Botany, Geographical Distribution, and Horticultural Information of Turmeric (Curcuma longa)
Turmeric – Botany
Turmeric (Curcuma longa) is a perennial, rhizomatous, herbaceous plant belonging to the ginger family, Zingiberaceae. It typically reaches up to 1 meter in height and features highly branched, yellow to orange, cylindrical, aromatic rhizomes. The leaves of turmeric are alternate, arranged in two rows, and divided into leaf sheath, petiole, and leaf blade. The petiole can be 50 to 115 cm long, and the simple leaf blades are usually 76 to 115 cm long and 38 to 45 cm wide. These are oblong to elliptical in shape, narrowing at the tip.
The inflorescence of turmeric includes stem bracts at the top, with no flowers occurring on these bracts. The hermaphrodite flowers are zygomorphic and threefold, with three sepals and three bright-yellow petals fused into a corolla tube. The fruit capsule of turmeric opens with three compartments.
Turmeric – Geographical Distribution
Turmeric is native to the Indian subcontinent and Southeast Asia. The greatest diversity of Curcuma species is in India, with around 40 to 45 species, followed by Thailand with 30 to 40 species. Other countries in tropical Asia also have numerous wild species of Curcuma. The taxonomy of C. longa is complex, with only specimens from South India being definitively identifiable as C. longa. The species and cultivars in other parts of the world still require further study to establish their identity and relationships.
Turmeric – Horticultural Information
Turmeric requires temperatures between 20 and 30 °C and high annual rainfall to thrive. It is cultivated in tropical and subtropical regions worldwide. The rhizomes are gathered each year, some for propagation in the following season and some for consumption. The rhizomes are used fresh or boiled in water and dried, after which they are ground into a deep orange-yellow powder.
In terms of cultivation, genetic variability and heritable variation are crucial for breeding and improving turmeric genotypes. Studies have shown considerable genetic variability among turmeric genotypes, especially in regions like northeastern India and Pakistan. This variability is essential for the conservation of genetic resources and achieving consistent crop improvement.
References:
1. “Turmeric – Wikipedia” – [Wikipedia](https://en.wikipedia.org/wiki/Turmeric
2. Yadav, R. P., & Tarun, G. “Versatility of turmeric: A review the golden spice of life” – https://scholar.google.com
3. Luiram, S., Barua, P. C., et al. “Genetic Variability Studies of Turmeric (Curcuma longa l.) Genotypes of North Eastern Region of India” – https://dx.doi.org/10.20546/IJCMAS.2018.707.453
4. Jan, H. U., Rabbani, M. A., & Shinwari, Z. “ESTIMATION OF GENETIC VARIABILITY IN TURMERIC (CURCUMA LONGA L.) GERMPLASM USING AGRO-MORPHOLOGICAL TRAITS” – https://scholar.google.com
5. Janani, S. N.M., & Naveenkumar, R. “Review on Detection Methods of Turmeric Disease and Methodology Using Artificial Neural Network” – https://dx.doi.org/10.2139/ssrn.3852629
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History, Traditional Herbal & Culinary Uses of Turmeric (Curcuma longa)
Turmeric – History
Turmeric (Curcuma longa), a perennial, rhizomatous, herbaceous plant, is native to the Indian subcontinent and Southeast Asia. It thrives in environments with temperatures between 20 and 30 °C and high annual rainfall. Historically, turmeric has been a significant part of Ayurveda, Siddha medicine, traditional Chinese medicine, Unani, and various animistic rituals of Austronesian peoples. Initially used as a dye, it later gained prominence for its properties in folk medicine.
The spread of turmeric is closely linked to the spread of Hinduism and Buddhism, as it was used to color the robes of monks and priests. Its presence in regions like Tahiti, Hawaii, and Easter Island before European contact indicates its widespread use and importance. The Austronesian peoples, particularly in Polynesia and Micronesia, used turmeric extensively for both food and dye, suggesting independent domestication events.
Archaeological evidence shows turmeric in Farmana (India) dating between 2600 and 2200 BCE and in a merchant’s tomb in Megiddo, Israel, from the second millennium BCE. It was also noted as a dye plant in Assyrian Cuneiform medical texts from the 7th century BCE. In Medieval Europe, turmeric was known as “Indian saffron.”
Turmeric – Traditional Herbal Uses
Turmeric has been traditionally used for a variety of medicinal purposes. In Northeastern Algeria, for instance, it has been used for treating gastrointestinal, dermatological, and hepatic diseases. The European Medicines Agency in 2019 acknowledged turmeric herbal teas for relieving mild digestive problems like feelings of fullness and flatulence.
In Indian traditional medicine, turmeric is used in various rituals and treatments. For example, in Eastern India, it’s part of the nabapatrika, used in wedding ceremonies across the Indian subcontinent. Turmeric paste is applied to the bride and groom in many Hindu communities as part of pre-wedding festivities.
Despite its widespread traditional use, there is no high-quality clinical evidence supporting the effectiveness of turmeric or curcumin in treating diseases.
Turmeric – Culinary Uses
Turmeric is a key ingredient in many Asian cuisines, known for its mustard-like, earthy aroma and slightly bitter flavor. It’s used in savory dishes and some sweet dishes, like the cake sfouf. In India, turmeric leaf is used to prepare special sweet dishes, patoleo. It’s a principal ingredient in curry powders and is used in various products like canned beverages, dairy products, and sauces.
In South Asian and Middle Eastern cooking, turmeric is used extensively. It’s part of various traditional recipes, like Iranian khoresh, Moroccan spice mix ras el hanout, and South African geelrys (yellow rice). In Southeast Asian cuisines, like Vietnamese, Cambodian, and Indonesian, turmeric is used in numerous dishes, including curries and soups. Turmeric is also used in beverages like “turmeric latte” or “golden milk.”
References:
1. “Turmeric – Wikipedia” – https://en.wikipedia.org/wiki/Turmeric
2. Bouzabata, A., & Boukhari, A. (2014). “Variation in the Traditional Knowledge of Curcuma longa L. in North-Eastern Algeria” – https://scholar.google.com
3. Maurya, R., Verma, R., Kumari, P., & Singh, R. “Medicinal properties of turmeric (Curcuma longa L.): A review” – https://scholar.google.com
4. Jyotirmayee, B., & Mahalik, G. (2021). “Traditional Uses and Variation in Curcumin Content in Varieties of Curcuma-the Saffron of India” – https://dx.doi.org/10.21276/ambi.2022.09.1.rv01
5. Enemor, V., Ogbodo, U. C., Nworji, O. F., Ezeigwe, O., Okpala, C. O., & Iheonunekwu, G. C. (2020). “Evaluation of the Nutritional Status and Phytomedicinal Properties of Dried Rhizomes of Turmeric (Curcuma longa)” – https://dx.doi.org/10.4236/jbm.2020.88015
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Scientific and Medicinal Studies on Turmeric (Curcuma longa)
Turmeric – Overview of Scientific Research
Turmeric, known scientifically as Curcuma longa, is widely recognized for its use as a flavoring agent, medicinal herb, and dye, particularly in Asian countries. The main component of turmeric is curcumin, which has been extensively studied for its diverse properties, including anti-inflammatory, antioxidant, antimutagenic, and antimicrobial effects. However, there is a need for more information on the pharmacokinetics, bioavailability, and food content of curcumin. The concentration of curcumin in turmeric and curry powders varies, raising questions about its sufficiency to affect biological activities and cancer risk.
Turmeric – Medicinal Properties and Applications
Turmeric has been a staple in Ayurvedic and Chinese medicine, used as an anti-inflammatory agent and for treating digestive disorders and liver problems. The active ingredient, curcumin, has been the focus of various medicinal properties. Research has shown that turmeric is effective in managing diabetes, various malignant diseases, Alzheimer’s disease, and other chronic conditions. Its use in traditional medicine spans from being a natural antiseptic and disinfectant to aiding digestion and treating skin irritations.
Turmeric – Correlation and Path Analysis in Turmeric
Studies have been conducted to understand the association between different characteristics of turmeric and their effect on yield. These studies are crucial for selecting the best variety for curcumin extraction. Correlation and path analysis help in understanding the impact of different characters on the yield of turmeric.
Turmeric – Genetic Variability and Agro-Morphological Traits
Turmeric’s genetic variability is significant for its cultivation and improvement. Studies on turmeric genotypes from different geographical regions, like northeastern India and Pakistan, have shown considerable variability in agro-morphological traits. This variability is essential for breeding programs aimed at improving yield and quality.
Turmeric – Turmeric in Modern Medicine
The potential of turmeric and its constituents in the development of modern medicine for treating various diseases is being increasingly recognized. Curcumin’s wide range of activities, including its role as an antioxidant, anti-inflammatory, and anti-cancer agent, makes it a promising candidate for therapeutic applications. Turmeric has also been used as a household remedy for respiratory ailments and as an immunity booster, especially relevant during the ongoing pandemic.
References:
1. Yadav Ashwani Kumar, et al. “ON: TURMERIC (CURCUMA LONGA)” – https://scholar.google.com
2. K. D. K. Chitra, R. V. V. Ambethgar. “Correlation and Path Analysis Studies in Turmeric (Curcuma longa)” – https://dx.doi.org/10.20546/ijcmas.2021.1010.039
3. H. Dev, V. Sharma. “Correlation Studies in Turmeric (Curcuma longa L.)” – https://dx.doi.org/10.20546/ijcmas.2020.908.346
4. J. Sahoo, et al. “The Golden Spice Turmeric (Curcuma longa) and Its Feasible Benefits in Prospering Human Health—A Review” – https://dx.doi.org/10.4236/AJPS.2021.123030
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Phytochemistry of Turmeric (Curcuma longa)
Turmeric – Overview of Phytochemical Composition
Turmeric, scientifically known as Curcuma longa, is a perennial plant used extensively in folk medicine. The phytochemical profile of turmeric is rich and diverse, contributing to its wide range of medicinal properties. The primary bioactive constituent of turmeric is curcumin, which is part of a group of compounds known as curcuminoids. These compounds are responsible for the plant’s characteristic yellow color and are key to its pharmacological activities.
Turmeric – Curcuminoids and Other Compounds
Curcuminoids are a group of fat-soluble polyphenolic compounds that include curcumin, desmethoxycurcumin, and bisdemethoxycurcumin. Curcumin (
deferulolyl methane), the primary curcuminoid in turmeric, accounts for approximately 77% of the curcuminoid content and is known for its powerful anti-inflammatory effects and strong antioxidant properties. Besides curcuminoids, turmeric is also a source of polyphenols, a category of plant compounds that offer various health benefits, including antioxidant activity and potential protection against heart disease, type 2 diabetes, and certain cancers.
Turmeric also contains:
Polyphenols: Turmeric is a source of various polyphenols, which are plant compounds known for their health benefits, including antioxidant properties.
Flavonoids and Glycosides: These compounds are known for their beneficial effects on health, including anti-inflammatory and antioxidant activities.
Alkaloids: Alkaloids are naturally occurring chemical compounds that contain basic nitrogen atoms.
Tannins: Tannins are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds.
Saponins: These are a class of chemical compounds found in particular abundance in various plant species.
Phytosterols: These are plant-derived sterols that have a structure similar to cholesterol and are known for their health benefits.
Essential Oils: Turmeric contains various essential oils that contribute to its aroma and medicinal properties.
Carbohydrates and Proteins: These are basic nutrients found in turmeric, contributing to its nutritional value.
Amino Acids: Turmeric contains various amino acids, which are the building blocks of proteins.
Phenolic Compounds: These are a class of chemical compounds characterized by the presence of phenol structural units.
Gums and Mucilages: These are polysaccharides that have a variety of functional and therapeutic properties.
Turmeric – Pharmacological Activities
The pharmacological activities of Curcuma longa, attributed to its phytochemicals, include anticancer, antidiabetic, anti-osteoarthritis, antidiarrheal, cardioprotective, antioxidative, neuroprotective, hepatoprotective, antimicrobial, renoprotective, and anti-inflammatory effects. These activities have been demonstrated in various in vitro and in vivo studies.
Turmeric – Extraction and Analysis of Phytochemicals
The extraction and analysis of essential phytochemicals from turmeric involve the use of solvents like acetone, methanol, ethanol, and chloroform. Techniques such as qualitative phytochemical screening, UV-Visible spectrophotometry, high-performance liquid chromatography (HPLC), and antimicrobial testing are employed to analyze the polyphenolic and curcuminoid content and to evaluate the antimicrobial activity of turmeric.
Turmeric – Potential for Pharmaceutical Development
The diverse phytochemical composition of Curcuma longa makes it a promising candidate for exploitation by pharmaceutical industries in developing new therapeutic agents. However, there is a need for more human clinical trials and quality control studies to establish effective and safe doses of turmeric and its bioactive constituents for treating various diseases.
References:
1. E. Iweala, et al. “Curcuma longa (Turmeric): Ethnomedicinal Uses, Phytochemistry, Pharmacological Activities and Toxicity Profiles- A Review” – https://dx.doi.org/10.1016/j.prmcm.2023.100222
2. S. Chhimwal, et al. “Antimicrobial activity of Curcuma longa Along with its Total Polyphenolic and Curcuminoid Content” – https://dx.doi.org/10.51129/ujpah-2021-31-2(10)
3. Songtao Liu, et al. “A review: The phytochemistry, pharmacology, and pharmacokinetics of Curcumae Longae Rhizoma (Turmeric)” – https://dx.doi.org/10.4103/2311-8571.351523
4. V. Ranganathan, et al. “Evaluation of curcumin compound from methanolic extracts of Curcuma longa by high performance thin layer chromatography” – https://dx.doi.org/10.22271/PHYTO.2020.V9.I2AF.11138
5. S. Salma, et al. “Qualitative phytochemical analysis of eight turmeric (Curcuma longa L) cultivars grown in various geographical locations of India with six extracts – A comparative study” – https://dx.doi.org/10.1016/j.matpr.2022.04.641
6. M. Patle, et al. “A REVIEW ON IMPORTANCE OF PHYTOCHEMICAL AND PHARMACOLOGICAL SIGNIFICANCE OF TURMERIC (CURCUMA LONGA)” – https://scholar.google.com
7. Samaneh Noori, et al. “Phytochemical Study and Recognition of Curcuminoids of Turmeric (Curcuma longa L.) Extract and Comparison of the Flavonoid and Flavanol Content Utilizing Different Extraction Methods” – https://dx.doi.org/10.29252/SJIMU.26.6.86
8. A. Oluwafemi, et al. “Phytochemical Screening, Nutritional Composition, and Antioxidant Activities of Turmeric (Curcuma longa) Found in Ado-ekiti, Nigeria” – https://dx.doi.org/10.9734/jalsi/2022/v25i130278
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Turmeric – Safety Profile
Turmeric, known scientifically as Curcuma longa, is a widely used herb in traditional medicine and cooking. Turmeric is a beneficial herb with a good safety profile when used appropriately. While it is celebrated for its therapeutic benefits, including anti-inflammatory and antioxidant properties, understanding its safety profile and potential contraindications is crucial for responsible use, especially in therapeutic doses.
Turmeric and its major constituent, curcumin, are generally recognized as safe substances. They are nonmutagenic and nongenotoxic, indicating a low risk of causing genetic mutations or DNA damage. In human studies, turmeric has been found to be safe at doses up to 6 grams per day orally for durations of 4 to 7 weeks. However, some individuals may experience gastrointestinal upsets at higher doses. Oral bioavailable formulations of curcumin have been deemed safe for human consumption at a dose of 500 mg twice daily for 30 days.
Turmeric Contraindications:
While turmeric is safe for most individuals, there are specific situations where its use may be contraindicated or require caution:
1. Pregnancy and Lactation: The safety of turmeric during pregnancy and lactation has not been thoroughly studied. Therefore, it is advisable to avoid high doses during these periods.
2. Gallbladder Issues: Turmeric can exacerbate gallbladder problems. Individuals with gallstones or bile duct obstructions should avoid turmeric supplements.
3. Blood-Thinning Medications: Turmeric has natural blood-thinning properties. Caution is advised when using it alongside anticoagulant medications like warfarin.
4. Diabetes Medications: Since turmeric can lower blood sugar levels, it should be used cautiously by individuals on diabetes medication to avoid hypoglycemia.
5. Gastrointestinal Disorders: High doses of turmeric may irritate the gastrointestinal tract. Individuals with GERD, ulcers, or other digestive issues should use turmeric cautiously.
6. Iron Absorption: Turmeric can interfere with iron absorption. Individuals with iron deficiency should consult a healthcare provider before using turmeric supplements.
References:
1. Vahid Soleimani, et al. “Turmeric (Curcuma longa) and its major constituent (curcumin) as nontoxic and safe substances: Review” – https://dx.doi.org/10.1002/ptr.6054
2. D. Turck, et al. “Safety of tetrahydrocurcuminoids from turmeric (Curcuma longa L.) as a novel food pursuant to Regulation (EU) 2015/2283” – https://dx.doi.org/10.2903/j.efsa.2021.6936
3. M. Selvi, et al. “Safety of NR-INF-02, an Extract of Curcuma Longa Containing Turmerosaccharides, in Healthy Volunteers: A Randomized, Open-label Clinical Trial.” – https://pubmed.ncbi.nlm.nih.gov/32827412
4. Peixoto Erika Cosendey Toledo De Mello, et al. “Efficacy and Safety of Curcuma longa L: Relevant Results for Cancer Treatment” – https://dx.doi.org/10.36959/745/413