Table 3.
Antioxidant compounds in soursop seeds extract obtained by single-mode (SM) and combined-mode (CM) subcritical water extraction (SWE) and Soxhlet (SOX) technique using ethanol (EtOH) as a solvent.
| Phenolic Compound | SWE SM 70 °C (mg∙g−1) | SWE SM 130 °C (mg∙g−1) | SWE CM 70 °C (mg∙g−1) | SWE CM 130 °C (mg∙g−1) | SOX EtOH (mg∙g−1) | |
|---|---|---|---|---|---|---|
| Phenolic acid | ||||||
| 1 | 3,4 Dihydroxybenzoic acid | 0.0021 ± 0.0 | 0.0374 ± 0.0025 | 0.0033 ± 0.0003 | 0.0474 ± 0.0051 | 0.0032 ± 0.0007 |
| 2 | 4- Aminobenzoic acid* | < LOQ | 0.0194 ± 0.0026 | < LOQ | 0.0220 ± 0.0058 | <LOQ |
| 3 | 4-Hydroxymethylbenzoic acid* | < LOQ | 0.0135 ± 0.015 | < LOQ | 0.0267 ± 0.0028 | 0.0005 ± 0.0003 |
| 4 | Caffeic acid | 0.0015 ± 0.0001 | 0.0152 ± 0.0010 | 0.0017 ± 0.0003 | 0.0109 ± 0.0015 | 0.0011 ± 0.0 |
| 5 | Cinnamic acid | < LOQ | < LOQ | < LOQ | < LOQ | < LOQ |
| 6 | Chlorogenic acid | < LOQ | < LOQ | < LOQ | < LOQ | < LOQ |
| 7 | Ellagic acid* | 0.0043 ± 0.0005 | 0.0382 ± 0.0024 | 0.0018 ± 0.0 | 0.0080 ± 0.0014 | 0.0044 ± 0.0010 |
| 8 | Ferulic acid* | 0.0052 ± 0.0018 | 0.0073 ± 0.0011 | 0.0038 ± 0.0005 | 0.0074 ± 0.0010 | 0.0031 ± 0.0003 |
| 9 | Gallic acid | < LOQ | 0.0014 ± 0.0002 | < LOQ | 0.0016 ± 0.0001 | <LOQ |
| 10 | Mandelic acid* | 0.0012 ± 0.0002 | 0.0039 ± 0.0005 | 0.0014 ± 0.0 | 0.0056 ± 0.0001 | 0.0013 ± 0.0002 |
| 11 | p-Anisic acid* | <LOQ | < LOQ | <LOQ | <LOQ | <LOQ |
| 12 | p-Coumaric acid | 0.0182 ± 0.0036 | 0.0189 ± 0.0028 | 0.0166 ± 0.0017 | 0.0243 ± 0.0046 | 0.0270 ± 0.0058 |
| 13 | Rosmarinic acid* | <LOQ | <LOQ | <LOQ | 0.0001 ± 0.0 | <LOQ |
| 14 | Salicylic acid* | 0.0024 ± 0.0 | 0.0028 ± 0.0002 | 0.0001 ± 0.0 | 0.0033 ± 0.0004 | <LOQ |
| 15 | Sinapic acid* | nd | 0.0004 ± 0.0001 | 0.0006 ± 0.0002 | 0.0014 ± 0.0 | <LOQ |
| 16 | Syringic acid | <LOQ | 0.0017 ± 0.0 | < LOQ | <LOQ | <LOQ |
| 17 | Vanillic acid* | 0.0060 ± 0.0010a | 0.0400 ± 0.0047 | 0.0086 ± 0.0006 | 0.0635 ± 0.0068 | 0.0141 ± 0.0019 |
| Flavonoid | ||||||
| 18 | Apeginin* | <LOQ | nd | <LOQ | <LOQ | <LOQ |
| 19 | Catechin | <LOQ | nd | nd | nd | <LOQ |
| 20 | Chrysin* | <LOQ | <LOQ | nd | <LOQ | <LOQ |
| 21 | Epicatechin* | <LOQ | 0.0005 ± 0.0 | 0.0001 ± 0.0 | <LOQ | <LOQ |
| 22 | Eriodictyol* | < LOQ | < LOQ | < LOQ | < LOQ | < LOQ |
| 23 | Fustin* | <LOQ | <LOQ | <LOQ | <LOQ | <LOQ |
| 24 | Galagngina* | <LOQ | <LOQ | <LOQ | <LOQ | <LOQ |
| 25 | Hispidulin* | <LOQ | <LOQ | <LOQ | <LOQ | <LOQ |
| 26 | Kaempferol* | 0.0411 ± 0.0065 | <LOQ | 0.0025 ± 0.0007 | <LOQ | <LOQ |
| 27 | Myricetin* | 0.0008 ± 0.0 | 0.0011 ± 0.0 | 0.0009 ± 0.0 | 0.0026 ± 0.0001 | 0.0012 ± 0.0 |
| 28 | Naringenin* | <LOQ | <LOQ | <LOQ | <LOQ | <LOQ |
| 29 | Pinocembrin* | <LOQ | <LOQ | < LOQ | nd | nd |
| 30 | Quercetin | 0.0117 ± 0.0011 | 0.0006 ± 0.0001 | 0.0051 ± 0.0007 | 0.0028 ± 0.0002 | 0.0039 ± 0.0006 |
| 31 | Rutin | <LOQ | <LOQ | < LOQ | <LOQ | <LOQ |
| 32 | Taxifolin* | <LOQ | 0.0004 ± 0.0001 | < LOQ | <LOQ | <LOQ |
| 33 | Vitexina* | < LOQ | < LOQ | < LOQ | < LOQ | < LOQ |
| Stilbene | ||||||
| 34 | Resveratrol | nd | nd | nd | <LOQ | nd |
| Phenolic Aldehyde | ||||||
| 35 | Coniferaldehyde* | <LOQ | 0.0005 ± 0.0001 | < LOQ | 0.0014 ± 0.0002 | <LOQ |
| 36 | Sinapaldehyde* | <LOQ | <LOQ | <LOQ | <LOQ | <LOQ |
| 37 | Syringaldehyde* | <LOQ | 0.0022 ± 0.0008 | <LOQ | <LOQ | <LOQ |
| 38 | Vanillin | 0.0003 ± 0.0001 | 0.0152 ± 0.0025 | < LOQ | 0.0357 ± 0.0071 | 0.0008 ± 0.0004 |
| Coumarin | ||||||
| 39 | Scopoletin* | <LOQ | nd | < LOQ | nd | <LOQ |
| 40 | Umbelliferone* | <LOQ | 0.0008 ± 0.0001 | < LOQ | 0.0009 ± 0.0003 | <LOQ |
| Phenolic Diterpene | ||||||
| 41 | Carnosol* | <LOQ | <LOQ | < LOQ | <LOQ | <LOQ |
| Total Phenolic Content (mg g−1) | 0.0948 | 0.2214 | 0.0465 | 0.2656 | 0.0606 | |
< LOQ, not quantifiable.
nd: not detected; * reported for the first time.