The Flora of the Philippines contains more than 12000 plant species, around 1500 of which are used by the traditional herbalists of the indigenous peoples in traditional medicine.1 Several medicinal plants have mechanical and chemical defense mechanisms that protect themselves from herbivores. These chemical compounds that deter herbivores have pharmacological effects against human diseases.2 Indigenous communities in the Philippines have been using plants as remedies for several diseases ranging from common ones such as headache, stomachache, cough, colds, toothache, skin diseases to more serious and fatal ones such as urinary tract infection, chicken pox, and dysentery.3
Ethnobotanical surveys were conducted in different Ayta communities in other provinces of Central Luzon such as Pampanga. A study conducted by Ragragio et al.4 documented that Ayta communities in Porac, Pampanga still use plants as food and medicines. However, there are no published resources on the ethnobotanical knowledge of the Ayta groups in Bataan. The Ayta communities of the Bataan Peninsula are considered as the least known and researched Ayta group in Central Luzon, Philippines. The Ayta communities in Bataan continue to reside in their forested ancestral lands and extensively depend on forest resources for food and medicines.5 Indigenous people living near the forest and far from market town have higher levels of ethnobotanical knowledge compared to those living close to the market town.6
There were several bioactivity studies conducted on the indigenous plants used by Ayta communities in Bataan especially the Ayta from Sitio Kanawan, Morong, Bataan.7-9 These studies indicate that the indigenous plants from Bataan can be potential sources of bioactive compounds thus further warrant the need for extensive documentation of ethno botanical knowledge of Ayta communities in Dinalupihan, Bataan.
The traditional knowledge held by indigenous peoples is an important resource that should be conserved. This knowledge continues to decline through time and there are only few indigenous communities with wide traditional and botanical knowledge.10 In the Philippines, this knowledge is endangered by Western acculturation and modernization. The present study answers the need for systematic documentation the traditional knowledge of indigenous peoples before it is lost. This research documented the herbal medicines of the three Ayta communities in Dinalupihan, Bataan. Specifically, it aims to identify the species of these medicinal plants, determine which plant parts are used for medicinal purposes, preparations and mode of administration of these plants and identify the most important species and calculate the informant consensus factors.
MATERIALS AND METHODS
The ethnobotanical survey was conducted in the Ayta communities located in three rural barangays in Dinalupihan, Bataan namely Payangan, Tubo-Tubo, and Bayan-Bayanan during December 2015. Dinalupihan is located 95 kms east of Manila with the geographical coordinates of 14° 52’ 34” North, 120° 27’ 45” East (Figure 1).11 It has a total land area of 92.52 km2. As of May 1, 2010, the total population of Tubo-tubo is 342, Payangan is 554 and Bayan-bayanan is 447. It has a tropical climate with significant rainfall almost throughout the year. It is considered as an agricultural town whose main resources are palay, sugar cane, corn, root crops, legumes and fruits including livestock and poultry.12
Data were collected through a semi-structured interview of 26 Ayta informants who are knowledgeable on medicinal plants. Informants were composed of the tribal chieftains, traditional healers and community elders. This semi-structured interview was composed of questions on medicinal plants, its utilization as traditional medicine, the diseases treated by the plants, the plants used for various diseases the parts that are used, how the parts are prepared and the frequency of use of these plants.
Ayta communities in Bataan has two languages, Filipino and their ethnic language which is Ayta Ambala. The older generations are fluent speakers of their ethnic language while the younger generations are more accustomed to speaking the Filipino language. Few Ayta hold leadership position in the community and the municipality of Dinalupihan. Majority of the Ayta in Dinalupihan, Bataan rely on farming for their living. They have fruit and vegetable plantation in the mountains and they sell their agricultural produce in the lowland markets. All of the Ayta communities have health centers but doctors and midwives only visit them once a week. The district hospital is far from their communities especially for those living in the mountains, thus people first consult traditional healers for common diseases.
Free and prior informed consents were obtained from all the informants. Permits were obtained from the chieftains and council of elders of the three Ayta communities in Dinalupihan, Bataan. The data were collected from 26 key informants composed of tribal chieftains, traditional healers and other elders through a semi-structured interview.13 This semi-structured interview consisted of questions on their knowledge about medicinal plants, the diseases treated by the plants, parts that are used, how the parts are prepared and administered for medicinal purposes. The key informants also collected the plants which were used for taxonomic identification and part of the field collection of the researchers.
Samples of the functional parts of medicinal plants were collected for taxonomic identification. The habitat, morphological characteristics, and reproductive parts of the plants were photographed and noted. Voucher specimens were preserved by immersing them in denatured alcohol and were sent to Mr. Danilo Tandang, botanist and researcher at the National Museum of the Philippines for identification and authentication. Scientific names of plants were determined and validated using The Plant List database.14
The information on the Ayta individuals (socio-demographic data) and on the medicinal plants based on the interview was tabulated. Two values were calculated to quantify the ethnobotanical data gathered: the Use Value (UV) and the Informant Consensus Factor (FIC). The Use Value is defined as the ratio of the number citations per species (U) to the number of informants (N) and is given by the formula: UV = U/N.13 High UV indicates high use-reports for a plant implying its relative importance to the local community. Low UV indicates few reports related to its use.15 Informant Consensus Factor, on the other hand, is evaluated using the formula: FIC = (Nur – Nt)/ Nur – 1: where Nur is the number of use-reports in each category and Nt is the number of species used for a particular category by all informants4. The maximum value attained in this Formula, 1, means that the informants completely agree that the particular species cited could cure a particular ailment. A value of 0, the minimum value, means that there is no exchange in information among the informants about plants.16 This simply means that the higher FIC value, the higher the possibility that the medicinal plants cited are the ones commonly and consistently used by the Ayta and assumed to be effective in treating a certain disease.17
RESULTS AND DISCUSSION
Profile of the Informants
A total of 26 informants from three barangays participated in the ethnobotanical surveys (Table 1). The informants were selected because of their knowledge on the medicinal plants they used. Ayta belonging the age group 46 years old and above have the highest number of informants for this ethnobotanical survey. The average number of plant species cited by all of the Ayta informants is 25.
|Barangay (Village)||Number of Respondents||Age (average)||Gender||Educational Attainment||Job|
|16-25||26-45||46 – up||M||F||E||H||C||BC||WC||Unemployed|
M – Male, F – Female, E – Elementary, H – High school, C - College WC – White collar (professional, managerial and administrative work), BC – Blue collar (perform labor jobs)
Differences in educational background as well as profession of informants did not have significant impact on the knowledge on indigenous medicinal plants. It was also observed in the survey that their knowledge of medicinal plans were passed down from their ancestors through oral traditions. When Ayta communities encounter diseases, they use medicinal plants first. When their herbal medicines can no longer cure the diseases, they use over-the-counter medicines or go to the district hospital for consultation and treatment.
The use of traditional medicine is an important part of healthcare of the Ayta communities in Dinalupihan, Bataan. The result of this study is limited because of the small number of Ayta informants. However, steps to ensure the reliability of informants for ethnobotanical studies were followed based on the recommendations of Tongco.18 This is very important in order to establish the reliability of the results even with low number of informants. The researchers made sure that the informants are reliable and competent in terms of their knowledge in medicinal plants. There were several consultations with the tribal leaders to identify key informants that will be included in this survey. Quality control was done to verify the data gathered during the interviews. After the completion of the study, the researchers went back to the three Ayta communities to verify the results and clarify several inconsistencies in the data gathered.
It was observed in this study that most of the traditional healers belong to the older generation. There were very few young Ayta who are knowledgeable about medicinal plants. This can indicate a decline in knowledge of the use of medicinal plants that pose a potential disappearance of this knowledge in the future. There were more women informants in this ethnobotanical survey compared to men. More medicinal plant species were cited by the women informants. This can be due to the fact that majority of traditional healers among Ayta communities in Dinalupihan were women. They are familiar with medicinal plants used against common diseases because they are usually left at home to take care of the children and the elderlies. Men usually go to the mountains to work in their agricultural lands.
Characteristics of Medicinal Plants
The list of medicinal plants obtained from ethnobotanical surveys are summarized in Table 2. Scientific and vernacular names, plant parts used, mode of administration and diseases treated were included in the list. A total of 118 plant species classified into 48 families have been documented to be used by the Ayta in the three communities (Figure 2). The most represented plant family is the Fabaceae family with 11 species, followed by Poaceae with 9 species, then Compositae and Lamiaceae with 8, Moraceae and Malvaceae with 5, and Anacardiaceae, Euphorbiaceae, Pandanaceae, Rutaceae, and Cucurbitaceae with 4 species each. The other 39 families have one to 3 representative species each.
Fr – Fruit, Lf – Leaf, Pe – Peel, Rh – Rhizome, Rt – Root, Se – Seed, Sh – Shoot, St – Stem
Family Fabaceae is the most represented plant family in this ethnobotanical survey with a total of 11 species used as medicines. This is similar to the results of Ragragio et al.4 in their study with the Ayta communities in Pampanga, Philippines. Family Fabaceae was also the most represented family in the Ayta of Pampanga with a total of fifteen species used as medicines. Another study conducted by Obico and Ragragio19 on the medicinal plants used by Ayta communities in Porac, Pampanga as insect repellant also observed highest number of species belonging to Family Fabaceae. Family Poaceae is the second family with the highest citation for medicinal use. Several study conducted in Northern Surigao del Sur and Bukidnon, Philippines also listed highest number of medicinal plants from Poaceae family.20,21
Collection Sites of Medicinal Plants
Medicinal plants are collected from the roadside and home gardens of Ayta (68%), mountains and wild habitat (21%) or both (11%) (Figure 3). Based on interviews with the traditional healers in Dinalupihan, most of the medicinal plants grow randomly along the roadside and backyard of the Ayta. They usually do not cut down the growing plants in their backyards and on the roadside because these plants constitute a source of medicinal plants that can be used to treat common diseases in their communities. Since most of the Ayta communities are located near the forest, they have an abundance of medicinal plants in their surroundings. Some of these medicinal plants are also cultivated
Ragragio et al.4 also noted that medicinal plants used by Ayta communities in Porac, Pampanga also came from kitchen garden and open fields. There are only few identified species that can only be found in the mountains. According to the Ayta informants, it was hard to find species that occur exclusively in the mountains especially those that are located in very steep mountainsides. Availability of the plants can be an important factor in their uses by the Ayta elders and healers as medicines.
Plant Part Used
Different parts of the plants are used for various diseases (Figure 4). Leaves are the most used plant part (43%), followed by the roots (18%), stem (15%), peel of the fruit (14%), skin of the stem (4%), flowers (2%) and seeds (1%). There are certain diseases that are treated with the whole plant. This accounts for 3% of the total plant species identified in this study and most are herbaceous plants.
Several ethnobotanical surveys conducted in the Philippines reported similar results with the leaves as the most frequently used plant parts.15,20,22One of the reasons for this is to protect the plants and ensure sustainability in the utilization of the plants. Harvesting the leaves are less destructive for the plants. Leaves are also easy to collect and are the most abundant plant parts. Secondary metabolites from the leaves exhibit toxic, repellent and/or anti-nutritional effects on the herbivores.23 These secondary metabolites such as alkaloids, saponins and phenolic compounds have exhibited antimicrobial and antifungal activities, which could be responsible for the pharmacological effects experienced by the Ayta communities.
Some of the plants listed by Ayta communities which utilized leaves for medicinal purposes include Psidium guajava which they use for the treatment of diarrhea, stomach ache, dizziness, toothache, cleaning of the uterus after pregnancy, phlegm, colds, indigestion, oral sores and wounds. Other ethnobotanical studies including one conducted in Kalinga, Philippines also used P. guajava leaves for the treatment of diarrhea, toothache and wounds.24 This plant is also included in the 10 medicinal plants endorsed by the Philippine Department of Health.
The roots are less used compared to the leaves since extraction of the roots is more destructive for the plants and the environment.24 Some of the medicinal plants that utilize roots as herbal medicines include Lygodium sp. which they use to treat nausea, headache, dizziness and kidney disease. Other ethnobotanical studies listed some species of Lygodium as medicinal plants however leaves are usually the most common plant part used. Lygodium japonicum is used by Kalanguya tribe in Ifugao for rheumatic attacks and relieves muscle pain.22 Another species of Lygodium lanceolatum is used in Southeastern Madagascar for the treatment of pancreas pain and gonorrhea.25
Preparation and Mode of Administration
The route of administration of these plants are also documented (Figure 5). The most common mode of administration is the oral route (drinking and eating) while the intravitreal administration is the least used mode of administration. Majority of medicinal preparations are taken orally (57%). Other routes of administration are dermal (36%) which includes rubbing and topical application on the affected part and traditional bath wash, nasal application (6%) which includes sniffing and smelling the aroma of the plant extract or the plant itself and (1%) intra¬vitreal administration.
Most of the medicinal preparations are taken orally (57%). This includes drinking decoction, eating and chewing fresh plants and gargling. This is congruent with other ethnobotanical surveys conducted in Bayabas, Sablayan in Benguet and Subanens in Dumingag, Zamboanga del Sur. Both previous studies noted that oral intake of decoction was the most common route of administration of medicinal plants. This involves boiling plant materials for a certain amount of time to soften the plants and extract its active compounds.3,26
The Ayta communities used both internal and external routes of administration to treat illnesses. Most of the plant species are used alone in treating diseases while there are few plants such as Citrus japonica Thunb. That are mixed with honey from bees and taken orally for treating cough and phlegm. Some plants such as Goniothalamus amuyon (Blanco) Merr and Solanum melongena L. that are used to treat arthritis and rheumatism and Sterculia foetida L. and Musa paradisiaca L., used to treat sprain are mixed with oils and massaged to affected parts of the body. G. amuyon and S. melongena have been previously reported as folk medicine for rheumatism. In Taiwan folk medicine, the seeds of G. amuyon are useful for the treatment of edema and rheumatism while S. melongena is useful for rheumatism, inflammation and foot pain.27,28
The use value of the plants were computed to quantify the importance of a specific plant based on how often it is cited by a specific number of people (Table 2). The lowest use value was calculated at 0.037 for 33 plant species with only one to two informants citing their medicinal use. It was found that P. guajava (Bayabas) and L. amara (Lunas Bundok) were the most important medicinal plants in the three barangays with a use value of 0.814.
The decoction of P. guajava are used by Ayta in treating variety of diseases such as diarrhea, stomach ache, dizziness, toothache, cleaning of the uterus after pregnancy to help the uterus to contract and avoid excessive bleeding, phlegm, colds, indigestion and oral sores. It is also the most commonly used plant in treating diseases of the digestive system including stomach ache, diarrhea and toothache and diseases of the respiratory system including common colds and acute upper and lower respiratory infections.
The decoction of stem, fruits and leaves of L. amara is used to treat stomach ache, colds, body pain, skin irritation, diarrhea, and dengue. It is the most commonly used plant for the treatment of skin irritation, common colds, stomachache, and muscle and body pain. In another study conducted in Agusan del Sur, Philippines, Manobo people and traditional healers reported using infusion of L. amara bark with with coconut oil and tinctured with wine. They rub these on the surface of affected or infected parts. These include treatments of wounds, allergies, skin infection and bites of dogs, snakes and insects. Oral intake of decoction of wine-tinctured bark or root of L. amara is used to treat stomach troubles, poisoning, ulcer, nausea, diarrhea, gastroenteritis and has antitoxin, antibacterial and antiviral properties.29
All plant species with the highest use values are used to treat wide variety of communicable (bacterial and viral infections) and non-communicable diseases. Artemisia vulgaris L., L. amara, P. guajava and Schizostachyum lumampao (Blanco) Merr. are used to treat sore throat, colds, cough and phlegm; Cordia dichotoma G.Forst. and P. guajava are used to treat wounds and infection and Cyanthillium cinereum (L.) H.Rob. is used to treat measles. Lygodium sp. is used to treat kidney disease, which is a non-communicable disease.
Informant Consensus Factor
Diseases mentioned by the Ayta informants were first classified according the International Disease Classification – 10.30 From these categories, FIC values were calculated (Table 3). The values ranged from as low as 0.659 to as high as 0.905. FIC values determine the consistency on the utilization of a plant species for a certain disease. Higher values indicated that only few plant species are used by the informants to treat a particular disease, whereas low values indicated low agreement on which plant to use for a specific disease.31
The highest FIC value (0.905) is for the diseases of the eye and the adnexa (sore eyes). The Ayta informants cited three plant species for the treatment of sore eyes. Tinospora rumphii Boerl. is the most commonly used plant for this disease category. Balangcod et al.32 reported the antibacterial activity of T. rumphii against Staphylococcus aureus which is a causative agent of bacterial conjunctivitis. The next highest FIC (0.875) was for the disease during the postpartum period. Vitex parviflora was the most commonly used plant for this disease category. The third highest FIC (0.858) was for the disease category for nausea, vomiting, dizziness and giddiness and fever. P. guajava was the most commonly used plant species for this disease category. A study conducted by Olorunfemi et al.33 observed central amelioration of pain sensation by the P. guajava stem bark in albino rats. This study showed a dose-dependent increase in central analgesic activities of P. guajava. It also showed synergistic analgesic activity when combined with morphine. Plants that are most utilized for diseases with high FIC values also have high use values.
Some of the plants used by Ayta communities as medicines were listed in the National list of threatened plants in the Philippines.34 Based on the, V. parviflora which is used for traditional bath after pregnancy, is classified as critically endangered species. On the other hand, Dracontomelon dao (Blanco) Merr. and Rolfe, which is used as treatment for wound infection, belonged to the vulnerable category.35 Excessive use of these medicinal plants coupled with the threats from deforestation, land conversion or agricultural expansion, and natural disasters may put these plants in the danger of extinction. This record of the medicinal plants used by Ayta communities further echoes the need to protect and conserve these medicinal plant species because of their environmental and medicinal importance.
This study showed that the three Ayta communities in Dinalupihan, Bataan use a total of 118 identified plants for medicinal purposes. This documentation of ethnobotanical knowledge provides a catalog of useful plants of the Ayta, and will serve as a physical record of their culture for the education of the future Ayta generation. It will also strengthen Ayta culture by recognizing their traditional knowledge on medicinal plants and providing scientific basis for it. This can help in preserving the traditional knowledge of the Ayta which is slowly fading away due to modernization and the influence of the non-Ayta communities. This study can also serve as baseline knowledge for future functional bioactivity screening of indigenous plants.