Fig. 1.
Fig. 2.
Validation results for determination coefficient (R2), matrix effect, limit of detection (LOD) and limit of quantification (LOQ) and uncertainty of analysed ergot alkaloids
| Linearity | Matrix effect (%) | LOD (μg kg−1) | LOQ (μg kg−1) | Uncertainty (%) (at concentration:) | ||||
|---|---|---|---|---|---|---|---|---|
| R2 | 10 μg kg−1 | 250 μg kg −1 | 1,000 μg kg −1 | |||||
| ergocristine | 0.9992 | y = 3.313x−14.6219 | 65.2 | 2.2 | 3.8 | 17.1 | 15.4 | 16.8 |
| ergocristinine | 0.9996 | y = 3.8130x−27.8254 | 97.1 | 1.0 | 2.0 | 24.9 | 4.5 | 7.3 |
| ergotamine | 0.9998 | y = 25522x−22.9181 | 132.8 | 2.2 | 4.6 | 30.6 | 16.2 | 11.6 |
| ergotaminine | 0.9998 | y = 8.3582x−45.1085 | 68.7 | 2.6 | 4.3 | 36.3 | 11.4 | 7.0 |
| ergocryptine | 0.9984 | y = 1.5186x−8.3205 | 85.4 | 2.1 | 5.0 | 20.9 | 10.3 | 12.9 |
| ergocryptinine | 0.9997 | y = 4.2522x−29.9617 | 94.1 | 1.6 | 3.5 | 26.3 | 4.9 | 10.0 |
| ergometrine | 0.9903 | y = 3.3136x−14.6219 | 42.3 | 2.5 | 4.7 | 32.9 | 22.8 | 23.9 |
| ergometrinine | 0.9902 | y = 3.6036x−12.6925 | 58.3 | 2.6 | 4.8 | 28.3 | 31.5 | 26.4 |
| ergosine | 0.9999 | y = 2.1023x−9.7773 | 81.5 | 1.7 | 4.1 | 20.8 | 9.7 | 10.2 |
| ergosinine | 0.9995 | y = 2.6077−16.4461 | 97.0 | 2.4 | 4.2 | 31.3 | 15.7 | 10.9 |
| ergocornine | 0.9996 | y = 3.3136x−14.6219 | 67.7 | 2.2 | 4.6 | 24.6 | 12.3 | 14.1 |
| ergocorninine | 0.9996 | y = 4.2199x−30.8679 | 99.9 | 0.8 | 1.8 | 24.4 | 5.7 | 11.0 |
Concentrations (μg kg−1) of ergot alkaloids determined in 16 positive compound feeds
| Sample No. | Err | Errine | Ert | Ertine | Erp | Erpine | Erm | Ermine | Ers | Ersine | Erc | Ercine | ∑ EAs |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | < LOQ | < LOQ | < LOQ | 23.2 | 23.2 | ||||||||
| 2 | < LOQ | 22.2 | < LOQ | 22.2 | |||||||||
| 3 | < LOQ | < LOQ | < LOQ | 15.5 | < LOQ | 15.5 | |||||||
| 4 | 16.4 | 15.7 | 32.1 | ||||||||||
| 5 | < LOQ | 24.4 | 24.4 | ||||||||||
| 6 | < LOQ | < LOQ | - | ||||||||||
| 7 | < LOQ | < LOQ | - | ||||||||||
| 8 | < LOQ | < LOQ | - | ||||||||||
| 9 | < LOQ | < LOQ | < LOQ | - | |||||||||
| 10 | 31.0 | 27.4 | 58.4 | ||||||||||
| 11 | < LOQ | 18.3 | 10.4 | 28.7 | |||||||||
| 12 | 38.3 | 24.0 | 62.3 | ||||||||||
| 13 | < LOQ | < LOQ | < LOQ | < LOQ | - | ||||||||
| 14 | < LOQ | < LOQ | < LOQ | < LOQ | - | ||||||||
| 15 | < LOQ | < LOQ | < LOQ | 11.9 | 11.9 | ||||||||
| 16 | < LOQ | 16.7 | 16.7 |
Validation results for recovery, repeatability and within-laboratory reproducibility
| Recovery (%) (at concentration:) | Repeatability (%) (at concentration:) | Reproducibility (%) (at concentration:) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| 10 μg kg−1 | 250 μg kg−1 | 1,000 μg kg 1 | 10 μg kg−1 | 250 μg kg−1 | 1,000 μg kg 1 | 10 μg kg−1 | 250 μg kg−1 | 1,000 μg kg 1 | |
| ergocristine | 102.8 | 94.5 | 95.8 | 3.7 | 7.9 | 9.2 | 8.1 | 5.4 | 7.3 |
| ergocristinine | 110.8 | 99.5 | 102.5 | 4.3 | 2.5 | 2.9 | 6.1 | 2.2 | 2.7 |
| ergotamine | 114.0 | 92.6 | 99.7 | 6.3 | 2.3 | 4.8 | 6.2 | 3.3 | 5.8 |
| ergotaminine | 117.8 | 96.2 | 102.4 | 1.2 | 3.9 | 1.4 | 3.4 | 4.2 | 2.5 |
| ergocryptine | 104.0 | 98.0 | 97.5 | 2.6 | 5.5 | 8.9 | 9.7 | 4.8 | 6.0 |
| ergocryptinine | 112.0 | 100.7 | 104.0 | 3.6 | 2.5 | 2.3 | 5.4 | 2.3 | 3.1 |
| ergometrine | 115.8 | 89.9 | 110.8 | 4.1 | 6.0 | 4.0 | 4.6 | 5.3 | 5.1 |
| ergometrinine | 111.9 | 85.2 | 112.6 | 3.3 | 4.3 | 4.7 | 7.7 | 5.5 | 4.0 |
| ergosine | 107.1 | 96.8 | 102.8 | 3.5 | 3.7 | 5.3 | 7.6 | 3.6 | 4.2 |
| ergosinine | 113.8 | 93.2 | 100.9 | 3.7 | 4.8 | 6.4 | 7.1 | 3.8 | 5.4 |
| ergocornine | 101.5 | 94.9 | 95.6 | 4.2 | 1.8 | 7.2 | 12.4 | 3.7 | 5.9 |
| ergocorninine | 110.2 | 99.6 | 104.5 | 3.9 | 3.2 | 1.9 | 6.7 | 2.8 | 3.1 |