TABLE 1.
Components of soil extracts prepared in three different waysa
| Ingredient | Amt (mg · liter−1) by soil extraction method |
||
|---|---|---|---|
| NSE | TSE1 | TSE2 | |
| Amino acids | |||
| Alanine | 0.47 | 0.10 | 0.18 |
| Glycine | 0.32 | 0.16 | 0.40 |
| Valine | 0.09 | ND | ND |
| Leucine | 0.47 | 0.05 | 0.06 |
| Isoleucine | 0.20 | 0.03 | 0.03 |
| Proline | 0.21 | 0.63 | 0.69 |
| γ-Aminobutric acid | 0.76 | 0.62 | 0.69 |
| Pipecolic acid | 0.09 | ND | ND |
| Pyroglutamic acid | 0.85 | 0.23 | 0.32 |
| Serine | 0.38 | ND | ND |
| Threonine | 1.38 | ND | ND |
| Phenylalanine | 0.22 | 0.03 | 0.04 |
| Cysteine | 0.22 | 0.12 | 0.29 |
| Aspartic acid | 0.27 | 0.08 | 0.31 |
| Glutamic acid | 0.55 | 0.40 | 0.39 |
| Asparagine | 0.57 | 0.41 | 0.52 |
| Ornithine | 0.77 | 0.46 | 0.45 |
| Glutamine | 0.55 | 0.67 | 0.66 |
| Lysine | 0.12 | 0.25 | 0.24 |
| Tyrosine | 9.29 | 0.10 | 0.09 |
| Tryptophane | 0.72 | 0.50 | 0.51 |
| Total | 18.50 | 4.84 | 5.87 |
| Fatty acids | |||
| Decanoic acid | 0.47 | ND | ND |
| Lauric acid | 0.48 | ND | ND |
| Myristoleic acid | 0.15 | ND | ND |
| Myristic acid | 1.18 | 0.07 | 0.08 |
| Isopentadecylic acid | 0.09 | ND | ND |
| Isopalmitic acid | 0.11 | ND | ND |
| Palmitoleic acid | 0.35 | 0.09 | 0.08 |
| Palmitic acid | 1.29 | 0.12 | 0.11 |
| Linoleic acid | 0.40 | ND | ND |
| Oleic acid | 0.40 | ND | ND |
| Stearic acid | 2.54 | 0.09 | 0.17 |
| Arachidic acid | 1.08 | 0.07 | 0.07 |
| Erucic acid | ND | 0.071 | 0.06 |
| Behenic acid | 1.80 | ND | ND |
| Nervonic acid | 0.07 | ND | ND |
| Lignoceric acid | 2.60 | 0.093 | 0.08 |
| Cerotic acid | 0.09 | 0.182 | 0.14 |
| Total | 13.10 | 0.79 | 0.79 |
| Organic acids | |||
| 3-Hydroxybutyric acid | 0.96 | 2.07 | 1.88 |
| Pyruvic acid | 0.40 | 4.31 | 5.75 |
| Acetoacetic acid | 1.47 | 28.75 | 27.25 |
| Lactic acid | 9.42 | ND | ND |
| Glycolic acid | 8.03 | ND | ND |
| 2-Hydroxybutyric acid | 0.09 | ND | ND |
| Malonic acid | 0.85 | 1.21 | 1.75 |
| Succinic acid | 1.43 | 2.18 | 1.78 |
| Fumaric acid | 0.05 | ND | ND |
| Oxaloacetic acid | 0.17 | 18.35 | 44.84 |
| α-Ketoglutaric acid | 0.11 | ND | ND |
| Malic acid | 0.73 | 3.32 | 3.33 |
| 2-Hydroxyglutaric acid | 0.50 | 0.93 | 0.72 |
| Cis-aconitic acid | 0.27 | 0.28 | 0.33 |
| Citric acid | 0.46 | 0.81 | 0.83 |
| Isocitric acid | 0.20 | 0.48 | 0.54 |
| Total | 25.14 | 62.69 | 89.00 |
| Inorganic compounds | |||
| Na+ | 58.87 | 83.65 | 85.05 |
| NH4+ | 6.93 | 17.76 | 19.45 |
| Mg2+ | 29.24 | 27.52 | 27.95 |
| K+ | 15.98 | 58.95 | 61.32 |
| Ca2+ | 87.93 | 114.59 | 119.49 |
| Cl− | 43.34 | 120.21 | 116.32 |
| NO3− | 489.67 | 398.43 | 384.51 |
| SO42− | 5.41 | 130.15 | 128.64 |
| PO42− | 10.66 | 4.74 | 4.18 |
| Total | 748.03 | 956.00 | 946.91 |
a
The NSE method was developed in this study; the TSE1 method involves autoclaving at 121°C for 1 h; the TSE2 method does not involve autoclaving. ND, not detected.