melatonin -- keywords and MeSH

("Melatonin"[mesh] OR melatonin OR “N-Acetyl-5-methoxytryptamine” OR Melatoniin* OR Melatonin* OR “armonil noche” OR melatol OR nochix OR repentil OR circadin OR HT903 OR “HT 903” OR HT-903 OR melapure OR meloset OR armonia OR melamil OR benedorm[tiab] OR cronocaps OR normolem OR remedin OR revenox OR sleepwell OR transzone OR “BP 2013”[tiab] OR BP2013 OR JL5DK93RCL)

I have included alternate names for melatonin obtained from Martindale's and from the MeSH entry term list.  I removed the following terms that are common terms for other concepts or are not found by PubMed and cause retrieval of irrelevant results: Novel OR “buenes noches” OR “BP-2013”[tiab] OR “bio-melatonin”[tiab]

luteine -- keyword

(Luteine OR Kesselringine OR lutein OR trans-Lutein OR all-trans-Xanthophyll OR all-trans-Lutein OR Xanthophyll OR luteol OR "oro glo 7" OR "OS 24" OR floraglo OR "e 161" OR "e 161b" OR bo-xan OR "Lutein"[Mesh])

Vitamin E

(Vitamin E OR tocopherol* OR alpha-tocopherol* OR beta-tocopherol* OR gamma-tocopherol* OR tocotrienol* )

echinacea -- combination keyword, MeSH

("Echinacea"[Mesh] OR echinacea OR rubdeckia OR coneflower OR ubiquinone OR echinacoside OR inulin OR sesquiterpenes)