Solid-State Fermented Pineapple Peel: A Novel Food Ingredient with Antioxidant and Anti-Inflammatory Properties.

It has been reported that pineapple (Ananas comosus) contains healthy nutrients and phytochemicals associated with antioxidant and anti-inflammatory capacities. However, a substantial amount of pineapple residue is produced due to a lack of valorization applications at the industrial scale, resulting in the loss of valuable nutrients. Solid-state fermentation (SSF) is proposed as an innovative strategy to enhance the release of bound phenolics from pineapple residues. In this work, the effects of SSF of pineapple peels with Lactobacillus plantarum, Lactobacillus rhamnosus, and Aspergillus oryzae on the release of phenolic compounds and their antioxidant and anti-inflammatory activities were evaluated, respectively. Pineapple peel extracts after SSF showed an increase in the release of phenolic compounds (248.11% with L. plantarum, 182% with A. oryzae, and 180.10% with L. rhamnosus), which led to an increase in the cellular antioxidant (81.94% with L. rhamnosus) and anti-inflammatory potential (nitric oxide inhibition of 62% with L. rhamnosus) compared to non-fermented extracts. Therefore, SSF of pineapple peels with L. plantarum, L. rhamnosus, and A. oryzae thrives as a new approach for the production of secondary metabolites with remarkable biological benefits, which can be the precursors for novel biofortified and nutraceutical-enriched foods that meet the needs of the most demanding and health-conscious consumers.

Immunomodulatory and Antioxidant Effects of Spray-Dried Encapsulated Kale Sprouts after In Vitro Gastrointestinal Digestion.

The health-related compounds present in kale are vulnerable to the digestive process or storage conditions. Encapsulation has become an alternative for their protection and takes advantage of their biological activity. In this study, 7-day-old Red Russian kale sprouts grown in the presence of selenium (Se) and sulfur (S) were spray-dried with maltodextrin to assess their capacity to protect kale sprout phytochemicals from degradation during the digestion process. Analyses were conducted on the encapsulation efficiency, particle morphology, and storage stability. Mouse macrophages (Raw 264.7) and human intestinal cells (Caco-2) were used to assess the effect of the intestinal-digested fraction of the encapsulated kale sprout extracts on the cellular antioxidant capacity, the production of nitric oxide (NOx), and the concentrations of different cytokines as indicators of the immunological response. The highest encapsulation efficiency was observed in capsules with a 50:50 proportion of the hydroalcoholic extract of kale and maltodextrin. Gastrointestinal digestion affected compounds' content in encapsulated and non-encapsulated kale sprouts. Spray-dried encapsulation reduced the phytochemicals' degradation during storage, and the kale sprouts germinated with S and Se showed less degradation of lutein (35.6%, 28.2%), glucosinolates (15.4%, 18.9%), and phenolic compounds (20.3%, 25.7%), compared to non-encapsulated ones, respectively. S-encapsulates exerted the highest cellular antioxidant activity (94.2%) and immunomodulatory activity by stimulating IL-10 production (88.9%) and COX-2 (84.1%) and NOx (92.2%) inhibition. Thus, encapsulation is an effective method to improve kale sprout phytochemicals' stability and bioactivity during storage and metabolism.

Selenium, Sulfur, and Methyl Jasmonate Treatments Improve the Accumulation of Lutein and Glucosinolates in Kale Sprouts.

Kale sprouts contain health-promoting compounds that could be increased by applying plant nutrients or exogenous phytohormones during pre-harvest. The effects of selenium (Se), sulfur (S), and methyl jasmonate (MeJA) on lutein, glucosinolate, and phenolic accumulation were assessed in kale sprouts. Red Russian and Dwarf Green kale were chamber-grown using different treatment concentrations of Se (10, 20, 40 mg/L), S (30, 60, 120 mg/L), and MeJA (25, 50, 100 µM). Sprouts were harvested every 24 h for 7 days to identify and quantify phytochemicals. The highest lutein accumulation occurred 7 days after S 120 mg/L (178%) and Se 40 mg/L (199%) treatments in Red Russian and Dwarf Green kale sprouts, respectively. MeJA treatment decreased the level of most phenolic levels, except for kaempferol and quercetin, where increases were higher than 70% for both varieties when treated with MeJA 25 µM. The most effective treatment for glucosinolate accumulation was S 120 mg/L in the Red Russian kale variety at 7 days of germination, increasing glucoraphanin (262.4%), glucoerucin (510.8%), 4-methoxy-glucobrassicin (430.7%), and glucoiberin (1150%). Results show that kales treated with Se, S, and MeJA could be used as a functional food for fresh consumption or as raw materials for different industrial applications.

Improving the Health-Benefits of Kales (Brassica oleracea L. var. acephala DC) through the Application of Controlled Abiotic Stresses: A Review.

Kale (Brassica oleracea L. var. acephala DC) is a popular cruciferous vegetable originating from Central Asia, and is well known for its abundant bioactive compounds. This review discusses the main kale phytochemicals and emphasizes molecules of nutraceutical interest, including phenolics, carotenoids, and glucosinolates. The preventive and therapeutic properties of kale against chronic and degenerative diseases are highlighted according to the most recent in vitro, in vivo, and clinical studies reported. Likewise, it is well known that the application of controlled abiotic stresses can be used as an effective tool to increase the content of phytochemicals with health-promoting properties. In this context, the effect of different abiotic stresses (saline, exogenous phytohormones, drought, temperature, and radiation) on the accumulation of secondary metabolites in kale is also presented. The information reviewed in this article can be used as a starting point to further validate through bioassays the effects of abiotically stressed kale on the prevention and treatment of chronic and degenerative diseases.

Wounding and UVB Light Synergistically Induce the Biosynthesis of Phenolic Compounds and Ascorbic Acid in Red Prickly Pears (Opuntia ficus-indica cv. Rojo Vigor).

The present study evaluated the effects of ultraviolet B (UVB) radiation and wounding stress, applied alone or combined, on the biosynthesis of phenolic compounds and ascorbic acid in the peel and pulp of red prickly pear (Opuntia ficus-indica cv. Rojo Vigor). Whole and wounded-fruit samples were treated with UVB radiation (6.4 W·m-2) for 0 and 15 min, and stored for 24 h at 16 °C. Phytochemical analyses were performed separately in the peel and pulp. The highest phenolic accumulation occurred after storage of the whole tissue treated with UVB, where the main phenolic compounds accumulated in the peel and pulp were quercetin, sinapic acid, kaempferol, rosmarinic acid, and sinapoyl malate, showing increases of 709.8%, 570.2%, 442.8%, 439.9%, and 186.2%, respectively, as compared with the control before storage. Phenylalanine ammonia-lyase (PAL) activity was increased after storage of the whole and wounded tissue treated with UVB light, and this increase in PAL activity was associated to phenolic accumulation. On the other hand, l-galactono-γ-lactone dehydrogenase (GalLDH) activity and ascorbic acid biosynthesis was enhanced due to UVB radiation, and the effect was increased when UVB was applied in the wounded tissue showing 125.1% and 94.1% higher vitamin C content after storage when compared with the control. Respiration rate was increased due to wounding stress, whereas ethylene production was increased by wounding and UVB radiation in prickly pears. Results allowed the generation of a physiological model explaining the UVB and wound-induced accumulation of phenolic compounds and ascorbic acid in prickly pears, where wounding facilitates UVB to access the underlying tissue and enhances an apparent synergistic response.

Using a Functional Carrot Powder Ingredient to Produce Sausages with High Levels of Nutraceuticals.

In this study, a functional carrot powder (FCP) ingredient was obtained by applying wounding stress to carrot (shredding and storing for 48 hr at 15 °C) prior to dehydration (60 °C) and milling. Likewise, FCP was incorporated into sausage formulations, which were further characterized. The application of wounding stress in carrots resulted in a FCP with higher fiber (30.1%) and chlorogenic acid (798.4%) content as compared with control carrot powder (CCP). Likewise, FCP showed higher water (19%) and oil (3.9%) absorption capacity as compared with CCP. Sausage formulation with 4% (w/w) of FCP was characterized, further evaluated during storage (42 days, 4 °C), and compared with a formulation added with 4% (w/w) CCP. FCP and CCP formulations increased fiber of sausages by 72.7%, and fortified them with carotenoids, providing 30% to 40% of vitamin A daily requirements per portion (62.5 g). FCP did not affect purge loss, and sausages contained 270% and 377% more total phenolics and chlorogenic acid content as compared with CCP sausages. FCP formulation presented adequate sensory acceptability and its carotenoid and phenolic content remained stable during storage. Results indicated that FCP could be used as an ingredient in sausage formulation to increase the content of nutraceuticals without affecting its shelf-life. PRACTICAL APPLICATION: Wounding stress (by shredding) was applied to carrots prior to dehydration and milling to obtain a carrot powder with higher fiber and phenolic compounds as compared with control carrot powder (CCP). FCP showed higher water and oil absorption capacity than CCP. FCP addition to sausage formulations at 4% didn't affect purge loss, and resulted in sausages with higher phenolic compounds and dietary fiber. Furthermore, FCP formulations presented adequate sensory acceptability and its carotenoid and phenolic content remained stable during storage. FCP could be used as an ingredient in sausage formulation to increase the content of nutraceuticals without affecting its shelf-life.