Swinglea glutinosa is a distinctive plant species and a member of the Rutaceae family, which also includes citrus fruits. It is recognized for its characteristics and historical uses. Exploring its natural form, preferred environments, and applications offers a deeper understanding of this plant’s significance.
Identifying Swinglea glutinosa
Swinglea glutinosa is typically recognized as a tree, potentially reaching up to 10 meters in height, and often features solitary spines on its trunk. Its leaves are trifoliate, meaning they are composed of three leaflets, with the terminal leaflet being larger, measuring about 6-12 cm long by 3-5 cm wide, while the lateral leaflets are smaller, around 2.5-5 cm long by 1.2-2.5 cm wide. The shape of these leaflets can be described as oblanceolate to elliptic. The plant produces small, white, and fragrant flowers. Following the flowering stage, it develops large, oblong-ovoid fruits that can grow up to 10 cm long and 6 cm wide. It is sometimes referred to by common names such as Glutinous Swinglea. The genus name honors Walter Tennyson Swingle, an American agricultural botanist known for his work on citrus classification.
Ecological Niche and Habitat
Swinglea glutinosa is native to specific regions of Southeast Asia, including the Philippines, India, Sri Lanka, and Myanmar. It thrives in tropical and subtropical moist lowland forests, indicating a preference for warm, humid climates. The plant can also be found in dry, rocky areas in India.
In Colombia, where it was introduced, it is widely cultivated as a hedge in rural and urban areas, demonstrating its adaptability. While some sources indicate its presence in Peru and Bolivia, where it prefers full sun and well-draining soil, its primary native distribution is consistently cited across Southeast Asia.
Traditional and Modern Applications
Historically, Swinglea glutinosa has found various applications, particularly in traditional folk medicine. In the Philippines, the juice extracted from its fruit is used to address skin complaints. This traditional remedy also extends to animal care, with the fruit juice being applied to help rid dogs of ticks.
Beyond medicinal uses, the plant holds value in horticulture. Its abundant foliage and alternate trefoil leaves make it suitable for ornamental purposes, such as its use as a defense fence or hedge in Colombia. Propagation of Swinglea glutinosa can be achieved through the division of offsets or by seed, with seeds sown in a well-draining, sandy soil mix and kept moist until germination.
Studies have indicated that extracts from this species possess anti-plasmodial properties, which could be relevant in combating certain parasitic infections. Furthermore, essential oil extracts from the plant have demonstrated in vitro anti-tuberculal activity, suggesting a potential role in developing new treatments for tuberculosis.
Key Compounds and Research Insights
Its diverse applications are attributed to its rich array of chemical compounds. Analysis of the plant has revealed the presence of various significant metabolites, including phenolics, such as flavonoids and phenolic acids, and non-phenolics like organic acids, amino acids, sugars, and fatty acids. For instance, hydroxylinolenic acid isomers and hydroxystearic acid, commonly found in the Citrus genus, have been identified in Swinglea glutinosa leaves and stems.
Specific studies have highlighted the presence of acridone alkaloids in the stem bark, roots, and leaves, while coumarins have been detected in its roots. Essential oils, severine alkaloids, and triterpenes have been found in its fruits, and amides were isolated from its stems and fruits.
The essential oil extracted from Swinglea glutinosa fruit, particularly from plants grown in Colombia, has shown antioxidant potential. Key compounds identified in this essential oil include sesquiterpenes like trans-nerolidol (up to 34.6%), nerolidyl acetate (9.8%), and germacrene D (4.8%), alongside monoterpenes such as beta-pinene (8.5%), alpha-terpineol (6.5%), and limonene (5.2%). These compounds contribute to its repellent activity against pests like the Tribolium castaneum weevil, indicating its potential as a natural biocide.