Hyptis suaveolens Poit: A Review on Its Phytochemical and Pharmacological Profile
Praveen S Nayak, Shweta Nayak, Ranjan Shety and P Das
GRY Institute of Pharmacy Borawan, Khargone
Medicinal herbs are the local heritage with global importance. Medicinal herbs have curative properties due to presence of various complex chemical substance of different composition, which are found as secondary plant metabolites in one or more parts of these plants. Hyptis suaveolens (L.) Poit. Is a plat belonging to family Lamiaceae, or the Mint family. It is a family of plants of about 210 genera and some 3,500 species. The original family name is Labiatae, so given because the flowers typically have petals fused into an upper lip and a lower lip. Although this is still considered an acceptable alternate name, most botanists now use the name "Lamiaceae" in referring to this family. They are herbs or undershrubs, distributed over both hemispheres and include a number of medicinal and sub-medicinal plants of great value. This important order has no poisonous members. They mostly exhibit aromatic or bitter-aromatic, stimulant and astringent properties. They are used as tonics, emmenagogues, diaphoretics, antispasmodics, burns and wounds, antimicrobial, antibacterial, antispasmodic, analgesic, anti-inflammatory, headaches, anticatarrhal, anticutaneous. A wide range of chemical compounds including terpenoids, alkaloids, acidic polysaccharide and 33 constituents were identified in the oil of Hyptis suaveolens isolated from its leaves. Extracts and metabolites from this plant have been found to possess pharmacological and insecticidal activities. This contribution provides a comprehensive review of its ethnomedical uses, chemical constituents and the pharmacological profile as a medicinal plant. Particular attention has been given to antioxidant and anti-inflammatory, antibacterial and wound healing properties, insecticidal effects presented in this review such that the potential use of this plant either in pharmaceutics or as an agricultural resource can be evaluated.
KEYWORDS: Hyptis suaveolens (L.) Poit, essential oil, terpenoids, ethnomedical.
The plant, Hyptis suaveolens (L) Poit commonly known as Wilayati tulsi belongs to the family Lamiaceae and is an ethnobotanically important medicinal plant. The plant has been considered as an obnoxious weed, distributed throughout the tropics and subtropics. Almost all parts of this plant are being used in traditional medicine to treat various diseases. The leaves of H. suaveolens have been utilized as a stimulant, carminative, sudorific, galactogogue and as a cure for parasitic cutaneous diseases1. Hyptis suaveolens (L.) Poit. Is a plat belonging to family Lamiaceae, or the Mint family. It is a family of plants of about 210 genera and some 3,500 species. The original family name is Labiatae, so given because the flowers typically have petals fused into an upper lip and a lower lip. Although this is still considered an acceptable alternate name, most botanists now use the name "Lamiaceae" in referring to this family. They are herbs or undershrubs, distributed over both hemispheres and includes a number of medicinal and sub-medicinal plants of great value2.
Hyptis is an annual or perennial upright branched plant with a characteristic aromatic minty smell, generally growing 1 to 1.5 metres high, but at times reach 2 metres. Under favourable conditions it can act as a perennial plant.
are square with opposite leaves which are broader at the base than at the tip,
varying from 2.5 to 7 cm long and 1 to 5 cm wide, with serrated margins. Small
lavender blue flowers occur in clusters in the leaf axils. Seeds are dark brown
to black in colour, shield shaped, 3.5 to 4 mm long
and 2.5 to 3 mm wide3.
The Mundas (group of tribal from Orissa and West
Bengal- India) use the plant for headache; the powder of leaf is used as snuff
to stop bleeding of the nose. The Lodhas (a tribal
"Strong-scented herb to 3 m tall with quadrate hairy, erect, branched stems. When crushed, the plant gives off a characteristic minty smell. The broad leaves are in opposite pairs up the stem, with small mauve flowers in clusters in the upper leaf axils. Leaves, ovate, acute, 3-5 cm long and 2-4 cm wide, the margins serrulate, lower surface densely hairy; petioles up to 3 cm long. Inflorescence, axillary, 3-to 4-flowered clusters, flowers in small cymes, along branch end with reduced leaves. Calyx 5 mm long, in flower, 10 mm long in fruit, corolla 2-lipped, purplish blue Fruits ribbed enclosed by the calyx. Nutlets about 1.2-1.5 mm long slightly notched at the end." The persistent spiny calyx enclosing the seeds assists with their dispersal by adhering to clothing, fur and wool. The plant gives flowers and fruits in autumn and winter seasons.
Throughout drier parts
Found in plantation crop areas, waste places and pastures, along river banks, roadsides, waste areas & clearings.
Hyptis suaveolens poit (Laminaceae), known as Ganga tuilsi, is an aromatic strongly scented herb found in Deccan peninsula, north east India, Andaman and nicobar island, Philippines and tropical America. In the traditional system of medicine , the plant is used as a stimulant, carminative, for wounds, sudorific, galactogogue, catarrhal condition, infection of uterus, parasitic skin diseases5.
leaves of Hyptis suaveolens are used as an
anticancer6. It is
considered to be stimulant, carminative, sudorific
and lactagogue and is used in ethnomedicine
as an anticatarrhal, anticutaneous,
parasitic, and as an antipyretic7. In the tropical
Hyptis suaveolens is known as Ganga Tulsi in Chhattisgarh. This aromatic herb holds a reputed position among the traditional healers of this region, having expertise in treatment of different types of cancer. They use its different parts both internally as well as externally in treatment. The use of leaves externally for treatment of cancerous wound is very popular among the healers13.
The chemical composition of essential oils of
the leaves of Hyptis suaveolens
collected from two different sources in
Tchoumbougnang et al evaluated essential oil of four different species of Hyptis and reported sabinene (20.6%), b-caryophyllene (17.5%) and bergamotol (10.9%) as the main constituent of H. suaveolens15.
Chemical composition of essential oils from this plant was carried out in a different study performed by Oliveira and coworkers to investigate chemical composition of the essential oils of seven populations of Hyptis suaveolens in vegetative, flowering and fruiting stages and also their interpopulation variability. They found sabinene, limonene, 1,8-cineole, (E)-caryophyllene and spathulenol as the principal constituents and when results from the chemical analysis were submitted to Principal Component and Chemometric Cluster Analysis, it showed that five groups of populations could be distinguished with respect to the stage of growth and, high content of bicyclogermacrene/ terpin-4-ol, sabinene, 1,8-cineole/spathulenol, limonene/gamma-terpinene and spathulenol/(E)-caryophyllene. Pattern of geographic-variation in essential oil composition indicated that triterpenes hydrocarbons were mainly produced in plants from sampling sites located in higher latitudes and altitudes regardless of the phase of growth, while sesquiterpenes were mainly produced in fruiting samples grown at lower ones. The Canonical Correlation Analysis between the soil sampling sites with the populations revealed a significant relationship between oil components and edaphic factors. Sesquiterpenes and potential acidity, A1, and A1 saturation load was fairly strong onto the first canonical variate and were related to fruiting samples collected at lower latitudes. On the other hand, triterpenes hydrocarbons were strongly related to chemical balance in soils (P, Zn, Cu, Mn, base saturation, neutral pH), which was related to the vegetative/flowering sampling at higher latitudes, thus this study could give an insight into variation found in constituents of essential oils extracted from different location and at different stages of plant development16.
Ranaa et al analyzed the
chemical constituents of the volatile oil of mature flowering twigs of wild H.swaveolens growing widely in northern
Silva et al in an earlier study had analyzed the oils, obtained from leaves, stems and inflorescences, which demonstrated that the inflorescence produced more oil than the leaves and stems. A total of 38 compounds were identified, 16 monoterpenes (42.1%), 13 sesquiterpenes (36.8%), alkanes 7 (15.8%), benzotiazole and aromatic ketone both 1(2.6%) each. The sesquiterpenes b-caryophyllene (10.39%) and spathulenol (13,30%) were present in higher yields in the leaves and steams, respectively. The triterpenes 1, 8-cineole (27.47%) was the major compound present in the inflorescences essential oil18.
The essential oil obtained after hydrodistillation of the leaves of H. suaveolens gave an average yield of 0.1 %. The main constituents were 1, 8-cineole (32%) and b- caryophyllene (29%) while other components detected were a-thujene, a-pinene, camphene, sabinene, b-pinene, myrcene, a-phellandrene, g-terpinene, a-terpinolene, cimenenol, linalool, fenchol, camphor, 4-borneol, 4-terpinenol, a-terpineol, eugenol, a-copaene, b-elemene, a-humulene, a-bergamotene, aromadendrene, g-cadinene and d-cadinene 19. Thoppil and Jose had performed a study of chemical composition of essential oil in two ethnomedicinal species of Hyptis and concluded that citronellyl acetate, b-caryophyllene, piperitone oxide and geranyl acetate were common in both taxa, which revealed their phylogenetic relationship20.
From the hexane, chloroform and methanol extracts of the whole plant of Hyptis suaveolens for chemical constituents, which resulted in isolation of three diterpenes: suaveolic acid, suaveolol and methyl suaveolate , two steroids: β-sitosterol and β-sitosteryl glucoside , two triterpenes: oleanolic acid and ursolic acid together with two phenolics: rosmarinic acid and methyl rosmarinate21 .
Bioactivity-guided fractionation of the petroleum ether extract of the leaves of Hyptis suaveolens, widely used in Traditional Medicine, has led to the isolation of an abietane-type diterpenoid endoperoxide, 13α-epi-dioxiabiet-8(14)-en-18-ol, displaying high antiplasmodial activity (IC50 0.1 μg/ml)22.
The acidic polysaccharide from the seed-coat mucilage of Hyptis suaveolens is a highly branched -fuco-4-O-methyl--glucurono--xylan for which a structure is proposed having a 4-linked β--xylan backbone carrying side chains of single 4-O-methyl-α--glucuronic acid residues at O-2 and 2-O--fucopyranosyl--xylopyranose units at O-3 23.
From the aerial parts of Hyptis suaveolens, a novel triterpenoid, hyptadienic acid, and elucidated its structure as A (1)-1,19a-dihydroxy-urs-2(3),12-dien-28-oic acid24.
Gowda studied the polysaccharide components of the seed coat mucilage from H.suaveolens and revealed that the mucilage isolated from the seed coat contained L-fucose, D-xylose, D-mannose, D-galactose, D-glucose and 4-O-methyl-D-glucuronic acid in the mol ratios 1.0:2.5:1.5:7.0:12.5:1.1 25.
A natural triterpenoid, 3β-hydroxylup-12-en-28-oic acid, has been isolated from the roots of Hyptis suaveolens in addition to α- and β-amyrin26.
Wound healing activity:
Ethanolic extract of leaves of Hyptis suaveolens was evaluated for its wound healing activity in ether-anaesthetized Wistar rats at two different doses (400 and 800 mg/kg) using incision, excision, and dead space wound model. Significant increase in skin breaking strength, granuloma breaking strength, wound contraction, hydroxyproline content and dry granuloma weight and decrease in epithelization period was observed. A supportive study made on granuloma tissue to estimate the levels of catalase and superoxide dismutase recorded a significant increase in the level of these antioxidant enzymes. Granuloma tissue was subjected to histopathological examination to determine the pattern of lay-down for collagen using Van Gieson and Masson Trichrome stains. Enhanced wound healing activity may be due to free radical scavenging action of the plant and enhanced level of antioxidant enzymes in granuloma tissue. Better collagenation may be because of improved antioxidant studies29.
Hyptis suaveolens can be a promising insecticide against a number of insect species that infest our crops and food grains30. Similarly the insecticidal activities of petroleum ether extract of H. suaveolens seeds on second instar larvae of the Diamond back moth, Plutella xylostella, where the seed extract showed high toxicity against P. xylostella with LC 50values of 6.49 and 4.39 % were recorded after 24 h and 48 h exposure, respectively, while at 24 and 48 h of exposure, mortality was significantly (p=0.05) higher (63 and 82%) at 10% concentration than at other concentrations31.
Antioxidant and Cytotoxic properties:
The antioxidant and cytotoxic properties of H.suaveolens crude extracts and also insecticidal activities of crude extract on oriental fruit flies. The ethanolic seed extract showed higher amount of total phenolic compounds with antioxidant and cytotoxic activities in comparison to the leaf extract. Similarly, the ethanolic seed extract was able to control all eggs, larvae and adult oriental fruit flies. Ethanol extract was found to be more effective than water extract. Their study also showed that there was no correlation between antioxidant property and toxicity of the extract32.
The 6-month chronic toxicity in Wistar rats. Changes in the body weights, actual and relative organ weights were not significantly demonstrated throughout the study. The results of hematological, biochemical parameters and histopathological lesions showed that the extract did not produce any significant dose related changes and extract of H. suaveolens at the given doses did not produce any significant toxic effect in rats during 6-month period of the treatment 33.
Antifeedant ovicidal and larvicidal activity:
Different extracts of the leaves of H. suaveolens were tested for antifeedant, oviposition deterrent, ovicidal and larvicidal activity against lepidopteran pests, Helicoverpa armigera and Spodoptera litura. Maximum antifeedant and ovicidal activity were recorded in ethyl acetate extract and the bioactive fractions were identified as 5-keto-pent- 3, 4-enyl-2’-phenol and 5-pentylmethylene oxy-4, 4-dimethyl–Cyclohexenol, respectively34.
Hepatotoxic and nephrotoxic activity:
The plant hyptis suaveolens is hepatotoxic and nephrotoxic in rats. The toxic effects of the plant Hyptis suaveolens on serum biochemical parameters and histopathology was studied in albino rats using crude aqueous extracts of the leaves of the plant for 28 days. They analyzed serum biochemical parameters of the rats and found that blood urea nitrogen of the rats administered with H.suaveolens were increased significantly (P < 0.05), while the histopathology of the rats showed liver with peri-hepatic accumulation of proteineous material, kidneys with diffused area of nephrosis of tubular epithelial cells35.
The dried alcoholic (90%) extract of the aerial parts of H.suaveolens possesses immunomodulation as well as anti-oxidant property, and the latter property may be responsible for the amelioration of the immunosuppressant effect of pyrogallol that produces immunosuppression and oxidative stress36.
Ethanolic extracts from leaves of H. suaveolens demonstrated mild to moderate antifungal activity against dermatophytes 37.
The dehydroabietinol isolated from Hyptis suaveolens was found to inhibit growth of chloroquine-sensitive as well as chloroquine-resistant strains of Plasmodium falciparum cultivated in erythrocytes in vitro (IC50 26-27 µM)38.
Essential oil from the leaves of Hyptis suaveolens showed absolute volatile toxicity against Pythium aphanidermatum and P. debaryanum. The oil was tested individually as well as in combination with oil extracted from other plants, which showed that the fungitoxic activity of the mixtures of oils found to be several times enhanced than that of the individual oil42.
The petroleum ether, alcoholic and aqueous extract of H. suaveolens (leaves) was tested for antifertility activity in female albino rats for anti-zygotic, blastocystotoxic, anti-implantation, or early abortifacient activity. The alcoholic extract showed 100% antifertility effect at a dose of 125 mg/kg43.
The essential oils of Hyptis suaveolens (Labiatae) and Alpinia galanga (Zingiberaceae) obtained by hydrodistillation were compared for their antioxidant potentials and antimicrobial activities on the basis of chemical components of both oils. The antioxidant activity of the essential oils was determined by using two complementary methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical decolorization assay. A good correlation of % inhibition was observed between these two methods. The results obtained indicated that the essential oil of A. galanga possessed stronger antioxidant activity than that of H. suaveolens with the IC50 values of 550 and 3721 μg/ml, respectively. The antimicrobial activity of the essential oils was compared by the dilution method. The results showed that the essential oil of A. galanga was more active against the test microorganisms with the MID values of 1:320, 1:320, 1:160, 1:80, 1:80, 1:160 and 1:160 against Staphylococcus aureus, Streptococcus suis, Erysipelothrix rhusiopathiac, Pseudomonas aeruginosa, Escherichia coli, Pasteurella multocida and Actinomyces pyogenes, respectively44.
Comparison of antiinflammatory activity of diclofenac sodium with leaf essential oil of Hyptis suaveloens poit was done. Study reveals that the leaf essential oil has better anti-inflammatory activity than the marketed formulation45.
Human lymphocyte activity:
The effect of Hyptis suaveolens on lymphocyte proliferation. The extracts of this plant have stimulating activity on human lymphocytes and could be clinically useful for modulating immune functions of the body46.
Wound Healing Activity and antimicrobial activity:
The leaves of Hyptis Suaveolens were exhaustively extracted by soxhlet apparatus with different solvents like petroleum ether, solvent ether, chloroform, alcohol and chloroform water in ascending order of the polarity. All the five extracts were subjected to antibacterial screening by using the cup plate method. The petroleum ether, alcoholic and chloroform water extract showed maximum zone of inhibition. So these extracts were taken for wound healing activity. The effect of petroleum ether, alcohol, and aqueous extract of leaves was evaluated in excision, incision and dead space wound healing models using Albino Wistar rats. Among the extracts, petroleum ether extracts showed significant wound healing activity on all three wound models compared to other extracts by calculating the parameters, percentage closure of excision wound, period of epithelization, tensile strength, dry weight granulation tissue, breaking strength of granulation tissue and hydroxyproline content. Histopathological study of the granulation tissue of the petroleum ether extract treated group evidenced increased collagenation when compared to control group of animals47.
Insect repellent properties:
In laboratory tests, ethyl acetate extracts of Hyptis suaveolens Poit significantly reduced probing activity of Aedes aegypti (L.). Volatile compounds from H. suaveolens were collected by solid phase microextraction (SPME). Alternatively, compounds in the plant were subjected to extraction by organic solvents of different polarities or by steam distillation and collection by SPME. Compounds collected were identified by gas chromatography-mass spectrometry. The selected plant species contained numerous volatiles known to have insecticidal, acaricidal, pesticidal, and insect repellent properties48.
Herbal drug which are used in various traditional medicine, needs detailed investigation with ethno-pharmacological approach. In the present review we have made to explorer the all details of the Hyptis suaveolens information its botany, habitat, traditional and modern uses, it is commonly found as weed on way side and at waste places throughout India. Further studies going on the plant to elaborate the more activity in plant constitutes, therefore there are many plant uses are mentioned in ayurveda on that base go for further studies.
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