Table 3 Available analytical standards and assay methods for selected medicinal plant compounds
Plant material | Identified Analytical markers | Commercial sources | Smallest commercial unit available, purity and/cost (Euros-€) | Cost per mg/mL of marker (Euros-€)) | Analytical methods for the plant material mentioned in local or WHO Pharmacopoeia | Assay methods already developed for the compounds in same or other materials |
|---|---|---|---|---|---|---|
Eucalyptus globulus oil | Aromadendrine (dihydrokaempferol) | Sigma‒Aldrich/Supelco | Analytical standard-530/5 mg ≥95% HPLC grade-221/10 mg ≥ 95% LC/MS-ELSD-421/1 mg | 106.0 22.1 421 | WHO monographs &African pharmacopoeia-identification tests for 1,8-cineole in oil & leaf materials. TLC fingerprint for leaf materials with 1,8-cineole as reference [10, 13]. | Gas chromatography FID & MS method for quantification of oil components [25, 101] |
α-terpineol | Sigma‒Aldrich/Supelco | Analytical standard (≥ 95%)-63.9/100 mg | 0.6 | |||
globulol | Sigma‒Aldrich | ≥ 98.5% (sum of enantiomers, GC)- 247/100 mg | 2.5 | |||
1,8-cineol (eucalyptol) | Sigma‒Aldrich/Supelco | Analytical standard- 48.3/1 mL | 48.3 | |||
Aloes -whole leaf products | Aloin A | Sigma‒Aldrich | Analytical standard- 440/10 mg | 44.0 | WHO monographs-Thin-layer chromatography, microchemical analyses to identify anthracenes, Spectrophotometry-to determine total glycosides as aloin [10] | HPLC-DAD/MS quantification methods for anthracenes in aloe vera samples [102] |
Aloin B | Sigma‒Aldrich | Phyproof® Reference Substance- 605/10 mg | 60.5 | |||
Aloe emodin | Sigma‒Aldrich | Analytical standard 311/10 mg | 31.1 | |||
Aloe vera gel | Acemannan | Toronto Research chemicals | Technical grade- 208.3/10 mg | 20.8 | Chemical test for carbohydrates; Polysaccharide composition analysis by gas–liquid chromatography [10] | Molecular Exclusion Chromatography [103] UV‒Vis Spectrophotometry [104] |
D-Mannose 6 phosphate | Sigma‒Aldrich | ≥ 98% (HPLC) (sodium salt)- 354.0/100 mg | 3.5 | None found | ||
Albizia coriaria stem bark | Lupeol | Sigma‒Aldrich | Analytical standard-130/10 mg | 13.0 | No monographs for Albizia coriaria stem bark materials | |
lupenone | Toronto Research chemicals | Analytical standard-170/2.5 mg | 68.0 | HPLC-DAD quantification method for triterpenoids in Albizia inundata [107] | ||
Betulinic acid | Sigma‒Aldrich/Supelco | Analytical standard 95.1/10 mg ≥ 98% (HPLC)- 70/5 mg | 9.5 14.0 | HPLC-DAD quantification method for betulinic acid in Albizia lebbeck [108] | ||
Catechin | Sigma‒Aldrich/Supelco | Analytical standard − 307/10 mg | 30.7 | HPLC-DAD quantification method Albizia lebbeck [109], | ||
Mangifera indica leaf or stem bark | Mangiferin | Sigma‒Aldrich/Supelco | Analytical standard-108/10 mg | 10.8 | No monographs for Mangifera indica leaf or stem bark materials | HPLC-UV quantification method for mangiferin [110] |
Catechin | Sigma‒Aldrich/Supelco | Analytical standard − 307/10 mg | 30.7 | HPLC-UV quantification method for phenolic compounds [111] | ||
Epicatechin | Not found | N/A | ||||
Gallic acid | Sigma‒Aldrich | Phyproof® Reference Substance − 345/100 mg | 34.5 | |||
Quercetin | Sigma‒Aldrich | United States Pharmacopeia (USP) Reference Standard- 357/200 mg phyproof® Reference Substance- 253/20 mg ≥ 95% (HPLC)- 68.3/10 g | 1.8 12.7 6.8 | |||
Azadirachta indica stem bark or leaf | Azadirachtin | Sigma‒Aldrich | Phyproof® Reference Substance- 403/5 mg ~ 95%-249/0.5 mg | 80.6 498.0 | WHO monographs-high-performance liquid chromatography quantification of tetranortriterpenes in oil and leaf materials [11] | HPLC-UV quantification method for Azadirachtins [114] |
Nimbin | Toronto Research chemicals | Analytical standard-105/1 mg | 105.0 | HPLC-UV quantification method for nimbin [115] | ||
Nimbidin | Not found | N/A | None found | |||
Nimbolide | Sigma‒Aldrich | ≥ 98%-624/5 mg | 124.8 | HPLC-UV quantification method for nimbolide [116] | ||
Mahmoodin | Not found | N/A | None found | |||
Zingiber officinalis rhizome | 8-gingerol | Sigma‒Aldrich/Supelco | Analytical standard 489.0/10 mg | 48.9 | WHO monographs-Thin-layer chromatography fingerprinting to identify gingerols and shogaols; quantitative gas chromatography and high-performance liquid chromatography analyses of ginger oils for gingerols, Shogaols [10] | HPLC‒MS quantification methods for gingerols and related compounds [117] |
10-gingerol | Sigma‒Aldrich | Analytical standard-546/10 mg ≥ 98% (HPLC)-276/5 mg phyproof® Reference Substance-472/10 mg | 54.6 55.2 47.2 | |||
12-gingerol | Not found | N/A | ||||
6-gingerol | Sigma‒Aldrich | Analytical standard- 448/10 mg ≥ 98% (HPLC)- 358/5 mg phyproof® Reference Substance- 472/10 mg | 44.8 71.6 47.2 | |||
6-shogaol | Sigma‒Aldrich | Analytical standard-538/10 mg Phyproof® Reference Substance- 657/10 mg | 53.8 65.7 | |||
Zingerone | Sigma‒Aldrich | Analytical standard- 84.50/50 mg | 1.7 | None found | ||
Warburghia ugandensis stem bark | Polygodial | Sigma‒Aldrich | ≥97% (HPLC)-216/10 mg | 21.6 | No monograph for Warburghia ugandensis stem bark | None found |
Bemadienolide | Not available | N/A | None found | |||
Muzigadial | Not available | N/A | None found | |||
Warbuganal | Not available | N/A | None found | |||
Warbugadione | Not available | N/A | None found | |||
Warbugadial | Not available | N/A | None found | |||
Warbugin | Not available | N/A | None found | |||
Ugandensolide | Not available | N/A | None found | |||
Ugandensidial | Not available | N/A | None found |