A SURVEY OF MEDICINAL PLANTS AROUND UPPER SONGKHLA LAKE, THAILAND

Background: Upper Songkhla Lake, a single lagoon of Thailand, is surrounded by sandy, mangrove, and swamp forests. Many plants growing in these areas have medicinal properties, however they have never been investigated. The aim of this study was to explore medicinal plants from upper Songkhla Lake, Songkhla and Phatthalung provinces. Materials and Methods: Semi-structured interviews were conducted with seven key informants to get information regarding the local names, parts and utilization, method of preparation, route of administration and properties of plants. Voucher specimens were prepared, identified and deposited. Results: In total, 95 species belonging to 82 genera in 46 families were found. Among them 26 groups of ailments could be classified, and most of the herbal plants were used for antipyretic (24.30%). Conclusion: It was found that the natural sources of medicinal plants were damaged by many human activities. Therefore, this compilation of medicinal plants will be the data evidence for further conservation of the plants.


Introduction
Thailand is situated in tropical area covered by biodiversity-rich resources.Approximately 10,000 species of vascular plants are found.Of these only 2% are utilized by Thai people (Santisuk, 1989), in which the most commonly used are medicinal plants (Anderson, 1993).
The medicinal plants are various plants having medicinal properties.It is known that many types of modern drugs have been derived and developed from medicinal plants according to folk wisdom of herbalists.Thereafter, the studies of folk medicinal plants have been interested from scientists worldwide with the hope that they will discover either new modern or folk drugs.In Thailand, several studies of medicinal plants of ethnic minority groups such as the Akha, Hmong, Lahu, Lisu, Mien, Karen, and Thai Song Dam (Anderson, 1993;Paisooksantivatana and Kako, 1996;Thongdonair, 2003) have been conducted.
Several communities in Thailand nurture rich knowledge about medicinal plants and its uses.However, only the local healers and elders know about their traditional utilization.Therefore, it is necessary to explore and gather knowledge concerning medicinal plants and disseminate to the public to promote the use of local and wild plants.
Upper Songkhla Lake is part of Songkhla Lake which is the largest natural water source of Thailand.Although it is widely called Lake, geologically it is a single lagoon of Thailand.The lake is surrounded by patches of discontinuous sandy, mangrove, and swamp forests (Greangkhajon, 2006).Up to now, the areas are occupied by local population and existing natural resources have been exploited by inhabitants (Sutiwipakorn, 2007).Nowadays, not only natural forests surrounding the lake is decreased, but medicinal plant diversity is declined due to damaging by human activities such as buildings, agriculture, and tourism.In contrast, the indigenous knowledge of plant utilization has never been explored.It is a necessity and urgent to record as quickly as possible all information about plants and the role of people in conserving them.
This research aimed to explore species and utilization of medicinal plants from the upper Songkhla Lake.This study would be the basis for developing primary health care by using herbal plants.

Methodology Study area
Upper Songkhla Lake (Fig. 1), also known as Thale Luang, is situated between Thale Noi, Phatthalung province in the North and Koh Yai, Krasaesin district, Songkhla province and Ban Laem Chong Thanon, Khao Chaison district, Phatthalung province in the South, covering a total area of 460 square kilometers with approximately 2 meters depth.The lake contains freshwater but can be salty in dry season.Presently, it is believed to be the habitat of Irrawaddy dolphins (Sutiwipakorn, 2007).The area is inhabited by estimated 276,927 people who are mostly Buddhist.Most of people make a living on paddy farming, rubber plantation, orchard, and fishery (Research and Development Office, Prince of Songkla University, 1994).
In this study, the survey was carried out in the accessible area of swamp forests and sandy forests in four districts including Ranode and Krasaesin in Songkhla province (2 swamp and 4 sandy forests) and Mueang and Khao Chaison in Phatthalung province (2 swamp and 4 sandy forests).

Field study
There were seven key informants (2 from Phatthalung province and 5 from Songkhla province) who have experience on folk medicine of at least  The field studies were conducted during June 2012 to January 2013.The semi-structured interviews were used for information on local names, parts and utilization, method of preparation, route of administration, and properties of plants.The folk healers were interviewed at their houses and also during field survey.For reliable information, consistency of any use by at least 2 informants was recorded.

Herbarium specimens
All medicinal plants used by the local healers were photographed and collected for preparing voucher specimens according to the methodology suggested by Chayamarit (1997).The voucher specimens were deposited at the herbarium of Faculty of Traditional Thai Medicine, Prince of Songkla University.

Plant identification
The collected specimens were identified based on taxonomic literatures such as Flora of Thailand, Flora Malesiana, and Flora of China.

Data analysis
The data were analyzed by descriptive statistics and interpretation.

Diversity of medicinal plants
Totally, 95 species belonging to 82 genera in 46 families were collected as medicinal plants (Table 1).Most of the medicinal plants were found in Phatthalung.From the investigation, it shows that study sites from Phatthalung are more fertile than the area in Songkhla province resulting from the less destroyed farmsteads from human activities.According to habitat, plants from sandy forests were found more species than swamp (71 and 28 species respectively).This result is consistent to the study from nearby area, Sating Phra peninsula, Thailand (Neamsuvan et al., 2012) which revealed more plant species from beach forests than wetland areas.
The most frequently used plant families were Fabaceae (14 species), Asteraceae (7 species) and Euphorbiaceae and Malvaceae (5 species each).It is consistent with the world large plant families with ranking of Asteraceae and Fabaceae in the top five groups (Clayton and Renvoize, 1986).This result depicts that people likely to use natural resource in their circumstance (Neamsuvan et al., 2012).In addition to favorite family, Euphorbiaceae is one of widely distributed family, and it is worldwide important medicinal plants (Mwine and van Damme, 2010).
There were five plant habits found in this study.Herbs were most frequently used with 39 species (39%) followed by trees with 24 species (24%), climber with 20 species (20 %), shrubs with 16 species (16%), and epiphytic plants with one species (1%).Most use of herbs and trees (Thao khan) P, So Sw,Sa C 1) whole plant/ decoction/ oral (drink)/ prickly heat, joint and muscle pain 2) fruit/ decoction/ oral (drink)/ blood tonic, expectorant NS069 conforms to species diversity of these habits found in adjacent area, Thale Noi wetland (Bunpapong, 2000).In addition, herbs were frequently used probably due to their simplicity of harvesting.

Ailments treated
All 95 medicinal plants were grouped into 26 categories based on ailments treated.Fever was the largest group with 37 species (24.03%), followed by joint and muscle pain with 15 species (9.74%) as well as skin diseases with 14 species (9.09%) (Table 2).
Fever, also known as pyrexia, is one of the common medical signs with high body temperature, fatigue, and headache.Based on the interviews, the examples of medicinal plants are capable of reducing those symptoms including Alternanthera bettzickiana (Regel) Nichols., Pluchea indica (L.) Less., and Crateva magna (Lour.)DC.Traditionally, it is believed that medicinal plants for fever are bitter, cool and tasteless (Bureau of Sanatorium and Art of Healing, 1998).The plants used by local healers conform to those from Thai medicinal theory.
Joint and muscle pain is a group of symptoms could be found in all ages.It is caused by wrong movement or physical signs of some diseases such as knee pain, muscle pain from fever or paralysis.In Thai medicinal theory, it is caused by muscle and tendon contraction which badly effect to blood circulation (Bureau of Sanatorium and Art of Healing, 1998).The medicinal plants to get rid of those symptoms namely, Croton caudatus Geiseler., Sennatora (L.) Roxb.and Derris scandens Benth are used.
In folk medicine of Thailand, there is doctrine of signature that climber plants tend to be drugs for joint and muscle pain.This result is concordant to that belief.Derris scandens Benth., Tetracera loureiri (Finet et Gagnep.)Pierre ex Craib and Lablab purpureus (L.) Sweet are climbers and are used for healing the symptoms.Phyllanthus amarus Schum & Thonn. is used to treat fever, diabetes as well as high blood pressure.The similar uses between related studies show reliable uses of plants.

Medicinal plants for the first report
There are 6 herbal species that had never been reported for their folk use before.They are included whole plant of Indigofera tinctoria L. for itching skin; roots of Gomphrena celosioides Mart.for blood circulation in postpartum women; whole plant of Ipomoea sagittifolia Burm.f. for gastric ulcer and abscess; Stenochlaena palustris (Burm.f) Bedd.for fever; charcoal of Sonneratia ovata Backer for aches of bone and leaves of Scolopia macrophylla (Wight & Arn.) Clos.for muscle pain.These plants should be further studied in biological activities to confirm local utilization.

Biological activities
From literature reviews, 39 herbal species have their folk properties consistent to biological activities (Table 5).For example, Momordica charantia L. is locally used to treat diabetic and its biological activity for Anti-diabetic (Raman and Lau, 1996).Tiliacora triandra (Colebr.)Diels. is locally used for fever and its biological activity for anti-malaria (Saiin and Markmee, 2003).These consistent biological activities assist to confirm the healers' folk knowledge and get widely accepted from patients.

Comparison to PROSEA (PROSEA Foundation, 2006)
PROSEA (Plant Resources of South-East Asia) is Cooperation among Southeast Asian countries to collect information on plant resources for both academic research and industrial applications.Therefore, PROSEA is a project that promotes the sustainable use of plant resources.From comparison, it was found that 20 species corresponds to PROSEA (Table 6).For example, Cardiospermum halicacabum L., Cassia alata (L.) Roxb.and Melastoma malabathricum L. are used to treat fever, constipation and diarrhea, respectively.Comparison to PROSEA supports that the southern Thai utilization is reliable data and also suggests that some kinds of uses are transferred outside Thailand.

Interesting plants for promoting
Lumpeng (Stenochlaena palustris (Burm.f) Bedd.), the plant grows sparsely along swamp forest it is medicinal plant for antipyretic.In addition, it can be taken as vegetables in various traditional dishes belonging to southern Thailand.However, it is not widely used and the natural abundant is inadequate.Therefore, this species should be promoted for cultivation and consumption both inside and outsite the study area.

Conclusion
This study provides the folk knowledge of herbal utilization from upper Songkhla Lake.The data collected show that most of medicinal plants are used for antipyretic.Several plants have never been previously studied for their biological activities.Therefore, it is interesting to focus on these activities to confirm folk utilization of local healers.The treasure of knowledge is retained only by folk healers and medicinal plants are destroyed by human activities nowadays.Therefore, this compilation of medicinal plants will promote their practical use and be the data evidence for further conservation of the plants.
Neamsuvan et al., Afr J Tradit Complement Altern Med.(2015) 12(2):133-143 http://dx.doi.org/10.4314/ajtcam.v12i2.2013420 years and is accepted by local public health office were selected.At the beginning, all healers were informed with the purposes, method and expected outcome of this study.Verbal informed consent also was carried from participants.

Figure 1 :
Figure 1: Study area (A) Map of Thailand representing Phatthalung (a) and a part of Songkhla province (b) (B) Upper Songkhla Lake with studied districts from Phatthalung and Songkhla province

Table 2 :
Ailments treated by medicinal plants

Table 3 :
Plant part used

Table 4 :
Method of herbal preparation

Table 5 :
Biological activities reported