ABSTRACT
A potential alternative to the use of chemical products with oomyceticidal action for the control of Phytophthora capsici in vegetables is the use of antimicrobial metabolites, biosynthesized in Bacillus species. The objective of this study was to induce the biosynthesis of lipopeptides in Bacillus amyloliquefaciens KX953161.1 by using glutamic acid, iron, cellulose, chitin, or inactive Colletotrichum spp. cells. The in vitro oomyceticidal effect of the bacterial lipopeptides on zoospores of Phytophthora capsici was evaluated. The lipopeptides identified and quantified in the crude extracts by high performance thin layer chromatography (HPTLC) were fengycin and surfactin. The bacterial culture with inactive fungal cells yielded the greatest biosynthesis of lipopeptides, at 1847.02± 11.8 and 2563.45± 18.4 µg/ml of fengycin and surfactin, respectively and the treatments that obtained lower production of these lipopeptides, were those to which iron and cellulose were added with 608.05 ± 22.6 and 903.74± 22.1; 563.31± 11.9 and 936.96± 41.1 µg/ml for fengicin and surfactin, respectively. The lipopeptide extracted showed 100% germination inhibition on zoospores of P. capsici, revealing encystment, malformations in the germ tube and cellular degradation. Lipopeptides have the potential to control P. capsici; however, the biosynthesis of these lipopeptides requires further study to determine their biological mode of action and optimize lipopeptide performance and profile.
Subject(s)
Bacillus amyloliquefaciens , Phytophthora , Bacillus amyloliquefaciens/metabolism , Cellulose , Chitin , Complex Mixtures , Glutamic Acid , Iron , Lipopeptides/chemistry , Lipopeptides/metabolism , Lipopeptides/pharmacology , Peptides, Cyclic/chemistry , Peptides, Cyclic/pharmacologyABSTRACT
Pumpkin pulp is the main waste generated by pumpkin seed growers. This agro-industrial waste is a valuable source of bioactive compounds, especially carotenoids (ß-carotene, α-carotene, and lutein), which exhibit a broad spectrum of health-promoting effects. In this study, vegetable oils (canola, corn, and soybean oil) were used as green solvent alternatives to conventional organic solvents for carotenoid extraction from dried pumpkin pulp (DPP) waste. The highest carotenoid extraction yield (CEY) was obtained with canola oil, at a 1:10 DPP/oil ratio. Response surface methodology (RSM) was used to optimize the extraction process parameters (temperature, time, and stirring rate) through a Box-Behnken design (BBD) maximizing CEY in canola oil. The extraction temperature and stirring rate were found to have a significant linear and quadratic effect, respectively, on CEY. Optimum conditions were achieved at 21.8 min, 250 rpm, and 60°C. Under these optimized conditions, the estimated value for CEY was 378.1 µg ß-carotene equivalents/g of DPP, corresponding to 61.6% of the total carotenoid content present in the DPP. In contrast, the observed experimental value was 373.2 µg ß-carotene equivalents/g of DPP (61.2%). The experimental value was very close to the estimated value, which verifies the model's adequacy and fit. This study shows an alternative method to extract carotenoids from DPP with canola oil, obtaining an oil naturally enriched with carotenoids that could be used as a potential functional ingredient in the development of food, cosmetics, and medicinal products. PRACTICAL APPLICATION: Pumpkin by-products are a potential carotenoid source. Vegetable oil can be used as an alternative solvent for carotenoid extraction from pumpkin residues to obtain an enriched carotenoid oil that can be used to formulate food products.
Subject(s)
Carotenoids/isolation & purification , Chemical Fractionation/methods , Cucurbita/chemistry , Plant Extracts/chemistry , Plant Oils/chemistry , Solvents/chemistry , Carotenoids/analysis , TemperatureABSTRACT
Resumen El cultivo intensivo de peces es una estrategia econòmicamente importante para producir alimento. Sin embargo, las prácticas de cultivo intensivo generan estrés oxidativo e inmunosupresión, lo que ocasiona pérdidas de la calidad del especimen y aumento en la mortalidad. Para contrarrestar estos efectos, se ha optado por la administración de vegetales como fuente de polifenoles con propiedades antioxidantes e inmunoestimulantes en peces carnívoros de cultivo. El objetivo de este trabajo fue describir los efectos de los polifenoles de origen vegetal como antioxidantes e inmunoestimulantes en peces carnívoros, y promover su uso como ingredientes funcionales en la acuicultura. Los vegetales como fuente de polifenoles tienen la capacidad de mejorar los sistemas de defensa inmune y antioxidante de las especies analizadas, con un tejido de mejor calidad nutricional y un mayor contenido endógeno de antioxidantes. No obstante, las propiedades biológicas de los polifenoles dependen del tipo y concentra ción en el vegetal, de la dosis y el tiempo de administración, así como de la matriz alimentaria, la cual determina la bioaccesibilidad y biodisponibilidad de los polifenoles en el organismo. Es la información generada sobre el efecto de los polifenoles en la calidad post mortem, por lo que se deben realizar más estudios.
Abstract Fish production by intensive aquaculture, is an economically important strategy to produce food. However, intensive fish farming generates oxidative stress and suppress the immune system, causing loss of product quality and increasing fish mortality rates. To diminish these effects, plants as a source of polyphenols with antioxidants and immunostimulant properties were administered to carnivorous farmed fish. The aim of this study was to describe the effects of plant polyphenols as antioxidants and immunostimulants on carnivorous fish, and to promote their use as functional ingredients in aquaculture. Plants as a source of polyphenols showed the ability to improve the immune and antioxidant defense systems of the analyzed species, resulting in a tissue of better nutritional quality and a higher endogenous antioxidant content. However, the biological properties of polyphenols are dependent on the type of plant and their concentration within it, the dose and the time of administration, as well as the food matrix, which determines their bioaccessibility and bioavailability in the organism. There is little information on the effec of polyphenols in post mortem quality; therefore, further studies should be conducted.
