Biofuel Production from Waste Cooking Oils and its Physicochemical Properties in Comparison to Petrodiesel

Haphazard mining and consumption of fossil fuels have reduced petroleum reserves causing fossil fuel depletion and environmental degradation; thus, reflecting the need for the cheaper, renewable and eco-friendly alternative source of petroleum to meet the fuel demand. A million liters of edible oil used for cooking foods and date expired oils from oil manufacturers are discarded into sewage. This study primarily intends to study the feasibility of biodiesel production using such waste oils. In this work, biodiesel was prepared from waste cooking oils by a process called transesterification with NaOH as a catalyst. Our results showed that methyl ester (biodiesel) (92.67±0.90%), soap materials (1.33±0.224%), and glycerol (6±0.68%) were obtained after the transesterification of waste cooking oil. The physicochemical properties of biodiesel such as density, viscosity, volatility, surface tension, and flashpoint were analyzed, which were found to be 0.862±0.006 g/cm3, 2.23±0.021 cP, 0.327×10-3±4.5×10-6 g/s, 32.03±0.138 dyne/cm, 169.67±0.810°C, respectively. These properties were compared with that of commercial diesel as well as with the values specified by the American Society for Testing and Materials (ASTM) D6751. The density and the surface tension of the biodiesel were found similar to that of petrodiesel but its volatility was 3 times lower. Fourier-transform infrared spectroscopy (FTIR) spectra of the biodiesel showed methyl ester functional group at 1436 cm-1. Based on the cost of the materials used for production, the cost of biodiesel was estimated to be about 81 Nepalese rupees (0.67 USD) per liter. The properties of biodiesel also met the standard values of ASTM D6751. These findings indicate that waste oil is one of the feasible biodiesel sources and it can be used as a suitable alternative to petrodiesel

Atraumatic splenic rupture associated with apixaban.

Apixaban is a direct oral anticoagulant that works by inhibiting factor Xa. It has been associated with adverse bleeding outcomes including atraumatic splenic rupture. We present the case of an 86-year-old man who presented with features of left upper abdominal pain and hemorrhagic shock found to have atraumatic splenic rupture and hemoperitoneum on imaging

LC-MS based metabolite profiling, in-vitro antioxidant and in-vivo antihyperlipidemic activity of Nigella sativa extract

The aim of this study was to identify the bioactive phytoconstituents present in the aqueous extract of Nigella sativa and also, to evaluate the antioxidant and antihyperlipidemic activity in Wistar rats. The LC-MS/MS analysis was assessed for the determination of different bioactive compounds present in N. sativa extract. Total phenolic and flavonoid content were determined by using validated Folin-Ciocalteu and Aluminum chloride colorimetric methods, respectively. The in-vitro antioxidant and in-vivo antihyperlipidemic activity in Wistar rats were also evaluated. Preliminary phytochemical screening of the extract showed the presence of alkaloids, flavonoids, phenols, glycosides, and amino acids in the aqueous extract. The bioactive compounds of the aqueous extract were identified through LC-MS/MS analysis. The in-vitro antioxidant activity of N. sativa showed the highest free radical scavenging capacity in DPPH, H2O2, and OH radical scavenging assays with IC50 values 11.916 ± 2.828, 30.294 ± 13.790, and 12.048 ± 2.828 µg/mL, respectively. Evaluation of antihyperlipidemic activity of extract in Wistar rats showed that a high dose (800 mg/kg) of extract significantly decreased total cholesterol (TC) 71.76 ± 6.91 mg/dL, TG 83.6 ± 8.09 mg/dL, low-density lipoproteins (LDL-c) 33.86 ± 6.05 mg/dL, very low-density lipoproteins (VLDL-c) 16.72 ± 1.61 mg/dL level in blood. However, the HDL-C level was significantly improved (21.18 ± 1.80 mg/dL) as compared to HFD-induced control rats (11.76 ± 1.14 mg/dL) after 28 days of treatment. Also, at the same dose, animal body weight was also decreased to 162.6 ± 16.40 g compared with control 184.4 ± 10.24 g. The aqueous extract of N. sativa was found to be an effective natural source of antioxidant and hypolipidemic agents. This activity was attributed to the presence of diverse bioactive compounds in it

Potential surface active agent production using very low grade and cheap substrate by Bacillus subtilis as microbial cell factory

Bio-surfactants are surface-active molecules which are produced by the wide range of microbes including bacteria, fungi, moulds, and yeast. This study was conducted to identify bio-surfactants by Bacillus subtilis combined with use of cheap substrates and industrial wastes (Mustard cake, Whey and Soya cake) which are found locally in Nepal. Bacillus subtilis, one of the most potential bio-surfactants producer; was isolated from soil sample of hydrocarbon contaminated site. Isolates were grown in a Minimal Salt Media (MSM) with 10% (v/v) mustard oil cake, whey and soya cake separately. The presence and potential of surfactant was determined by the oil spreading technique, emulsification index (%E24) and surface tension measurement. It was revealed that the surface tensions of cell free extract were 54.41, 60.02 and 56.64 mN/m for from mustard cake, whey and soya cake respectively as compared to distilled water (72.09) at 25oC. The emulsification index values was found to be highest in engine oil from the bio-surfactant extracted from mustard cake, soya cake and whey respectively. Similarly, mustard oil showed the lowest value of emulsification index. The highest emulsification activity was shown in mustard oil i.e. 1.13 from the cell free extract from mustard oil and lowest in engine oil i.e., 0.07, by the extract from soya cake medium, when measured in spectrophotometer at 540 nm. In conclusion, strain of Bacillus subtilis was found to be the potential surface active agent producers on the mustard oil cake, which can be useful medium for various environmental, food, medicinal and industrial processes

Total Phenolic Content, Flavonoid Content and Antioxidant Potential of Wild Vegetables from Western Nepal

Eight selected wild vegetables from Nepal (Alternanthera sessilis, Basella alba, Cassia tora, Digera muricata, Ipomoea aquatica, Leucas cephalotes, Portulaca oleracea and Solanum nigrum) were investigated for their antioxidative potential using 2,2-dyphenyl-1-picrylhydrazyl (DPPH) scavenging, hydrogen peroxide (H2O2), ferric reducing antioxidant power (FRAP), and ferric thiocyanate (FTC) methods. Among the selected plant extracts C. tora displayed the highest DPPH radical scavenging activity with an IC50 value 9.898 μg/mL, whereas A. sessilis had the maximum H2O2 scavenging activity with an IC50 value 16.25 μg/mL—very close to that of ascorbic acid (16.26 μg/mL). C. tora showed the highest absorbance in the FRAP assay and the lowest lipid peroxidation in the FTC assay. A methanol extract of A. sessilis resulted in the greatest phenolic content (292.65 ± 0.42 mg gallic acid equivalent (GAE)/g) measured by the Folin–Ciocalteu reagent method, while the smallest content was recorded for B. alba (72.66 ± 0.46 GAE/g). The greatest flavonoid content was observed with extracts of P. oleracea (39.38 ± 0.57 mg quercetin equivalents (QE)/g) as measured by an aluminium chloride colorimetric method, while the least was recorded for I. aquatica (6.61 ± 0.42 QE/g). There was a strong correlation between antioxidant activity with total phenolic (DPPH, R2 = 0.75; H2O2, R2 = 0.71) and total flavonoid content (DPPH, R2 = 0.84; H2O2, R2 = 0.66). This study demonstrates that these wild edible leafy plants could be a potential source of natural antioxidants

Enzymatic synthesis of epothilone A glycosides

Epothilones are extremely cytotoxic chemotherapeutic agents with epoxide, thiazole, and ketone groups that share equipotent kinetic similarity with taxol. The in vitro glycosylation catalyzed by uridine diphosphate glucosyltransferase (YjiC) from Bacillus licheniformis generated six novel epothilone A glycoside analouges including epothilone A 7-O-β-D-glucoside, epothilone A 7-O-β-D-galactoside, epothilone A 3,7-O-β-D-digalactoside, epothilone A 7-O-β-D-2-deoxyglucoside, epothilone A 7-O-β-L-rhamnoside, and epothilone A 7-O-β-L-fucoside. Epothilone A 7-O-β-D-glucoside was structurally elucidated by ultra-high performance liquid chromatography-photo diode array (UPLC-PDA) conjugated with high resolution quantitative time-of-flight-electrospray ionization mass spectroscopy (HR-QTOF ESI-MS/MS) supported by one-and two-dimensional nuclear magnetic resonance studies whereas other epothilone A glycosides were characterized by UPLC-PDA and HR-QTOF ESI-MS/MS analyses. The time dependent conversion study of epothilone A to epothilone A 7-O-β-D-glucoside found to be maximum (~26%) between 3 h to 5 h incubation