Ultrasound-assisted extraction of fructans from agave (Agave tequilana Weber var. azul) at different ultrasound powers and solid-liquid ratios

Abstract

The effects of ultrasound-assisted extraction (UAE) at different ultrasound power densities (UPDs; 40, 80, and 120 mW/mL) and solid:liquid (S:L) ratio (1:2, 1:3, and 1:6) on the extraction of carbohydrates from Agave tequilana plant of different ages were evaluated. Extracts obtained (6-and 7-year-old plant) were analyzed in the yield of carbohydrates (YC), fructan (FRU) content, simple sugars, fructan profile and the average degree of polymerization (DP n ). UPD, S:L ratio, and plant age all affected YC, FRU, and DP n . Maximum YC and FRU were obtained from the older agave with UPD and S:L ratio of 120 mW/mL and 1:6, respectively; while glucose, fructose, and sucrose were highly released from the younger plant. Agave of 7-year-old presented the highest DP n . Fructan degradation occurred at high UPD, increasing the simple sugars and decreasing the DP n . Thermal-traditional extraction without sonication caused more fructan degradation; and overall, ultrasound enhanced fructan extraction and minimized fructan damage, representing a technological alternative for fructan extraction from agave.Keywords: agave; fructans; ultrasound; power density; solid:liquid ratio; plant age.Practical Application: Agave tequilana Weber var. azul plants have significant amounts of fructans. Extraction of these components by alternative methods such as ultrasound could represent advantages, improving the extraction and product quality. This research presents an alternative for the extraction of fructans assisted with ultrasound, evaluating different powers and solid-liquid ratios from agave heads of two different ages. Both variables, as well as age of agave showed a strong effect on fructan extraction. Ultrasound enhanced the extraction and minimized fructan damage, representing a technological alternative.

Canola Oil with High Antioxidant Content Obtained by Combining Emerging Technologies: Microwave, Ultrasound, and a Green Solvent

“…The increase in ultrasound amplitude implies an increase in absorbed power, favoring the extraction process, which was observed in the increasing trend of the yields with the amplitude (Figure b–d,f).…”

“…). Ultrasound produces changes and ruptures in the cell walls due to microcavitation, facilitating the release of cell components . The highest TTC content was observed for the extraction with ethanol 96%, while the oil extracted with ethanol 99% from pretreated seeds had the lowest TTC content, being lower than that of the oil obtained with the same solvent but without pretreatment.…”

“…As for extraction time, yields ( Y 1 and Y 2 ) increase with time, but a long exposure time to ultrasound waves could promote tocopherol degradation ( Y 3 ). On the other hand, the increase in temperature favors the extraction of components, but it also causes the formation of cavitation microbubbles that implode easily but release less energy, reducing the mass transfer intensity. This opposite behavior can be observed in the curvature of the response surfaces shown in Figure g,h, where the effect of increased solubility and diffusion seem to predominate.…”

“…studied the extraction of canola oil with ethanol in a stirred batch device from microwave‐pretreated seeds, also reaching the same oil yield to that obtained with hexane. Ultrasound is an emerging technology used for the extraction of various compounds from different matrices . Ultrasonic waves applied to a liquid medium can produce micro cavitation bubbles whose collapse releases energy at localized points, causing the rupture of biological structures and facilitating the release of compounds within the solution …”

Tiempo de pasteurización y su respuesta en las características químicas y de capacidad antioxidante de aguamiel de Agave americana L.

“…Azúcares reductores: Es un método en que se emplea 3,5-ácido dinitrosalicílico para la hidrólisis de polisacáridos presentes en una muestra, seguido de la determinación espectrofotométrica (Espectrofotómetro UV-2600, Shimadzu) a 540 nm de los azúcares reductores (Sánchez-Madrigal et al, 2017).…”