Date Published: December 2, 2018
Author(s): Janaina K. L. Campos, Tiago F. da S. Araújo, Thaíse G. da S. Brito, Ana P. S. da Silva, Rebeca X. da Cunha, Mônica B. Martins, Nicácio H. da Silva, Bianka S. dos Santos, César A. da Silva, Vera L. de M. Lima.
Indigoferasuffruticosa Mill. (Fabaceae) is known as anil or anileira and also with other names, due to the production of a blue pigment, which is commonly used for yarn dyeing. It is distributed in some states of Brazil (Pernambuco, Paraíba, Mato Grosso, São Paulo, Bahia, Pará, and others) and is used in the popular medicine as a febrifuge, antispasmodic, diuretic, abortive, analgesic, purgative, or soothing agent against stomach and urinary problems, jaundice, and ulcers and also as an insecticide. In addition, I. suffruticosa can be used as animal feed. This review aimed at providing important data on the botanical, distribution, ethnopharmacology, phytochemical, pharmacological, and toxicity of I. suffruticosa based on the scientific literature. Information on I. suffruticosa was gathered via the Internet (from Elsevier, NCBI, and Sci-Hub) and libraries in the period from February to March 2016. More than 40 chemical compounds have been identified and a few compounds isolated, and the main origins are the essential oils, organic extracts, and aqueous extracts of different parts of the plant. I. suffruticosa and its active compounds possess wide pharmacological actions in the literature, such as anti-inflammatory, antibacterial, antifungal, antioxidative, antitumor, antimutagenic, anticonvulsant, gastroprotective, and hepatoprotective activities. Therefore, as an important traditional popular medicine, further studies on I. suffruticosa are required for the development of new drugs and therapeutics for various diseases.
Fabaceae, present in the Brazilian biodiversity, is considered the third largest family of plants, which has about 19,500 species , and it is divided into three subfamilies: Mimosoideae, Caesalpinioideae, and Papilionoideae, and it shows a common feature in almost all fruits and vegetables, known as pods . Papilionoideae is a subfamily with greater wealth in the Caatinga. Among diverse species, the Indigofera species is taxonomically present .
I. suffruticosa is described as a shrub plant, measuring 1 m to 2 m height, having branches pubescent, stem angular, of grayish color, pinnate leaves composed of 7–15 oblong or oval leaflets, hairless on the face and back, with small flowers, numerous albo-pink or yellow, in axillary racemes, and its fruit is a small sickle pod with 6–10 seeds measuring 25 mm in length . Having strong adaptability, they are considered wild plants that grow in all types of soils, tolerating drought, floods, and high salinities.
Indigofera suffruticosa is popularly known as “indigo” or “anileira.” Such a nickname comes from the German language, meaning “blue pigment,” which is extracted through fermentation by hot infusion of its leaves and was used in the textile industries to dye yarns. Currently, this extract is processed by industrial chemical processes, and the use of this plant in the textile industries was abandoned . I. suffruticosa may also be related to other popular names such as jiquilite, tzitzupu, indigo fields, anileira guinea, real anileira, caá-chica, caá-chira, timbó-mrim, timbozinho, and indigueira. The species is widely used in folk medicine to cure many health problems, with uses based on infusions and decoctions of different parts of this plant . They are attributed to this plant’s febrifuge, antispasmodic, diuretic, abortive, and analgesic properties against stomach and urinary problems, jaundice, ulcers and purgative, sedative, and insecticidal properties .
Several studies have identified and isolated some chemical constituents of I. suffruticosa, including flavonoids, alkaloids, coumarins, triterpenoids, and carbohydrates. Early investigations of the chemical components of I. suffruticosa were made by Miller and Smith, 1973, using seed extract, with a highlight of the rich presence of amino acids and possible toxic effects. According to the Natural Products Alert  and Chemical Abstracts, the phytochemical profile of this species reveals the presence of alkaloids, polyphenols, terpenoids, steroids, reducing sugars, proteins, and indigoids.
Studies using aqueous extracts obtained by infusing leaves of I. suffruticosa in acute toxicity in mice demonstrated the presence of deaths in the tested groups. Some signs of toxicity were noted after a few hours of intraperitoneal administration from a lower concentration to a higher concentration tested dose (2400 mg·kg−1): agitation, piloerection, exhaustion, sleepiness, irritability, and spasms. Also, it was found that the LD50 of the acute toxicity of the aqueous extract of leaves of I. suffruticosa made by infusion administered in different doses in mice showed no mortality during 72 h of observation .
Plants since ancient times have been used as medicine and have been daily providing inspiration for new research, aiming to highlight the diverse potential and expand the library of biologically active molecules.