The Effects of Nitrogen Application and Varietal Variation on the Product Quality and In Vitro Bioaccessibility of Bioactive Compounds of Baby Spinach Varieties Grown in a Soilless Growth Medium
Abstract
:1. Introduction
2. Materials and Methods
2.1. Chemicals
2.2. Experimental Site, Crop Establishment and Application of N Treatments
2.3. Leaf Fresh Weight, Colour and Chlorophyll Content
2.4. In Vitro Digestion
2.5. Extraction of Phenolic Compounds
2.6. Total Phenolic Content (TPC)
2.7. Quantification of Phenolic Compounds
2.8. Ferric Reducing Antioxidant Power (FRAP)
2.9. 2,2-Azino-bis-3-ethylbenzothiazoline-6-sulfonic (ABTS) Scavenging Activity
2.10. 2,2-diphenyl-1-picrylhydrazyl (DPPH) Radical Scavenging Activity
2.11. Carotenoids
2.12. Data Analysis
3. Results and Discussion
3.1. Effect of Varietal Response and N Supply Levels on Leaf Fresh Weight
3.2. Effect of Varietal Response and N Supply Levels on Colour
3.3. Effect of Varietal Response and N Supply Levels on Chlorophyll Content
3.4. Effect of Varietal Response and N Supply Levels on Bioactive Compounds and Their Bioaccessibility
3.4.1. Phenols
3.4.2. Carotenoids
3.4.3. Varietal Variation and Nitrogen Application on the Antioxidant Activity and Bioaccessibility
3.4.4. Multivariate Analysis
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Cultivar | Nitrogen Level (mg/L) | Undigested | Intestinal Fraction (IF) | Bioaccessibility (%) |
---|---|---|---|---|
TPC (mg/g) | ||||
‘Acadia’ | 0 | 7.34 ± 0.15 h | 3.84 ± 0.24 de | 52.27 ± 3.32 cdef |
30 | 7.77 ± 0.12 fg | 4.12 ± 0.63 cde | 52.99 ± 8.08 cdef | |
60 | 8.33 ± 0.26 bc | 3.534 ± 0.254 def | 42.41 ± 3.04 fg | |
90 | 8.09 ± 0.03 de | 3.713 ± 0.379 de | 45.88 ± 4.68 efg | |
120 | 7.94 ± 0.13 defg | 4.289 ± 0.561 bcd | 54.01 ± 7.06 bcdef | |
150 | 7.72 ± 0.032 g | 4.610 ± 0.447 bcd | 59.74 ± 5.79 bcde | |
‘Crosstrek’ | 0 | 7.30 ± 0.03 h | 3.062 ± 0.241 ef | 41.92 ± 3.29 fg |
30 | 7.83 ± 0.09 fg | 3.845 ± 0.611 de | 49.10 ± 7.81 def | |
60 | 8.45 ± 0.23 ab | 5.355 ± 0.377 ab | 63.39 ± 4.46 bcd | |
90 | 7.48 ± 0.20 h | 3.823 ± 0.057 de | 51.09 ± 0.77 cdef | |
120 | 7.72 ± 0.09 g | 5.270 ± 0.297 abc | 68.29 ± 3.85 b | |
150 | 7.72 ± 0.02 g | 6.412 ± 0.075 a | 83.09 ± 0.98 a | |
‘Traverse’ | 0 | 7.81 ± 0.17 fg | 2.471 ± 0.356 f | 31.64 ± 4.56 g |
30 | 8.02 ± 0.10 def | 3.521 ± 0.462 def | 43.92 ± 5.76 fg | |
60 | 8.62 ± 0.09 a | 4.591 ± 0.156 bcd | 53.29 ± 1.81 cdef | |
90 | 8.17 ± 0.03 bc | 3.901 ± 0.173 de | 47.76 ± 2.12 ef | |
120 | 8.11 ± 0.06 cde | 3.954 ± 0.083 de | 48.75 ± 1.03 def | |
150 | 7.92 ± 0.03 efg | 5.196 ± 0.581 bc | 65.58 ± 7.33 bc | |
p-coumaric (µg/g) | ||||
‘Acadia’ | 0 | 293.4 ± 1.24 a | 4.05 ± 0.02 d | 1.38 ± 0.01 i |
30 | 217.2 ± 1.02 c | 2.95 ± 0.03 defg | 1.36 ± 0.01 i | |
60 | 152.2 ± 0.67 g | 3.70 ± 0.81 de | 2.43 ± 0.53 ghi | |
90 | 164.5 ± 0.84 f | 6.70 ± 0.02 c | 4.08 ± 0.01 de | |
120 | 55.9 ± 0.23 o | 1.86 ± 0.04 gh | 3.33 ± 0.06 efg | |
150 | 87.5 ± 0.43 j | 1.23 ± 0.02 h | 1.40 ± 0.03 i | |
‘Crosstrek’ | 0 | 230.1 ± 0.48 b | 3.03 ± 0.02 def | 1.32 ± 0.01 i |
30 | 215.8 ± 0.73 d | 5.63 ± 0.30 c | 2.61 ± 0.14 fgh | |
60 | 61.6 ± 1.07 n | 2.90 ± 0.02 efg | 4.72 ± 0.03 cd | |
90 | 184.2 ± 0.20 e | 9.92 ± 0.02 a | 5.39 ± 0.01 c | |
120 | 54.8 ± 0.93 o | 2.87 ± 0.46 efg | 5.24 ± 0.84 c | |
150 | 75.4 ± 0.1.71 l | 2.08 ± 0.02 fgh | 2.76 ± 0.02 fgh | |
‘Traverse’ | 0 | 107.1 ± 0.27 i | 3.84 ± 0.91 de | 3.59 ± 0.85 def |
30 | 119.2 ± 0.05 h | 10.43 ± 0.01 a | 8.75 ± 0.01 a | |
60 | 86.8 ± 0.14 j | 8.23 ± 0.58 b | 9.48 ± 0.67 a | |
90 | 75.0 ± 0.20 l | 5.35 ± 0.06 c | 7.13 ± 0.08 b | |
120 | 81.9 ± 0.71 k | 1.74 ± 0.49 h | 2.13 ± 0.60 hi | |
150 | 66.3 ± 0.62 m | 1.15 ± 0.01 h | 1.73 ± 0.01 hi | |
Quercetin (µg/g) | ||||
‘Acadia’ | 0 | 5687 ± 3.5 e | 21.05 ± 0.73 cd | 0.37 ± 0.01 g |
30 | 4454 ± 1.4 f | 19.87 ± 0.09 cd | 0.45 ± 0.00 g | |
60 | 3950 ± 8.5 g | 23.47 ± 1.26 c | 0.59 ± 0.03 g | |
90 | 3340 ± 0.7 h | 22.86 ± 0.20 c | 0.68 ± 0.01 g | |
120 | 477 ± 0.7 l | 2.36 ± 3.11 e | 0.49 ± 0.65 g | |
150 | 297 ± 1.7 n | 12.67 ± 0.09 cde | 4.27 ± 0.03 e | |
‘Crosstrek’ | 0 | 6931 ± 7.9 a | 17.59 ± 0.35 cd | 0.25 ± 0.00 g |
30 | 6666 ± 0.3 b | 9.56 ± 0.42 de | 0.14 ± 0.01 g | |
60 | 5705 ± 4.1 d | 21.02 ± 0.15 cd | 0.37 ± 0.00 ef | |
90 | 428 ± 7.5 m | 11.96 ± 0.15 cde | 2.79 ± 0.03 f | |
120 | 204 ± 3.5 q | 12.23 ± 0.31 cde | 5.99 ± 0.15 d | |
150 | 261 ± 1.4 o | 12.39 ± 0.08 cde | 4.75 ± 0.03 e | |
‘Traverse’ | 0 | 6621 ± 2.0 c | 15.02 ± 2.47 cde | 0.23 ± 0.04 g |
30 | 574 ± 0.7 j | 60.22 ± 0.43 a | 10.49 ± 0.07 a | |
60 | 531 ± 0.71 k | 46.37 ± 17.41 b | 8.73 ± 3.28 b | |
90 | 596 ± 0.9 i | 49.41 ± 2.89 b | 8.29 ± 0.48 b | |
120 | 227 ± 1.6 p | 15.40 ± 0.49 cde | 6.78 ± 0.21 c | |
150 | 474 ± 0.1 j | 14.68 ± 0.27 cde | 3.10 ± 0.06 f | |
Ferulic acid (µg/g) | ||||
‘Acadia’ | 0 | 6908 ± 9.2 a | 37.93 ± 0.42 e | 0.55 ± 0.01 f |
30 | 6592 ± 6.0 b | 72.53 ± 0.54 cd | 1.10 ± 0.01 defg | |
60 | 6232 ± 0.4 c | 65.88 ± 2.09 de | 1.06 ± 0.03 efg | |
90 | 5576 ± 4.6 g | 58.11 ± 0.30 de | 1.04 ± 0.00 fg | |
120 | 3732 ± 4.4 o | 64.93 ± 0.67 de | 1.74 ± 0.02 bcdef | |
150 | 4558 ± 9.3 l | 65.37 ± 0.11 de | 1.43 ± 0.00 cdef | |
‘Crosstrek’ | 0 | 5352 ± 8.8 h | 112.22 ± 0.61 ab | 2.10 ± 0.01 abc |
30 | 5818 ± 7.0 f | 122.81 ± 5.09 a | 2.11 ± 0.09 abc | |
60 | 6020 ± 2.9 d | 113.64 ± 56 ab | 1.89 ± 0.01 bcdef | |
90 | 5845 ± 8.6 e | 84.90 ± 0.73 bcd | 1.45 ± 0.01 bcdef | |
120 | 4999 ± 7.4 j | 89.00 ± 12.10 bcd | 1.78 ± 0.24 bcdef | |
150 | 4173 ± 1.9 n | 71.68 ± 0.84 cd | 1.72 ± 0.02 bcdef | |
‘Traverse’ | 0 | 3566 ± 3.7 p | 105.77 ± 42.02 ab | 2.97 ± 1.18 a |
30 | 5062 ± 4.8 i | 97.99 ± 0.73 abc | 1.94 ± 0.01 bcd | |
60 | 4516 ± 4.6 m | 104.62 ± 4.68 ab | 2.32 ± 0.10 ab | |
90 | 4513 ± 1.2 m | 86.85 ± 0.48 bcd | 1.92 ± 0.01 bcde | |
120 | 4930 ± 0.1 k | 65.65 ± 0.96 de | 1.33 ± 0.02 cdefg | |
150 | 3328 ± 1.8 q | 61.59 ± 0.24 de | 1.85 ± 0.01 bcdef | |
Kaempferol (µg/g) | ||||
‘Acadia’ | 0 | 211.6 ± 0.09 a | 7.55 ± 0.24 c | 3.57 ± 0.11 b |
30 | 142.4 ± 0.18 f | 4.91 ± 0.03 c | 3.45 ± 0.02 b | |
60 | 149.7 ± 0.83 e | 9.83 ± 0.15 bc | 6.56 ± 0.10 b | |
90 | 149.8 ± 0.66 e | 3.60 ± 0.03 c | 2.41 ± 0.02 b | |
120 | 127.3 ± 1.14 g | 3.40 ± 0.02 c | 2.67 ± 0.01 b | |
150 | 190.3 ± 0.24 c | 4.33 ± 0.04 c | 2.28 ± 0.02 b | |
‘Crosstrek’ | 0 | 74.0 ± 0.90 q | 1.80 ± 0.01 c | 2.44 ± 0.01 b |
30 | 83.6 ± 0.53 o | 4.65 ± 0.22 c | 5.56 ± 0.27 b | |
60 | 86.6 ± 0.02 n | 6.68 ± 0.09 c | 7.72 ± 0.11 b | |
90 | 98.2 ± 0.38 l | 3.80 ± 0.03 c | 3.86 ± 0.03 b | |
120 | 119.4 ± 0.42 h | 4.96 ± 0.69 c | 4.16 ± 0.58 b | |
150 | 116.7 ± 0.82 i | 4.91 ± 0.06 c | 4.21 ± 0.05 b | |
‘Traverse’ | 0 | 78.1 ± 0.14 p | 1.13 ± 0.04 c | 1.45 ± 0.05 b |
30 | 108.2 ± 0.03 k | 25.86 ± 0.21 a | 23.90 ± 0.19 a | |
60 | 97.0 ± 0.53 m | 18.06 ± 12.91 ab | 18.62 ± 13.30 a | |
90 | 110.2 ± 0.38 j | 3.38 ± 0.05 c | 3.07 ± 0.05 b | |
120 | 195.9 ± 0.28 b | 4.52 ± 0.01 c | 2.30 ± 0.01 b | |
150 | 158.1 ± 0.12 d | 2.53 ± 0.02 c | 1.60 ± 0.01 b |
Cultivar | Nitrogen Level (mg/L) | Undigested | Intestinal | Bioaccessibility (%) |
---|---|---|---|---|
TCC (mg/g) | ||||
‘Acadia’ | 0 | 0.59 ± 0.00 hi | 0.14 ± 0.02 l | 23.90 ± 3.03 i |
30 | 0.58 ± 0.01 i | 0.22 ± 0.01 k | 38.53 ± 1.48 h | |
60 | 0.63 ± 0.00 f | 0.59 ± 0.00 c | 93.60 ± 0.58 b | |
90 | 0.76 ± 0.00 b | 0.41 ± 0.00 g | 53.73 ± 0.25 g | |
120 | 0.78 ± 0.01 a | 0.58 ± 0.00 c | 74.65 ± 0.23 c | |
150 | 0.75 ± 0.00 b | 0.74 ± 0.01 a | 97.56 ± 0.77 a | |
‘Crosstrek’ | 0 | 0.52 ± 0.02 k | 0.02 ± 0.00 p | 4.04 ± 0.73 m |
30 | 0.55 ± 0.00 j | 0.05 ± 0.00 o | 9.64 ± 0.22 l | |
60 | 0.60 ± 0.00 gh | 0.08 ± 0.00 n | 12.98 ± 0.21 k | |
90 | 0.61 ± 0.00 g | 0.34 ± 0.00 i | 55.30 ± 0.57 fg | |
120 | 0.68 ± 0.01 de | 0.38 ± 0.00 h | 55.78 ± 0.18 f | |
150 | 0.70 ± 0.00 d | 0.68 ± 0.01 b | 97.38 ± 1.18 a | |
‘Traverse’ | 0 | 0.52 ± 0.01 k | 0.02 ± 0.00 p | 3.87 ± 0.25 m |
30 | 0.58 ± 0.00 i | 0.13 ± 0.00 m | 22.32 ± 0.29 j | |
60 | 0.59 ± 0.01 hi | 0.32 ± 0.00 j | 53.98 ± 0.39 g | |
90 | 0.64 ± 0.00 f | 0.42 ± 0.01 f | 66.54 ± 1.23 e | |
120 | 0.67 ± 0.01 e | 0.44 ± 0.01 e | 65.22 ± 0.96 e | |
150 | 0.74 ± 0.02 c | 0.54 ± 0.00 d | 72.86 ± 0.63 d | |
LSD 0.05 | 0.01546 | 0.007963 | 1.648 | |
CV% | 1.5 | 1.4 | 2.0 | |
Lutein (µg/g) | ||||
‘Acadia’ | 0 | 4224 ± 2 o | 725.45 ± 0.71 m | 17.17 ± 0.02 b |
30 | 7388 ± 8 l | 1274.17 ± 8.77 k | 17.25 ± 0.12 b | |
60 | 14,143 ± 9 k | 2835.45 ± 26.03 e | 20.05 ± 0.18 a | |
90 | 41,421 ± 10 e | 1960.91 ± 17.36 i | 4.73 ± 0.04 m | |
120 | 48,957 ± 5 d | 3249.75 ± 22.08 d | 6.64 ± 0.04 k | |
150 | 68,180 ± 16 a | 4602 ± 5.61 a | 9.55 ± 0.37 f | |
‘Crosstrek’ | 0 | 3475 ± 4 q | 344.42 ± 2.44 p | 9.91 ± 0.07 e |
30 | 3578 ± 6 p | 466.77 ± 1.91 o | 13.04 ± 0.05 d | |
60 | 25,380 ± 3 i | 601.83 ± 5.66 n | 2.37 ± 0.02 n | |
90 | 27,409 ± 0 h | 1992.74 ± 23.82 i | 7.27 ± 0.09 j | |
120 | 29,355 ± 6 g | 2653.77 ± 254.76 f | 9.03 ± 0.87 g | |
150 | 67,409 ± 8 b | 4509.80 ± 49.76 b | 6.69 ± 0.07 k | |
‘Traverse’ | 0 | 4446 ± 5 n | 326.73 ± 3.69 p | 7.35 ± 0.08 ij |
30 | 5482 ± 1 m | 880.01 ± 3.60 l | 16.05 ± 0.07 c | |
60 | 22,845 ± 17 j | 1711.69 ± 28.96 j | 7.49 ± 0.13 i | |
90 | 22,853 ± 0 j | 2294.33 ± 5.46 h | 10.04 ± 0.02 e | |
120 | 30,281 ± 0 f | 2484.93 ± 41.54 g | 8.21 ± 0.14 h | |
150 | 62,989 ± 5 c | 3427.59 ± 31.37 c | 5.44 ± 0.05 l | |
LSD 0.05 | 8.553 | 38.24 | 0.2055 | |
CV% | 0.0 | 1.1 | 1.3 | |
Beta-carotene (µg/g) | ||||
‘Acadia’ | 0 | 5520 ± 1 n | 478.82 ± 3.07 n | 8.67 ± 0.06 l |
30 | 7222 ± 2 m | 1098.44 ± 15.38 l | 15.21 ± 0.21 k | |
60 | 11,384 ± 4 h | 3981.27 ± 45.26 b | 34.97 ± 0.40 b | |
90 | 14,237 ± 2 g | 2509.91 ± 48.92 g | 17.63 ± 0.34 i | |
120 | 18,377 ± 2 d | 3231.47 ± 14.21 e | 17.58 ± 0.08 i | |
150 | 18,466 ± 3 c | 3912.12 ± 6.89 c | 21.19 ± 0.04 g | |
‘Crosstrek’ | 0 | 4765 ± 5 q | 44.23 ± 0.71 p | 0.93 ± 0.01 o |
30 | 4836 ± 3 p | 158.86 ± 1.66 o | 3.28 ± 0.03 n | |
60 | 8634 ± 1.8 l | 604.32 ± 6.98 m | 6.70 ± 0.08 m | |
90 | 8687 ± 2 k | 1897.66 ± 4.02 i | 21.84 ± 0.05 f | |
120 | 18,932 ± 1 b | 1650.80 ± 34.98 j | 8.72 ± 0.18 l | |
150 | 19,036 ± 8 a | 2975.48 6.64 f | 15.63 ± 0.03 j | |
‘Traverse’ | 0 | 4655 ± 2 r | 40.06 ± 2.17 p | 0.86 ± 0.05 o |
30 | 5136 ± 4 o | 1214.81 ± 9.08 k | 23.65 ± 0.18 d | |
60 | 9523 ± 2 j | 2134.69 ± 26.85 h | 22.42 ± 0.28 e | |
90 | 11,242 ± 3 i | 3970.24 ± 4.64 b | 35.32 ± 0.04 a | |
120 | 17,043 ± 3 f | 4212.31 ± 7.97 a | 24.72 ± 0.05 c | |
150 | 17,114 ± 1 e | 3309.84 ± 49.73 d | 19.34 ± 0.29 h | |
LSD 0.05 | 5.356 | 38.32 | 0.2969 | |
CV% | 0.0 | 1.1 | 1.1 | |
Zeaxanthin (µg/g) | ||||
‘Acadia’ | 0 | 5441 ± 0 r | 82.76 ± 0.42 k | 1.52 ± 0.01 c |
30 | 9966 ± 1 m | 135.06 ± 3.91 h | 1.35 ± 0.04 d | |
60 | 15,336 ± 1 k | 379.61 ± 6.32 b | 2.47 ± 0.04 b | |
90 | 27,988 ± 2 g | 156.47 ± 4.97 g | 0.56 ± 0.02 h | |
120 | 35,685 ± 4 f | 442.97 ± 0.51 a | 1.24 ± 0.00 e | |
150 | 47,654 ± 5 a | 94.7 ± 0.21 j | 0.15 ± 0.08 l | |
‘Crosstrek’ | 0 | 7847 ± 1 p | 23.13 ± 0.23 m | 0.29 ± 0.00 k |
30 | 9638 ± 1 n | 46.50 ± 0.27 l | 0.48 ± 0.00 i | |
60 | 13,956 ± 4 l | 48.02 ± 0.24 l | 0.34 ± 0.00 jk | |
90 | 25,474 ± 3 h | 219.92 ± 1.82 e | 0.86 ± 0.01 g | |
120 | 4415 ± 3 e | 129.7 ± 5.02 h | 2.62 ± 0.55 a | |
150 | 44,214 ± 3 d | 253.38 ± 0.76 c | 0.57 ± 0.00 h | |
‘Traverse’ | 0 | 5939 ± 1 q | 20.98 ± 0.18 m | 0.35 ± 0.00 j |
30 | 8061 ± 1 o | 102.52 ± 0.24 i | 1.27 ± 0.00 e | |
60 | 18,984 ± 1 j | 257.31 ± 1.30 c | 1.35 ± 0.01 d | |
90 | 24,775 ± 3 i | 229.74 ± 10.05 d | 0.93 ± 0.04 f | |
120 | 46,044 ± 11 c | 173.15 ± 1.58 f | 0.38 ± 0.00 j | |
150 | 46,554 ± 3 b | 47.71 ± 1.41 l | 0.10 ± 0.00 l | |
LSD 0.05 | 4.288 | 5.753 | 0.05292 | |
CV% | 0.0 | 2.2 | 3.3 |
Cultivar | Nitrogen Level (mg/L) | Undigested | Intestinal |
---|---|---|---|
FRAP (mM/g) | |||
‘Acadia’ | 0 | 28.71 ± 1.53 g | 2.87 ± 0.13 e |
30 | 34.98 ± 2.50 d | 4.51 ± 0.82 cde | |
60 | 38.93 ± 1.74 b | 7.49 ± 2.45 abc | |
90 | 38.76 ± 1.00 b | 4.51 ± 0.75 cde | |
120 | 39.37 ± 1.04 b | 6.87 ± 1.13 abcd | |
150 | 35.48 ± 0.50 cd | 8.43 ± 1.30 ab | |
‘Crosstrek’ | 0 | 23.76 ± 0.76 i | 3.58 ± 0.10 de |
30 | 25.71 ± 0.50 h | 4.00 ± 0.35 cde | |
60 | 29.76 ± 0.76 fg | 4.65 ± 0.52 cde | |
90 | 30.09 ± 0.76 f | 5.26 ± 0.58 bcde | |
120 | 36.48 ± 0.76 c | 5.84 ± 0.27 abcde | |
150 | 36.37 ± 0.29 c | 9.00 ± 0.59 a | |
‘Traverse’ | 0 | 24.93 ± 1.04 hi | 3.11 ± 0.50 e |
30 | 35.65 ± 0.76 cd | 5.50 ± 2.81 abcde | |
60 | 32.59 ± 0.75 e | 4.65 ± 1.17 cde | |
90 | 35.48 ± 1.32 cd | 5.86 ± 1.96 abcde | |
120 | 37.68 ± 0.76 a | 6.08 ± 0.65 abcde | |
150 | 35.65 ± 1.04 cd | 6.34 ± 0.50 abcde | |
LSD 0.05 | 1.255 | ||
CV% | 2.3 | ||
DPPH (IC50, mg/mL) | |||
‘Acadia’ | 0 | 1.90 ± 0.03 cdef | 2.27 ± 0.51 a |
30 | 1.96 ± 1.96 efg | 2.54 ± 0.85 a | |
60 | 2.04 ± 0.02 gh | 1.83 ± 0.40 a | |
90 | 1.89 ± 0.03 cde | 2.49 ± 0.30 a | |
120 | 2.08 ± 0.06 hi | 3.68 ± 0.08 ab | |
150 | 2.69 ± 0.05 k | 4.79 ± 0.21 ab | |
‘Crosstrek’ | 0 | 1.85 ± 0.04 cd | 4.91 ± 2.53 ab |
30 | 1.93 ± 0.02 def | 3.99 ± 1.62 ab | |
60 | 1.95 ± 0.02 efg | 2.81 ± 0.49 a | |
90 | 1.83 ± 0.01 c | 5.42 ± 0.43 ab | |
120 | 2.16 ± 0.03 i | 5.36 ± 0.82 ab | |
150 | 2.29 ± 0.02 j | 7.82 ± 3.94 b | |
‘Traverse’ | 0 | 1.52 ± 0.02 a | 3.22 ± 0.64 ab |
30 | 1.67 ± 0.01 b | 3.95 ± 0.70 ab | |
60 | 1.84 ± 0.01 cd | 4.24 ± 0.82 ab | |
90 | 1.58 ± 0.07 ab | 2.59 ± 0.53 a | |
120 | 1.89 ± 0.02 cde | 3.25 ± 0.55 ab | |
150 | 1.99 ± 0.00 fgh | 3.39 ± 0.28 ab | |
ABTS (IC50, mg/mL) | |||
‘Acadia’ | 0 | 2.00 ± 0.03 b | 2.28 ± 0.04 abc |
30 | 3.37 ± 0.02 g | 2.23 ± 0.19 ab | |
60 | 3.73 ± 0.07 hi | 2.59 ± 0.15 abcd | |
90 | 2.59 ± 0.01 de | 3.00 ± 0.61 cd | |
120 | 2.30 ± 0.02 c | 2.84 ± 0.20 bcd | |
150 | 2.18 ± 0.05 c | 3.13 ± 0.23 d | |
‘Crosstrek’ | 0 | 1.82 ± 0.03 a | 2.11 ± 0.03 ab |
30 | 2.88 ± 0.08 f | 2.10 ± 0.03 ab | |
60 | 3.61 ± 0.03 h | 1.96 ± 0.08 a | |
90 | 2.51 ± 0.08 de | 1.99 ± 0.15 a | |
120 | 2.51 ± 0.06 de | 2.21 ± 0.25 ab | |
150 | 1.93 ± 0.06 ab | 2.29 ± 0.05 abc | |
‘Traverse’ | 0 | 1.93 ± 0.03 ab | 2.52 ± 0.05 abcd |
30 | 2.95 ± 0.06 f | 2.16 ± 0.05 ab | |
60 | 3.76 ± 0.05 i | 1.91 ± 0.25 a | |
90 | 2.64 ± 0.03 e | 2.09 ± 0.19 ab | |
120 | 2.46 ± 0.06 d | 2.23 ± 0.60 ab | |
150 | 2.18 ± 0.01 c | 2.57 ± 0.03 abcd |
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Bhengu, N.M.; Mianda, S.M.; Maboko, M.M.; Sivakumar, D. The Effects of Nitrogen Application and Varietal Variation on the Product Quality and In Vitro Bioaccessibility of Bioactive Compounds of Baby Spinach Varieties Grown in a Soilless Growth Medium. Foods 2024, 13, 2667. https://doi.org/10.3390/foods13172667
Bhengu NM, Mianda SM, Maboko MM, Sivakumar D. The Effects of Nitrogen Application and Varietal Variation on the Product Quality and In Vitro Bioaccessibility of Bioactive Compounds of Baby Spinach Varieties Grown in a Soilless Growth Medium. Foods. 2024; 13(17):2667. https://doi.org/10.3390/foods13172667
Chicago/Turabian StyleBhengu, Nhlanzeko Mbalenhle, Sephora Mutombo Mianda, Martin Makgose Maboko, and Dharini Sivakumar. 2024. "The Effects of Nitrogen Application and Varietal Variation on the Product Quality and In Vitro Bioaccessibility of Bioactive Compounds of Baby Spinach Varieties Grown in a Soilless Growth Medium" Foods 13, no. 17: 2667. https://doi.org/10.3390/foods13172667