Herbal Medicine Used in the Treatment of Human Diseases in the Rif, Northern Morocco

Abstract

Since the beginning of time, the Moroccan people have used many medicinal plants as a popular medicine to cure many human and livestock health problems. Yet, few studies have been carried in the past to properly document and promote traditional ethnomedicinal knowledge. This study was conducted out from July 1st, 2016 to July 30th, 2018 in the Rif; it was aimed to establish the list of medicinal plants, together with the association of ethnomedicinal knowledge. The ethnomedicinal data obtained were from 1000 traditional healers using semi-structured discussions, free listing, and focus groups. Family importance value, plant part value, fidelity level, the relative frequency of citation, and informant consensus factor were applied in data interpretation. Plant species were accumulated, and deposited at the Plant, Animal Productions and agro-industry laboratory, Ibn Tofail University. A total of 280 medicinal plants belong to 204 genera and 70 families were documented. Asteraceae with 29 species was the most used family in this study area. Rosmarinus officinalis L. (RFC = 0.189) was the species the most commonly prescribed by local traditional healers. Similarly, the leaf was the most useful part of the plant (PPV = 0.364), the most frequent affections were osteoarticular affections (ICF = 0.983), and the majority of herbal remedies were prepared from a decoction (38.6%). The results of the present investigation confirmed the presence of indigenous ethnomedicinal information of plant species in the Rif’s area to treat various disorders. More investigation on phytochemical, pharmacological, and toxicological should be considered to determine new drugs from these reported plants.

Introduction

Medicinal plants have been prescribed and used extensively for thousands of years to treat various disorders and ailments in traditional herbal medicine systems all over the world [1]. In all ancient civilizations and on all continents, we find traces of this use. Thus, even today, despite advances in pharmacology, the therapeutic use of plants is very present in some countries, especially in developing countries [2]. The World Health Organization (WHO) estimates that unevenly, 80% of the people from developed and developing nations depend on traditional medicines, especially on plant-based medicine in primary healthcare [3].

The use of plant species for healing purposes is a matter of culture and tradition in Morocco. It should be noted that for the primary health needs, a large portion of Moroccan people utilizes traditional methods of medicine to treat their diseases [3,4,5,6]. The inability of many developing countries to supply contemporary pharmaceutical medications [7,8,9,10,11,12], and the high cost of many drugs, has forced local communities to search for alternative products, such as medicinal plants, that have proven effectiveness and safety and are culturally acceptable.

The Rif region is one of the most biologically diverse regions in the Mediterranean, with some of the rarest biogeographical areas in the world and biodiversity of primary importance with many plants of therapeutic interest [13]. For this reason, this region is the source of many medicinal plants marketed throughout Morocco and abroad and the use of plants in herbal medicine is still very present in this region. On the opposite, data on medicinal plants in this region are rare and insufficient. To complete partial and fragmentary studies those have been carried out throughout the Rif [13, 14], Talassemtane National Park [15], and Tingitane Peninsula [16]. It is, therefore, necessary to undertake them to identify the local uses of plant species.

It is in this context that an ethnopharmacological study was carried out in the Rif, which has a lithological diversity, structural and floristic plants important enough to establish the catalog of medicinal plants used in the traditional treatment of diseases, especially herbal medicine, as an alternative to enhance, preserve and rationally use them.

Materials and Methods

Description of the Study Area

The current study was conducted out in the Tangier-Tetouan-Al Hoceima region (North of Morocco) where the Rif’s area was located. It extends between 34° and 36° of latitude in the North and 4° to 6° of longitude in the East. It is bounded in the North by the Strait of Gibraltar and the Mediterranean Sea, in the South by the Rabat-Sale-Kenitra region and Fez-Meknes region, in the East by the Eastern Region, and in the West by the Atlantic Ocean (Fig. 1). The total geographical area of the Rif is 11,570 km² and the population of the city is about 3,549,512 inhabitants with an average population density of 222.2/km² [17]. The population is mixed between Arabic and Amazigh ethnicity.

Fig. 1

The geographical position of the Rif region

The Rif is marked by Mediterranean weather with the highest temperature up to 45 °C during summer (July–August) and below 0 °C during winter (December–January) and the average annual rainfall ranges from 700 to 1300 mm which falls mainly between October and February [18]. It is mountainous with elevations ranging from 145 to 2456 (Jbel Tidirhine) meters above mean sea level and the area dominated by species such as Abies marocana Trab., Pinus halepensis Mill., Cannabis sativa L., Cedrus atlantica (Endl.) Quercus suber L., Quercus ilex L., and Quercus canariensis Willd. Principally families of Rif are very much dependent on subsistence farming, livestock, and to a more secondary space, from forest resources for their livelihood.

Methodology

Ethnopharmacological Survey

Ethnopharmacological investigations were carried out from July 2016 to July 2018 to collect information on medicinal plants utilized to treat multiple human sicknesses in the Rif region. In this work, the sample has been developed through a mode of probabilistic sampling random stratified [19, 20] non-proportional, it is divided into 28 strata, having concerned the cities, villages, douars, and souks weekly in the area of study. It is based on environmental factors (climate, soil, and altitude), vegetation, and the distribution of the population. The techniques employed for data collection were semi-structured interviews [21], open-ended, group discussion, free listing, and noted and recorded with a digital voice recorder. 1000 informants within aged 17–95 were randomly selected for interviews (cautery installer, farmers, elder people, bonesetters, herbalists, and therapists) in Rif (weekly markets, pharmacies, hospitals, houses, and mosques). By conducting a stratified random sampling [22], samples are then formed in each of the 28 strata, including seven urban communes: [S₁: Al Hoceim (40), S₁₂: Chefchaouen (40), S₁₅: Tétouan (40), S₁₉: Martil (40), S₂₀: Md’q (40), S₂₁: Fnideq (40), S₂₆: Tanger (41)] and twenty-one rural communes: [S₂: Ajdir (35), S₃: Izefzafen (30), S₄: Bni Hadifa (30), S₅: Targuist (40), S₆: Tizi n Tchin (30), S₇: Issaguen (34), S₈: Bab Berred (35), S₉: Cherrafate (30), S₁₀: Bab Taza (30), S₁₁: Derdara (29), S₁₃: Akchour (35), S₁₄: Fifi (30), S₁₆: Bni Karrich (40), S₁₇: Mallalyène (35), S₁₈: Zinat (36), S₂₂: Belyounich (35), S₂₃: Melloussa (39), S₂₄: Ksar Esghir (34), S₂₅: Bni Ouassin (36), S₂₇: Al Bahraouiyne (39), S₂₈: Jouamaa (39)] and they are put together to make up the overall sample of 1000 informants. Knowing that the number of people surveyed varies from one stratum to another depending on the abundance of medicinal plants sought (Fig. 2).

Fig. 2

Distribution of survey points at the study area level

The time spent on each interview was approximately 20 min to one hour. The information collected concerning the profile of the interviewee (age, gender, level of study, monthly income, family situation, and locality) and the ethnopharmacological data for each plant include the common local name, the route of administration, the method of preparation, the dosage, the part used, the condition of the plant used and the diseases treated “Appendix A”. The people in the Rif region speak Amazigh, Arabic dialects and therefore, interviews were conducted in Amazigh or Arabic dialects. All the documented data were later translated into English.

Vegetation data collection

Fertile specimens for the present study were collected in the field (197 plant species), in herbal stores (50 plant species), and at the homes of traditional healers (33 plant species) in the Rif. The informants were always provided with fresh plant material, either collected with them, by them, or available at their market stands (Fig. 3). Field observations were also used to record the habitat of each plant species with the assistance of local guides and interviewed informants.

Fig. 3

Type of sachets used to preserve collected plant species

Plant species identification, and deposition in Herbarium

Based on ethnopharmacological knowledge provided by our informants, plant specimens with their exact taxonomy were ordered alphabetically by ethnomedicinal uses, vernacular name, and family name. The identification and nomenclature of the collected material vegetal were done first in the field and completed at the Plant, Animal Productions, and Agro-industry Laboratory (Fig. 4). These plant species mentioned by the informants were taxonomically identified using floristic and taxonomic references, especially “The medicinal plants of the Morocco” [23], “List of vascular plants of Morocco tomes I and II” [24], and “Practical vegetation of Morocco” [25,26,27]. All voucher specimens have been preserved during documentation and deposited in the Ibn Tofail University, Morocco Herbarium for future reference.

Fig. 4

Plant samples collected in the field and kept in papers with their scientific and local name

Statistical Analysis

Ethnopharmacological data collected are recorded on questionnaire sheets to be analyzed, studied, and confirmed or overturned at the end. Then these data were registered and interpreted by Microsoft Excel 2010 and IBM-SPSS Statistics Base 21. A representative and the quantitative scientific method was applied to examine the socio-demographic data of the informants (ANOVA One-way and Independent Samples T-Test). Further, the recorded data were analyzed by various quantitative indices like family importance value (FIV), the relative frequency of citation (RFC), plant part value (PPV), fidelity level (FL), and informant consensus factor (ICF).

Family Importance Value (FIV)

The FIV identifies the significance of plant families. It is an indication of therapeutic importance that can be utilized in ethnobotany to assess the value of natural plant species. To determine family importance value, we adopt the following method:${\text{FIV}} = \frac{{{\text{FC}}_{{{\text{family}}}} }}{{N_{S} }},$ where FC_family is the number of informants mentioning the family and N_s = Total number of species within each family [28].

Relative Frequency of Citation (RFC) and Frequency (FC)

RFC is calculated by dividing FC by an entire number of interviewees in the research (N). The value of RFC for plant species is based on the citing portion of interviewees for every species. Relative Frequency of Citation was determined by applying the following formula [29]: ${\text{RFC}} = \frac{{{\text{FC}}}}{N}$ with (0 < RFC < 1).

Plant Part Value (PPV)

PPV was determined by applying this equation [30]: ${\text{PPV}} = \frac{{{\text{RU}}_{{{\text{Plant}}\;{\text{part}}}} }}{{{\text{RU}}}} ,$ where RU is the number of applications notified of total portions of the medicinal plant and RU_{plant part} is the number of uses reported per part of the medicinal plant. The part among the most important PPV is the most used by the informants.

Fidelity Level (FL)

Fidelity level is the rate of interviewees who mentioned the uses of certain medicinal plants to treat a particular disease in the study region. The FL ratio is determined using this equation [31]: ${\text{FL}} \left( \% \right) = \frac{{N_{p} }}{N} \times 100$, where N_p is the number of interviewees that require the application of a plant species to cure a special affection and N is the sum of interviewees that use the medicinal species as a drug to treat any given illness.

Informant Consensus Factor (ICF)

Informant consensus factor (ICF) was determined to investigate an agreement between the interviewees on the related remedies for each group of diseases [32] ${\text{ICF}} = \frac{{N_{{{\text{ur}}}} - N_{t} }}{{N_{{{\text{ur}}}} - 1}}$, where N_ur is the number of use-reports in each disease category and N_t is many species used. The values for the Informant Consensus Factor range from 0 to 1.

Results

Socio-demographic Data

A total of 1000 respondents were interviewed. Based on socio-demography, these participants were categorized into different classes as given in Table 1. Among the participants, 52.7% were females and the remaining were males 47.3%, with a sex ratio female/male of 1.11. From the total respondents, 76% were married, 10.8% divorced, 9.2% widowed, and 4% unmarried. In terms of age, the age groups of 40–60 were very high compared to other groups (47.6%). Just 30.6% were more than 60 years old, 21.4% were 20–40 years old, and 0.4% of informants were below 20 years old. Regarding educational status, the majority of respondents (69.1%) were illiterate, while (23%) and (6.7%) respondents attended primary and secondary school, respectively. Only 1.2% of respondents were attended higher education. Considering the income/month, most of the informants were unemployed (41.6%), while (38.6%) of these informants had low income/month level, (17%) with average level income/month, and (2.8%) with higher-level income/month.

Table 1 Demographic profile of informants interviewed

Table 2 Inventory of plant species used to treat digestive system disorders by indigenous people of Rif

Table 3 Inventory of plant species used to treat respiratory diseases by indigenous people of Rif

Table 4 Inventory of plant species used to treat cardiovascular diseases by indigenous people of Rif

Table 5 Inventory of plant species used to treat neurological diseases by indigenous people of Rif

Table 6 Inventory of plant species used to treat metabolic diseases by indigenous people of Rif

Table 7 Inventory of plant species used to treat genitourinary diseases by indigenous people of Rif

Table 8 Inventory of plant species used to treat dermatological diseases by indigenous people of Rif

Table 9 Inventory of plant species used to treat osteoarticular diseases by indigenous people of Rif

Most Represented Botanical Family and Their Family Importance Value (FIV)

The floristic analysis of the results obtained identified 280 medicinal species and subspecies belonging to 204 genera and 70 plant families were reported as having rich ethnopharmacological uses in the Rif to treat different human ailments. In terms of the number of species, it appears that the Asteraceae family is the most represented with 29 species or 10.36% of the catalog developed, followed by Lamiaceae (22 species), Fabaceae and Poaceae (21 species each), Apiaceae (17 species), Solanaceae (12 species), Brassicaceae (11 species), Asparagaaceae (10 species), Amaranthaceae and Cucurbitaceae (8 species for each), Rutaceae (6 species), Myrtaceae and Rosaceae with 5 species each. Besides, Anacardiaceae, Caryophyllaceae, Cupressaceae, Euphorbiaceae, Lauraceae, and Zingiberaceae are each represented by 4 plant species. The Apocynaceae, Malvaceae, Moraceae, Oleaceae, Papaveraceae, Pinaceae, Rubiaceae, and Tamaricaceae are represented by 3 medicinal species each, whereas the other families are those with at most one or two medicinal plant species. Based on the family importance value (FIV), the families most cited by informants are Amaryllidaceae (FIV = 0.104), Lythraceae (FIV = 0.103) Caryophyllaceae (FIV = 0.084), Apocynaceae (FIV = 0.079), Capparaceae (FIV = 0.073), Linaceae (FIV = 0.065), Rubiaceae (FIV = 0.063), Nitrariaceae, Rhamnaceae and Verbenaceae (FIV = 0.053), Rutaceae (FIV = 0.052) and Arecaceae (FIV = 0.049). The vernacular names, scientific names of documented species, their families, used parts, methods of preparations, FL, FC, RFC, and FIV were illustrated in Tables 2, 3, 4, 5, 6, 7, 8, 9.

Diversity of Medicinal Plants

To assess the relative importance of the reported plant species, the relative frequency of citation (RFC) was calculated from the informants' citations. In the present study, the highest value reported was 0.189, and the lowest value was 0.001 for each species as given in Tables 2, 3, 4, 5, 6, 7, 8, 9. In the current investigation, the highest RFC value was reported for Rosmarinus officinalis L. (RFC = 0.189), Thymus satureioides Coss. (RFC = 0.176), Dittrichia viscosa (L.) Greuter. (RFC = 0.165), Lawsonia inermis L. (RFC = 0.154), Arenaria rubra L. (RFC = 0.153), and Nerium oleander L. (RFC = 0.146). Meanwhile, 60 medicinal plant species scored the least RFC value, which is 0.001.

Habitat of Medicinal Plants

The present study showed that 165 medicinal plant species (59%) used by the Moroccan pharmaceutical medicines today are collected from the agriculture (cultivated) (Fig. 5), 101 species 36% were collected from wasteland (Fig. 6) (All lands affected by water erosion, wind erosion, floods, water-logging, soil salinization, and soil alkalization) and only 14 species (5%) were introduced by marketing in other regions.

Fig. 5

Cultivation of vicia faba L. in Izefzafen region

Fig. 6

Salsola kali L. in a wasteland of Tizi n Tchin

Medicinal Formulations Used During the COVID-19 Lockdown for Improving the Immune System

Medicinal plant species have a fundamental unit for use as alternative medicines systems in Morocco and are the basis for the discovery of natural ingredients for the development of therapeutic agents in pharmacology. The study conducted in the Salé region [33] shows that the local population uses some plants to prevent and treat the COVID-19, which was mentioned by the Moroccan Rif community. In Moroccan Rif, the uses of medicinal species have increased during the COVID-19 pandemic as a preventive behavior. Citrus limon (L.) Burm. f. has been used to relieve cough, and as an expectorant in bronchitis. Allium sativum L. Allium cepa L. and Zingiber officinale Roscoe are indicated for respiratory disease (cold and cough), and other symptoms related to influenza. Eucalyptus globulus Labill. is indicated for symptoms of respiratory disease (bronchitis, rhinitis), due to the presence of 1–8-cineol [34]. Indications of respiratory conditions: Foeniculum vulgare Mill. Plantago lanceolata L., Pimpinella anisum L., Silybum marianum L., Laurus nobilis L., Malva sylvestris L., Thymus vulgaris L., and Glycyrrhiza glabra L. are indicated by informants for cough associated with a cold, sore throat, fever laryngitis, and tonsilitis. Hedera helix L. is indicated as antispasmodic, other indications are anti-inflammatory, and in the treatment of flu and fever. Black seeds of Nigella sativa L. are globally known as a spice and as such as a food item.

The Fidelity Level (FL) of Medicinal Plants Reported

Fidelity level (FL) designates the choice for medicinal plants to be better for other species in the treatment of a particular ailment. The plant species that are extensively used by the indigenous inhabitants have more important FL values than those that are few popular. In this study, the FL ranged from 45.5% to 100% for medicinal plant use age. The study determined 240 medicinal plant species (85.71%) achieve the greatest fidelity level (FL = 100%) and the remaining 40 plant species achieve reasonable FL.

Disease treated and their ICF values

The results of the ICF calculation show that the value in our study ranges from 0.944 to 0.983 per uses categories (Table 10). Results revealed that the very best ICF (0.983) value was obtained for osteoarticular diseases with 867 use-reports for 16 plant species. It's followed by dermatological diseases (ICF = 0.981), neurological diseases (ICF = 0.974), genitourinary diseases (ICF = 0.973), metabolic diseases (ICF = 0.972), cardiovascular diseases (ICF = 0.968), digestive system diseases (ICF = 0.945), and respiratory system diseases (ICF = 0.944).

Table 10 ICF values by categories for treating human ailments in the Rif region

Plant Parts Used in the Study Area

In classical pharmacopeia, various parts of medicinal plants identified particularly the seeds, the leaves, the flowers, the fruits, the roots, or maybe the entire plant are exploited by the indigenous people of Rif. supported the plant structure value (PPV) index, the leaf has been reported because the dominant party within the preparation of the herbal remedy within the study area (PPV = 0.364), followed by seed (PPV = 0.226), whole plant (PPV = 0.097), flower (PPV = 0.073), fruit (PPV = 0.060), root (PPV = 0.051), bulb (PPV = 0.044), other combinations (PPV = 0.034), rhizome (PPV = 0.026), bark (PPV = 0.021), and stem (PPV = 0.006), respectively.

Method of Preparation and Administration of Plants

Indigenous people in the study area used many methods of preparation. The results showed that the majority of remedies were prepared from decoction (38.6%) and infusion (34%), followed by cataplasm (11.3%) cooked (7.6%) and raw (2.3%). The percentage of the other methods of preparation grouped (maceration, inhalation, fumigation) doesn't exceed 6.2%. The main solvent with the plant was water, but milk, butter, tea, and honey, cereal oils were also widely used ingredients. The route of administration in this study varies with the type of disease treated and the actual sites of the ailments. The result revealed that herbal medicine was administered through different routes. Generally, the majority of informants prepared remedies were applied mostly by oral (82.4%) followed by massage (6.3%), swabbing (5.2%), other modes of administration (3.4%), and rinsing (2.7%).

Discussion

As part of this study, our investigations identified 280 species and subspecies used for medicinal purposes. These medicinal species belong to 204 genera and 70 botanical families that have been used to treat different ailments in the study area. Among plant families, Asteraceae had the greatest number of species (29) followed by Lamiaceae (22 species), Fabaceae, and Poaceae (22 species each). The dominance of Asteraceae and Lamiaceae might reflect a wide variety of active ingredients in the species taxa belonging to these families and their availability, wider distribution, abundance, and richness in the study area. Besides, people of the area have a piece of high knowledge about plants from these families, i.e. they have been using these plants for many generations and hence the members of these plant families are well known to them. families groups with high species richness most likely contain a great diversity of morphological and chemical properties [35] (flavonoids, alkaloids, saponins, terpenes, coumarins, organosulfur compounds, glycosides, steroids, tannin, mucus, lignans, anthraquinones, aromatic constituents, phenolic lipids, carotenoids, steroids, and), from which potential multiple uses can be derived. These results are in general agreement with previous ethnobotanical inventories which indicated that the most prominent families were Asteraceae Lamiaceae, Fabaceae Poaceae, Apiaceae, and Solanaceae [2, 11, 12, 36,37,38,39,40].

Our quantitative analysis showed that the highest RFC was calculated for Rosmarinus officinalis L. (RFC = 0.189), Thymus satureioides Coss. (RFC = 0.176), and Dittrichia viscosa (L.) Greuter. (RFC = 0.165). Several studies about Rosmarinus officinalis L., with biological, pharmacological, and phytochemical approaches have been conducted and indicate anti-proliferative, anti-inflammatory, anti-bacterial, and anti-oxidant healing properties [41,42,43]. As this plant species is widely distributed in almost all Moroccan regions, including the study area, and is easily spread, it is frequently used and a widely available raw material. According to these results, it is recommended that medicinal species having high RFC values should be further screened in pharmacological, toxicological, phytochemical, and biological activities for any novel molecules or chemicals for treating various ailments. Moreover, these species should also be prioritized for conservation as their preferred uses may place their populations under threat due to over-harvesting. Furthermore, the ethnopharmacological plants with greater values of RFC confirm the fact that these plant species were well accepted to the largest of the autochthonous people [44]. Among the 280 medicinal plants, 86 species were used for the treatment of digestive system diseases, whereas 41 species were used to treat respiratory system diseases, 30 species neurological diseases, 29 species cardiovascular diseases, 29 species metabolic diseases, 27 species genitourinary diseases, 22 species dermatological diseases, and 16 species were used to treat osteoarticular diseases.

The fidelity level (FL) of each species is also evaluated from the available information. It indicates the informant’s choice for each ailment and the potential of the species related to the diseases as well. FL values in this study varied from 45.5% to 100%. The study determined 240 species of plants with an FL of 100%, even without considering plants that were mentioned only once for better accuracy, whereas below FL values are obtained for plant species that are employed for several purposes. This result means that the indigenous people tended to rely on one specific medicinal plant for treating one certain disease than for several illnesses. Consequently, plant species not previously studied and have maximum FL should be recommended for further study related to clinical practice [45].

The diseases treated in the Rif region were classified into 8 ailment categories. The highest ICF values were recorded for osteoarticular diseases (ICF = 0.983), followed by dermatological diseases (ICF = 0.981), and neurological diseases (ICF = 0.974). The least (0.944) ICF was associated with Respiratory system diseases. Ethnopharmacological studies have shown that in some parts of the world, osteoarticular diseases are a first-use category [7, 46, 47]. Osteoarticular diseases were prevalent in the study area which can be attributed to the limited availability of hygienic food mineral salts (calcium, magnesium, phosphorus) and vitamins (Vitamin D). Higher rates meant that only a few medicinal plants are used by the interviewees to treat a particular disease. The plants frequently used to treat these disorders might contain active ingredients and thus were well known by locals. It expresses the best consensus between medicinal plants and treated osteoarticular diseases because informants interviewed used specific plant species commonly for osteoarticular diseases. Hence, species with high ICF values show that the plants traditionally used to treat these illnesses are worth exploring for bioactive compounds [48], while low values are associated with many plant species with an almost equal or high use reports suggesting a lower level of agreement among the informants on the use of these plant species to treat a particular disease category [39].

The Rifain people used many various plant parts for preparing remedies. In our investigation, leaves were the most commonly utilized plant part with PPV = 0.364 application in traditional medicinal remedies, followed by seed (PPV = 0.2263), and whole plant (PPV = 0.097). Many studies conducted elsewhere in other countries also showed the dominance of leaves in the preparation of remedies [1, 2, 4, 37, 49,50,51]. The reason why leaves and aerial parts were mostly used could be that they are most easily accessible and their richness in secondary metabolites produced by photosynthesis. From the conservation point of view, the use of leaves is sustainable, since, if the withdrawal of aerial parts is not excessive, will not prevent the development and/or reproduction of the plant [52]. In this context, the use of leaves in herbal preparations implies a more sustainable practice but the harvesting of roots (which oftentimes requires uprooting) may result to plant death [53]. On the other hand, collecting leaves has a less detrimental impact on plants compared to the harvesting of roots and stem barks especially where there are no sustainable harvesting strategies in place [54]. Besides, a collection of leaves would be much easier and sustainable than that of roots or flowers [55].

Concerning the methods of preparation, decoction (38.6%), and infusion (34%). are the most common preparation methods that are used by indigenous people of Rif. The major solvent with the plant was water, but milk, butter, tea, and honey, oils were also extensively used as ingredients. Local people of Rif add honey, sugar, salt, orange peel, banana, or lemon to increase the palatability of a preparation. Moreover, honey is considered sacred to Muslims and occupies an important place in Islamic popular medicine [56, 57]. Indeed, honey is considered an instant energy source and is often used in all parts of the world to improve the acceptability of medicinal plants having a bitter taste unbearable. The decoction is a mostly used method for the preparation of indigenous herbal practices due to its easy preparation by mixing with water or tea [58]. However, the decoction provides assemble the greatest for the active constituents and attenuates or eliminates the toxic effect of some compounds. Decoction and infusion are very valued and often favored by popular healers in Morocco [4, 7, 15, 59, 60]. The predominance of decoction of the different plant species in the Rif is in total agreement with most of the carried out ethnobotanical studies [4, 50, 51, 61,62,63,64]. Generally, the main route of application for herbal therapies was oral (82.4%). Furthermore, the oral mode of administration is a preferred route all over the world [10, 14, 36, 38, 39, 65]. The predominance of oral treatment may be explained by a large incidence of internal illnesses in the Rif region. The administration of oral treatment may be defined by a high degree of internal illnesses in the region [66].

Conclusions

Our investigation revealed that the use of plant species is playing an essential purpose in satisfying the basic healthcare requirements of the indigenous people residing in the Rif, northern Morocco. In this study, an ethnopharmacological catalog constituted of 280 plant species, belonging to 204 genera in 70 families, has been developed, these results of the study showed that there is a great variety of medicinal plants. The number of medicinal plants recorded for the prevention and therapy of human ailments is a good indicator of the potential that exists locally so long as the scientific procedure is added to the indigenous knowledge in terms of traditional herbal medicine. In light of this, medicinal plants with the most important RFC and FL values were identified could be taken up for further phytochemical, pharmacological, and clinical studies that allow the development of new herbal preparations or formulation of novel drugs addressed to improve the quality of life for treating various human diseases.

Appendix A