**2.5 Demographic data of informants**

In this study, 18 informants were involved, consisting of 12 men and 6 women. 4 informants came from Padang city, 3 from Padang Pariaman district, 3 from Pariaman city, 5 from Padang Panjang city, 2 from Bukittinggi city and 1 from Payakumbuh city. The highest number of informants is over 50 years old (**Table 1**).

From this research, it can be seen that older informants have more knowledge about medicinal plants than younger informants. This may be due to the lifestyle of the younger group which is more modern, they are not too interested in natural medicinal plants and prefer modern medicines obtained from doctors [3, 4].

Knowledge about the use of medicinal plants is largely derived orally (75%) from their ancestors, this type of inheritance method is common for traditional healers [5]. Thus seldom is there documentation for their practice and therefore there is an urgent need to document all information about the traditional practice of using medicinal plants especially for the treatment of growth determinants.

#### **2.6 Plant inventory**

There are 33 medicinal plants (**Figure 2**) that are believed by the local community as medicinal plants that can cure various diseases, a complete list of plants is presented in the **Table 2**. Local names, taxonomic names, parts used and method of preparation are also given.

### **2.7 Plant parts being used and preparation**

From the PPV (**Figure 3**) it was revealed that the leaves were the most widely used part, namely 58% followed by fructus 11%. The findings of this study are similar to those of other ethnomedicine studies [6–8], and most traditional healers use the leaves perhaps because it is relatively abundant and also to preserve and preserve medicinal plant species. Herb, direct eating (raw parts or juice) and direct use (crushed plant parts topically) are various methods used in traditional healing


#### **Table 1.**

*Informant demographic data (n =).*

*Ethnomedicine Study on Medicinal Plants Used by Communities in West Sumatera, Indonesia DOI: http://dx.doi.org/10.5772/intechopen.96810*

**Figure 2.** *Plant specimens.*


*Ethnomedicine Study on Medicinal Plants Used by Communities in West Sumatera, Indonesia DOI: http://dx.doi.org/10.5772/intechopen.96810*


*Abbreviation: ICS: Index of Cultural Significance; PPV: Plant Part Value; Fru: Fructus (Fruit); Sem: Semen (Seed); Tub: Tuber; Rhi: Rhizome; Cor: Cortex; Jui: Juice;* **Rad***: Radix (Root); Cau: Caulis; Dec: Decoction; De: Direct eat (raw part or the juice); Du: Direct use (topical).*

#### **Table 2.**

*Medicinal plants.*

**Figure 3.** *The percentage value of the plant part.*

for medicinal plants. Decoction of plant parts is the most commonly used method followed by direct consumption of plants (raw or juice parts).

This study aims to document and quantify medicinal plants used by communities in West Sumatra, Indonesia. The plant species collected from this study are mostly common medicinal plants used by traditional healers and are frequently documented in ethnobotany studies in Indonesia [9–13].

#### **2.8 Quantitative analysis of ethnomedicine data**

#### *2.8.1 Cultural significance index*

The significance value of plant species in the study area is calculated using the following formula:

$$I\text{CS}\sum\_{i}^{n} = \mathbf{1}\left(q \times i \times e\right)ui$$

Where q is the quality value for each species (1-5), I refer to the intensity value and e is the exclusivity value. The results obtained from the ICS calculations are then categorized based on the value proposed by Turner [14] shown in **Table 3**.


#### **Table 3.**

*The ICS value was proposed by Turner [14].*


*Ethnomedicine Study on Medicinal Plants Used by Communities in West Sumatera, Indonesia DOI: http://dx.doi.org/10.5772/intechopen.96810*


#### **Table 4.**

*ICS for each plant.*

## *2.8.2 Index of cultural significance (ICS)*

The index of cultural significance (ICS) is a reference used to calculate and predict the level of importance of a plant species in a certain area [14, 15], its value can be seen in **Table 4**. ICS analysis is usually carried out to calculate the usefulness of complete plants (food, medicine, rituals, construction, etc.) [14, 16], but because this study focuses more on medicinal plants that are trusted by the local community or known as ethnomedicine so for this study the only use calculated for medicinal purposes only.

Turner calculates the ICS value using the researcher's subjective allocation approach. Turner only uses three variables to calculate the ICS value, namely quality of use, intensity of use, and exclusivity of use [14]. The ICS value is obtained from the result of the multiplication of three variables when the calculation can also occur the addition of the product, this is done if a plant species has more than one use. Turner allocated 5 weight scales for the variables of use quality and intensity of use, namely 5, 4, 3, 2, 1 and allocated 3 scales for the use exclusivity variable, namely 0.5, 1, and 2.

From the research conducted and based on the mathematical calculation of the ICS value, it was seen that only two plant species had moderate significance (ICS = 30). The two plants that have ICS of moderate significance are red betel and soursop. These two plants are trusted by the public to prevent and treat cancer, so these plants are very popular and are considered important by the local community. As for the other plants, it is categorized as low significance. From the ICS calculation data, a plant for the local community can be used as raw material for medicine or herbal plants [17]. Although Turner's ICS ranks plant species used for food, especially staple foods, as the type of quality that has the highest score in determining cultural importance (CS).

### **3. Conclusion**

From the ethnomedicine research conducted, it is known that there are 33 plants that are used as medicinal plants by people in West Sumatra, Indonesia. Mostly, the plant leaves are used as raw material for medicine through direct consumption (juice of the plant parts) or by boiling, which is the most common way of preparation. Quantitative ethnomedicine data can be analyzed using the Index of Cultural Significance (ICS). To determine ICS, three variables are needed, namelyquality of use, intensity of use, and exclusivity of use.

#### **Acknowledgements**

The author would like to thank the Indonesian Ministry of Research and Technology for providing the budget through the Primary Research Scheme for Higher Education 2020-2022 and also to informants who have shared knowledge about medicinal plants.
