupting motility signaling pathways and tubulin expression. These findings suggest that the delivery of PEITC via chitosan-based microparticles holds promise as a nutraceutical delivery strategy against gastrointestinal disorders that predispose to cancer.
- Microbots for colonic delivery of PEITC: using INFOGEST to optimize formulation and bioaccessibilityPublication . Sousa, Ana Sofia; Coscueta, Ezequiel R.; Reis, Celso A.; Pintado, ManuelaGlobally, gastrointestinal diseases impact 40% of the population and burden healthcare services. Inflammatory bowel disease (IBD) is a common disorder affecting over 6 million people worldwide, leading to significant morbidity and mortality. Therefore, novel approaches are needed to control colonic diseases effectively with minimal side effects.Using natural bioactive compounds such as isothiocyanates (ITCs) from cruciferous vegetables has shown promise in treating various diseases. Phenethyl isothiocyanate (PEITC), an ITC found in watercress, has potential bioactivities such as antioxidant, anti-inflammatory, and anticancer effects. Hence, PEITC shows potential as a natural therapeutic strategy for IBD due to its ability to alleviate inflammation and inhibit the growth of harmful intestinal bacteria without harming healthy gut microorganisms. However, further research is necessary to establish PEITC's therapeutic potential for IBD and its impact on gut microbiota and overall intestinal health.Encapsulation technology, crucial for enhancing PEITC's effectiveness and bioavailability in food or nutraceutical matrices, offers promising therapeutic and preventive applications in IBD treatment. Colon-targeted delivery systems are highly effective, especially those activated by gut microbiota. Utilising microbiota and enzymes like β-glycosidase, these systems expressly release drugs in the colon, a strategy ideal for PEITC delivery given its poor water solubility and instability. This research aims to develop a microbot for targeted PEITC delivery to the inflamed colon. It will assess the interaction with gut microbiota and the effectiveness of target functionalities, including antioxidant and anti-inflammatory properties. The delivery system will feature a biodegradable polysaccharide coating, ensuring precise colon targeting. The INFOGEST protocol will simulate human gastrointestinal digestion in vitro, optimising the microbot's formulation and evaluating PEITC bioaccessibility. This preliminary stage will guide the enhancement of microbot design for subsequent in vivo testing.Thus, developing microbots for oral administration will provide practical solutions for preventing and controlling gastrointestinal diseases, particularly IBD, with minimal impact on the patient's quality of life.
- Microbots for colonic delivery of phenethyl isothiocyanate (PEITC): using INFOGEST to optimize formulation and bioaccessibilityPublication . Sousa, Ana Sofia; Coscueta, Ezequiel R.; Reis, Celso A.; Pintado, Manuela
- Microwave hydrodiffusion and gravity: a green extraction technology for phenylethyl isothiocyanate from watercress by-productsPublication . Sousa, Ana Sofia; Sousa, Sérgio; Silva, Inês V.; Reis, Celso A.; Coscueta, Ezequiel R.; Pintado, Maria ManuelaWatercress is a cruciferous vegetable and the primary natural source of phenylethyl isothiocyanate (PEITC), a powerful health-promoting agent. Conventional extraction of PEITC relies on harmful solvents, which limits sustainability. This study introduces a novel, solvent-free method—microwave hydrodiffusion and gravity (MHG)—to extract PEITC from watercress by-products (WCBP). Results showed that freezing WCBP is fundamental for effective PEITC extraction via MHG. Using a three-level factorial experimental design, optimal MHG extraction conditions were determined (microwave power: 1.91 W g -1 ; extraction time: 29 min), yielding a PEITC content of 1818.26 μg g -1 WCBP (dry basis), along with extracts rich in polyphenols and possessing antioxidant properties. This work demonstrates that MHG is a sustainable method for extracting isothiocyanates, supporting a zero-waste approach since the clean residue from the extraction process can be reused to obtain new ingredients, thus enhancing resource efficiency and promoting a circular economy in the agro-food industry.
- Multifunctional microencapsulation of phenethyl isothiocyanate targeting colon inflammationPublication . Sousa, Ana Sofia; Coscueta, Ezequiel R.; Reis, Celso A.; Pintado, Manuela
- Phenylethyl isothiocyanate extracted from watercress by-products with aqueous micellar systems: development and optimisationPublication . Coscueta, Ezequiel R.; Reis, Celso A.; Pintado, ManuelaPhenylethyl isothiocyanate (PEITC) was reported as a useful antioxidant, anti-inflammatory, and chemopreventive agent. Due to technological and stability issues, it is necessary to be able to extract PEITC from its natural matrix (watercress) through sustainable and scalable methodologies. In this article, we explored, for the first time, the extractive capacity of aqueous micellar systems (AMSs) of two non-ionic surfactants. For this, we compared the AMSs with conventional organic solvents. Furthermore, we developed and optimised a new integral PEITC production and extraction process by a multifactorial experimental design. Finally, we analysed the antioxidant capacity by the oxygen radical absorbance capacity (ORAC) and ABTS methods. As results, the AMSs were able to extract PEITC at the same level as the tested conventional solvents. In addition, we optimised by response surface methodology the integrated process (2.0% m/m, 25.0 C, pH 9.0), which was equally efective (ca. 2900 g PEITC/g watercress), regardless of the surfactant used. The optimal extracts showed greater antioxidant capacity than pure PEITC, due to other antioxidant compounds extracte in the process. In conclusion, by the present work, we developed an innovative cost-effective and low environmental impact process for obtaining PEITC extracts from watercress by-products.
- Phenylethyl isothiocyanate: a bioactive agent for gastrointestinal healthPublication . Coscueta, Ezequiel R.; Sousa, Ana Sofia; Reis, Celso A.; Pintado, Maria ManuelaThe incidence of gastrointestinal pathologies (cancer in particular) has increased progressively, with considerable morbidity and mortality, and a high economic impact on the healthcare system. The dietary intake of natural phytochemicals with certain bioactive properties has shown therapeutic and preventive effects on these pathologies. This includes the cruciferous vegetable derivative phenylethyl isothiocyanate (PEITC), a bioactive compound present in some vegetables, such as watercress. Notably, PEITC has antioxidant, anti-inflammatory, bactericidal, and anticarcinogenic properties. This review summarized the current knowledge on the role of PEITC as a potential natural nutraceutical or an adjuvant against oxidative/inflammatory-related disorders in the gastrointestinal tract. We also discussed the safe and recommended dose of PEITC. In addition, we established a framework to guide the research and development of sustainable methodologies for obtaining and stabilizing this natural molecule for industrial use. With PEITC, there is great potential to develop a viable strategy for preventing cancer and other associated diseases of the gastrointestinal tract. However, this topic still needs more scientific studies to help develop new PEITC products for the nutraceutical, pharmaceutical, or food industries.
- A solvent-free approach to extract phenylethyl isothiocyanate from nasturtium officinalPublication . Sousa, Ana Sofia; Coscueta, Ezequiel R.; Reis, Celso A.; Pintado, ManuelaThis research aims to utilize MHG technology to produce extracts enriched with PEITC from watercress by-products and assess their antioxidant activity and total phenolic content.