Effect of palm olein addition on the quality characteristics of sunflower oil during deep fat frying

The aim of the present study was to investigate the effects of palm olein (PO) addition on the quality characteristics of sunflower oil (SFO) during frying of potato pieces. The blends were prepared in the volume ratios of 20:80 (PO:SFO, PSF1) and 40:60 (PO:SFO, PSF2). Refractive index, free fatty acid content, peroxide value, p-anisidine value, TOTOX, viscosity, specific extinction, polar compounds, food oil sensor value, colour, and polymer content of the oils all increased, whereas iodine value and C18:2/C16:0 ratio decreased as frying progressed. The percentage of linoleic and linolenic acids tended to decrease, whereas the percentages of palmitic and oleic acids increased. Based on the most oxidative stability criteria investigated, PO addition led to a slower deterioration of SFO at frying temperature. Blend PSF2 showed better frying performance compared to PSF1. However, higher amounts of free fatty acids and higher colour units were both detected in the blends compared to pure SFO at the end of frying. It appears that proper blending of highly unsaturated SFO with PO can result in oil blends that could meet nutritional needs with improved stability for domestic cooking and deep-frying

(-)-glaciantarcin, a new dipeptide and some secondary metabolites from the psychrophilic yeast Glaciozyma antarctica PI12

A new dipeptide, (-)-glaciantarcin (1) and three known compounds, cyclo(-Pro-Gly) (2), 1-(2-deoxypentofuranosyl)-5-methyl-2,4(1H,3H)-pyrimidinedione (3) and vidarabine (Ara-A) (4), were isolated from Glaciozyma antarctica PI12, a cold-adapted yeast. The chemical structures were elucidated by FT-IR, NMR and mass spectrometry. The cytotoxicity and antioxidant activities of compounds 1-4 were evaluated by using the MTT bioassay on MCF-7 (human breast cancer cell line), PC-3 (human prostate cancer cell line) and HEK-293 (normal human embryonic kidney cell line) and DPPH free radical scavenging activity, respectively. At concentration of 400 μM, all compounds showed the highest activity on MCF-7, with compound 1 at 65%, compound 2 (70%), compound 3 (66%) and compound 4 (58%) cell viability. All compounds exhibited weak antioxidant properties. To the best of our knowledge, this is the first report of compounds 1-4 from Glaciozyma antactica

Effect of microwave heating on oxidative degradation of sunflower oil in the presence of palm olein

The aim of this study was to evaluate on how heat treatments by microwave oven may affect the oxidative degradation of sunflower oil (SFO) and its blend with palm olein (PO). The blend was prepared in the volume ratio of 40:60 (PO: SFO, PSF). The samples were exposed to microwave heating at medium power setting, for different periods. In this study, refractive index, free fatty acid content, peroxide value, p-anisidine value, total oxidation (TOTOX), specific extinction, viscosity, polymer content, polar compounds and food oil sensor value of the oils all increased, whereas iodine value and C18:2/C16:0 ratio decreased as microwave heating progressed. Microwave heating temperature increased with increasing heating time and longer heating times resulted in a greater degree of oil deterioration. The percentage of linoleic acid tended to decrease, whereas the percentage of palmitic acid increased. The effect of adding PO to SFO on the formation of free fatty acids and conjugated dienes during microwave treatment was not significant (p< 0.05). No significant differences in food oil sensor value was observed between SFO and PSF. Based on the most oxidative stability criteria, it can be concluded that the microwave heating caused the formation of comparatively lower amounts of oxidation products in PSF compared to SFO, indicating a lower extent of oxidative degradation of PSF

Emissions of Transesterification Jatropha-palm Blended Biodiesel

This paper deals with emissions of transesterification Jatropha-Palm blended biodiesel as fuel for 4-stroke single vertical cylinder diesel engine. The engine emissions of Carbon Monoxide (CO), Carbon Dioxide (CO2) and Nitrogen Oxides (NOx) were analyzed and discussed. All tests were carried out at varied load conditions which were 0.13, 0.15, 0.17, 0.19 and 0.21 kW. The results revealed that higher CO, CO2 and NOx produced from all biodiesel blended as compared to Diesel Fuel (DF). This might be due to the higher oxygen content in the biodiesel structure and also higher exhaust temperature during combustion which promotes the formation of more hazardous gases

Effect of microwave heating with different exposure times on the degradation of corn oil

In the present work, the influence of microwave power and heating times on the quality degradation of corn oil was evaluated. Microwave heating test was carried out using a domestic microwave oven for different periods at low- and medium-power settings for the corn oil sample. The changes in physicochemical characteristics related to oil degradation of the samples during heating were determined by standard methods. In this study, refractive index, free fatty acid content, peroxide value, p-anisidine value, TOTOX value, viscosity and total polar compound of the oils all increased with increasing heating power and time of exposure. In GLC analysis, the percentage of linoleic acid tended to decrease, whereas the percentage of palmitic, stearic and oleic acids increased. The C18:2/C16:0 ratio decreased in all oil samples with increasing heating times. Exposing the corn oil to various microwave power settings and heating periods caused the formation of hydroperoxides and secondary oxidation products. The heating reduced the various tocopherol isomers in corn oil and highest reduction was detected in ?-tocopherol. Longer microwave heating times resulted in a greater degree of oil deterioration. Microwave heating caused the formation of comparatively lower amounts of some degradative products in the oil samples heated at low-power setting compared to medium-power setting. The present analysis indicated that oil quality was affected by both microwave power and heating time

LARP1 post-transcriptionally regulates mTOR and contributes to cancer progression

RNA-binding proteins (RBPs) bind to and post-transcriptionally regulate the stability of mRNAs. La-related protein 1 (LARP1) is a conserved RBP that interacts with poly-A-binding protein and is known to regulate 5′-terminal oligopyrimidine tract (TOP) mRNA translation. Here, we show that LARP1 is complexed to 3000 mRNAs enriched for cancer pathways. A prominent member of the LARP1 interactome is mTOR whose mRNA transcript is stabilized by LARP1. At a functional level, we show that LARP1 promotes cell migration, invasion, anchorage-independent growth and in vivo tumorigenesis. Furthermore, we show that LARP1 expression is elevated in epithelial cancers such as cervical and non-small cell lung cancers, where its expression correlates with disease progression and adverse prognosis, respectively. We therefore conclude that, through the post-transcriptional regulation of genes such as mTOR within cancer pathways, LARP1 contributes to cancer progression