Ultrasound assisted modulation of yeast growth and inactivation kinetics

Sulforaphane (SFN) is a health-promoting compound occurring in broccoli. It is formed by action of myrosinase in a two-step reaction that also yields undesirable compounds such as nitriles and isothionitriles. Different techniques affecting enzyme activity and tissue integrity were proposed to increase SFN content in the edible parts and discards of broccoli. Ultrasound processing is an emerging technology that produces these effects in foods, but has been poorly explored in broccoli so far. The aim of this work was to study the effect of ultrasound-assisted blanching on myrosinase activity and SFN content in broccoli florets. Myrosinase showed first-order inactivation kinetics in blanching at different temperatures with and without ultrasound processing. The inactivation rate was faster using ultrasound, with kinetic constants two orders of magnitude higher than without ultrasound. The activation energy (Ea) in traditional blanching (57.3 kJ mol−1) was higher than in ultrasound-assisted blanching (15.8 kJ mol−1). Accordingly, ultrasound accelerates myrosinase inactivation. The blanching time and temperature significantly affected myrosinase activity and SFN content. At 60 °C and 4 min of ultrasound-assisted blanching, myrosinase activity was minimum and SFN content was the highest. These findings may help to design SFN enrichment processes and will contribute to the valorization of agro-industrial wastes.

Download Full-text

Contrast-Enhanced Ultrasound Assisted Surgery of Intramedullary Spinal Cord Tumors: Analysis of Technical Benefits and Intra-operative Microbubble Distribution Characteristics

Ultrasound in Medicine & Biology ◽

10.1016/j.ultrasmedbio.2020.10.017 ◽

2020 ◽

Author(s):

Ignazio G. Vetrano ◽

Antonio G. Gennari ◽

Alessandra Erbetta ◽

Francesco Acerbi ◽

Vittoria Nazzi ◽

...

Keyword(s):

Spinal Cord ◽

Distribution Characteristics ◽

Contrast Enhanced Ultrasound ◽

Spinal Cord Tumors ◽

Intramedullary Spinal Cord ◽

Contrast Enhanced ◽

Ultrasound Assisted

Download Full-text

Studies concerning the molecular complexation of Lippia sidoides essential oil in β-cyclodextrin by conventional and ultrasound assisted method

Planta Medica ◽

10.1055/s-0033-1352375 ◽

2013 ◽

Vol 79 (13) ◽

Author(s):

PN Ferraz-Freitas ◽

CR Souza ◽

WP Oliveira

Keyword(s):

Essential Oil ◽

Lippia Sidoides ◽

Molecular Complexation ◽

Ultrasound Assisted

Download Full-text

Innovative Extraction Techniques for the Optimum Extraction of Phenolic Compounds from Peanut Meal and Evaluation of Their Biological Activities

Advances in Nutrition & Food Science ◽

10.33140/anfs.04.02.2 ◽

2019 ◽

Vol 4 (2) ◽

Keyword(s):

Phenolic Compounds ◽

Carcinoma Cell ◽

Biological Activities ◽

Peanut Meal ◽

Ultrasound Assisted Extraction ◽

Carcinoma Cell Lines ◽

Assisted Extraction ◽

Phenolic Extract ◽

Ultrasound Assisted ◽

Water Ratio

There is a worldwide demand for phenolic compounds (PC) because they exhibit several biological activities. This work aimed at extracting phenolic compounds from peanut meal. The methods of extraction were mainly: conventional solvent extraction (traditional methods) and ultrasound assisted extraction (recent methods) and comparing their results. Peanut meal (PM) was prepared by defatting with n-hexane, and then extracted by the two previous methods. First, the conventional solvents used were 80% methanol, ethanol, acetone, isopropanol, and distilled water. Then studied Different parameters such as meal: water ratio, also the effect of temperature and the pH on the extraction process. Second, ultrasonic assisted extractions (USAE), the parameters investigated were temperature, time and speed of sonication. Finally, all the extracts were analyzed by HPLC for their phenolic contents. Results indicated that the highest extracted PC achieved by solvents was in distilled water where 1:100, Meal: Water ratio which extracted 40 mg PC / g PM at 30& 35°C. Highest extracted PC was achieved by alkaline medium at pH 12 more than acidic and neutral medium. While (USAE) at speed 8 ultrasonication and temperature 30ᵒC, extracted 49.2mg PC /g PM. Sothe ultrasound assisted extraction exhibited great influence on the extraction of phenolic compounds from peanut meal. The ultrasonic peanut extract was examined for its antioxidant, antimicrobial and anticarcinogenic activities. The antioxidant activity of PM phenolic extract prepared by ultrasonic technique, was measured by, β-carotene, and DPPH methods, and reducing antioxidant power. Results revealed values: 84.57, 57.72 and 5960 respectively. The PM extract showed different levels of antimicrobial activity against the pathogenic bacteria used. As for the anticarcinogenic effect PM phenolic extract most effective on inhibiting colon carcinoma and lung carcinoma cell lines with IC50 = 20.7 and 20.8 µ/ml., respectively. This was followed by intestinal carcinoma and liver carcinoma cell lines with IC50= 39.6 and 40.2µ/ml.

Download Full-text