Traditional medicinal plants indigenous to Al-Rass province, Saudi Arabia

Man ever since his first appearance on Earth, has used plant throughout his historical development as a source of medicines. Medicinal plants have formed the basis of the folkloric medicine which was the main source for new medicines discoveries (Newman et al., 2000). By the middle of the nineteenth century at least 80% of all medicines were derived from plants. Then, after the scientific revolution which leads to development of the pharmaceutical industry, the synthetic drugs dominated (Gilani and Atta-ur-Rahman, 2005). Herbal drugs are prescribed widely because of their effectiveness, fewer side effects and are relatively low in cost (Odhav et al., 2010). Saudi Arabia has a hot desert climate and rainfall is scarce in most parts of the country. The flora of Saudi Arabia as well as the other countries in the peninsula has been neglected for a long time due to its arid climate. The first attempt to cover the flora of Saudi Arabia was in 1974 (Alfarhan et al., 1998). However, traditional medicine, occupies a significant part of Saudi Arabia’s heritage and it is widely practiced until now (Al-Essa et al., 1998). Al-Rass province is located in south west of Qassim area in the central area of Saudi Arabia, eastern to the Arabian shield far from Riyadh, the capital, about 400 km (El-Ghazali et al., 2006). The aim of this study is to investigate the ethnobotanical knowledge and its


INTRODUCTION
Man ever since his first appearance on Earth, has used plant throughout his historical development as a source of medicines.Medicinal plants have formed the basis of the folkloric medicine which was the main source for new medicines discoveries (Newman et al., 2000).By the middle of the nineteenth century at least 80% of all medicines were derived from plants.Then, after the scientific revolution which leads to development of the pharmaceutical industry, the synthetic drugs dominated (Gilani and Atta-ur-Rahman, 2005).Herbal drugs are prescribed widely because of their effectiveness, fewer side effects and are relatively low in cost (Odhav et al., 2010).
Saudi Arabia has a hot desert climate and rainfall is scarce in most parts of the country.The flora of Saudi Arabia as well as the other countries in the peninsula has been neglected for a long time due to its arid climate.The first attempt to cover the flora of Saudi Arabia was in 1974 (Alfarhan et al., 1998).However, traditional medicine, occupies a significant part of Saudi Arabia's heritage and it is widely practiced until now (Al-Essa et al., 1998).Al-Rass province is located in south west of Qassim area in the central area of Saudi Arabia, eastern to the Arabian shield far from Riyadh, the capital, about 400 km (El-Ghazali et al., 2006).The aim of this study is to investigate the ethnobotanical knowledge and its *Corresponding author.E-mail: emad100sdl@yahoo.com.applications of the medicinal plants indigenous to Al-Rass province.

MATERIALS AND METHODS
Several ethno-botanical field trips were carried out in different localities of Al-Rass province from October 2005 to April 2006.The information was gathered by ethnobotanical interviews with the local traditional healers or Bedouin who had knowledge of the curative properties of plants.Both were mostly old people (60 to 70 years old).The various data of local name, medicinal uses, parts of plant used, were recorded.Plants collected were identified by Gamal E. El-Ghazali (Taxonomist).Voucher specimens were deposited in the herbarium at "The Museum of Science", College of Science and Arts, Al-Rass, Qassim University.

RESULTS AND DISCUSSION
Drug discovery form traditional medicinal plants continue to provide new and important leads against various illnesses (Balunas and Kinghorn, 2005).Selection of plants based on ethnobotanical knowledge can also lead to discovery of promising new molecules with potential therapeutic activities which are waiting to be discovered (Hostettmann et al., 2000).The ethnobotanical investigation in Al-Rass province has revealed that, a total of 47 medicinal plant species belonging to 28 families are commonly used for various illnesses by local inhabitants and Bedouin (Table 1).Table 1 showed a considerable number of plant species used for various illnesses associated with gastrointestinal problems, pains, rheumatism inflammations, ulcers, respiratory, circulatory, urological and skin diseases, and somewhat fewer for toothache, diabetes, allergy and gynecology.The most mentioned medicinal plant families were Zygophyllaceae (5 species), Brassicaceae and Chenopodiaceae (4 species), and Poaceae and Asteraceae (3 species).All these families as well as other families mentioned in this study are already represented in Saudi Arabia flora (Batanouny and Baeshin, 1982;Alfarhan et al., 1998), medicinal applications of some of their members have been already reported (Rahman et al., 2003;Saganuwan, 2010;Khatibi et al., 1989).
Interestingly, most of these plants are not traded in the domestic markets in Saudi Arabia.Besides, the principal chemical compounds, active ingredients, mode of action and safety in many of these plants have not yet been explained appropriately and surly requires further research.From the interviews, it was found that the traditional medicinal knowledge is mostly monopolized by old men, reversal to some communities in Africa, South America and Pakistan where women mainly are experts in medicinal plants and its application (Matavele and Habib, 2000;Begossi et al., 2002;Tareen et al., 2010).In addition, this ethnobotanical knowledge is not passed from the older generations to younger generations and it may become wiped out soon; Since, most inhabitants especially the younger generations tend to visit the clinics and hospitals more often than old people and Bedouin.Moreover, those traditional healers are using wild herbs without any effort to cultivate these medicinal plants making them under threat from extinctiont.This requires more attention since more than 15,000 plant species may face extinction globally due to over harvesting and habitat loss (Saganuwan, 2010).

Conclusion
Although, there is growing interest in traditional medicinal plants in Saudi Arabia, most local inhabitants in Al-Rass province did not rely on the indigenous medicinal plants due to the good health care services in this area and interest only goes to the official herbal shops in towns.The findings of this study lends some support to the treasures of traditional medicine knowledge in this area, which can serve as a basis for further medicinal research.

Table 1 .
Ethnobotanical information of some medicinal plants from Al-Rass province.