Assessment of the Quality and Evaluation of the Antioxidant Potential of a Novel Sri Lankan Ayurvedic Polyherbal Formulation.

BACKGROUND: In Sri Lanka, a Polyherbal Ayurvedic Formulation (PHAF), which consists of powders of seven medicinal plants, is being trialed for use as an anti-inflammatory drug. In general, anti-inflammatory drugs have good antioxidant properties. Therefore, in the present study, an attempt was made to assess the quality and evaluate the antioxidant potential of PHAF. METHODS: Physicochemical parameters such as ash content, extractable matter, phytochemical screening for secondary metabolites, levels of heavy metals, and microbes were determined according to standard protocols. Antioxidant activity was evaluated using five in vitro assays: total polyphenolic content (TPC), total flavonoid content (TFC), ORAC (oxygen radical absorbance capacity), DPPH (1,1-diphenyl-2-picryl-hydrazyl), and ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt. RESULTS: PHAF contained 5.6 ± 0.2% of moisture, 6.5 ± 0.1% of total ash, 1.4 ± 0.1% of water soluble ash, 0.9 ± 0.0% of acid insoluble ash, 7.7 ± 0.2% of hot water extractable matter, 3.9 ± 0.1% of cold water extractable matter, 10.5 ± 4.1% of hot-ethanol extractable matter, and 8.4 ± 0.2% of cold-ethanol extractable matter. Phytochemical screening revealed the presence of phenolic compounds, tannins, flavonoids, coumarins, and saponins in both aqueous and ethanolic extracts of the drug. TPC, TFC, ORAC, DPPH, and ABTS of aqueous and ethanol extracts of PHAF were 103.65 ± 4.94 and 327.07 ± 9.65 mg gallic acid equivalents/g extract, 76.6 ± 5.83 and 224.6 ± 8.42 mg quercetin equivalents/g of extract, 481.11 ± 17.30 and 1481.44 ± 30.20 mg trolox equivalents/g of extract, 79.50 ± 4.42 and 227.17 ± 6.16 mg trolox equivalents/g of extract, and 198.20 ± 4.55 and 577.08 ± 5.48 mg trolox equivalents/g of extract, respectively. CONCLUSION: Ethanolic extract of PHAF is better than aqueous extract in terms of antioxidant properties.

Gastroprotective effect of Piper betle Linn. leaves grown in Sri Lanka.

BACKGROUND: Piper betle Linn. (Piperaceae) is used as a remedy for gastric ulcers in traditional medicinal systems in Sri Lanka. However, the gastroprotective activity has never been proven scientifically using betel leaves grown in Sri Lanka. OBJECTIVE: To evaluate the gastroprotective activity of hot aqueous extract (HAE) and cold ethanolic extract (CEE) of P. betle in rats as the experimental model. MATERIALS AND METHODS: Three doses (200, 300, and 500 mg/kg/bw) of both extracts were evaluated for the gastroprotective activity against ethanol induced gastric ulcers in rats. The parameters evaluated were (a) effects of HAE on mucus content adhering to the wall of the gastric mucosa, (b) acidity (total and free), (c) volume and (d) pH of the gastric juice. RESULTS: ORAL ADMINISTRATION OF HAE AND CEE PROVIDED MARKED DOSE DEPENDENT (HAE: r (2) = 0.97; CEE: r (2) = 0.96) and significant (P ≤ 0.05) protection against gastric damage caused by absolute ethanol. The gastroprotective effect of CEE was comparable with that of HAE. Further, gastroprotective activity of the highest dose of both extracts were significantly greater (P ≤ 0.05) than that of misoprostol, the reference drug. The HAE significantly (P ≤ 0.05) increased the mucus content adhering to the wall of the gastric mucosa and inhibited the volume of gastric acid. However, acidity (total and free) and pH of the gastric juice remained unaltered. CONCLUSION: It is concluded that both HAE and CEE of P. betle leaves have a strong gastroprotective activity.

Alpinia calcarata Roscoe: a potent antiinflammatory agent.

AIM OF THE STUDY: Alpinia calcarata Roscoe (Family: Zingiberaceae) rhizomes are often used in Sri Lankan traditional systems of medicine as a remedy for bronchitis, cough, respiratory ailments, diabetics, asthma and arthritis. Generally drugs that are used for arthritis have antinociceptive and antiinflammatory properties. However, validity of the antiinflammatory activity has not been scientifically investigated so far. Therefore, the aim of this study was to investigate the antiinflammatory potential of Alpinia calcarata rhizomes using hot water extract (AWE) and hot ethanolic extract (AEE). MATERIALS AND METHODS: The antiinflammatory activity of Alpinia calcarata was evaluated by use of the carrageenan-induced paw oedema model in rats. In addition, the mechanism/s by which Alpinia calcarata is mediated the antinflammatory activity was assessed by determining its effects on (a) membrane stabilizing, (b) antihistamine and (c) prostaglandin synthesis inhibition activity. RESULTS: All the tested doses of AWE and AEE (250, 500, 750, and 1000 mg/kg) produced a significant (P≤0.05) inhibition of the inflammation, most pronounced at 4h after the injection of carrageenan. The antiinflammatory effect induced by 500 mg/kg of AEE was superior than the reference drug, indomethacin at 4h. Inhibition of histamine and prostaglandin synthesis production is probable mechanisms by which Alpinia calcarata mediates its antiinflammatory action. CONCLUSION: These findings rationalize the traditional usage of Alpinia calcarata as an antiinflammatory agent for the first time.

Investigations on Piper betle grown in Sri Lanka.

Piper betle is an economically important plant cultivated in Sri Lanka. Although more than 12 cultivars of betel are reported in Sri Lanka, very few scientific investigations have been carried out on them. Studies on the chemical constituents indicated that safrole is the major constituent, followed by chavibitol acetate, in the essential oil of common betel leaves of Sri Lanka. Investigations on the bioactivities of P. betle revealed the presence of antimicrobial, insecticidal, antioxidant, antinociceptive, antidiabetic and gastroprotective activities. In addition, P. betle was found to be safe in terms of hepatotoxicity, renotoxicity, hematotoxicity, gross morphology, weights of organs, stress or aversive behaviors in rats. The above findings indicate the vast potential of P. betle yet to be harnessed for the benefit of mankind and the betel industry of Sri Lanka.

Gastroprotective activity of Trichosanthes cucumerina in rats.

AIM OF THE STUDY: The aim of the present study was to scientifically investigate whether Trichosanthes cucumerina Linn (Family: Cucurbitaceae) has gastroprotective activity. MATERIALS AND METHODS: All the experiments were conducted using Wistar strain rats (weight: 200-220 g). The food and water given to rats was withdrawn for 36 and 12h respectively, before the commencement of the experiment. These rats were randomly divided into 6 groups (n=8 rats/group; 4 males+4 females) and groups 1-3 were orally administrated with hot water extract (HWE) at a dose of 375, 500 and 750 mg/kg, respectively. Group 4 was orally treated with equal volume of distilled water (1 mL; control), group 5 was orally treated with a reference drug, cimetidine (100mg/kg) while the group 6 was orally treated with another reference drug, sucralfate (400mg/kg). In the indomethacin experiment, only one dose of HWE (750 mg/kg) was tested, as this was found to have the maximum effect in the alcohol model also. RESULTS: Results show that the HWE of Trichosanthes cucumerina possesses significant (P

Standardization of Alpinia calcarata Roscoe rhizomes.

BACKGROUND: Rhizomes of Alpinia calcarata Roscoe (Family: Zingiberaceae) possess several bioactivities and are used in the traditional medicinal systems of Sri Lanka. METHODS: The present investigation was carried out to standardize the rhizomes of A. calcarata by (a) screening for phytochemicals (b) determination of physico-chemical parameters and (c) development of a Densitogram. RESULTS: Phytochemical screening revealed the presence of polyphenols, tannins, flavonoids, steroid glycosides and alkaloids in A. calcarata rhizomes. The percentages of moisture, total ash, acid insoluble ash, water soluble ash, ethanol extractable matter and water extractable matter were of 5.5 - 6.8, 8.3 - 8.8, 0.036 - 0.040, 7.2 - 7.8, 22.6 - 24.8 and 18.6 - 20.5 respectively. CONCLUSION: The results obtained from this study can be used to standardize rhizomes of A. calcarata grown in Sri Lanka.

Antidiabetic activities of aqueous and ethanolic extracts of Piper betle leaves in rats.

Leaves of Piper betle (Piperaceae) possess several bioactivities and are used in traditional medicinal systems. However, its antidiabetic activity has not been scientifically investigated so far. The aim of this study therefore, was to investigate the antidiabetic activity of Piper betle leaves. This was tested in normoglycaemic and strepozotocin (STZ)-induced diabetic rats using oral administration of hot water extract (HWE) and cold ethanolic extract (CEE). In normoglycaemic rats, both HWE and CEE significantly lowered the blood glucose level in a dose-dependent manner. In glucose tolerance test, both extracts markedly reduced the external glucose load. The antidiabetic activity of HWE is comparable to that of CEE. Moreover, HWE failed to inhibit the glucose absorption from the small intestine of rats. Both extracts were found to be non-toxic and well tolerated after following chronic oral administration (no overt signs of toxicity, hepatotoxicity or renotoxicity). However, the weight of the spleen had increased in treated groups possibly indicating lymphoproliferative activity. It is concluded that HWE and CEE of Piper betle leaves possess safe and strong antidiabetic activity.

Antinociceptive activities of aqueous and ethanolic extracts of Alpinia calcarata rhizomes in rats.

Rhizomes of Alpinia calcarata Roscoe (Zingiberaceae) posses several bio-activities and are used in traditional medicine of Sri Lanka. However, their antinociceptive activity has not been investigated so far. The aim of this study therefore, was to examine the antinociceptive activity of hot water extract (HWE) and hot ethanol extract (HEE) of Alpinia calcarata rhizomes using rats and three models of nociception (tail flick, hot plate and formalin tests). Different concentrations of HWE (100, 250, 500, 750, 1000 mg/kg) and HEE (100, 250, 500, 750, 1000 mg/kg) were made and orally administrated to rats and the reaction times determined. The results showed that the extracts have marked dose-dependent antinociceptive activity, when evaluated in the hot plate and the formalin tests but not in the tail flick test. The antinociceptive effect was slightly higher in HEE than that of HWE. The antinociceptive effect was mediated via opioid mechanisms.