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The objective of this study is to evaluate and compare the quality of oils extracted from yellow and purple passion fruit seeds endemic to Northeast India. In this context, physicochemical properties (acid value, iodine value, etc), thermo physical analysis such as TGA and DSC was performed. Further, the antioxidant properties of seed oils were determined by TPC, TFC, DPPH and ABTS.+ analysis and their interrelation was analysed from Pearson correlation. Lower acid value (2–4.4 mg KOH g−1) and peroxide value (4.2–4.5 mg eq 1000 g−1) confirmed the good quality of oil. The thermal stability of different oils was found to be in the high range of 334.4 °C to 349.5 °C. Fatty acid composition of oils by GC analysis revealed abundance presence of approximately 70% of PUFA and the calculated oxidizability value suggested high oxidative stability in the oils. The universal oil quality score was observed to be high (>50%) when compared to other standard edible oil. Lowest radical inhibitory concentration was observed in yellow passion fruit seed oil from Manipur (70.7 ± 1.7 µg/ml in DPPH and 85.3 ± 5.5 µg/ml in ABTS). Profound antibacterial activity of oils was observed against K. Pneumonia (7.5 ± 0.35 to 12 ± 0.7 cm), B. Subtilis (5 ± 0.7 to 11 ± 0.7 cm), P. aeruginosa (2 to 11.5 ± 0.7 cm) and M. luteus (5 to 10 ± 0.7 cm). This work could add more information on uncommon passion fruit seed oil from Northeast India and further employ in various food and pharmaceutical sectors.

In this work, physicochemical properties and rheological behaviour of waste cooking oil (WCO), castor oil (CO), rubber seed oil (RSO) and their methyl esters (ME), as well as ME blends (5, 10 and 15 vol%) with diesel fuel were investigated. Rheological properties of samples were measured in the range of 25–80 °C temperature and 5–300 s−1 shear rate. Similarly, rheological behaviour of WCO, CO and RSO based methyl esters (WCOME, COME, ROSME) and its blends (5, 10, and 15 vol%) with diesel fuel were also studied. Power law model was used to study the flow behaviour of all the samples. The viscosity behaviour of oils (WCO, CO and RSO), methyl esters (WCOME, COME and RSOME) and their blends with diesel fuel showed Newtonian nature in the temperature range of 25–80 °C. The viscosity values of the chemically modified oil samples (via transesterification) were found to be lower than the original oil samples. However, WCO, CO and their methyl esters showed a slight deviation from Newtonian behaviour between shear rate intervals of 5–100 s−1. The dynamic viscosity of RSO (25.58 mPa.s) was less than that of WCO (49.91 mPa.s) and CO (338.08 mPa.s). At 40 °C, the kinematic viscosity values of RSOME (3.81 mm2/s) and WCOME (3.36 mm2/s) were lower than the value of COME (10.59 mm2/s). The dynamic viscosities of the samples were found to be dependent on fatty acids chain length, unsaturation and temperature. According to fatty acid composition and physicochemical properties of the oils samples, WCO, CO and RSO are suitable for substituting edible feedstock to make biodiesel production sustainable. The fuel properties of the methyl esters and their blends with diesel were estimated as per ASTM D6751 biodiesel standards.

Abstract Purpose Oleaginous yeasts can accumulate intracellular lipid bodies or triacylglycerides (TAGs) under nutrient limiting conditions. TAGs derived from those yeast strains are considered as an alternative to conventional plant-based oils for biodiesel production. In this study, we attempt to isolate and characterize yeast strains from selected traditional fermented foods of Manipur and Mizoram, India, and study their oleaginous attributes for biodiesel production. Method Fourteen potential oleaginous yeasts were isolated from fermented food samples of Manipur and Mizoram, India. The isolates were identified by 5.8S internal transcribed spacer (ITS) rRNA gene sequencing. Intracellular TAG accumulation by yeast cells were confirmed by Nile red fluorescence microscopy and spectrometry technique. The most promising isolates were evaluated for lipid accumulation having different initial carbon to nitrogen (C/N) ratios and also the full kinetic studies (depicting the glucose consumption, biomass, and lipid production) using optimum C/N ratio were estimated. Fatty acid methyl esters (FAME) profile of the transesterified lipids were analyzed by GC-MS. Results The identified yeast isolates belonged to seven different genera viz. Rhodotorula, Pichia, Candida, Saturnispora, Wickerhamomyces, Zygoascus, and Saccharomyces. Under nitrogen-limiting conditions, maximum biomass concentration of 5.66 ± 0.03 g/L and 4.713 ± 0.03 g/L was produced by Wickerhamomyces anomalus FK09 and Pichia kudriavzevii FK02, respectively. The highest lipid concentration (g lipid/L fermentation broth) of 0.58 g/L was attained by Rhodotorula mucilaginosa R2, followed by Wickerhamomyces anomalus FK09 (0.51 g/L), and Zygoascus hellenicus FC10 (0.41 g/L). Rhodotorula mucilaginosa R2 exhibited the maximum lipid content (% lipid/g dry cell weight) of (21.63 ± 0.1%) after 96 h of growth. The C/N ratio of 40 and 20 was found to be optimum for R. mucilaginosa R2 and W. anomalus FK09 with a lipid content of 22.21 ± 0.4% and 12.83 ± 0.08% respectively. Conclusion Newly isolated yeast strains were obtained from traditional fermented food samples of Manipur and Mizoram, India. FAME analysis of the transesterified lipid extracts suggested the potential use of yeast-derived oil as an alternative to vegetable oil for biodiesel production.

Employing sustainable techniques that utilize waste resources for the generation of valuable products are pivotal towards establishing economically-sound technologies. Moreover, directing these techniques towards creating entities that aid in alleviating environmental pollution concerns are highly desirable. Rice husks (RH) are abundantly available biomasses that are usually destroyed via inefficient means. Their utilization via thermochemical processes such as pyrolysis, yields fruitful, high-utility products like bio-char and bio-oil. Bio-char presents ideal platforms for developing highly-porous organic adsorbents. This work utilizes slow pyrolysis method for converting RH to bio-char under various temperatures in presence of a CO2 environment. Utilization of CO2 influences the textural and chemical nature of the developed bio-char and its deployment also lends an environmentally-conscious facet to this work, as it helps lower the overall carbon-footprint. As-prepared bio-char was activated in presence of an alkali that enhanced its overall surface area to 440 m2/g. Activated bio-char was utilized as an adsorbent for removal of commonly-found pharmaceutical pollutant, Ranitidine. Different parametric studies such as variation in pH, adsorbent dosage and pyrolysis temperature, were performed to understand their effect on adsorption capacity of prepared adsorbents. Adsorption of 50 ppm ranitidine on the activated bio-char at pH 9, resulted in the removal of 88.3% reactant, when 100 mg adsorbent dosage was provided. Activated bio-char displayed a maximum adsorption capacity of 65.8 mg/g under those conditions. Adsorption kinetics followed a pseudo-second order pathway while the adsorption isotherm could be described by the Langmuir model.

Application of ultrasound technology in modulating the hydration process during paddy germination was analyzed in this study. The effect of hydropriming (24 h) and sono-hydro priming (ultrasound priming, 12 h) on the hydration behaviour of paddies was determined at different temperatures (25–40 °C). Ultrasound pulse was applied for 10 min after every one hour for sono-hydro priming. Germination potential and microstructure analysis of treated paddies were also performed. Downward concave curve observed in hydration process of paddies indicates initial high-water absorption through diffusion process. Sono-hydro priming process showed higher hydration rate compared to hydropriming. The changes in moisture content during hydration processes fitted to theoretical (Fick's model) and empirical model (Peleg model) exhibited high regression coefficient (R2 > 0.95) indicating suitability for predicting hydration behaviour in both paddies for germination. The Peleg model adequately predicted saturation moisture content and sono-hydro priming efficiently increased the water absorption rate. Effective moisture diffusivity determined from Fick's diffusion model increased for sono-hydro priming. Activation energy estimated from effective moisture diffusivity required in sono-hydro priming (Ea = 20.32 and 19.19 KJ/mol respectively) for pigmented rice and non-pigmented rice was lower than hydropriming (Ea = 27.11 and 32.15 KJ/mol respectively). Both hydration processes were endothermic and non-spontaneous inferred from thermodynamic properties. Sono-hydro priming exhibited

In the present investigation, in-situ epoxidation of waste cooking oil and its methyl esters was prepared, and the rheological behavior was analyzed for biolubricant applications. Rheological properties of the prepared epoxides were measured at a temperature of 25–100 °C, at a shear rate ranging from 5 to 300 s−1. As viscosity is one of the critical parameters for potential biolubricant applications, in the present study, the power-law model was used to investigate the flow behavior of the epoxides. The viscosity of epoxidized waste cooking oil and its methyl ester epoxides showed Newtonian flow behavior in the studied temperature range. Different shear rates (5–100, 5–300, 100–300 s−1) were studied to determine the shear rate dependency of the epoxidized waste cooking oil and its methyl ester epoxides at different temperatures. From the average viscosity values, it was shown that the epoxides show identical results at all shear rates. The dynamic viscosities of the epoxidized waste cooking oil and its methyl ester epoxides were found to be dependent on fatty acid chain length, unsaturation, and temperature. Detailed physicochemical characterization for epoxide waste cooking oil (EWCO) and epoxide waste cooking oil methyl esters (EWCOME) were carried out to evaluate the properties for suitable biolubricant applications using standard American Society for Testing and Materials (ASTM) and American Oil Chemists’ Society (AOCS) methods. Based on the viscosity for EWCO (278.9 mm2/s) and EWCOME (12.15 mm2/s) and viscosity index for EWCO (164.94) and EWCOME (151.97) of the prepared epoxides, they could complement the standard ISO vegetable grade (VG) lubricants in the market.

The present work reports the formulation of castor oil (CO) epoxide as a bio-lubricant basestock. The main objective of this study was to improve the physico-chemical properties and thermo-oxidative stability of CO via structural modification. Epoxidation reaction was carried out at 60°C for 10 h using heterogeneous acidic ion-exchange resin (IR-120) as a catalysts (15mass%), acetic acid (0.5 mol) as an oxygen carrier and hydrogen peroxide (1.5 mol) as an oxygen donor. Product was confirmed by 1H-NMR, FTIR spectral analysis and epoxide content was determined by oxirane oxygen analysis. Further, significant physico-chemical properties such as viscosity, acid value (AV), pour point (PP) was determined for prepared CO epoxide. Thermo-oxidative stability of prepared epoxide and unmodified CO were compared by thermo gravimetric analysis (TGA) technique (in inert and oxygen atmospheres). Modified CO clearly illustrated significant improvement in the required physico-chemical properties and thermo-oxidative stability. Results of this study revealed that the prepared epoxide could be used as a potential bio-lubricant basestock in hydraulic lubricant application.

This work was aimed at investigating the effect of process parameters on dilute acid pretreatment and enzymatic hydrolysis of spent citronella biomass (after citronella oil extraction) and sugarcane bagasse on total reducing sugar (TRS) yield. In acid pretreatment, the parameters studied were acid concentration, temperature, and time. At the optimized condition (0.1 M H2SO4, 120°C, and 120 min), maximum TRS obtained was 452.27 mg·g−1 and 487.50 mg·g−1 for bagasse and citronella, respectively. Enzymatic hydrolysis of the pretreated biomass using Trichoderma reesei 26291 showed maximum TRS yield of 226.99 mg·g−1 for citronella and 282.85 mg·g−1 for bagasse at 10 FPU, 50°C, and 48 hr. The maximum crystallinity index (CI) of bagasse and citronella after acid pretreatment obtained from X-ray diffraction analysis was 64.41% and 56.18%, respectively. Decreased CI after enzymatic hydrolysis process to 37.28% and 34.16% for bagasse and citronella, respectively, revealed effective conversion of crystalline cellulose to glucose. SEM analysis of the untreated and treated biomass revealed significant hydrolysis of holocellulose and disruption of lignin.

The kinetics of the epoxidation of nonedible oil (mahua oil) by peroxyacetic acid, formed in situ by the reaction of aqueous hydrogen peroxide and acetic acid, in the presence of an acidic ion exchange resin (AIER) as the catalyst, was studied. The influence of some relevant process variables such as stirring speed, hydrogen peroxide to ethylenic unsaturation molar ratio, acetic acid to ethylenic unsaturation molar ratio, temperature, and catalytic loading of AIER on the epoxidation rate as well as on the oxirane ring stability and iodine value of the epoxidized Mahua oil (EMO) was examined. The proposed kinetic model takes into consideration two side reactions, namely, epoxy ring opening involving the formation of hydroxy acetate and a hydroxyl group and the reactions of the peroxyacid and epoxy group. Kinetic parameters were estimated by fitting experimental data using a nonlinear regression method. From the estimated kinetic constants, the apparent activation energy for the epoxidation reaction was found to be 12.0 kcal/mol. [ABSTRACT FROM AUTHOR]