INTRODUCTION

Holy basil is a perennial or annual in the mint family that exhibits the square stem and volatile oils characteristic of its family.¹ It is erect, very branched, strongly aromatic, and mildly hairy.² Holy basil is native to India and parts of northern and eastern Africa, Hainan Island, and Taiwan, and grows wild throughout India and up to an altitude of 5,900 feet (1,800 meters) in the Himalayas.^3-5 In China, it occurs in dry, sandy areas of Hainan and Sichuan, as well as in Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Thailand, and Vietnam.⁶ Holy basil is cultivated in Southeast Asia and also grows abundantly in Australia, West Africa, and some Arab countries.^1,3 In India, the dried leaf, dried seed, and dried whole plant are used separately in the traditional medicine systems of Ayurveda, Siddha, and Unani, as well as in Indian folk medicine. The materials of commerce are obtained mainly from cultivated sources throughout India.⁷

HISTORY AND CULTURAL SIGNIFICANCE

The genus name, Ocimum, means “fragrant lipped,” and the species name, tenuiflorum, means “slender” or “small flowers.” In India, O. tenuiflorum is known by a variety of names, including: tulasi, ajaka, ramatulasi, and vriddhatulasi in Sanskrit; tulsi, baranda, kalatulsi, and vranda in Hindi; tulsi, tulshi, kalatulsi, and kural in Bengali; tulsi, tulasi, and talasi in Gujarati; tulasi, kalatulasi, karitulasi, sritulasi, and vishnutulasi in Kannada; tulsi in Konkani; tulasi, krishnatulasi, and trittavu in Malayam; tulasa and tulasichajadha in Marathi; tulsi and bantulsi in Punjabi; tulasi in Tamil; and tulasi and krishnatulasi in Telegu.^2,4,8 In some circles, the previous Latin binomial, O. sanctum, is still preferred, as sanctum refers to the historical “holy” status of the plant. Sorting out the species that are referred to as holy basil can be confusing. Ocimum tenuiflorum has at least two varieties: Krishna or Shyama Tulsi (dark green-to-purple-leaved) and Sri or Rama Tulsi (green-leaved).^4,9 A third variety, Kapoor (or Kapur) Tulsi (also green-leaved), may or may not be O. tenuiflorum; some sources surmise that it is O. kilimandscharicum, native to East Africa.^10,11 A separate species, O. gratissimum (“very grateful basil” or “pleasing basil”), is known as Forest or Vana Tulsi. Even though it is a different species, O. gratissimum also is considered sacred in India and is used in the same ways as the O. tenuiflorum varieties.²

Tulsi is one of the principal herbs used in the Ayurvedic medicine system, in which it is known alternately as “The Queen of Herbs,” “The Incomparable One,” and “The Mother Medicine of Nature.”⁹ It holds a supreme place in the ancient Vedic scriptures and is integrated into daily life by Hindus through religious worship. Hindu homes typically have a tulsi plant growing in an earthen pot in or around the home. In Ayurveda, it is believed that the best way to take tulsi medicinally is in its raw, fresh, whole form as a hot-water infusion.⁹

Tulsi is combined with various other herbs in Ayurvedic preparations to treat the following conditions and symptoms: abscesses, abdominal pain, teething-related ailments, anemia, arthritis, boils, bronchial asthma, bronchitis, catarrh (respiratory tract inflammation), constipation, coryza (cold), cough, diarrhea due to giardiasis or amebiasis (both caused by microscopic parasites), dysentery, eye diseases (topically), headaches, fever (including chronic and malarial fevers), filariasis (a parasitic disease caused by nematodes), general debility or weakness, goiter, gonorrhea, hernias, intestinal worms, jaundice, leucoderma (loss of skin pigmentation; applied topically), loose teeth (as a snuff or mouth lotion), loss of appetite, lumbago (low back pain), memory enhancement, piles (inflamed hemorrhoids), premature aging and graying of hair, pulmonary tuberculosis, rheumatism, ringworm (topically), syphilis, thinness of semen, strangury (painful, frequent urination in small volume), tubercular lymph nodes, tubercular leprosy, and tumors.^2,9,12

Ayurvedic medicine also has credited holy basil with numerous actions, including the following: adaptogenic, antibacterial, antiperiodic (prevents the recurrence of disease symptoms), antipyretic/febrifuge (reduces fever), antiseptic, antispasmodic, carminative (relieves intestinal gas), diaphoretic (promotes sweating), expectorant, nervine, and stimulant.^2,9,12,13

There are O. tenuiflorum standards monographs published in the Ayurvedic Pharmacopoeia of India (Vol. II, 1999, and Vol. IV, 2004) and Unani Pharmacopoeia of India (Vol. V, 2008), as well as Thai Herbal Pharmacopoeia (Vol. I, 1995), Vietnamese Pharmacopoeia (1^st ed., 1983), and World Health Organization (WHO) Monographs (Vol. 2, 2002).² The WHO monograph lists other uses that are described in pharmacopeias and in traditional systems of medicine including treatment of arthritis, asthma, bronchitis, common cold, diabetes, fever, influenza, peptic ulcer, and rheumatism.³

CURRENT AUTHORIZED USES IN COSMETICS, FOODS, AND MEDICINES

In countries where the Ayurvedic system of medicine is recognized and practiced (e.g., India, Bangladesh, Bhutan, Malaysia, Nepal, and Sri Lanka), the powdered, dried leaf of holy basil is used therapeutically, depending on the formulation, for treating the following conditions: acute rhinitis (inflammation of the mucous membrane of the nose), asthma or dyspnea (shortness of breath), hiccups, cough, tastelessness (inability to differentiate tastes, which may be due to improper digestion or lack of desire for food), worm infestation, skin diseases, intercostal neuralgia (pain in the tissue between the ribs), and pleurodynia (pain in the upper chest [pleural cavity]). Similarly, the dried whole plant (prepared in juice form) is used to treat asthma or dyspnea, hiccups, cough, worm infestation, and skin diseases, as well as pleurisy, calculi (stones), vomiting, and eye diseases.¹⁴

The powdered seed also is used, depending on the formulation in which it occurs, for treatment of acute rhinitis, asthma or dyspnea, hiccups, cough, skin diseases, tastelessness, intercostal neuralgia and pleurodynina, as well as inflammation, intestinal helminths (worm-like parasites), dysuria or painful urination, foul smell, artificial poisons, hematological diseases, and parasitic infections.¹⁵

In countries where the Unani system of medicine is recognized and practiced (e.g., Bangladesh, India, Malaysia, Pakistan, and Sri Lanka), holy basil (rehan) leaf and whole plant are used therapeutically (in dried or juice forms) to treat amenorrhea, cough, palpitation, and weakness of the stomach.¹⁶

In Canada, holy basil leaf and seed are classified as active ingredients of licensed natural health products (NHPs) that require pre-marketing authorization from the Natural Health Products Directorate (NHPD) and must be manufactured in compliance with NHP good manufacturing practices (GMPs). Authorized uses for holy basil leaf preparations (powdered leaf, decoctions, infusions, and non-standardized aqueous extracts) outlined in the NHPD compendial monograph include “traditionally used in Ayurveda (as an expectorant and/or demulcent) to help relieve cough (Kasa) and colds,” “traditionally used in Ayurveda (as an expectorant) to help relieve respiratory catarrh,” “traditionally used in Ayurveda as a cardiotonic (Hrdya),” and “traditionally used in Ayurveda to aid digestion (Dipani) and stimulate appetite (stomachic).”¹⁷

The powdered dried seed may be labeled and marketed in Canada for the following uses: “traditionally used in Ayurveda (as a demulcent) to help relieve cough (Kasa),” “traditionally used in Ayurveda as a cardiotonic (Hrdya),” and “traditionally used in Ayurveda to aid digestion (Dipani).”¹⁸

In the United States, holy basil is not listed as Generally Recognized as Safe (GRAS) in the Code of Federal Regulations (CFR) for use in conventional food products, nor does holy basil appear in the US Food and Drug Administration’s (FDA) GRAS Notice Inventory database. Holy basil plant parts are permitted, however, as dietary supplement components that require FDA notification within 30 days of marketing a product (if a “structure-function” claim is made), and the product must be manufactured according to dietary supplement GMPs. In 2012, the United States Pharmacopeial Convention (USP) published proposed dietary supplement quality standards monographs for “Holy Basil” (dried leaf) and “Powdered Holy Basil” (pulverized dried leaf) containing no less than 0.5% triterpenes, calculated as the sum of oleanolic acid and ursolic acid, and a corresponding “Powdered Holy Basil Extract” monograph for public consultation and finalization in 2013. The new USP monographs will be acceptable for use as holy basil leaf dietary supplement component specifications.¹⁹

Concerning use of holy basil in cosmetic products, the European Commission Health and Consumers Directorate lists “Ocimum Tenuiflorum Extract” for skin-conditioning functions, and “Ocimum Tenuiflorum Oil” (wax obtained from the leaves of O. tenuiflorum) for emollient (softens and smooths the skin), hair-conditioning, and skin-conditioning functions.²⁰

MODERN RESEARCH

Holy basil contains alkaloids, carbohydrates, fats, glycosides, phenols, proteins, saponins, tannins, and terpenes.⁹ Pharmacological and in vitro laboratory studies have exhibited adaptogenic, anabolic, anti-asthmatic, anti-diabetic, antidiarrheal, anti-inflammatory, antioxidant, antipyretic, anti-radiation, anti-stress, calming, cardiac depressant, contraceptive, hepatoprotective, hypotensive, immunomodulatory, neuro- and cardio-protective, and mosquito-repelling properties for the plant.^9,13

Tulsi is believed to increase immunity when taken on an empty stomach. In a 2011 double-blind, randomized, controlled trial, 24 healthy volunteers consumed 300 mg capsules of holy basil leaves (70% ethanolic extract; Dabur Pharmaceutical Ltd., Ghaziabad, India) or placebo on empty stomachs every day for four weeks, followed by a three-week washout period before crossover to the next intervention. The holy basil group had significantly increased levels of IFN-γ, IL-4, and percentages of T-helper cells and natural killer (NK) cells, showing holy basil’s immunomodulatory effects in humans.²¹

Two double-blind pilot studies in 2009 investigated holy basil and four other Ayurvedic herbs for their reputed immune-enhancing effect.²² The first study included 32 volunteers randomized to two treatment groups of 16 each who consumed three cups daily (over the course of two months) of regular tea or Natural Care tea (Hindustan Unilever Research Center, Bangalore, India), which contains holy basil (0.5%); ashwagandha (Withania somnifera, Solanaceae, 0.5%); licorice (Glycyrrhiza glabra, Fabaceae, 0.5%); ginger (Zingiber officinale, Zingiberaceae, 1.5%); and cardamom (Elettaria cardmomum, Zingiberaceae, 1.5%). NK cell activity was measured after one and two months of tea consumption. While there were no significant changes in either group at the end of the first month, NK cell activity significantly increased after two months in the Natural Care tea drinkers but not in the regular tea group.

The second study was a larger, double-blind, crossover study in which 110 subjects (60 male, 40 female [sic]) were assigned randomly to two groups.²² Each group consumed three cups of tea (Natural Care or regular [Camellia sinensis, Theaceae]) per day for two months. NK cell activity was measured before a 15-day washout period when no tea was drunk. The groups then switched to the other tea for another two months, after which NK cell activity was measured again. NK cell activity increased in both groups after two months, but the increase in the Natural Care tea drinking groups was approximately 4.2 times higher, while the NK cell activity in the regular tea group was about 2.9 times higher.

Holy basil was investigated for its effect on generalized anxiety disorder (GAD) in a 2008 study.²³ The study was conducted on 35 patients suffering from GAD from the outpatient clinics of the J. B. Roy State Ayurvedic Medical College and Hospital in Calcutta, India. Each subject was given 500 mg holy basil (70% ethanol extraction repeated three times, reduced in a rotary evaporator, then freeze-dried and packaged in gelatin capsules; manufacturer not stated) orally twice daily after a meal for 60 days. Baseline score index was 84.42±7.56 at the start, decreased to 68.17±7.84 (-19.2%) at 30 days, and 55.54±7.20 (-34.2%) at 60 days. Stress index at baseline was 95.65±8.42 and decreased to 84.32±9.08 (-11.5%) at 30 days and 68.45±9.60 (-27.5%) at 60 days. Additionally, depression index declined from 66.45±5.68 at baseline to 57.65±5.04 (-13.2%) at 30 days and 45.97±6.27 (30.8%) at 60 days.

A 2001 open, prospective, multicenter clinical study investigated the efficacy of an herbal eye drop containing holy basil on various ophthalmic conditions.²⁴ Ophthacare^® is an aqueous extract of six plants and honey made by Himalaya Drug Co. (Makali, Bangalore, India). Ophthacare comprises 0.60% w/v ajowan seed (Trachyspermum ammi, syn. Carum copticum, Apiaceae); 0.65% w/v belleric myrobalan fruit (Terminalia bellerica, Combretaceae); 1.30% w/v amla (Phyllanthus emblica, syn. Emblica officinalis, Euphorbiaceae); 1.30% w/v turmeric rhizome (Curcuma longa, Zingiberaceae); 1.30% w/v holy basil leaf; 1.10% w/v damask rose petals (Rosa damascena, Rosaceae); 0.5% w/v camphor crystal (Cinnamomum camphora, Lauraceae); and 3.70% w/v honey. Eye drops were applied at the rate of two drops four times daily for 15 days on 100 patients with acute conjunctivitis (allergic, bacterial, or viral) (n=35), acute dacryocystitis (inflammation of the nasolacrimal sac) (n=20), conjunctival xerosis (dry eye) (n=7), degenerative conditions such as pterygium/pinguecula (n=15), or who were postoperative cataract patients (n=23). Therapeutic responses occurred in most of the patients with the postoperative cataract patients experiencing the most benefit (95%), followed by dacryocystitis patients (88.2%), acute conjunctivitis patients (87.5%), patients with degenerative conditions (76.9%), and conjunctival xerosis patients (66.7%).

In a 1996 randomized, single-blind, placebo-controlled, crossover study, 40 type 2 diabetes patients were randomized to consume holy basil leaf tea for four weeks followed by placebo leaf tea for four weeks or the reverse after a five-day run-in period in which they all consumed holy basil leaf tea.²⁵ The authors concluded that consumption of the holy basil tea resulted in significant reduction in fasting blood sugar and postprandial blood sugar, as well as a moderate reduction in cholesterol. However, the Jadad score for this study was 1 (on a scale of 0 [very poor] to 5 [rigorous]), suggesting lack of adequate design and controls and that further studies are necessary.

A number of clinical studies were reported in the late 1900s, including ones for treatment of bronchial asthma, viral encephalitis, stress-related arterial hypertension, cell-mediated and humoral immune response, and chronic fatigue.⁹ While these studies suggested some positive benefit for the conditions studied, they were all small pilot studies.

FUTURE OUTLOOK

Of the estimated 960 medicinal plant species that form the source of 1,289 botanical raw drugs traded in India, O. tenuiflorum is among the top 117 species whose annual domestic consumption exceeds 100 metric tons (MT). Ranking sixth in terms of volume, Indian domestic consumption of holy basil is estimated at 3,533 MT. In terms of trade volume and consumption, annual demand was estimated to be between 2,000 to 5,000 MT in 2008. Most of the commercial supply is produced through cultivation.²⁶

Demand for holy basil with sustainability certifications (e.g., organically grown, biodynamic, and/or fair trade) appears to be increasing, evidenced by the fact that Indian farms are beginning to implement both ecological and social standards for the growing export market, and US companies are investing in the marketing of ecological and socially responsible certified tulsi products. Two such examples are the Phalada Agro Research Foundation Pvt. Ltd. (Bangalore, India) and the Putharjhora Tea Garden Pvt. Ltd. (Calcutta, West Bengal, India).

On the American side of the trade, Honest Tea (Bethesda, MD) has worked closely with Fair Trade USA (Oakland, CA) to help the Organic Tulsi Farm, part of the Phalada cooperative of 750 farms, obtain Fair Trade certification.²⁷ Phalada’s tulsi producer group and processing unit also hold Fair For Life Social and FairTrade Certification issued by the Institute for Market Ecology (IMO), as well as biodynamic certification from Demeter International.^28,29

Another US company, Davidson’s Organics (Sparks, NV), now markets certified fair trade, biodynamic, and organic tulsi leaf teas grown by certified operator Putharjhora Tea Garden Pvt. Ltd.³⁰

Other big players in the marketing of sustainable tulsi teas in North America include Choice Organic Teas (Seattle, WA), which specializes in fair trade, organic, and Non-GMO-Project Verified teas; Pukka Herbs Ltd. (Bristol, UK), which specializes in fair trade, FairWild^®, and organic teas; and Organic India^® (Boulder, CO). Organic India has decided not to pursue fair trade certification at this time, but states that its labor and trade practices go above and beyond what any certification requires, i.e., they provide their tulsi farmers and their families with health care, education, and a sustainable method of agriculture.³¹

Presently, in the Canadian market, there are 50 licensed NHPs that contain holy basil leaf, leaf extract, or seed as active ingredients, including, for example, Holy Basil 500 mg Vegetarian Capsules (Organika Health Products Inc.), Holy Basil Tea (St. Francis Herb Farm, Inc.), Perfect Calm^® tablets, Wholemega^® Focus capsules, and Zyflamend^® P.M. capsules (New Chapter Inc.).³²

—Gayle Engels and Josef Brinckmann

References

1. Mondal S, Mirdha BR, Mahapatra SC. The science behind sacredness of tulsi (Ocimum sanctum Linn.). Indian J Physiol Pharmacol. 2009;58(4):291-306.
2. Parotta JA. Healing Plants of Peninsular India. New York: CABI Publishing; 2001.
3. World Health Organization. Folium Ocimi Sancti. In: WHO Monographs on Selected Medicinal Plants, Volume 2. Geneva, Switzerland: World Health Organization; 2002:206-216.
4. Anonymous. Wealth of India 1991. Publication and Information Directorate; New Delhi, India: CSIR; 1991:79-89.
5. Gupta AK, Tandon N, Sharma M (eds.). Ocimum sanctum Linn. In: Quality Standards of Indian Medicinal Plants, Volume 5. New Delhi, India: Medicinal Plants Unit, Indian Council of Medical Research; 2008:275-284.
6. Li XY, Hedge IC. Lamiaceae. In: Wu ZY, Raven PH (eds.). Flora of China, Vol. 17 (Verbenaceae through Solanaceae). Beijing: Science Press, and St. Louis: Missouri Botanical Garden Press; 1994:296-297.
7. Ved DK, Goraya GS. Demand and Supply of Medicinal Plants in India. Dehra Dun, India: Bishen Singh Mahendra Pal Singh. 2008.
8. McGuffin M, Kartesz JT, Leung AY, Tucker AO. American Herbal Products Association’s Herbs of Commerce, 2nd ed. Silver Springs, MD: American Herbal Products Association; 2000.
9. Singh N, Hoette Y. Tulsi: The Mother Medicine of Nature. Lucknow, India: International Institute of Herbal Medicine; 2002.
10. Kashyap CP, Ranjeet K, Vikrant A, Vipin K. Therapeutic potency of Ocimum kilimandscharicum Guerke – a review. Global Journal of Pharmacology. 2011;5(3):191-200.
11. Dolly G, Nidhi S, Bps S, Shweta R, Shikha A. Ocimum kilimandscharicum: a systematic review. Journal of Drug Delivery and Therapeutics. 2012;2(3):45-52.
12. Tirtha SSS. The Ayurveda Encyclopedia: Natural Secrets to Healing, Prevention, and Longevity. Bayville, NY: Ayurveda Holistic Center Press; 1998.
13. Khare CP. Indian Herbal Therapies Based on Latest Scientific Research. New Delhi: Vishv Vijay Private Limited; 2000.
14. Ayurvedic Pharmacopoeia Committee. The Ayurvedic Pharmacopoeia of India, Part I, Volume II. New Delhi, India: Government of India, Ministry of Health and Family Welfare, Department of Ayurveda, Yoga & Naturopathy, Unani, Siddha and Homoeopathy (AYUSH). 1999.
15. Ayurvedic Pharmacopoeia Committee. The Ayurvedic Pharmacopoeia of India, Part I, Volume IV. New Delhi, India: Government of India, Ministry of Health and Family Welfare, Department of Ayurveda, Yoga & Naturopathy, Unani, Siddha and Homoeopathy (AYUSH). 2004.
16. Unani Pharmacopoeia Committee. The Unani Pharmacopoeia of India, Part I, Volume V, New Delhi, India: Government of India, Ministry of Health and Family Welfare, Department of Ayurveda, Yoga & Naturopathy, Unani, Siddha and Homoeopathy (AYUSH). 2008.
17. Monograph: Holy Basil - Ocimum tenuiflorum - Leaf (Under Consultation). Natural Health Products Directorate (NHPD). Ottawa, Ontario: NHPD. August 18, 2012. Available at: http://webprod.hc-sc.gc.ca/nhpid-bdipsn/monoReq.do?id=1938&lang=eng. Accessed March 21, 2013.
18. Monograph: Holy Basil - Ocimum tenuiflorum - Seed (Under Consultation). Natural Health Products Directorate (NHPD). Ottawa, Ontario: NHPD. August 18, 2012. Available at: http://webprod.hc-sc.gc.ca/nhpid-bdipsn/monoReq.do?id=1937&lang=eng. Accessed March 21, 2013.
19. United States Pharmacopeial Convention. Holy Basil; Powdered Holy Basil; and Powdered Holy Basil Extract. Pharmacopeial Forum. 2012;38(6).
20. European Commission Health & Consumers Directorate. Cosmetic Ingredients and Substances (CosIng^®) Database. Brussels, Belgium: European Commission. Available at: http://ec.europa.eu/consumers/cosmetics/cosing/. Accessed March 21, 2013.
21. Mondal S, Varma S, Bamola VD, Naik SN, Mirdha BR, Padhi MM, et al. Double-blinded randomized controlled trial for immunomodulatory effects of tulsi (Ocimum sanctum Linn.) leaf extract on healthy volunteers. J Ethnopharmacol. 2011;136(3):452-456.
22. Bhat J, Damle A, Vaishnav PP, Albers R, Joshi M, Banerjee G. In vivo enhancement of natural killer cell activity through tea fortified with Ayurvedic herbs. Phyto Res. 2010;24:129-135.
23. Bhattacharyya D, Sur TK, Jana U, Debnath PK. Controlled programmed trial of Ocimum sanctum leaf on generalized anxiety disorders. Nepal Med Coll J. 2008;10(3):176-179.
24. Biswas NR, Gupta SK, Das GK, Kumar N, Mongre PK, Haldar D, et al. Evaluation of Ophthcare^® eye drops—a herbal formulation in the management of various ophthalmic disorders. Phyto Res. 2001;15:618-620.
25. Agrawal P, Rai V, Singh RB. Randomized placebo-controlled single-blind trial of holy basil leaves in patients with non-insulin-dependent diabetes mellitus. Int J Clin Pharmacol Ther. 1996;34:406-409.
26. Ved DK, Goraya GS. Demand and Supply of Medicinal Plants in India. Dehra Dun: India: Bishen Singh Mahendra Pal Singh; 2008.
27. Goldman S. Keeping it Honest^® 2012 Mission Report. Bethesda, MD: Honest Tea. 2012. Available at: www.honesttea.com/community/sustainability/missionreport/pdfs/2012_Mission_Report.pdf. Accessed March 21, 2013.
28. Institut für Marktökologie (IMO). Certified Operators: Fair for Life - Social & FairTrade Certification Programme. Weinfelden, Switzerland: IMO. Accessed: March 21, 2013.
29. Phalada Agro Research Foundation Pvt. Ltd. Certifications. Bangalore, India: Phalada Agro. Available at: www.phaladaagro.com/certifications.html. Accessed March 21, 2013.
30. Tulsi Tea. Sparks, Nevada: Davidson’s Organics. Available at: www.davidsonstea.com/tulsi-tea.aspx. Accessed March 21, 2013.
31. FAQ: Are your products Fair Trade? Boulder, Colorado: Organic India USA. Available at: http://organicindiausa.com/faq/. Accessed March 21, 2013.
32. Natural Health Products Directorate (NHPD). Ocimum tenuiflorum. In: Licensed Natural Health Products Database. Ottawa, Ontario: NHPD. Available at: http://webprod3.hc-sc.gc.ca/lnhpd-bdpsnh/start-debuter.do?lang=eng. Accessed March 21, 2013.