Production of flavor compounds from olive mill waste by Rhizopus oryzae and Candida tropicalis

Abstract

The purpose of this study was to investigate the production of flavor compounds from olive mill waste by microbial fermentation of Rhizopus oryzae and Candida tropicalis. Olive mill waste fermentations were performed in shake and bioreactor cultures. Production of flavor compounds from olive mill waste was followed by Gas Chromatography–Mass spectrometry, Gas chromatography- olfactometry and Spectrum Sensory Analysis®. As a result, 1.73-log and 3.23-log cfu/mL increases were observed in the microbial populations of R. oryzae and C. tropicalis during shake cultures, respectively. C. tropicalis can produce a higher concentration of d-limonene from olive mill waste than R. oryzae in shake cultures. The concentration of d-limonene was determined as 185.56 and 249.54 μg/kg in the fermented olive mill waste by R. oryzae and C. tropicalis in shake cultures respectively. In contrast, R. oryzae can produce a higher concentration of d-limonene (87.73 μg/kg) d-limonene than C. tropicalis (11.95 μg/kg) in bioreactor cultures. Based on sensory analysis, unripe olive, wet towel, sweet aromatic, fermented aromas were determined at high intensity in olive mill waste fermented with R. oryzae meanwhile olive mill waste fermented with C. tropicalis had only a high intensity of unripe olive and oily aroma.

Currently Applied Extraction Processes for Secondary Metabolites from Lippia turbinata and Turnera diffusa and Future Perspectives

“…Through an extraction with MeOH-CH2Cl2, M. tuberculosis was completely inhibited at 100 μg/mL (this extract contained the new four compounds), showing the antimycobacterial activity for Lippia species for the first time [64]. Therefore, Limonene's derivatives, such as perillyl alcohol, menthol, carveol, and α-terpineol, are widely applied in food, pharmaceuticals, cosmetics, biomaterials, and biofuels [96][97][98]. α-Thujone (a monoterpenoid ketone) is considered a toxic compound [99] in humans and the cause of a syndrome called "absinthism", which was described in the 19th century after chronic abuse of the thujone-containing spirit [100].…”

“…Additionally, it is one of the most important exogenous biomarkers denoting a deficient liver metabolism, and is accumulated due to the liver's incapacity to convert it into carveol metabolites or perillyl metabolites by CYP2C enzymes [92][93][94][95]. Limonene's derivatives, such as perillyl alcohol, menthol, carveol, and α-terpineol, are widely applied in food, pharmaceuticals, cosmetics, biomaterials, and biofuels [96][97][98]. α-Thujone (a monoterpenoid ketone) is considered a toxic compound [99] in humans and the cause of a syndrome called "absinthism'', which was described in the 19th century after chronic abuse of the thujone-containing spirit [100].…”

BIODEGRADACIÓN DE PLAGUICIDAS ORGANOFOSFORADOS Y ORGANOCLORADOS POR Candida tropicalis Y Stenotrophomonas maltophilia EN MICROCOSMOS DEL SUELO

“…Otros autores, como Basak et al (2013), encontraron una temperatura óptima de 30 ºC a pH de 6 y 150 rpm en ensayos para la degradación de 4-clorofenol. Aunque no se ha probado el efecto de la aireación sobre el crecimiento de C. tropicalis, sí se ha reportado su actividad en fermentadores aireados con 0.325 vvm (Guneser et al 2016). Chandran y Das (2012) reportaron valores de producción de biomasa de 3.5 g/L a 35 ºC y pH 5 con dichos parámetros de cultivo, mientras que Mohamad et al (2013) reportaron 12 g/L.…”

The Dark Side of Microalgae Biotechnology: A Heterotrophic Biorefinery Platform Directed to ω-3 Rich Lipid Production

“…Most of the recent works reporting lipid/DHA production from heterotrophic microalgae use traditional methods to monitor the microalgae growth during the culture development, such as optical density, dry cell weight and cell counting [19,[22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. However, these techniques provide no information on cell physiological states.…”