a very high ability to recognize the ingredients used in their medicinal herbs. However, with the development of modernization, the loss of contact with nature has reduced the ability to identify medicinal plants. Ancient texts about herbal medicine are often translated and interpreted differently, and as a result, there are the same names for more than one plant and different names for one plant. This condition is increasingly tricky with language diversity and local dialects [17, 18].
The morphological similarity of plant parts causes misidentification of herbal raw materials. Faulty raw materials can occur either intentionally or unintentionally. Adulteration usually occurs concerning the material’s economic value, for example, by replacing authentic raw material with other similar plant species. Accidental mistakes can happen mainly because workers’ carelessness collects wild plants as raw material [19–21].
Nomenclature problems cause misidentification that often occurs. Local names of plants are often referred to for their traditional use. The local name also often causes mistakes in raw materials and becomes dangerous, especially when replaced by poisonous plants. For example, in Traditional Chinese Medicine (TCM), the name “Fangji” is used for the root of Stephania tetrandra S. Moore (Menispermaceae). This species originated from the northern part of China. The official name in Chinese Pharmacopoeia is “Hanfangji”. The name “Fangji” is also used for the roots of Aristolochiafangchi YC Wu ex LD Chow & SM Hwang (Aristolochiaceae) originating from the southern region. In pharmacopeia, it is referred to as “Guangfangji”, and contains nephrotoxic and carcinogenic acid derivatives [11].
Misidentification also occurs in different species of plants that have the same local name. The two species have different pharmacological activities so that their use will not achieving therapeutic targets. In Indonesia, Mesua ferrea is called “Nagasari”, or in India, it is called “Nagakeshara”, an herb used for heart tonic, cardiotonic, emenagogue, hypotensive, antispasmodic, antianaphylactic, and antiasthmatic. However, Calophyllumino phylum is also sold under the local name “Nagasari” or “Nagakeshara”. This plant is usually used for antiinflammatory and treatment of psoriasis [22, 23].
Hypericum androsaemum is traditionally used for its diuretics and hepatoprotectives. Due to high demand but not in abundant stock, the raw material of H. androsaemum on the market is often found mixed with other genera, which more abundant and cheap or sometimes accidentally mixed with Hypericum perforatum. The traditional medicinal ingredient in China for leg pain and anti-inflammation, Piper kadsura, is often replaced by Piper wallichii. Both species have morphological similarities, but P. waliichii has no medicinal value. The same case also occurs with oriental ginseng (Panax ginseng C.A. Meyer), which is often mixed or replaced with American ginseng (Panax quinquefolius). Traders are forced or deliberately replace the plant parts of the same species or replace them with other species, which have a lower pharmacological or not at all [24–27].
Misidentification cases also occurred in black cohosh plants (Actaea racemosa L., Ranunculaceae). This plant is a raw material for menopause therapy products. This product causes hepatotoxicity in consumers. Valid analysis methods can prove that products on the market do not contain the right plants [21, 28].
In traditional Chinese medicine, Marsdenia tenacissima (Roxb.) Wight et Arn. (Asclepiadaceae) is used to treat esophageal, gastric, lung, and liver cancer. The M. tenacissima is known by the local name as “Tong-guanteng” and is sold in dried, sliced, shredded, and processed forms so that it is often difficult to identify the plant. The M. tenacissima is often replaced with Telosma cordata (Asclepiadaceae) and Fissistigma polyanthum (Annonaceae), which causes a poor therapeutic effect and even cause unwanted effects [14].
1.2.2 Variability of Chemical Content in Raw Material
Side effects of herbal product usage have been widely reported. These incidents are caused by mistaken authentication, adulteration, contamination by microorganisms or toxic chemicals, overdose, improper use, and interaction with drugs. There are still many raw materials of medicinal plants obtained from wild populations. Whether intentional or unintentional, mistakes often occur in the harvesting process, causing raw material to be contaminated by other species or unneeded plant parts. The poor quality of finished products is caused by the use of raw materials of phytopharmaceuticals that do not have high enough quality standards. The quality of raw materials of medicinal plants is greatly influenced by various factors such as intrinsic (genetic) and extrinsic (environmental) factors during their growth, cultivation, harvesting, post-harvest process, transportation, and storage [8].
1.2.2.1 Intrinsic Factor
Plants synthesize secondary metabolites such as phytoprotein and phytoalexin to defend themselves from environmental conditions involving insects, plant microorganisms, and other plants. The secondary metabolites in plants can be manipulated using genetic engineering, to increase desirable production and reduce the undesirable compounds. The synthesis of flavonoids and anthocyanins is the first genetic engineering that has been successfully carried out because the biosynthetic pathway is well known. The results can be detected from changes in flower color. The indole terpenoid alkaloids pathway is an attractive target for genetic engineering because about 15 terpenoids, alkaloids, and indole terpenoid alkaloids have an essential role in anti-tumor alkaloids, vinblastin, vincristine, and camptothecin. The success of genetic engineering in the future achievement of the pharmaceutical industry is used for the expansion of new compounds with new activities. But in some cases, excessive gene expression occurs so that it does not reach the desired target compound [29].
1.2.2.2 Extrinsic Factor
The environment and habitat are external factors that affect the types, proportions, and levels of active substances of the widespread species. Biosynthesis of the active substances in a plant results from interactions between plants and the environment in a long evolutionary process. The research on Eucommia ulmoides Oliv. reported that the height of the location and the average annual temperature were highly significant with chlorogenic acid and flavonoids levels. The duration of yearly sunlight positively correlated with geniposidic acid but negatively correlated with geniposidic acid levels. Potentilla fruticosa L. in traditional Chinese medicine is used for detoxification and for treating diarrhea, hepatitis, rheuma, and scabies. The P. fruticosa grows in cool and high regions in the northern subarctic mountains. Liu et al. proved that altitude has negatively correlated with tannin content, whereas the length of annual sunlight and altitude has positively correlated with flavonoid levels and antioxidant activity. The average yearly temperature has negatively correlated with total phenolic levels, while altitude has positively correlated with total phenolic levels [30].
Ecological factors such as climate, geography, land, and topography can affect plants’ growth, development, reproduction, behavior, and distribution. To overcome these effects, plants can regulate the synthesis of secondary metabolites. Different ecological factors cause differences in plant quality when compared to the original area. Dendrobium officinale, one of the traditional Chinese medicinal plants, is used as a tonic, nourish the stomach, relieve throat inflammation, improve eyesight, and promote body fluid. The main ingredients of D. officinale are polysaccharides, alkaloids, and flavonoids. To meet market demand and keep the original plant, the study results indicate that this plant’s cultivation must fulfill the factors such as humidity, temperature, duration of sunlight, soil pH, nitrogen, and phosphorus content in the soil needed by the plant [31].
Plant interaction with their environment causes variations certain secondary metabolites’ classes’ composition and production. The composition of constituents can be used for characterization as chemical markers for plants that grow from certain geographical areas, which are harvested at certain seasons or certain ages, based on qualitative and quantitative analysis of its chemical
