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ThesisItem Open Access Process standardization for microwave and ultrasound assisted extraction of black cumin (Nigella Sativa L.) oil(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-07) Iftikhar Alam; Shahi, N.C.Black cumin (Nigella sativa L.) seed belong to Ranonculaceae family and has been cultivated for use in spices and traditional medicine system of Unani and Ayurveda and has a long history. The seed is known for its oil content but the best method of extraction is still the point of concern. Mechanical expression and solvent extraction are currently used commercially methods of oil extraction of black cumin oil but both of the methods have their shortcomings of less oil recovery, degradation of oil quality and more time consumption. The present research work was thus done to overcome these problems. In the present study, the standardization and optimization of microwave, ultrasound and their combined extraction methods were evaluated to enhance the oil recovery and the quality of extracted oil from black cumin. Experiment were planned using box Behnken design considering parameters of microwave power (320, 480 and 640 W), microwave time (3, 5 and 7 min) and solvent volume (100, 150 and 200 ml/sample) for MAE, ultrasound power (150, 200, 250 W), ultrasound time (15, 30 and 45 min) and solvent volume (100, 150 and 200 ml/sample) for UAE and for combination was done at the optimized value of MAE and UAE. Particle size of 1 mm and the solvent, hexane, were kept constant for all the experiments. As per the results obtained from MAE the oil recovery obtained ranged from 83.27 to 97.45 %, Specific gravity ranged from 0.9 to 0.81, Color ranged from 44.18 to 61.66, DPPH Antioxidant activity ranged from 32.21 to 70.38 %, Free fatty acid ranged from 6.12 to 7.22 % and Peroxide value ranged from 7.54 to 9.37 meq O2/kg. In UAE the oil recovery obtained ranged from 85.51 % to 94.80 % Specific gravity ranged from 0.73 to 0.89, Color ranged from 36.24 to 53.88, DPPH Antioxidant activity ranged from 25.50 to 78.18 %, Free fatty acid ranged from 5.83 to 6.92 % and Peroxide value ranged from 6.63 to 8.24 meq O2/kg. Optimization of these methods was done based on their respective responses by means of Response surface methodology using Design Expert 10.0.1.0 software. The optimized parameters of MAE for black cumin oil gave the maximum oil recovery of 92.26 %, specific gravity 0.81, color 43.11, antioxidant 67.29, FFA 6.46 % and PV of 8.15 at microwave power 320W, microwave time 5.5 min and solvent to solid ratio 10 ml/g. and the optimized parameters of UAE for black cumin oil gave the maximum oil recovery of 87.88 %, specific gravity 0.73, color 38.8, antioxidant 76.32, FFA 6.06 % and PV of 6.92 at ultrasound power 158.1 W, ultrasound time 25.2 min and solvent volume (100, 150 and 200 ml/sample). Combined study was conducted at the optimized condition of parameters from MAE and UAE methods. A single experiment was run at these parameters to find the results. The maximum oil recovery 91.12 %, specific gravity 0.84, color 44.28, antioxidant 58.46, FFA 6.51 % and PV of 8.37 were found at ultrasound power 158 W, ultrasound time 25.2 min and solvent volume 100ml/sample followed by microwave power 320 W, microwave time 5.5 min. Results showed that the microwave assisted extraction proved very effective approach for the extraction of black cumin oil for the better oil recovery and the best quality.ThesisItem Open Access An innovative approach for microbial production of pyruvate using agro-industrial waste(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Pant, Manish; Omre, P.K.Pyruvic acid (pyruvate) is a cellular metabolite found in the biochemical link between glycolysis and the tricarboxylic acid cycle. The microbial production of pyruvate from yeasts or bacteria is based on limiting the natural catabolism of pyruvate and limiting the accumulation of its many potential by-products. The industrial pyruvate production methodology involves the use of organic chemicals along with standardised protocol which increases the cost of the end product. In this process, pyruvic acid is distilled from a mixture of tartaric acid and potassium hydrogen sulphates at 220°C; the crude acid obtained is then distilled under vacuum. This process is simple to realize but not cost-effective. Hence, to realise a cheaper and efficient methodology alternative nutrient sources are explored. Development of media formulations is key in any bio-transformation involving micro-organisms. Establishment of optimal culture constraints and process development is considered crucial in this regard. Since, microbial enzyme activity is important to pyruvate accumulation in isolated strains, advances in pyruvate production can be achieved by media optimization. In this study, the media formulation involved various carbon sources viz. glycerol, rice straw and jackfruit rind with various proportions of nitrogen source, corn steep liquor (diluted with distilled water). The amount of nutrient sources is also very critical for formulation of standard media composition. Thus, the screening experiments were focused on standardizing the carbon and nitrogen levels for final experiments. In screening experiments, only incubation time and incubation temperature had significant effect on pyruvate production at a confidence level p<0.05. Finally, the factors compromised for main optimization experiments were screened as follows: carbon source 25%g/g, CSL 12%v/v, pH 5.0, agitation speed 220rpm, KH2PO4 1.1%g/g, thiamine 1.3%μg/g, biotin 1.4%μg/g, MgSO4.7H2O 0.3%g/g and CaCO3 43%g/g. The final experiments were based on full factorial design on different levels of independent variables. With glycerol as carbon source, the highest effect of CSL concentration on pyruvate concentration was observed and was highly significant (p<0.01) because it had high calculated F-value (519.60). The effect of temperature (340.32) followed by time (324.60) was also found significant (p<0.01). As per the results, the optimum solution was obtained when the CSL concentration was 0.992601, time was 0.509991, and temperature was 0.317417. Similarly with rice straw as carbon source, the highest effect of CSL concentration on pyruvate concentration was observed and was highly significant (p<0.01) because it had high calculated F-value (444.80). The effect of time (252.25) followed by temperature (143.40) was also found significant (p<0.01). As per the results, the optimum solution was obtained in terms of coded values when the CSL concentration was 0.999997, time was 0.882823, and temperature was 0.363031. Similarly with jackfruit rind as carbon source, the highest effect of CSL concentration on pyruvate concentration was observed and was highly significant (p<0.01) because it had high calculated F-value (1199.93). The effect of time (925.66) followed by temperature (255.70) was also found significant (p<0.01). As per the results, the optimum solution was obtained when the CSL concentration was 0.999986, time was 0.851276, and temperature was 0.438559. In supervised learning approach, the highest accuracy corresponds to 68.8889% for multilayer perceptron under 10X cross validation fold-maker, and the lowest is 0% for IBk. In fact, in this experimental comparison, we can say that multilayer perceptron was the best scheme in all applicable classifiers, with highest accuracy. Moreover, in unsupervised learning approach feature selection preprocessing was considered essential and principal component analysis was performed prior to each clustering algorithms application. The paired t-test analysis of the three carbon sources show a draw when compared with glycerol as a standard source. This sustains the fact that, organic replacements instead of conventional organic source i.e. glycerol can be utilized for pyruvate production with no random aberrations in pyruvate yield. The SEM results show that the diametric dimensions of the pyruvate produced from carbon sources were in the range of 30μm to 300 μm and is comparable with that of industrially produced sample.
