A comprehensive Review of the Phytochemistry, Pharmacology, and TherapeuticBenefits of Cuscuta reflexa Roxb

Introduction

Cuscuta reflexa (family Cuscutaceae) is a perennial, parasitic, leafless plant (Fig 1) which is rampant in tropical/sub-tropical but rare in temperate regions.^1,2 In India, it is mainly found in the Bengal plains, Western Ghats, Satara, Uttar Pradesh, Himachal Pradesh, and Uttarakhand.³ Although it is commonly called dodder, it is known by several names such as Akashbel, Swarnalata, Akakhilata, Devils gut, Hell weed, etc.⁴ The parasitism of C. reflexa is by wrapping itself around the host plant after attaching to it. If the host contains food beneficial to C. reflexa, it produces the haustoria inserting themselves into the host’s vascular system.⁵ This plant is an extensive climber andparasitic on different plant species such as alfalfa, chrysanthemum, clover, potatoes, trumpet vine, etc.⁵

Taxonomic classification:¹

Kingdom          Plantae

Subkingdom    tracheobionta

Superdivision   spermatophyta

Division           Angiospermes

Class               Eudicots

Subclass         Asterids

Order             Solanales

Family           Cuscutaceae

Genus            Cuscuta

Species          reflexa

Vernacular names: ¹

Tamil             Verillakothan

English          Dodder plant

Hindi             Amarabela

Sanskrit         Akasavalli, Amaravalli, Khavalli

Punjabi          Zarbut

Malayalam     Moodillathali

Urdu              Akashbel

Bengali          Akashbel

A literature search of various databases such as PubMed, Google Scholar, ScienceDirect, etc., was performed for articles on Cuscuta reflexa Roxb, specifically pertaining to its traditional usage. The articles obtained were systematically compiled and reviewed. 

Table 1 provides information on the various types of applications of Cuscuta reflexa in traditional medicine in India and Bangladesh. 

Phytochemistry of C. reflexa

The active constituents are mannitol, dulcitol, carotenoids, sitosterol, flavonoids,^18,19 isorhamnetin-3-Oneohesperidoside, apigenin-7-β-rutinoside, lycopene,²⁰ 6,7-dimethoxycoumarin (scoparone), 6-hydroxy-4- (4-hydroxyphenyl)-7-methoxycoumarin, quercetin,21 apigenin-7-O-glucoside, kaempferol-3-O-α-rhamnoside, myricetin-3-O-rhamnoside,²² 7-(3’,4’-hydroxyphenyl)- N-[(4-methoxyphenyl)ethyl] propionamide,7-(4- hydoxy,3’-methoxyphenyl)-N-[(4-butylphenyl) ethyl] propenamide,²³ reflexin,²⁴ violaxanthin, lutein, lycopene, carotene, α-cryptoxanthin,²⁵ cerotic, linolenic, amarbelin (pigment), stearic, oleic, and palmitic acids, abscisic acid (leaves), phytosterols (seeds), leuteolin, and its glycosides,²⁶ cuscutin (stem), amino acids, and cuscutalin.²⁷ It also contains benzopyrones, astragallin, quercetin-3-O-glucoside, glucopyranosides, and begenin.^28-30 The esters of higher aliphatic alcohols with saturated fatty acids containing 26 and 28 carbon atoms, respectively, are isolated from the seeds of this plant, amongst them cerotic acid has been identified.²⁵ The literature states that this plant mainly contains caffeic acid depsides and flavonol type flavonoids. Lupeol isolated from C. reflexa is an active triterpenoid with anti-inflammatory, antimicrobial, antitumor, antiprotozoal, and chemoprotective properties.³¹ As an anti-inflammatory agent, lupeol reduces interleukin-4 production by type 2 T-helper cells.^32,33 The structures of the important phytoconstituents are shown in Fig 2.

Ethnomedicinal uses of C. reflexa

This plant has been used extensively in India for its medicinal properties. It finds a mention in the Ayurveda for the treatment of ophthalmic and cardiac problems. It is mostly popular in rural India as it is not costly and is indigenous, safe, and effective. The whole plant in the form of powder and juice is used to treat jaundice while its paste is known to provide relief from rheumatism and gout.³⁴ Its stem is used to treat bilious disorders, constipation, flatulence, and liver complaints. Externally, it is used in the treatment of protracted fever, body pain, and itchy skin. It is also prescribed for treating alopecia.³⁵ The fruits are considered remedies for fever and cough. Its seeds are used as a sedative, anthelmintic, carminnative, diuretic, tonic, diaphoretic, and demulcent.^36,37

In traditional Chinese medicine, the seeds of this plant are used to treat hepatic and renal diseases and also used in correcting Yin and Yang deficiencies. 

Pharmacological uses

Antiarthritic activity

Several studies have demonstrated the efficacy of C. reflexa in treating arthritis. Kumaraswamy et al reported that the ethanolic extract of C. reflexa shows a significant antiarthritic effect.³⁸ Similarly, Vennila et al observed marked antiarthritic activity of C. reflexa in their study.³⁹

Effect on blood pressure

Positive inotropic and cardiotonic activities of the plant’s alcoholic extract were observed when perfused into a frog’s heart by Singh et al. A series of experiments proved that it significantly reduced the blood pressure.⁴⁰ A study reported by Gilani et al described that an alcoholic extract of the stem of this plant causes a dosedependent decrease in arterial blood pressure.⁴¹

Anti-HIV activity

According to Mahmood et al, the aqueous extract of this plant exhibited anti-HIV activity, brought about by the combinatory effects of compounds with different modes of action.⁴²

Antioxidant activity

Yadav et al reported that the ethyl acetate fraction of the ethanolic extract of the stem of C. reflexa showed high antioxidant activity.⁴³

Relaxant and spasmolytic action

A study reported by Prasad et al noted that the aqueous and alcoholic extracts of C. reflexa stem have relaxant and spasmolytic actions on the small intestine of guinea pig and rabbit.⁴⁴

Antibacterial activity

Pal et al observed that the methanol fraction of C. reflexa stem showed significant antibacterial activity against Staphylococcus aureus, Shigella boydii, Pseudomonas aeruginosa, and Escherichia coli with a zone of inhibition ranging from 16 to 24 mm when compared to that of chloramphenicol (10 µg/mL).⁴⁵

Hair growth activity

A study by Pandit S et al demonstrated that the petroleum ether extract of this plant and its isolate were useful in the treatment of androgen-induced alopecia.⁴⁶

Hepatoprotective activity

The methanolic extract of C. reflexa improved the liver function by decreasing the serum alanine transaminase, aspartate transaminase, and alkaline phosphatase levels in hepatotoxic rats.³⁵

Diuretic activity

A study by Sharma S et al reported that the aqueous and alcoholic extracts of the plant showed diuretic activities in Wistar rat.⁴⁷

Hypoglycemic effect

Rahmatullah et al investigated the hypoglycemic effects of chloroform and methanolic extracts of C. reflexa in glucose-loaded Long-Evans rats and noted that both showed significant oral hypoglycemic effects at doses of 50, 100, and 200 mg/kg body weight.⁴⁸

Anticonvulsant activity

The methanolic extract of C. reflexa plant showed marked protection against convulsion induced by chemo-convulsive agents in mice as observed by Gupta et al. ⁴⁹ Similarly, Borole et al reported in their study that the ethanolic extract had anticonvulsant activity.⁵⁰

Anti-inflammatory activity

Suresh et al observed significant anti-inflammatory activities of this plant.⁵¹

Anticancer activity

Chatterjee et al demonstrated significant antitumor activities of the ethanolic and chloroform extracts of C. reflexa. ⁵²

Conclusion

The geographical conditions of India favor the growth of numerous medicinal plants, which are the source of a diverse range of Phytoconstituents with remarkable pharmacological actions. C. reflexa is a promising medicinal plant with excellent therapeutic properties. The medicinal uses of this plant have been illustrated in the classics of India and China. This review article will aid further research in this area