**6.4** *Piper betle*

*P. betle* L. (Piperaceae) commonly referred to as Betel pepper, is an evergreen climbing shrub producing woody stems, 5–20 m long, and distributed in Southeast Asia—probably originally from Malaysia. It is traditionally used to cure cough, cold, pruritis, asthma and rheumatism [79]. Ethanol and aqueous extract of leaves at doses 100 and 200 mg/kg possesses anti-asthmatic activity on histamine induced bronchoconstriction in guinea pig and histamine induced dose dependent contraction of guinea pig tracheal chain [80].

## **6.5** *Lepidium sativum*

*L. sativum L*. (Brassicaceae) also referred to as Garden cress is a profuselybranched, erect, annual plant growing up to 80 cm tall [81]. It commonly grown in many regions of Saudi Arabia and the Eastern Province. The seeds are used to cure bronchitis, asthma, cough, and useful as abortifacient, antibacterial, aphrodisiac, diuretic, expectorant, gastrointestinal stimulant, gastroprotective, laxative and

*Medicinal Plants for Treatment of Prevalent Diseases DOI: http://dx.doi.org/10.5772/intechopen.82049* 

stomachic [82]. The bronchodilatory effect of ethanolic seed extract and ethyl acetate, n-butanol and methanol fractions, against histamine and acetylcholine induced acute bronchospasm in guinea pigs, exhibited significant inhibition of bronchospasm, with n-butanol fraction showing a significant (p < 0.001) protection comparable to the reference standards used in the study [83]. Rehman et al. [84] also confirmed the bronchodilatory effect of *L. sativum* crude extract by investigating the various pathways for its activity in airway disorders. It was revealed that, the extract's activity was mediated through a combination of anticholinergic, Ca++ antagonist and phosphodiesterase inhibitory pathways.

#### **6.6** *Curculigo orchioides*

*C. orchioides* Gaertn. (Hypoxidaceae) is a stemless evergreen perennial herb producing a cluster of leaves from the roots and spreading to form a clump. It grows up to 50 cm tall. It ranges from East Asia—South China, Japan, Indian subcontinent, Myanmar, Thailand, Cambodia, Laos, Vietnam, Malaysia, Indonesia, Philippines, New Guinea, W. Pacific. Alcoholic extract of *C. orchioides* rhizomes at doses (100–400 mg/kg) shows mast cell stabilizing and antihistaminic activity on Compound 48/80-induced mast cell degranulation and systemic anaphylaxis [85]. Also Pandit et al. [86] established the usefulness of the ethanol extract in treating asthma, as it was reported to exhibit significant relaxant effect (p < 0.01) at concentrations 100 and 25 μg/mL in isolated goat tracheal chain and isolated guinea pig ileum preparations respectively. In an *in vivo* study using histamine induced bronchoconstriction in guinea pigs, egg albumin induced passive paw anaphylaxis in rats and haloperidol-induced catalepsy in mice, there was significant (p < 0.01) protection at lower doses. Again, maximum increase in leucocytes and lymphocytes (99%) and maximum decrease in eosinophils up to 0% at dose 375 mg/kg p.o. was reported in milk-induced total leukocytes and differential leukocyte counts.

#### **6.7** *Casuarina equisetifolia*

*C. equisetifolia* L. (Casuarinaceae) also commonly known as Common Ru, is an evergreen tree with a finely branched, feathery crown usually growing from 6 to 35 m and 20–100 cm in diameter. The tree is widely planted throughout the tropics, and ranges from East Asia to Bangladesh, Myanmar, Thailand, Vietnam, Malaysia, Indonesia, Philippines, Australia and the Pacific [87]. The methanol extract of wood and bark (10–80 mcg/mL) exhibited a significant dose dependent (p < 0.05) antihistaminic activity by inhibiting the histamine induced contraction of trachea. The wood extract (100 mg/kg, i.p.) significantly reduced clonidine induced catalepsy (p < 0.05) and mast cell degranulation (p < 0.001) [88].

## **7. Conclusion**

All the plants reviewed exhibited potent activity confirming their various traditional uses and their ability to treat prevalent diseases. There is therefore the need to subject these plants to further studies, by isolating active compounds which can be processed into new and potent medicines and the need to study their mechanisms of action.
