Berry fruits are an important dietary source of health-promoting antioxidant polyphenols. Interestingly, berry leaves of diverse species, including strawberries, have shown higher bioactive phytochemical content in the leaves than in the fruit. Moreover, the vegetative part of the plants is usually discarded, representing a presumably large source of underutilized bioactive biomass. In this investigation, the polyphenol profiles of tropical highland strawberry (Fragaria x ananassa cv. Festival) leaves and fruits were compared by high-performance liquid chromatography coupled with a diode array detector (UHPLC-DAD) and mass spectrometry (HPLC-MS). The total polyphenol strawberry leaf extracts exhibited a 122-fold-higher total polyphenol content and 13-fold higher antioxidant activity (ORAC) than strawberry fruits, and they showed evidence of possible photoprotective effects against UV damage in human melanoma cells (SK-MEL-28) and in murine embryo fibroblasts (NIH/3T3), together with promising anti-proliferative activities against the same melanoma cells. Seven polyphenols were confirmed by HPLC-DAD in the leaf extracts, with differences depending on fraction solubility. Moreover, three substituted quercetin derivatives, three substituted kaempferol derivatives, two anthocyanins, and catechin were confirmed in the soluble fraction by HPLC-MS. Given their higher total polyphenol content and bioactive activities, underutilized strawberry Festival leaves are a potential source of apparently abundant biomass with prospective bioactive applications.

Stevia rebaudiana, known as sweetleaf, produces a sweetener in its leaves due to the presence of steviol glycosides (stevioside and rebaudioside); however, its seed has germination problems, which is why various temporary immersion systems (TIS) have been studied for its production. The objectives of this study were to scale up the in vitro production of two S. rebaudiana cultivars using RITA®, BIT® and SETIS®, and to evaluate the production of biomass in the field. The studied cultivars were ‘Morita II’ and ‘Silvestre’. The production stages of both cultivars were: in vitro, liquid medium (with three TIS: RITA®, BIT® and SETIS®), greenhouse and finally they were taken to the field. In each TIS, five different media were evaluated, varying in each one the concentrations of sucrose, calcium pantothenate and gibberellic acid. The treatments produced vigorous plants, a greater number of leaves and shoots, and a higher multiplication rate. Both cultivars had greater stem length in BIT. Under this same system ‘Morita II’ produced eight shoots per plant, while in SETIS only three. ‘Silvestre’ had two shoots per plant with the two TIS. In both cultivars, regardless of the TIS, greenhouse survival and foliage production in the field were very similar. Therefore, the selection of the material should be based on the content of steviosides and the adaptation of the cultivar to the planting site. All TIS evaluated allowed scaling-up plant production, and both materials are promising for planting.

In the current industry, mechanized production processes are carried out, with defined parameters for these actions to be carried out by the operators. However, a deviation from these parameters is considered a human error, causing the disturbance of the production process. The article is elaborated with the purpose of identifying errors in the productive process of a Metalworking company with the joint action of the Laboratory of Ergonomics of the Technological Institute of Costa Rica. The identification of human errors was based on the Technique for human error-prediction (THERP) methodology; this analysis was complemented with a methodology of classification adapted for the administration of industrial processes called ABC methodology, 123 methodology and alfa beta range methodology to identify the critical errors for the company. Once these errors were identified, by means of an event tree the percentage was quantified by means of theoretical probabilities reported by the THERP literature and with this the percentage of affectation for the production process was analyzed. With this applied methodology, it was possible to identify in the company 26 errors in total.

Polyphenols are plant secondary metabolites that function mostly as a general stress-induced protective mechanism. Polyphenols have also gained interest due to their beneficial properties for human health. Strawberry leaves represent an agro-industrial waste material with relevant bioactive polyphenol content, which could be incorporated into circular economy strategies. However, due to the low quantities of polyphenols in plants, their production needs to be improved for cost-effective applications. The objective of this research was to compare polyphenol production in strawberry (Fragaria × ananassa cv. Festival) leaves in plants grown in greenhouse conditions and plants grown in vitro, using three possible elicitor treatments (UV irradiation, cold exposure, and cysteine). General vegetative effects were morphologically evaluated, and specific polyphenolic compounds were quantified by UHPLC-DAD-MS/MS. Gallic acid was the most abundant polyphenol found in the leaves, both in vivo and in vitro. The results showed higher amounts and faster accumulation of polyphenols in the in vitro regenerated plants, highlighting the relevance of in vitro tissue culture strategies for producing compounds such as polyphenols in this species and cultivar.

The polyphenol profiles of strawberry leaves ( Fragaria × ananassa cvs. Marisol and Festival), cultivated in the tropical highlands of Costa Rica, were analyzed using high-field (750 MHz) and benchtop (60 MHz) Nuclear Magnetic Resonance (NMR) spectroscopy. Soluble and insoluble fractions were examined, revealing differences in the aromatic (6.0–8.0 ppm) and sugar (3.0–5.5 ppm) regions. High-field NMR provided sharper, more resolved signals, allowing for the identification of glycosylated polyphenols, flavonoids, and phenolic acids. Marisol exhibited a higher diversity and intensity of glycosylated polyphenols compared to Festival. In the insoluble fractions, both cultivars showed a unique peak at 2.0 ppm, absent in the soluble fractions, likely corresponding to lipids or matrix-bound compounds. The benchtop NMR spectra, though lower in resolution, confirmed key spectral patterns and cultivar differences. This study demonstrates the complementary use of high- and low-field NMR for polyphenol profiling and highlights the potential of strawberry leaves as a valuable source of bioactive compounds, contributing to the understanding of underutilized plant materials and their applications in health-related fields.

El fruto de la fresa (Fragaria x ananassa) es un alimento ampliamente consumido a nivel mundial, y al cual se le han atribuido una amplia gama de propiedades beneficiosas para la salud humana, mayoritariamente asociadas a su potencial antioxidante. La búsqueda de fitoquímicos bioactivos en la fresa se ha enfocado en el fruto, mientras que el perfil bioquímico de las hojas ha sido poco estudiado y sigue siendo poco aprovechado, a pesar de constituir una fuente potencial de metabolitos bioactivos que podrían ser utilizados en la formulación de productos para el sector alimenticio, industrial y farmacéutico. Además, se ha reportado mayor contenido de polifenoles bioactivos en las hojas de fresa que en el fruto, y las hojas de fresa podrían ser una fuente importante de ácido elágico, un compuesto antioxidante bioactivo poco abundante en la dieta humana pero de gran potencial biomédico. Este artículo de revisión bibliográfica tiene como objetivo evaluar las características del cultivo de fresa (Fragaria x ananassa) en Costa Rica, con miras al aprovechamiento integral de los residuos agroindustriales de este cultivo. La información consultada demostró que la comercialización del cultivo de fresa se enfoca en el fruto, mientras que las hojas y el resto del material vegetativo de la planta se descartan periódicamente, y podrían ser incorporados en nuevas cadenas productivas. Este tipo de estrategias son de especial importancia para países pequeños en desarrollo y con economías de base agrícola, para mejorar el aprovechamiento de los residuos agroindustriales y darles un mayor valor agregado a los cultivos, en beneficio del ambiente y la salud humana.