Table 4 Non-experimental validation of plants used for stomach problems, pain and internal parasites in Trinidad and Tobago

Aframomum melegueta

A decoction of the leaves of Aframomum melegueta is used for rheumatism and as an anti-emetic agent and a decoction of the fruits for dysenteric conditions. The methanol extracts of the seeds were significantly active against Gram (+) and Gram (-) bacteria (S.aureus, B.subtilis, E.coli, P.aeruginosa) and fungi (C. albicans, A.niger). Aframomum melegueta has antimicrobial properties against E. coli and Bacillus cereus. The antioxidant extracts of Aframomum melegueta was attributed to its phenolic components. Scabies and acute poststreptococcal glomerulonephritis (the latter can be caused by several bacterial and viral infections) are frequently associated with S. aureus in Trinidad.

34–36

Ambrosia cumanenesis

The ambrosanolide-type sesquiterpene lactone cumanin (from Ambrosia psilostachya) showed a potent inhibitory effect in NO production (IC₅₀ = 9.38 ± 0.38 μM) with low cytotoxicity.

37

Aristolochia species

The Chinese herb "Mu Tong" has included Aristolochia manshuriensis only since the 1950s. The classical Chinese herbal literature until the mid 17th century identifies "Mu Tong" as several Akebia species. From the 17th until the early 20th century "Mu Tong" was based on Clematis species. Renal failure due to ingestion of large doses of Aristolochia manshuriensis has been reported in China and other countries while no toxicity was recorded in traditional Chinese herbal texts. Aristolochia's topical anti-inflammatory activity has been recently described. Aristolochic acids, isolated from Aristolochia longa inhibited Escherichia coli, Pseudomonas aeruginosa, Streptococcus faecalis, Staphylococcus aureus and Staphylococcus epidermidis. The chloroform and hexane extracts of Aristolochia trilobata leaves and bark were active against Escherichia coli and Pseudomonas aeruginosa and Staphylococcus aureus.

38, 39

Bambusa vulgaris

The antiinflammatory effect of the methanol extract of the leaves of Bambusa arundinacea was significant when compared to standard drugs validating its use in Ayurvedic medicine. The methanol extract of Bambusa arundinacea also showed antihypersensitivity activity, immunosuppressive activity, wound healing property and antibacterial activity experimentally.

40

Bidens pilosa

The "Shidachuan" which was originally recorded in "Ben Cao Gang Mu Shi Yi" (A Supplement to the Compendium of Materia Medica) is "Longyacao" (Agrimonia pilosa). "Shijianchuan" should be "Guizhencao" (Bidens bipinata). Bioactive polyacetylenes were found in the methanolic extract of Bidens pilosa (whole plant). The antiinflammatory effect of aqueous extracts of the three plants Bidens pilosa var. minor (Blume) Sherff, Bidens pilosa and Bidens chilensis DC was significant. The immuno-suppressive activity of Bidens pilosa is attributed to the polyacetylene isolated from leaves. The water extract of Bidens pilosa showed a higher activity against Bacillus cereus and Escherichia coli than gentamycin sulphate. In one study diarrheic children in Trinidad were found to be positive for enteropathogenic E. coli.

41–43

Bixa orellana

Bixa orellana exhibited antimicrobial activity with a low MIC against Escherichia coli (0.8 microg/ml) compared to gentamycin sulfate (0.9 8 g/ml). Bixa orellana exhibited a better MIC against Bacillus cereus (0.2 microg/ml) than gentamycin sulfate (0.5 microg/ml).

43

Cajanus cajan

Extracts of roots and leaves of Cajanus cajan yielded 8 compounds: betulinic acid, biochanin A, cajanol, genistein and 2'-hydroxygenistein, longistylin A and C, and pinostrobin. The stilbenes, longistylin A and C, and betulinic acid showed moderate in vitro activity against chloroquine-sensitive Plasmodium falciparum. A protein was purified from the leaves and may enhance body immunosurveillance. Cajanus indicus protein possesses both a preventive and curative role against chloroform-induced hepatotoxicity and may act by an anti-oxidative defence mechanism.

44–46

Capraria biflora

The dried leaves of Capraria biflora (aqueous extract (50–200 mg kg(-1)) produced a moderate analgesic effect.

47

Cecropia peltata

Cecropia pachystachya has antioxidant properties. The two flavonoids orientin and iso-orientin, isolated from the active butanolic fraction could be responsible for the observed anxiolytic-like effect of C. glazioui. Steroids and amino acids in C. peltata may account for the antimicrobial activity exhibited against E. coli.

48, 49

Centropogon cornutus

Centropogon cornutus has a synonym Lobelia cornuta. Three new piperidine alkaloids were isolated from stems, leaves and flowers of Lobelia laxiflora. The residues obtained from the ethanol extracts from stems, leaves, and flowers showed anti-inflammatory protential.

50

Chamaesyce hirta syn. Euphorbia hirta

Euphorbia hirta aqueous extract is used for dysentery, colic, bronchial infections and to treat ulcers. The plant contains eucocyanidol, quercitol, camphol, quercetrin, dihydroellagitannins and dimeric hydrolysable tannins – euphorbins. Ethanolic extracts of the aerial parts of the plant showed antimicrobial activity against Escherichia coli (enteropathogen), Proteus vulgaris, Pseudomonas aeruginosa and Staphylococcus aureus.

51–53

Citharexylum spinosum

Six new iridoid glucosides and one known iridoid glucoside were isolated from the fruits and other parts of Citharexylum caudatum. The aerial parts of Citharexylum spinosum L., contain five iridoid glucosides, and one known lignan glucoside. When formulated in jojoba oil and applied to mice tails followed by infection with Schistosoma mansoni cercariae, the iridoid mixture from leaves of Citharexylum quadrangular blocked cercarial penetration and caused significant reduction (94%; P < 0.05) in worm burden in treated mice in comparison to controls.

54–56

Cocos nucifera

Coconut kernel fiber can protect cells from loss of oxidative capacity with the administration of the procarcinogen 1,2-dimethylhydrazine (DMH). The alcoholic extract of ripe dried coconut shell of Cocus nucifera showed antifungal activity against all dermatophytes tested with twice the concentration needed against E. flocossum (200 ug/ml).Cocos nucifera fruit exocarp has significant activity against all enteropathogens tested. All the strains tested were resistant to chloramphenicol; the two Escherichia coli species, the two Shigella flexneri species and the two Salmonella sp. species were sensitive to trimethoprim, and the two Shigella sonnei species were resistant. The authors concluded that coconut could be used as an alternative method to treat drug resistant enteric infections.

57, 58

Cola nitida

In Nigeria, Cola accuminata, Cola nitida and Cola milleni are used in ethnobotany for the treatment of diarrhea and dysentery.Cola species contain caffeine, koletein and kolatin alkaloids, proanthocyanin, magnesium, sodium, potassium bromide, cobalt, caesium, zinc and selenium. The Mycobacterium bovis was susceptible at 1000 μg/ml of methanol extract root bark of both Cola nitida and Cola milleni but insensitive to methanol extracts of both the leaves and stem-bark of the three Cola sp. tested. The MIC of the methanol root extract of Cola nitida against Mycobacterium bovis is 125 μg/ml. The MIC of methanol root extract of Cola nitida against the six ATCC strain of Mycobacterium vaccae ranged from 500 μg/ml to above 1000 μg/ml. The control Rifampicin is active against M. bovis at 5 μg and 10 μg/ml.

59

Cucurbita species

The minimum inhibitory concentration (MIC) of 23 gr. of pumpkin seed (+/- 73 seeds) (Cucurbita maxima) in 100 ml. distilled water as an antiparasitic agent using canine tapeworms with an intestinal isolation of 5 to 6 hours was determined. Alterations in helminthic motility were found at a dose of > 23 gr. There is a protheolithic effect with an average survival time of 38.4 minutes. The anthelmintic effect is increased at 30 and 32 gr.

60

Dorstenia contrajerva

Dorstenia species contain furanocoumarins with analgesic, anti-inflammatory, antibacterial, antiviral, anticoagulant, and photosensitizing activities. Prenylated chalcones are also found and may have anti-carcinogenic and antiproliferative properties. Dorstenia contrajerva was active toward Giardia lamblia with IC(50)<38 mug/ml. This antiprotozoal activity supports the popular use to treat diarrhoea and dysentery.

61–63

Eleusine indica

Eleusine indica ethanol extract showed activity against vesicular stomatitis virus. The plant contains hydrocyanic acid.

64

Eupatorium macro-phyllum

The ethanol extract of the leaves of Eupatorium adenophorum (100, 200 and 300 mg/kg, po) showed significant analgesic activity, compared to standard drugs diclofenac sodium and pentazocine Petroleum ether and methanolic extracts of leaves of Eupatorium ayapana showed broad spectrum antibacterial activity at the tested concentration (250–1000 μg/ml) except against Shigella dysenteriae. The petroleum ether extract also showed antifungal activity. Two extracts (dichloromethane and methanol), of the dried stems and leaves of Eupatorium inulaefolium, the S2 fraction of the hexane extract and neurolenin B from the dichloro-methane extract, showed statistically significant antiplasmodial activity

65–67

Ferula a safoetida

A Ferula asafoetida gum extract (3 mg/ml), decreased the average amplitude of spontaneous contractions of the isolated guinea-pig ileum to 54 +/- 7% of control. Ferula asafoetida gum extract (0.3–2.2 mg/100 g body weight) reduced the mean arterial blood pressure in anaesthetised rats.

68

Jatropha curcas

Two deoxypreussomerins were isolated from stems of Jatropha curcas. Two compounds had antibacterial constituents. Jatropha curcas crude bark extract accelerates the healing process of wounds on Wistar albino rats by increasing the skin breaking strength, granulation tissue breaking strength, wound contraction, dry granulation tissue weight and hydroxyproline levels. A significant decrease in epithelization period was also observed

69, 70

Momordia charantia

Momordica charantia may induce both intestinal and also systemic anti-inflammatory responses and may have antiviral activity.

71, 72

Morinda citrifolia

The lyophilised aqueous extract of roots of Morinda citrifolia produced a dose-related, central analgesic activity in mice. The analgesic efficacy of the Noni extract was less strong than morphine but non-addictive and had no side effects. Morinda citrifolia fruit powder demonstrated over 70% COX-1 inhibition. The extracts from Morinda citrifolia leaf (45%) showed moderate inhibition on COX-1. The extracts from Morinda citrifolia bark (27%) and Morinda citrifolia fresh fruit juice (38%) presented low inhibition on COX-1. The extract from Morinda officinalis root was inactive (9.87%) at a concentration of 3.4 mg/ml.

73–75

Neurolaena lobata

Neurolaena lobata has antinociceptive and antibacterial effects. When tested against Brugia pahangi, a lymphatic dwelling filarial worm, the ethanol extract of Neurolaena lobata showed potential macro- and micro-filaricidal activity.

76

Nicotiana tabacum

The lack of nicotine-induced analgesia assessed by the tail flick reflex test in female rats is consistent with human studies showing that nicotine reduces pain elicited by brief noxious cutaneous stimulation in male but not female subjects.

77

Peperomia rotundifolia

In south-east Asia, Peperomia pellucida is used for wounds, skin problems, abdominal pain and other pains and for headache. Peperomia pellucida is reported to have analgesic activity in mice, antibacterial activity against Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus, and antifungal activity. Peperomia pellucida ethyl-acetate soluble extracts and crude methanolic extracts were active against Gram-positive and Gram-negative bacteria.

78

Petiveria alliacea

Petiveria alliacea extract showed an antinociceptive effect which account for its popular use as an analgesic. The oral administration of Petiveria alliacea root crude lyophilized extract at the highest dose of extract tested (43.9 mg/kg body wt.) significantly reduced the number of migrating neutrophils, mononuclear cells and eosinophils. The Petiveria alliacea root extract also showed a significant analgesic effect. Thiosulfinates, trisulfides and benzylsulfinic acid are antimicrobial compounds, with the benzyl-containing thiosulfinates having the broadest spectrum of antimicrobial activity.

79–81

Portulaca oleracea

The ingestion of purslane (Portulaca oleracea) leaves may have a protective effect against oxidative stress caused by vitamin A deficiency.

82

Punica granatum

Punica granatum was used by Egyptians in ancient times as a treatment for tapeworm and other parasites. A pomegranate extract at a low extract concentration (0.01% v/v) delayed bacterial growth of Staphylococcus aureus FRI 722, while a higher concentration (1% v/v) eliminated bacterial growth.

83

Rosmarinus officinalis

Rosmarinus officinalis has historically been used as ananalgesic and antirheumatic herb. The aqueous and ethanol extracts of Rosmarinus officinalis L. aerial parts induced a significant antinociceptive activity. In an observational study, a combination of reduced iso-alpha-acids from hops, rosemary extract and oleanolic acid decreased pain in patients suffering from rheumatic conditions and osteoarthritis.

84, 85

Solanum melongena

Solanum melongena contains significant quantities of histamine and serotonin.

86

Scoparia dulcis

Scoparia dulcis has traditionally been used to treat stomach troubles, inflammation, hemorrhoids, and hepatosis and as an analgesic. Biologically active substances from Scoparia dulcis include scoparic acid A, scoparic acid B, scopadulcic acid A and B, scopadulciol and scopadulin. The chloroform/methanol fractions Scoparia dulcis showed antimicrobial activity against the human pathogenic bacteria Salmonella typhii, Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Proteus vulgaris and the plant pathogenic fungi Alternaria macrospora, Candida albicans, Aspergillus niger, and Fusarium oxysporum.

87

Tagetes patula

Tagetes erecta callus cultures produce ascorbic acid as well as insecticidal pyrethrins.Tagetes patula oil contains several compounds with the major ones being limonene, (Z) and (E)-β-ocimene, dihydrotagetone, terpinolene, piperitone, peperitenone, E -caryophyllene and trans -sesquisabinene hydrate. The fourth instar larvae of Aedes aegypti (LC₅₀ 13.57, LC₉₀ 37.91) was most susceptible to Tagetes patula essential oil followed by Anopheles stephensi (LC₅₀ 12.08, LC₉₀ 57.62) and Culex quinquefaciatus (LC₅₀ 22.33, LC₉₀ 71.89).

88, 89

Tamarindus indica

In Thai traditional medicine, the fruit of Tamarindus indica is considered to be as a digestive, carminative, laxative, expectorant and a blood tonic. A crude Tamarindus indica seed extract extract inhibited the PLA2, protease, hyaluronidase, L-amino acid oxidase and 5'-nucleotidase enzyme activities of Vipera russelli venom in a dose-dependent manner. Mice that received the extract 10 min after the injection of venom were protected from venom-induced toxicity. The seed coat extract of Tamarindus indica has antioxidant activity. The extract is composed of flavonoids including tannins, polyphenols, anthocyanidin, and oligomeric proanthocyanidins. These flavonoids may produce vasorelaxant activity, increase capillary permeability and protection from oxidative stress. Excess nitric oxide production is associated with diseases such as autoimmunity, rheumatoid arthritis, inflammatory bowel disease and septic shock. In vitro studies demonstrated that the crude seed coat extract of Tamarindus indica suppressed nitric oxide production while producing no adverse effects.

90, 91

Tournefortia hirsutissima

In Taiwan, Tournefortia sarmentosa Lam. is used as a detoxicant, an antiinflammatory agent, and a circulation promoter to remove blood stasis. Alkaloids, flavones, triterpenoids, and cinnamates are found in the genus Tournefortia. The stems of Tournefortia sarmentosa contain five phenolic compounds as well as salicylic acid and allantoin. Tournefortia rufo-sericeae leaves contain pyrrolizidine alkaloids (5% of dry weight).

92, 93