Lactic Acid Production from Cow Manure: Experimental Process Conditions Analysis
Abstract
:1. Introduction
2. Materials and Methods
2.1. Raw Material (Cow Manure)
2.2. Cow Manure Analysis
2.3. Microorganism
2.4. Process Flow
2.4.1. Experimental Design
2.4.2. Analysis of Monomeric Sugars, Lactic Acid, and Byproducts
2.5. Experimental Results Calculation
3. Results and Discussion
3.1. Results
3.2. Statistical Evaluation
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Independent Variables | Symbol | Range and Levels | ||||
---|---|---|---|---|---|---|
−α | −1 | 0 | 1 | +α | ||
Cow manure (g·L−1) | X1 | 46.36 | 60 | 80 | 100 | 113.63 |
Enzyme (IU·gCMDM−1) | X2 | 141.02 | 170 | 212.5 | 255 | 283.97 |
Temperature (°C) | X3 | 41.59 | 45 | 50 | 55 | 58.41 |
Run | Codified Variables | Experimental Levels | ||||
---|---|---|---|---|---|---|
X1 | X2 | X3 | Cow Manure (g·L−1) | Enzyme (IU·gCMDM−1) | Temperature (°C) | |
1 | 1 | −1 | −1 | 100 | 170 | 45 |
2 | 1 | 1 | 1 | 100 | 255 | 55 |
3 | 1 | −1 | 1 | 100 | 170 | 55 |
4 | 0 | 0 | 0 | 80 | 212.5 | 50 |
5 | 1.682 | 0 | 0 | 113.636 | 212.5 | 50 |
6 | −1 | 1 | 1 | 60 | 255 | 55 |
7 | 1 | 1 | −1 | 100 | 255 | 45 |
8 | −1 | −1 | 1 | 60 | 170 | 55 |
9 | −1 | −1 | −1 | 60 | 170 | 45 |
10 | −1.682 | 0 | 0 | 46.364 | 212.5 | 50 |
11 | −1 | 1 | −1 | 60 | 255 | 45 |
12 | 0 | 1.682 | 0 | 80 | 283.976 | 50 |
13 | 0 | 0 | 1.682 | 80 | 212.5 | 58.41 |
14 | 0 | 0 | 0 | 80 | 212.5 | 50 |
15 | 0 | −1.682 | 0 | 80 | 141.024 | 50 |
16 | 0 | 0 | 0 | 80 | 212.5 | 50 |
17 | 0 | 0 | 0 | 80 | 212.5 | 50 |
18 | 0 | 0 | −1.682 | 80 | 212.5 | 41.59 |
Sample | Hemicellulose (%) | Cellulose (%) | Lignin (%) | Ash (%) | Humidity (%) |
---|---|---|---|---|---|
Manure heap A * | 27.3 | 24.5 | 3.8 | 17.69 | 2.32 |
Manure heap B * | 26.3 | 25 | 3.8 | 18.85 | 2.5 |
Farm 1A | 28.3 | 23.4 | 3.5 | 18.04 | 2.32 |
Farm 1B | 30.2 | 21.7 | 3.1 | 17.43 | 2.11 |
Farm 2A | 28.4 | 23.6 | 4.1 | 17.13 | 2.76 |
Farm 2B | 28.3 | 22.9 | 5.3 | 16.5 | 2.23 |
Average | 28.1 | 23.5 | 3.9 | 17.6 | 2.4 |
Cow Manure (g/L) | Mannose % | Glucose % | Galactose % | Arabinose % | Xylose % | Total % | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
46.4 | 0.08 | 10.09 | 6.36 | 18.63 | 48.30 | 44.56 | ||||||||||||
60 | 0.06 | 4.32 | - | 4.39 | 3.02 | - | 3.44 | 10.66 | - | 11.14 | 22.75 | - | 25.06 | 22.36 | - | 23.10 | ||
80 | 0.04 | - | 0.53 | 5.85 | - | 52.89 | 3.55 | - | 6.40 | 8.84 | - | 15.68 | 26.35 | - | 31.77 | 25.53 | - | 47.19 |
100 | 0.04 | - | 0.32 | 8.93 | - | 47.84 | 4.23 | - | 4.48 | 9.53 | - | 10.34 | 28.58 | - | 31.10 | 29.12 | - | 45.00 |
113.6 | 0.22 | 8.34 | 4.50 | 11.04 | 28.62 | 27.98 |
Run | Mannose (g·L−1) | Glucose (g·L−1) | Galactose (g·L−1) | Arabinose (g·L−1) | Xylose (g·L−1) | Total (g·L−1) |
---|---|---|---|---|---|---|
1 | 0.48 | 21.23 | 1.35 | 2.82 | 11.59 | 32.47 |
2 | 0.61 | 40.53 | 2.09 | 3.4 | 11.68 | 53.31 |
3 | 0.29 | 24.76 | 1.37 | 2.36 | 8.23 | 32.01 |
4 | 0.31 | 12.9 | 2.32 | 2.2 | 9.7 | 22.43 |
5 | 0.55 | 29.07 | 3.91 | 3.4 | 11.64 | 43.57 |
6 | 0.31 | 15.86 | 0.75 | 1.9 | 6.96 | 20.78 |
7 | 0.45 | 20.81 | 1.13 | 2.34 | 9.65 | 29.38 |
8 | 0.19 | 12.89 | 0.55 | 1.49 | 5.79 | 15.91 |
9 | 0.21 | 15.29 | 0.11 | 1.52 | 6.77 | 18.9 |
10 | 0.2 | 7.21 | 1.13 | 1.52 | 5.91 | 10.97 |
11 | 0.21 | 17.25 | 0.12 | 0.93 | 9.15 | 22.66 |
12 | 0.42 | 18.37 | 3.21 | 2.41 | 9.33 | 28.74 |
13 | 0.27 | 24.66 | 1.33 | 2.45 | 8.07 | 31.78 |
14 | 0.29 | 12.43 | 2.33 | 2.14 | 8.53 | 20.72 |
15 | 0.41 | 25.26 | 2.98 | 2.71 | 10.15 | 36.51 |
16 | 0.48 | 27.15 | 1.29 | 2.88 | 11.16 | 37.96 |
17 | 0.37 | 18.15 | 1.11 | 2.1 | 8.44 | 25.17 |
18 | 0.23 | 14.6 | 0.94 | 2.0 | 8.15 | 20.92 |
Run | Acetic acid (g·L−1) | Furfural (g·L−1) | 5-HMF (g·L−1) | Acetic Acid (g·L−1) |
---|---|---|---|---|
Chemical Pretreatment | SSAF | |||
1 | 1.44 | 0.74 | 0.94 | 1.80 |
2 | 2.00 | 1.26 | 5.00 | 2.20 |
3 | 2.00 | 1.26 | 5.00 | 1.72 |
4 | 0.96 | 1.43 | 0.33 | 1.08 |
5 | 2.14 | 1.14 | 1.38 | 1.90 |
6 | 0.58 | 0.42 | 0.48 | 0.90 |
7 | 1.44 | 0.74 | 0.94 | 1.80 |
8 | 0.58 | 0.42 | 0.48 | 0.96 |
9 | 0.62 | 0.80 | 0.38 | 1.24 |
10 | 0.81 | 1.00 | 0.33 | 0.81 |
11 | 0.62 | 0.80 | 0.38 | 1.00 |
12 | 2.14 | 1.14 | 1.38 | 1.05 |
13 | 1.36 | 0.74 | 0.54 | 1.38 |
14 | 0.96 | 1.43 | 0.33 | 1.20 |
15 | 0.94 | 0.68 | 0.61 | 1.70 |
16 | 1.04 | 0.76 | 3.92 | 2.00 |
17 | 1.14 | |||
18 | 1.36 | 0.74 | 0.54 | 1.92 |
Average | 1.33 | 1.04 | 1.35 | 1.45 |
Run | 24 h | 48 h | ||||
---|---|---|---|---|---|---|
LA (g·L−1) | Productivity (g·L−1·h−1) | Yield wt.% (LA/Lignocellulosic) | LA (g·L−1) | Productivity (g·L−1·h−1) | Yield wt.% (LA/ Lignocellulosic) | |
1 | 3.21 | 0.13 | 6.22 | 15.06 | 0.31 | 29.19 |
2 | 2.04 | 0.09 | 3.95 | 2.52 | 0.05 | 4.88 |
3 | 1.89 | 0.08 | 3.66 | 2.16 | 0.05 | 4.19 |
4 | 12.45 | 0.52 | 30.16 | 13.2 | 0.28 | 31.98 |
5 | 2.13 | 0.09 | 3.63 | 2.43 | 0.05 | 4.14 |
6 | 6.36 | 0.27 | 20.54 | 11.82 | 0.25 | 38.18 |
7 | 5.34 | 0.22 | 10.35 | 14.34 | 0.30 | 27.79 |
8 | 4.80 | 0.20 | 15.50 | 7.38 | 0.15 | 23.84 |
9 | 11.10 | 0.46 | 35.85 | 14.31 | 0.30 | 46.22 |
10 | 9.18 | 0.38 | 38.37 | 11.94 | 0.25 | 49.91 |
11 | 11.55 | 0.48 | 37.31 | 12.51 | 0.26 | 40.41 |
12 | 11.01 | 0.46 | 26.67 | 12.9 | 0.27 | 31.25 |
13 | 1.83 | 0.08 | 4.43 | 2.01 | 0.04 | 4.87 |
14 | 11.13 | 0.46 | 26.96 | 12.06 | 0.25 | 29.22 |
15 | 9.90 | 0.41 | 23.98 | 10.44 | 0.22 | 25.29 |
16 | 13.65 | 0.57 | 33.07 | 15.09 | 0.31 | 36.56 |
17 | 11.13 | 0.46 | 26.96 | 12.45 | 0.26 | 30.16 |
18 | 13.41 | 0.56 | 32.49 | 13.65 | 0.28 | 33.07 |
Time | Model | Intercept | Cow Manure Content (CM) | Enzyme E | Temperature (T) | CM:T | CM2 | E2 | T2 | Adjusted R2 | p-Value |
---|---|---|---|---|---|---|---|---|---|---|---|
24 h | LA | −2.2024 × 102 | -- | -- | 7.4187 | -- | −6.6988 × 10−3 | −5.4426 10−4 | −7.9398 × 10−2 | 0.8537 | <0.0001 |
Y | −2.5511 × 102 | −2.3562 | 5.7394 × 10−1 | 1.4827 | 3.5200 | -- | −1.2879 10−3 | −1.9009 × 10−1 | 0.8647 | <0.0001 | |
P | −5.5552 | 1.8012 × 10−2 | -- | 2.4129 × 10−1 | 3.6250 × 10−4 | −2.5738 × 10−4 | -- | −2.9163 × 10−3 | 0.818 | <0.0001 | |
48 h | LA | −2.0978 × 102 | 1.6774 | 7.1460 | -- | −2.1375 × 10−2 | −4.4435 × 10−3 | -- | −6.1962 × 10−2 | 0.8755 | <0.0001 |
Y | −320.523 | 0.87509 | -- | 15.3092 | −0.02912 | -- | -- | −0.14735 | 0.9039 | <0.0001 | |
P | −4.3588 | 3.4893 × 10−2 | -- | 1.4845 × 10−1 | −4.4500 × 10−4 | −9.2354 × 10−5 | -- | −1.2865 × 10−3 | 0.8745 | <0.0001 |
Process Time (h) | Cow Manure (g·L−1) | Enzyme (IU·gCM DM−1) | Temperature (°C) | Lactic Acid (g·L−1) | Productivity (g·L−1·h−1) | Yield (wt. %) | Desirability |
---|---|---|---|---|---|---|---|
24 h | 71 | 220 | 45 | 13.4 | 0.53 | 36.28 | 0.952 |
48 h | 86 | 140 | 42.5 | 15.27 | 0.317 | 32.76 | 0.917 |
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Garrido, R.; Falguera, V.; Pérez Navarro, O.; Acosta Solares, A.; Cabeza, L.F. Lactic Acid Production from Cow Manure: Experimental Process Conditions Analysis. Fermentation 2023, 9, 604. https://doi.org/10.3390/fermentation9070604
Garrido R, Falguera V, Pérez Navarro O, Acosta Solares A, Cabeza LF. Lactic Acid Production from Cow Manure: Experimental Process Conditions Analysis. Fermentation. 2023; 9(7):604. https://doi.org/10.3390/fermentation9070604
Chicago/Turabian StyleGarrido, Ricard, Víctor Falguera, Omar Pérez Navarro, Amanda Acosta Solares, and Luisa F. Cabeza. 2023. "Lactic Acid Production from Cow Manure: Experimental Process Conditions Analysis" Fermentation 9, no. 7: 604. https://doi.org/10.3390/fermentation9070604