13 20 50 60 4Molecular sieve content material(g/L)Figure 9 Effect of molecular sieves on lipase catalyzed synthesis of D-isoascorbyl palmitate. (Enzyme load 15 (weight of substrates); time: 24 h; molar ratio: 1:6; acetone 20 mL; temperature: 50 ; speed: 200 rpm)Sun et al. Chemistry Central Journal 2013, 7:114 http://journal.chemistrycentral/content/7/1/Page 9 ofreliability. The regression coefficients, together with the corresponding P-values, for the model in the conversion rate of isoascorbyl palmitate, have been presented in Table 5. The P-values are applied as a tool to verify the significance of every coefficient, which also indicate the interaction strength amongst every independent variable. The smaller sized the P values, the larger the significance of your corresponding coefficient [40]. Table five showed that the quadratic model was highly substantial (p0.01). Meanwhile the lack-of-fit the P values of 0.0027 indicated that the lack of fit was substantial. Enzyme load and molar ratio of D-isoascorbic to palmitic acid had a hugely linear effect at 1 level. Temperature was also considerable at 5 level. While the interaction effects of independent variables have been discovered no substantial quadratic impact (p-value: AB=0.2665, BC=0.4343). Using the created experimental information (Table 3), the polynomial model for conversion price ( ) Y conversion price was regressed by only thinking about the considerable terms and was shown as under: Y conversion price ?84:66 ?16:90X 1 ?5:05X two ?eight:16X 3 -7:15X 1 X three -1:94X two X three -4:88X 1 two -10:79X 3Table 5 Final results of ANOVA analysis of a complete second-order polynomial model for reaction conditions for the production of D- isoascorbyl palmitateSource Model A B C AB AC BC A2 B2 C2 Residual Lack of match Pure error Cor total R-squared Sum of squares 3798.88 2285.56 203.11 533.17 32.43 204.35 14.98 87.99 63.87 429.81 103.73 103.55 0.18 3902.61 = 0.9734 df 9 1 1 1 1 1 1 1 1 1 5 three two 14 Adj-Squared = 0.9256 C.V. = six.15 Coefficient estimate 422.ten 2285.56 203.11 533.17 32.43 204.35 14.98 87.99 63.87 429.81 20.75 34.52 0.092 374.63 0.0027** F-Value 20.35 110.17 9.79 25.70 1.56 9.85 0.72 4.24 3.08 20.72 P-Value 0.0020** 0.0001** 0.0260* 0.0039** 0.2665 0.0257* 0.4343 0.0945* 0.1397 0.0061**??** Important at 1 level * Considerable at 5 level Adeq Precision=15.9.Where Y is the response variable (isoascorbyl palmitate conversion price, ), and X1, X2 and X3 are enzyme load, temperature and molar ratio of D-isoascorbic to palmitic acid, respectively. Figure 10 shows the observed and predicted conversion price determined by the modelTable 4 Experimental styles plus the benefits of Box-Behnken design for optimizing reaction situations for the production of D- isoascorbyl palmitateRuns A 1 two three four 5 6 7 eight 9 10 11 12 13 14 15 1(20) 0(13) -1(5) -1(five) 0(13) 1(20) 1(20) 0(13) 0(13) -1(five) 0(13) -1(five) 1(20) 0(13) 0(13) Coded levels B -1(40) 1(60) 1(60) 0(50) 0(50) 0(50) 0(50) -1(40) 1(60) 0(50) -1(40) -1(40) 1(60) 0(50) 0(50) C 0(four) 1(six) 0(4) 1(two) 0(four) -1(2) 1(six) -1(2) -1(2) -1(2) 1(six) 0(4) 0(4) 0(4) 0(four) I 92.16-Aminohexadecanoic acid site 70 84.Buy368866-07-3 78 62.PMID:24275718 69 65.89 84.03 86.89 85.78 50.00 70.98 37.08 72.88 53.89 90.22 83.97 85.02 Conversion rate ( ) II 93.86 85.74 64.63 66.25 84.75 85.53 87.46 50.60 71.38 37.06 71.36 55.75 91.24 86.01 84.20 Typical 93.28 ?0.82 85.26 ?0.68 63.66 ?1.37 66.07 ?0.25 84.39 ?0.51 86.21 ?0.96 86.62 ?1.19 50.30 ?0.42 71.18 ?0.28 37.07 ?0.01 72.12 ?1.07 54.82 ?1.32 90.73 ?0.72 84.99 ?1.44 84.61 ?0.58 Predicted 90.33 80.98 66.61 67.40 84.66 84.88 86.91 54.58 68.53 36.78 74.78 50.8.