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Yogurt is generally obtained from milk fermentation using lactic acid bacteria (LAB). However, yogurt is prone to damage. Therefore, to study damage and contamination on yogurt, additional treatments like fortification are being investigated. In this study, the effect of an audiosonic wave on microbes in yogurt with variations in temperature of 4 °C, 25 °C, and 38 °C and 14 days of storage time with a specified frequency of 8000 Hz has been carried out. This study aims to determine the shelf life of yogurt with audiosonic wave exposure using the Accelerated Shelf Life Testing (ASLT). Organoleptic tests showed that the physical characteristics of yogurt decreased in quality. The shelf life of yogurt without audiosonic wave exposure at 4 °C, 25 °C, and 38 °C was 34.9 days, 24.4 days, and 20.1 days. Meanwhile, for yogurt with audiosonic wave exposure (YCA) the results were 30.7 days, 23.4 days, and 20.2 days, respectively. It can be concluded that the yogurt sample with the addition of the audiosonic exposure had a shorter shelf life and decreased quality faster than yogurtwithout the addition of the treatment; therefore, audiosonics can potentially damage the shelf life of yogurt. [ABSTRACT FROM AUTHOR]

The unwieldiness of Fenton reaction on biodegradation of methyl orange (MO) by brown-rot fungus Gloeophyllum trabeum was investigated based on Fe2+-dependent reaction. The degradation of MO (final concentration 75 mg/L) was performed in mineral salt media with and without Fe2+ with incubation period at 0, 7, 14, 21, and 28 days. Degradation analysis was performed using UV-Vis Spectrophotometer and LC-TOF/MS. The highest MO degradation occurred during 28 days incubation, which approximately 46.67% and 38.89% in medium with and without Fe2+, respectively, indicated that the presence of Fe2+ enhanced MO degradation. C15H18N3O5S− and C17H22N3O7S− were the metabolic products of MO degradation in mineral salt medium with Fe2+. The MO pathway by G. trabeum was stated by termination on double bond of the azo group and followed by hydroxylation to C15H18N3O5S−, and then undergoes methylation to C17H22N3O7S−. This study assumed that Fenton reaction might be involved in MO biodegradation by G. trabeum. [ABSTRACT FROM AUTHOR]