Effect of Flourensia cernua Bioactive Compounds on Stability of an Oil-in-Water (O/W) Emulsion

The stability of O / W emulsions cannot be controlled by just the emulsifier additives; antioxidants are needed to improve the stability of the emulsified system and protect against lipid oxidation. This study aimed to evaluate the effect of the bioactive compounds of tarbush Flourensia cernua as natural stabilizers of an oil-in-water (O/W) emulsion based on glycerol, gum arabic, jojoba oil, and candelilla wax under refrigeration conditions. The samples were coded as EBCT (emulsion with bioactive compounds of tarbush) and CE (control emulsion). These were characterized in terms of opacity and transparency and evaluated in terms of the system's stability, antioxidant activity, and microbiological analysis during storage. EBCT showed higher transmittance and minor opacity concerning CE. Bioactive compounds of tarbush showed higher antioxidant activity in oil in water emulsion, as measured by ABTS and DPPH. The microbiological analysis results demonstrated that bioactive compounds presented a higher fungistatic effect on yeast growth in the emulsion. EBCT showed higher stability, antioxidant, and fungistatic activity relative to CE, without any significant storage differences during 4 weeks in refrigeration conditions. This research provides the agri-food industry interesting results to formulate a stabilized green emulsion with bioactive compounds of tarbush.

Candelilla Wax Edible Coating with Flourensia cernua Bioactives to Prolong the Quality of Tomato Fruits

The improvement of the postharvest quality of tomato fruits was evaluated using an edible coating functionalized with an Flourensia cernua extract evaluating the antifungal, structural, barrier, and optical properties. The formulation and evaluation of an edible coating and its application on tomato was evaluated using a response surface methodology to determine the ideal concentrations of candelilla wax, whey protein, and glycerol. Edible films showed good barrier properties, with water vapor permeability varying from 0.435–0.404 g mm/m2 day kPa. The addition o F. cernua extract showed significant improvement in the transparency of films. The edible coating applied to tomato reduced weight and firmness loss. The sensory evaluation proved that the product obtained is acceptable for consumers. The edible coating added with F. cernua extract was the most effective in inhibiting the growth of pathogenic fungi and the visual appearance at the end of storage confirmed the beneficial effect of the edible coating.

Efectividad in vitro de Bacillus y polifenoles de plantas nativas de México sobre Rhizoctonia-Solani

Con el objetivo de encontrar alternativas para el manejo de patógenos que provocan enfermedades en el sistema radical de las plantas se evaluó el efecto in vitro de bacterias antagonista del género Bacillus aisladas de la rizosfera y de extractos etanolicos de plantas de las especies Larrea tridentata, Flourensia cernua, Opuntia f icus-indica, Agave lechuguilla y Yucca filifera endémicas del desierto Chihuahuense contra el fitopatógeno Rhizoctonia solani. Las bacterias se obtuvieron de la forma esporulada, una suspensión de suelo se calentó 15 min 80 °C para eliminar formas no esporuladas. Los extractos vegetales se obtuvieron por infusión. Como resultado se encontró que las cepas de Bacillus aislados presentan un efecto antagonista in vitro sobre la inhibición micelial de Rhizoctonia solani desde 40 a 67%. La caracterización por secuenciación del gen 16S del ADNr se determinó que los aislamientos pertenecen a las especies de B. subtilis, B. pumilus y a B. atrophaeus, quienes están reportadas con efecto antagónico sobre organismos fitopatógenos. Para el caso de los extractos se encontró un efecto en la inhibición micelial hasta 100% en su mayoría todos los extractos inhibieron el crecimiento del micelio de R. solani al 100% excepto el extracto de Y. filifera que solo tuvo 46% con la dosis más alta evaluada (3 000 ppm). Los extractos de F. cernua muestran que a 160 ppm de polifenoles totales se inhibe completamente a R. solani.