Premna integrifolia L.: A review of its biodiversity, traditional uses and phytochemistry.

Premna integrifolia Linn. (Verbenaceae) is an important woody, medicinal plant and has been prominent place in Ayurveda, Siddha and Unani system of medicines. Objective of the present review is to avail the comprehensive information on ecological biodiversity, traditional uses and phytochemistry of P. integrifolia. Information of the plant was searched using various electronic databases in reference to the terms Premna integrifolia, ecological biodiversity, traditional uses and phytoconstituents of P. integrifolia along with Ayurvedic books, Indian classical texts, pharmacopoeias, journals, etc. There is an inherent difference within the three Ayurvedic Formulary of India (AFIs) published with regard to the botanical sources of Agnimanthā. Complete data of the plant has been collected manually since from the years 1947-2015 and was arranged accordingly. Available data have reports that roots of P. integrifolia are widely used for the preparation of Ayurvedic formulations like Daśamūlakvātha, Ariṣṭa, Cūrṇa and Chayawanprashavleh for the treatment of a variety of afflictions. It has also reported to have p-methoxy cinnamic acid, linalool, linoleic acid, β-sitosterol and flavone luteolin, iridoid glycoside, premnine, ganiarine and ganikarine, premnazole, aphelandrine, pentacyclic terpene betulin, caryophellen, premnenol, premna spirodiene, clerodendrin-A, etc., phytoconstituents in its various parts. There is need to validate its traditional uses, isolation and confirmation of reported phytoconstituents, biological and clinical efficacy by modern analytical and biological techniques which could be recommendation for further scientific research.

INTRODUCTION

Over half a century after launching therapy for treatments, phytochemicals have become an important part of drugs. Actually, 70% of drugs approved between 1940 and 2002 are either natural products or have been developed based on knowledge gained from natural products.[1] India has a rich cultural heritage of traditional medicines which includes Ayurveda, Homeopathy and Siddha system of medicines. Plants are the basic source of medicines in all these systems.[2] A significant number of modern pharmaceutical drugs are thus based on or derived from medicinal plants.[34] Premna integrifolia Linn. (Araṇī or Agnimantha) is an important constituent of ten herb formulation, known as “Daśamūla”, widely used for treating various ailments in Indian system of medicine.[5] There is an inherent difference within the three Ayurvedic Formulary of India (AFIs) published with regard to the botanical sources of Agnimantha.[6] The first edition (Part I) mentions Clerodendrum phlomidis Linn.f. as the authentic botanical source and Premna integrifolia Linn. as well as Premna mucronata Roxb. as substitutes.[7] However, in the second edition of Part I, P. integrifolia has been mentioned as the authentic plant source and C. phlomidis as well as P. mucronata are provided as the substitutes.[8] In Part II of the first edition of AFI on the other hand, C. phlomidis. Linn.f. has been listed as the authentic Agnimantha and Premna obtusifolia R. Br as well as P. mucronata Roxb. are listed as the substitutes.[9] Hence, the basis for this variation in listing of botanical sources for Agnimantha is not provided and hence not clears. Its root extract is an active ingredient of many Ayurvedic preparations like, Ariṣṭam, Avaleham, Kvātham, Ghṛtam and Tailam.[10] P. integrifolia is very important plant during Vedic period where in its stem and sticks were used to produce fire.[11] This review is providing the systematic information on ecological biodiversity, traditional uses and phytochemistry of the P. integrifolia.

Synonyms

Premna serratifolia L.; Premna obtusifolia R. Br.[10121314151617]

Morphology of P. integrifolia

P. integrifolia is a scandent, erect shrub or small tree, more or less thorny on the trunk and large branches. It is large shrub or small tree up to 10 m tall, bole up to 30 cm in diameter, much-branched and sometimes spiny, bark fissured-flaky, brownish-grey and branches are spinous usually. Fruits are drupe, black coloured, obovoid– globose, 3-6 mm long, green turning black, pear shaped, its endocarp being ridged, bony, and 4-celled. Fruits appearing in Aug.–Sept. Flowers having pedicel 0–0.5 mm long, dense corymbs, corolla greenish white with unpleasant smell or disagreeable odour, in terminal pubescent paniculate corymbose cymes, bracts minutes, lanceolate. Calyx 2.5 mm long, thick, glabrous, 2-lipped, one lip 2-toothed, and the other sub entire. Corolla is glabrous outside, tube 3 by 2 mm, cylindrical, hairy inside of the throat, lobes are four in number, oblong, rounded, 1.2 mm long. Stamens slightly exerted filaments hairy at the base. Ovary and style is glabrous, stigma of 2 equal divaricate lobes. Flowering occurs in April–June. Leaves are 5–9 by 3.2–6.3 cm, broadly elliptic, oblong or ovate, obovate to sub-orbicular, obtuse, very shortly acuminate, glabrous, and entire or the upper part dentate, base rounded or sub-acute, main nerves 4–5 pairs, petioles 1–1.6 cm long. Seeds are pear-shaped and oblong. Roots are yellowish brown in colour, woody, branched and somewhat tortuous to cylindrical in shape. Surface gets exfoliated easily and shows prominent longitudinal striations and wrinkles. Roots possess bland taste and slightly aromatic odour. The transverse section of P. integrifolia root shows rhytidoma made up of 15–20 layers of interrupted cork and 2–3 layers of cortex containing small stone cells packed with calcium oxalate prisms. Stone cells are pitted and show thickening on three sides. Inner cork is made up of about 8–10 layers of thin walled tangentially elongated suberised cells. The cortex is made up of collenchymatous parenchyma and shows a single discontinuous layer of elongated lignified, thick walled stone cells (80–125 µ) lodged with 3–5 prisms of calcium oxalate (16–30 µ). Phloem is comparatively wide and parenchymatous. The elements of wood occur in thin radial wedges. Xylem vessels are small (50–138.1 µ) and numerous. Medullary rays are 1–4 seriate, lignified and pitted. Starch (8–30 µ) is found in cortex, phloem and xylem. Powder of root of P. integrifolia is brown in colour having slight aromatic odour and bland taste. Starch is simple, spherical and cup shaped with distinct hilum. Stone cells are small, rectangular to oblong in shape and lodged with prisms, which are found scattered also.[171819202122] The photograph of P. integrifolia with its various parts as shown in [Figure 1a-e].

Figure 1

Photograph of Premna integrifolia (a), young fruits (b), flower buds (c), leaf (d), roots (e) and geo-graphical distribution map (f), ENVIS database

OCCURRENCE AND DISTRIBUTION

It is growing near western sea coast from Bombay to Molucca, Malaysia, Sri Lanka, Andaman and Nicobar. It is also found in forest of South India and West Bengal (Northern part). Moreover, it is also recorded as occurring in the plains of Maharashtra, Gujarat, North Karnataka, Assam, Khasi hills and Tarai. In Orissa, it is found on land periodically covered by tides in Mahanadi delta.[1117212324] Geo-graphical distribution map of P. integrifolia in India as shown in [Figure 1f].

ECOLOGICAL BIODIVERSITY

Ecological biodiversity have been required for better cultivation and farming of P. integrifolia.[17] The details are enlisted as shown in Table 1.

Table 1

Ecological biodiversity of Premna integrifolia

USES

Traditional

Roots are bitter, pungent, heating, laxative, alexipharmic, anaemia, fever, astringent, sweet thermogenic, inflammations, cardiotonic, carminative, digestive, stomachic, tonic, neuralgia, cough, asthma, bronchitis, leprosy, skin disorders, dyspepsia, flatulent, constipation, diabetes, anorexia, liver disorders, general debility and neurological diseases. Roots of the plant are important constituent of ten herb formulation that is, “Daśamūla”, widely used for treating various ailments in Indian system of medicine.[5678910111416171819202325] Leaves are used in the treatment of gonorrhoea, cold, fever and having galactagogue property. The leaves rubbed along with pepper are administered in colds and fevers. Decoction of fresh leaves used for vaginal irrigation.[101826] Decoction of leaves used for bathing infants and in the treatment of beriberi. Extract of leaves for cleaning wounds and for ticks and fleas. Leaves are applied over the bladder facilitate urination. Leaves are good as an external application to piles and tumours and also its decoction is given for flatulence.[27] Stem-bark is used as anti-malarial. The alkali extracted from the ash of the bark is used in ascites.[1028] In the indigenous system of medicine, wood of P. serratifolia is reported to be useful in the treatment of arthritis.[2930] Flowers are used for rheumatism, neuralgia, cold and fever. Whole plant is used in the form of decoction in rheumatism and neuralgia.[1931]

Alternative and complementary medicinal uses

Kochoi is a local patent preparation is claimed to benefit tuberculosis.[28] Polyherbal Ayurvedic preparations containing P. integrifolia are enlisted in Table 2, which includes preparation name, therapeutic use and description.

Table 2

Ayurvedic preparations containing Premna integrifolia

PHYTOCHEMISTRY

Physical

The plant has been reported to have some physical constituents,[21] as shown in Table 3. Alkaloids, carbohydrates, amino acids, steroids, flavonoids, glycosides, tannins and phenolic compounds were found in preliminary phytochemical screening as well as fluorescence analysis of stem-bark and stem wood of P. integrifolia were also performed. These observations would be helpful in the standardization of the drug in crude form and to distinguish the plant from its related adulterants.[212430]

Table 3

Physical constituents present in Premna integrifolia (whole plant)

Chemical

P. integrifolia have been afforded various chemical constituents in various parts, their extractive solvents and category as shown in Table 4 as well as structures of selected isolated compound as shown in Figure 2. The plant also has been reported to have aphelandrine, premnenol, premnaspirodiene, caryophellen.[1416]

Table 4

Summary of chemical constituents present in Premna integrifolia

Figure 2

Structures of selected compounds isolated from Premna integrifolia

CONCLUSION

P. integrifolia have reported to contains p-methoxy cinnamic acid, linalool, linoleic acid, β-sitosterol and flavone luteolin, iridoid glycoside, premnine, ganiarine and ganikarine, premnazole, aphelandrine, pentacyclic terpenebetulin, caryophellen, premnenol, premnaspirodiene, clerodendrin-A, three diterpenoids namely 1β,3α,8β-trihydroxy-pimara-15-ene, 6α,11,12,16-tetrahydroxy-7-oxo-abieta-8,11,13-triene, 2α,19-dihydroxy-pimara-7,15-diene, etc., phytoconstituents in its different parts, which are responsible for its actions. The fluorescence analysis of stem-bark and stem wood of P. integrifolia will be helpful in the standardization of the drug in crude form and to distinguish the plant from its related adulterants. Exploration of chemical constituents is required for establishing mechanisms of action of possible markers and structure-activity-relationship among the constituents present in the root, stem-bark and leaves which will give us the basis for its therapeutic use. P. integrifolia can be used as a good source of active therapeutics. This therapeutically important medicinal plant is not present in the Ayurvedic Pharmacopeia of India and it should be incorporated therein. In Indian market, there are many Ayurvedic preparations containing P. integrifolia that are widely utilized for curing various ailments. Therefore, it is also important to have the study of this plant incorporated into the syllabus of undergraduate and postgraduate pharmacy courses. These studies will be helpful for the development of active molecules and clinical trials a tool for development of Ayurvedic formulations. Depending on the primary information available on, this plant, the isolation and identification of active constituents, modern pharmacological evaluations on isolated compounds and their toxicity testing is to be explored. There is no patent so far on P. integrifolia. Thus, this review provides an easily accessible source of ecological biodiversity, traditional uses and phytochemistry of P. integrifolia.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.