5 research outputs found
Extraction of High-Value Lipids and Phenolic Compounds from Sorghum Bran via a Sequential Supercritical Carbon Dioxide Approach
No full textSorghum bran, containing high-value
lipids and phenolic compounds,
is an underutilized food processing byproduct. This study developed
and optimized a green method based on a sequential pure supercritical
carbon dioxide (SC–CO2) and ethanol/water-modified
SC–CO2 extraction to extract wax-rich lipids and
phenolic compounds from sorghum bran in a single step. The extraction
conditions, namely, temperature (20–100 °C), pressure
(20–40 MPa), extraction time (0.5–5 h), and cosolvent
type (ethanol or ethanol–water), were optimized for the highest
wax-rich lipids and phenolics extraction yields. In the first part,
neat SC–CO2 at 40 MPa and 60 °C resulted in
the highest lipid yield (6.2%, w/w dry basis), which contained ∼5%
(w/w) high-melting point waxes. The purified wax fractions containing
phytosterols showed high melting points of 57–87 °C. In
the second part, the highest total phenolics and flavonoids yields
were achieved at 40 MPa and 40 °C via 15% (w/w)
ethanol–water (1:1, v/v) modified SC–CO2 by
150 ± 3 mg of gallic acid equivalent (GAE)/100 g of bran (dry
basis) and 99.6 ± 4 mg of catechin equivalent (CAE)/100 g of
bran (dry basis), respectively. Overall, this study provides a novel
single-step extraction approach based on SC–CO2 to
extract and fractionate lipids and phenolic compounds from sorghum
bran
Biolipid Production by the Oleaginous Yeast Rhodosporidium Toruloides Using Apple Pomace as a Primary Carbon Source
No full textValorization of Apple Pomace Via Single Cell Oil Production Using Oleaginous Yeast Rhodosporidium toruloides
No full text© 2022, The Author(s), under exclusive licence to Springer Nature B.V.Apple pomace was used as a sole raw material for single cell oil (SCO) production by the oleaginous yeast Rhodosporidium toruloides DSM 4444. Preliminary studies with glucose medium revealed 100 mL of working volume in 500 mL Erlenmeyer flask as the most efficient in terms of lipid content. Thus, apple pomace hydrolysate was tested in six different conditions using 100 mL medium. The detoxified hydrolysate without chemical supplement (D medium) was found to be the most viable medium by 47.5 ± 2.47% lipid on dry cell basis (w/w). Apple pomace hydrolysate was also proven effective for SCO productions in bench-top fermenter (1 L working volume) under controlled temperature (25 °C), pH (5.0), and aeration (1vvm) by 40.1 ± 5.51% (w/w) lipid content. The same medium resulted in 50.9% (w/w) lipid on a dry cell basis in 30 L industrial-type bioreactor with 10 L of working volume, without exact control of temperature and pH. The results confirm that apple pomace is a prosperous raw material for SCO production in flask and fermenter scales. Graphical Abstract: [Figure not available: see fulltext.]
biomass
No full textThe purpose of this study is to evaluate the effect of high hydrostatic pressure (HHP) as a novel approach for yeast cell disruption and lipid extraction from Lipomyces starkeyi DSM 70295 grown in glucose medium (40 g/L and C/N:55/1) at initial pH of 5.0, 25 degrees C, and 130 rpm for 8 days. HHP extraction conditions including pressure, time, and temperature were optimized by response surface methodology. The high speed homogenizer-assisted extraction (HSH) was also used for comparison. The biomass subjected to HHP was examined under scanning electron microscopy and light microscope. A maximal lipid yield of 45.8 +/- 2.1% in dry cell basis (w/w) was achieved at 200 MPa, 40 degrees C, and 15 min, while a minimum yield of 15.2 +/- 0.9% was observed at 300 MPa, 40 degrees C, and 10 min (p < 0.05). The lipid yield decreased with increasing pressure. It was demonstrated that low pressure (200 MPa) collapsed the cells, while high pressure (400 MPa) created protrusions on the cell wall and cell fragments spread in the environment. This study favors HHP as a promising method for Lipomyces oil extraction. Practical Application Single-cell oils are considered future alternatives to plant-based oils as food additives and dietary supplements. Oleaginous microorganisms accumulate oils in their cell plasma, which makes extraction essential. One of the main obstacles with existing methods is the utilization of strong acids to destroy cell walls. This study aims to demonstrate high hydrostatic pressure as a rapid method for lipid extraction from oleaginous yeast Lipomyces starkeyi
Extraction of Anthocyanins from Purple Sweet Potato Using Supercritical Carbon Dioxide and Conventional Approaches
No full textThis research investigates the potential of supercritical carbon dioxide (SC-CO2) technology as a green and sustainable approach to improve anthocyanin extraction from purple sweet potatoes (PSP). The study explored different extraction parameters (i.e., temperatures of 35–55 °C, cosolvent concentrations of 10–30 % (w/w), ethanol ratios of 30–70 % (v/v), pressures of 30–40 MPa, extraction times of 120–180 min, and solvent: sample ratios of 25:1–45:1(v/w)), to optimize the total phenolic content (TPC), anthocyanin content (ANC), and antioxidant activity (AA). Additionally, conventional extraction methods using different solvent (ethanol and methanol) mixtures, solvent: sample ratios (15:1; 45:1; 6:1 (v/w)), temperatures (35–50 °C), and extraction times (50–60 min) were performed for the extraction of phenolic compounds from PSP. The highest TPC (340 mg GAE/g dry PSP), ANC (136 mg C3G/100 g dry PSP), and AA (ABTS (7.3 mg TEV/g dry PSP), DPPH (18.2 mg TEV/g dry PSP), and FRAP (1399 mg GAE/100 g)) were achieved with 30 MPa, 35 °C and 20 % cosolvent concentration operated for 180 min. These findings underscore the use of SC-CO2 extraction to obtain anthocyanin extracts that can potentially be used as a coloring agent in the food industry. The proposed SC-CO2 extraction method provides an eco-friendly alternative to conventional methods for extracting phenolic compounds
