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Curcumin Content of Turmeric and Curry Powders



Curcumin, derived from the rhizome curcuma longa, is one of the primary ingredients in turmeric and curry powders that are used as spices in Middle Eastern and Asian countries, especially on the Indian subcontinent. More recently, laboratory studies have demonstrated that dietary curcumin exhibits various biological activities and significantly inhibits colon tumorigenesis and tumor size in animals. Curcumin displays both anti-inflammatory and antioxidant properties, giving it the potential to be considered in the development of cancer preventive strategies and applications in clinical research. Experimental studies have shown the biological activities of the compound, but much more information on pharmacokinetics, bioavailability, and food content are needed. Whether the amount of curcumin in turmeric and curry powders is sufficient to suggest effects on biological activities and cancer risk is unknown. To determine and compare the quantitative amounts of curcumin that are present in several brands of turmeric and curry powders, a high performance liquid chromatography technique was used to analyze 28 spice products described as turmeric or curry powders and two negative controls. Pure turmeric powder had the highest curcumin concentration, averaging 3.14% by weight. The curry powder samples, with one exception, had relatively small amounts of curcumin present, and the variability in content was great. The curcumin content of these seasoning products that are consumed as a component of the diet should be considered in evaluating baseline tissue concentration and response to curcumin supplementation, which is under study in chemoprevention trials.
Curcumin Content of Turmeric and Curry Powders
Reema F. Tayyem, Dennis D. Heath, Wael K. Al-Delaimy, and Cheryl L. Rock
Abstract: Curcumin, derived from the rhizome curcuma
longa, is one of the primary ingredients in turmeric and curry
powders that are used as spices in Middle Eastern and Asian
countries, especially on the Indian subcontinent. More re-
cently, laboratory studies have demonstrated that dietary
curcumin exhibits various biological activities and signifi-
cantly inhibits colon tumorigenesis and tumor size in ani-
mals. Curcumin displays both anti-inflammatory and antiox-
idant properties, giving it the potential to be considered in
the development of cancer preventive strategies and applica-
tions in clinical research. Experimental studies have shown
the biological activities of the compound, but much more in-
formation on pharmacokinetics, bioavailability, and food
content are needed. Whether the amount of curcumin in tur-
meric and curry powders is sufficient to suggest effects on bi-
ological activities and cancer risk is unknown. To determine
and compare the quantitative amounts of curcumin that are
present in several brands of turmeric and curry powders, a
high performance liquid chromatography technique was
used to analyze 28 spice products described as turmeric or
curry powders and two negative controls. Pure turmeric
powder had the highest curcumin concentration, averaging
3.14% by weight. The curry powder samples, with one excep-
tion, had relatively small amounts of curcumin present, and
the variability in content was great. The curcumin content of
these seasoning products that are consumed as a component
of the diet should be considered in evaluating baseline tissue
concentration and response to curcumin supplementation,
which is under study in chemoprevention trials.
Turmeric, a derivative of the plant, curcuma longa,a
member of the ginger family, is a spice commonly used in
Middle Eastern countries and other regions of Asia. It has a
long history of use in herbal remedies, particularly in China,
India, and Indonesia. The major curcuminoids, curcumin,
demethoxycurcumin, and bisdemethoxycurcumin, occur
naturally in these curcuma species. Curcumin, an active com-
ponent of turmeric, is a yellow pigment that has been isolated
from the ground rhizome part of the curcuma plant species,
zingiberaceae (1,2).
Curcumin has been shown to have several biological ef-
fects, exhibiting anti-inflammatory (3–6), antioxidant
(5,7–10), and hypolipidemic (11–13) activities. Curcumin
has also been studied extensively as a chemopreventive agent
in several cancers (14–17). Additionally, it has been sug-
gested that curcumin may contribute in part to the lower rate
of colorectal cancer in Asian countries compared to rates in
other countries (18).
Curcumin exhibits relatively low oral bioavailability in
humans and rats and may undergo extensive intestinal metab-
olism (1,5,19); absorbed curcumin undergoes rapid first-pass
metabolism and excretion in the bile (1,5,15,19–20). In rats,
curcumin absorption from the intestine has been reported to
be about 60% (20). In contrast to the report of low bio-
availability in most human studies, Cheng et al. (21) reported
that a high oral dose of curcumin (0.5–8 g/day) for 3 mo re-
sulted in increased serum curcumin concentration to a peak
at approximately 1–2 h, followed by a decline within 12 h af-
ter consumption. A dose of 8 g/day resulted in a peak serum
concentration of 1.75 ± 0.80 (mean ± SD) µM in that study.
Traditionally turmeric is used in various cuisines for fla-
vor as well as a coloring agent for foods such as rice, yogurt,
and chicken. Turmeric may also be used by itself or in combi-
nation with other mixed spices. Curry powder is a mixed
spice with turmeric as one of the principal ingredients.
Curcumin content is reported to vary from one batch of
turmeric powder to another. The percentage has been esti-
mated to be between 1.06% and 5.70% in 4 different “com-
mercially available” turmeric samples (22). In this prior anal-
NUTRITION AND CANCER, 55(2), 126–131
Copyright © 2006, Lawrence Erlbaum Associates, Inc.
R. F. Tayyem is affiliated with the Clinical Nutrition and Dietetics Department, Allied Health Sciences Faculty, The Hashemite University, Al-Zarqa’, Jor-
dan. D. D. Heath and W. K. Al-Delaimy are affiliated with the Cancer Prevention and Control Program, Moores Cancer Center, University of California, San
Diego, La Jolla, CA 92093. C. L. Rock is affiliated with the Department of Family and Preventive Medicine, University of California, San Diego, La Jolla, CA
ysis (22), however, it was not clear if the turmeric powders
were the types available to the commercial blenders of spices
or to the consuming public. Several studies have shown that
soil factors, including nutrients and level of acidity as well as
the genus diversity, may affect the content of curcumin in
plants that are the source of turmeric (23–24). Curry blends
vary widely from one manufacturer to another, and numerous
blends are available in shops and markets. Curry blends are
usually composed of coriander seeds, turmeric, chillies,
cumin seeds, fenugreek seeds, fennel seeds, trifala and
nagkeser (fragrant spices), cloves, cassia, garlic, curry
leaves, and salt.
To our knowledge there are few data available on the
curcumin content of turmeric and curry powders. The aim of
this study was to quantitate curcumin in various sample
blends of turmeric and curry powders. These blends of spices
were purchased in several grocery stores in the Riverside, Or-
ange, and San Diego Counties of Southern California. Infor-
mation about the curcumin content of turmuric and curry
powders is a useful first step toward estimating the amount of
curcumin that could potentially be obtained from the diet and
specific food choices.
Materials and Methods
Chemicals, Reagents,
and Sample Preparation
Turmeric, curry powders, and cardamon were purchased
from local grocery stores, including some that catered to the
Middle Eastern and Asian Indian Communities, in Southern
Acetonitrile, methanol, acetic acid, deionized water were
purchased from Fisher Scientific (Pittsburg, PA). All re-
agents were of analytical grade. Mobile phase reagent con-
taining the following ratio (volume:volume) mixture of
acetonitrile:methanol:water:acetic acid (40:23:36:1) was
prepared according to the method of Heath et al. (25). Five
mg of each powdered spice were weighed on a Mettler model
AB204 balance (Mettler Instrument, Hightstown, NJ) and
dissolved in methanol, making a precise final volume of 5.0
mL with mobile phase reagent to achieve the desired concen-
tration, 1,000 µg/mL. Next, the dissolved solution was cen-
trifuged in a bench top Centifuge (Sorvall RT 6000D,
Dupont, Waltham, MA). An aliquot was removed and further
diluted prior to column injection.
Curcumin was separated and quantitated by isocratic high
performance liquid chromatography (HPLC), using ultravio-
let detection at a wavelength of 262 nm. An aliquot (50 µL),
was injected onto a reversed-phase column, and the HPLC
system consisted of a 410 auto-sampler with refrigeration
unit, a 9050 UV visible detector, and a 9010 solvent delivery
system with Star 6.30 Chromatography Software (Varian,
Walnut Creek, CA). Chromatographic separation was ac-
complished using a Waters SymmetryShield 3.9 × 150 mm,
18 column (Waters, Milford, MA). The column was
coupled to an Alltech absorbosphere 30 × 4.6 mm C18 guard
column (Alltech Associates, Deerfield, IL). The flow rate
was 1.0 mL/min.
The quantitation of curcumin is by peak area and is based
on a standard curve in a methanol matrix, generated by using
pure external standard. A linear curve is generated from a
single analysis of six different standard concentrations. All
samples were analyzed in triplicate.
In our analytical processing of the turmeric and curry
powders achieved by dissolving the powders in analytical
grade methanol, we did not detect any interference with the
peak of interest, curcumin. The chromatographic retention
time of 5.4 min was consistent with and identical to the
known curcumin external standard.
The curcumin contents of the selected brands of turmeric
and curry powders are shown in Table 1. Product identifica-
tion information, including brand names, ingredients, and
manufacturers is shown in Table 2. We found that pure tur-
meric powder had the highest curcumin concentration, aver-
aging 3.14% by weight. The curry powder samples, with one
exception, had relatively small amounts of curcumin present,
and the variability in content was great across products.
As shown in Tables 1 and 2, labels for the turmeric and
curry powders identified several countries of origin: India,
Pakistan, Japan, Taiwan, Jamaica, Sri Lanka, Canada, and
the United States. Several samples were labeled and identi-
fied with local market vendors in the Southern California cit-
ies of Riverside, San Diego, and Los Angeles. Based on label
details (Table 2), all turmeric powders, regardless of country
where manufactured or processed, were described as con-
taining turmeric powder only. We observed that the two tur-
meric powders with the highest percentage of curcumin per
dry weight (3.14% and 2.46%) had label markings indicating
that they were prepared or produced in or were a product of
the United States. In the turmeric powders, the average
curcumin content (percentage of the dry weight), was 1.51%,
with the lowest at 0.58% and the highest at 3.14%. The dif-
ference between the lowest and the highest curcumin content
in the analyzed turmeric powder was 5.4-fold.
In our analysis of the spices labeled as curry powders (Ta-
ble 1), the powders with the highest percentage of curcumin,
0.58% and 0.53%, were identified as products of Canada and
Japan, respectively. In the spices labeled as curry powder, the
average curcumin content was 0.28%, with a range of 0.05%
to 0.58%. The difference between the lowest and highest
curry powder blends was 11.6-fold. Turmeric, peppers, cori-
ander, and fenugreek were the most commonly listed ingredi-
ents in the curry powders.
Two spices, listed in Table 2, were selected and measured
originally as negative controls for curcumin, because these
products would not be expected to contain curcumin. In the
case of the Massala product, turmeric, curry, or curcumin
Vol. 55, No. 2 127
were not named in the ingredients listed in the label. How-
ever, a constituent eluted from the column with the chro-
matographic retention time consistent with curcumin, and it
was noted that the label ingredients included the phrase
“other spices.” Thus, it is possible that turmeric or curry pow-
der may have been included in that spice blend. In cardamon,
a negative control, curcumin was not detected. The analytical
drift as measured by the coefficient of variation in all but two
instances was less than 3%. The analytical drift in two sam-
ples was less than 9%.
Curcumin [1, 7-bis (4-hydroxy-3-methoxyphenyl)-1,
6-heptadiene-3, 5-dione] is the major yellow pigment ex-
tracted from turmeric, a commonly used spice, derived from
the rhizome of the herb curcuma longa Linn (1,25). It is a nat-
urally occurring polyphenolic phytochemical. There has
been considerable public and scientific interest in the use of
phytochemicals derived from the diet to reduce risk and pro-
gression of major chronic diseases (5), and turmeric has been
used in Asian medicine since the 2nd millennium BC
(5,26–27). In laboratory animal studies, curcumin, a major
component of turmeric, has been shown to have the potential
to contribute to the prevention of cancer and other chronic
diseases due to various biological activities (25,28–32). In
spite of suggestive laboratory evidence and current interest in
a potential role for curcumin as a chemopreventive constitu-
ent of the diet, food content data for this compound are not
available, and results of analysis of curcumin content of
spices or foods are scarce.
Anecdotal evidence suggests that consumption of tur-
meric occurs on a daily basis in Indian and other Asian com-
munities. In a review on the topic of curcumin, Sharma et al.
(5) reported consumption of 1.5 g/person/day in certain
Southeast Asian communities. However, no information was
given as to the number sampled or the manner in which they
were queried in that report. The regular consumption of tur-
meric has been suggested as a possible factor promoting the
lower rate of cancer that has been observed in these commu-
nities when compared to cancer rates in countries such as the
United States (18,33). However, without quantitative data
that would allow disentangling the associations between
curcumin intake and other influencing factors (including
nondietary etiological factors), a cause and effect relation-
ship cannot be assumed.
Thus, accurate information on the quantity of curcumin
provided by turmeric and curry powders or other sources of
curcumin in the diet would be useful to more accurately as-
sess the intake of curcumin and to better examine possible
chemopreventive effects. It has been reported by Sharma et
al. (5) that over 2,400 metric tons of turmeric is imported an-
nually into the United States for consumer use, which sug-
128 Nutrition and Cancer 2006
Table 1. Curcumin Content of Samples of Turmeric and Curry Powders
Spice Type Identifying Number Curcumin Mean (SD) (µg/mL) Curcumin Content (percentage of dry weight)
Turmeric Powder 4 9.77 (0.058) 0.98
8 5.77 (0.380) 0.58
11 12.53 (0.058) 1.25
20 10.42 (0.058) 1.04
21 19.97 (0.054) 2.00
24 31.37 (0.038) 3.14
28 10.75 (0.050) 1.07
29 10.46 (0.039) 1.05
30 24.47 (0.014) 2.46
Curry Powder 1 5.33 (0.053) 0.53
3 1.90 (0.000) 0.19
5 3.50 (0.000) 0.35
7 1.10 (0.000) 0.11
9 0.50(0.000) 0.05
10 3.13 (0.058) 0.31
12 1.80 (0.000) 0.18
13 1.00 (0.000) 0.10
14 2.30 (0.000) 0.23
15 1.10 (0.000) 0.11
16 3.70 (0.100) 0.37
17 1.10 (0.000) 0.11
18 2.70 (0.000) 0.27
19 2.73 (0.026) 0.27
22 2.65 (0.019) 0.26
23 4.96 (0.430) 0.49
25 5.81 (0.150) 0.58
26 4.11 (0.047) 0.41
27 5.00 (0.000) 0.50
Vol. 55, No. 2 129
Table 2. Product Identification Information
ID Name Ingredients Brand or Manufacturer
1 Sand B Oriental Curry Powder Turmeric, coriander, fenugreek, cumin, red
pepper, black pepper, cinnamon, ginger,
star anise, cloves, cardamon, fennel,
nutmeg, laurel leaves, allspice, garlic
S&B Foods Inc., Tokyo 103-0026, Japan;
Product of Japan; Use in lamb, beef,
chicken, shrimp, fish, fried rice and egg
2 Cardamon Powder Bubuk Kapollaga BOT Cardamon Jara Brand; Packed for WIRA Corp., 168
Mason Way Unit A-6, CA 91746. USA
3 Curry Power India Coriander, turmeric, cumin, other spices TOMAX ENTERPRISE Co., Ltd., No.1
Industrial South 6th Rd., Natou City,
4 Sadaf Powder Turmeric “Curcuma En Polvo” Turmeric comes from the dried roots of
curcuma longa spice plant, grows in India
and China
Sadaf Brand, Soofer Co., Inc., Los Angeles,
CA 90058;
5 Tampico Curry Powder Spices, turmeric, salt, red pepper Tampico Spice Co., Inc. 5941 So. Central
Ave., Los Angeles, CA 90001
6 Sadaf Seasoning Garam Massala Coriander, black pepper, cinnamon, rock salt,
cardamon, other spices
Sadaf Brand, Soofer Co., Inc., Los Angeles,
CA 90058;
7 Sadaf Hot Curry Powder Chillies, black pepper, cayenne, fenugreek,
curry leaves, ginger, turmeric
Sadaf Brand, Soofer Co., Inc., Los Angeles,
CA 90058;
8 AHMED Turmeric Powder Turmeric powder AHMED Food International, 11-24, Sector
C-111, K.E.P.Z., Karachi 75150; Product
of Pakistan
9 AHMED Curry Powder (seasoning mix for
meat/vegetable curry)
Red chilli, coriander, turmeric, black pepper,
ginger, salt, cinnamon, cumin seeds,
cardamon, mace, garlic (fresh buds), bay
leaves, onion
AHMED Food International, 11-24, Sector
C-111, K.E.P.Z., Karachi 75150; Product
of Pakistan
10 Day Street Market Fresh Fruits and
Vegetables Curry Powder Curry Molido
Not listed Halal Meats Grocery and Produce, 12125
Day St. Suite F-301, Moreno Valley, CA
92557, Tel: (909) 682 3536
11 Day Street Market Fresh Fruits and
Vegetables Turmeric
Turmeric powder Halal Meats Grocery and Produce, 12125
Day St. Suite F-301, Moreno Valley, CA
92557, Tel: (909) 682 3536
12 Blue Mountain Jamaican Curry Powder Coriander, cumin, fenugreek, turmeric, anise,
red pepper
Blue Mountain Jamspice
13 Hot Curry Powder Coriander, turmeric, salt, fennel, chilli,
cumin, fenugreek, garlic, cassia, cloves,
anise, pepper, cassia buds, curry leaves
Laxmi Brand; Product of India
14 Rani (mild curry powder) Chilli, coriander, cumin, mustard, fenugreek,
black pepper, curry leaves, ginger turmeric
Rani Brand; California
15 Green Label-Madras Curry Powder H.E. The
Gov. of Bombay
Coriander, turmeric, salt, fennel, chilli, black
pepper, fenugreek, garlic, cumin, bay
leaves, ginger, cassia
Ship Brand
16 Larich Roasted Curry Powder Coriander, fennel, cumin, fenugreek,
cinnamon, nutmeg, cardamom, cloves,
curry leaves
Larich Brand; Product of Sri Lanka
17 Rajah Brand Hot Madras Curry Powder Coriander, turmeric, mustard, chilli, bengal
gram, cumin, fenugreek, pepper, garlic,
salt, fennel, poppy seeds, curry leaves
Rajah Brand
18 Schilling Indian Curry Powder (mild) Coriander, fenugreek, turmeric, cumin, black
pepper, bay leaves, celery seeds, nutmeg,
cloves, onion, red pepper
Schilling Brand
19 Madrecita Curry Powder Not listed Madrecita 8280, Clairemont Mesa Blvd Suite
140, San Diego, CA, 92111
20 Madrecita Turmeric Curcuma longa, ground turmeric Madrecita 8280, Calrimont Mesa Blvd Suite
140, San Diego, CA 92111
21 Flower Brand Turmeric Powder HALDI Turmeric powder Flower Brand MK Agro Exports
Mumbai-India, SAHA Distributors,
Tel: (310) 719 1011 Fax: (310) 719 1112;
Product of India
22 Flower Brand Curry Powder Hot (mixed
Coriander, fenugreek, turmeric, cumin, chilli,
mustard, other spices
Flower Brand MK Agro Exports
Mumbai-India, SAHA Distributors,
Tel: (310) 719 1011 Fax: (310) 719 1112;
Product of India
gests that the amount of curcumin consumed could have bio-
logical effects depending on food choices and use of
curcumin-containing spices.
Clinical trials are currently examining the pharmaco-
kinetic properties and effects of curcumin supplementation
on various biological activities that are relevant to the risk
and progression of cancer (34). Knowledge of curcumin in-
take from the diet and food choices would be useful in de-
signing and interpreting the results of the response in these
studies. For example, higher tissue concentrations and expo-
sure at baseline would be useful in interpreting the response
to supplementation. The wide variation in curcumin content
of the several brands of turmeric and curry powders that was
observed in this study suggests that considerable variability
in tissue concentration could exist across subjects and groups
involved in these studies.
Curcumin content of turmeric and curry powders is highly
variable. Pure turmeric powder has the highest curcumin
concentration, and relatively small amounts of curcumin are
present in curry powder samples. As a first step toward quan-
tifying curcumin intake from the diet, these data contribute to
knowledge that would be useful in the interpretation of find-
ings relating curcumin intake to cancer risk and prevention
and to the response to curcumin supplementation in
pharmacokinetic studies and chemoprevention trials.
Acknowledgments and Notes
The first author would like to acknowledge the L’OREAL-UNESCO or-
ganization for the Women in Science Award Scholarship, which provided
some funding for this project. We also thank Fatima Khwaja for her impor-
tant contributions to this project. This project was completed at the Univer-
sity of California, San Diego, in La Jolla, CA. Address correspondence to D.
Heath, MS, UCSD Cancer Prevention and Control Program, 3855 Health
Sciences Drive, Dept. 0803, La Jolla, CA 92093-0803. Phone:
858–822–1123. FAX: 858–822–1497. E-mail:
Submitted 10 May 2006; accepted in final form 24 May 2006.
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23 Tone’s Curry Powder Spices, turmeric, salt, red pepper, spice
Tone Brothers, Inc., Ankeny, IA 50021,
24 Tone’s Ground Turmeric Turmeric powder Tone Brothers, Inc., Ankeny, IA 50021,
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26 Spice Supreme Curry Powder Mustard, turmeric, coriander, cumin, cloves Gel Spice Co., Inc., Bayonne, NJ 07002;
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27 EL GUAPO Curry Powder Coriander, fenugreek, turmeric, cumin, black
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... in contrast with the previous studies, this present trial used 3000 mg of turmeric powder, which contained 200 mg of curcumin, a dose similar to other studies that have used between 30 mg to 2000 mg of curcumin in a capsule among an obese population [53][54][55]. however, it is important to note that the curcumin amount in turmeric powder can vary significantly between treatments [56]. a quantitative study compared the amounts of curcumin present in several brands of turmeric and curry powder using hPlc. ...
... a quantitative study compared the amounts of curcumin present in several brands of turmeric and curry powder using hPlc. turmeric powders had 3.14% curcumin by weight on average, whereas curry powders had less than 1% on average, with great variability [56]. another important factor regarding dose is curcumin's bioavailability once ingested. ...
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Background: Obesity is considered a low-grade chronically inflamed state that contributes to communicable chronic diseases. This inflammation may be modulated by consuming spices like turmeric daily. However, few studies have looked at the inclusion of spice within whole foods. Objective: The purpose of this feasibility pre/posttrial was to assess the influence of turmeric in a muffin on salivary IL-6 and CRP in adults who were obese. Methods: Participants consumed one, 60-gram muffin containing 3 g turmeric for 10 days. Participants provided a urinary sample at baseline, a 2-ml saliva sample, and a 30-day food frequency and spice consumption questionnaire at baseline and post-trial. A one-sample t-test was conducted using SAS v 9.4 with significance determined at p < 0.05. Results: A total of 14 participants, average BMI of 32.16 kg/m2 with 10 identifying as female, completed the trial after 5 dropped due to various reasons. The visit lengths and collection of data with participants adhering to the instructions were deemed a success. There was a significant decrease in salivary IL-6 (p = 0.03) but no statistical difference in salivary CRP (p = 0.46). Participants consumed fruits and vegetables at least once daily, chicken and eggs 5-6 times per week, and beef, pork, and fish at least once per week. Participants consumed chili pepper, garlic, cinnamon, cilantro, and ginger at least once per week. No changes were observed in dietary/spice habits during this trial. Conclusion: The feasibility pre/post study revealed that consumption of a muffin with turmeric reduced at least salivary IL-6 in 10 days. Modifications to the study design such as lengthier trial time to assess the impact of this muffin on CRP is necessary prior to implementing larger-scale randomized control trials.
... For example, a 3-oz serving of tuna fish, which is high in nicotinamide, contains a niacin concentration of about 211.5 mg/L (18) (niacin amounts can be used to approximate nicotinamide amounts because niacin is converted into nicotinamide in the body (19)). In addition, turmeric powder, the South Asian spice that is high in curcumin, contains a curcumin concentration of 20331 mg/L (20,21). Although the concentration of curcumin is extremely high, turmeric is a powder, so it is generally added to dishes in small quantities during daily practice. ...
Parkinson’s disease is a neurodegenerative disease that causes the death of dopamine-producing neurons. It is associated with the accumulation of a protein called α-synuclein, which is responsible for the death of the neurons and causes severe motor disorders. Current drugs have significant side effects and only treat symptoms rather than the actual disease. Our study aims to explore the anti-Parkinsonian effects of curcumin and nicotinamide, which are two compounds derived from natural sources. Curcumin and nicotinamide were chosen for their health benefits and properties that suggest anti-Parkinsonian potential. In our study, we used the model organism C. elegans, a nematode. Our strain expresses human α-synuclein fused to yellow fluorescent protein. The study examined the effect of curcumin and nicotinamide on the fluorescence intensity of α-synuclein in C. elegans and compared it to the effect of Levodopa (the commercial drug most commonly prescribed to Parkinson’s patients). We used two methods to measure fluorescence. In our first method, the worms were imaged after treatment under a fluorescence microscope, and fluorescence was quantified using ImageJ. In the second method, the fluorescence of the worms was measured after treatment using a microplate reader. Our study showed that curcumin and nicotinamide reduce the fluorescence intensity of α-synuclein as effectively as levodopa in C. elegans. This suggests that curcumin and nicotinamide may affect α-synuclein levels in other organisms and should be further investigated as treatments for Parkinson’s disease. These findings also encourage further investigations on other natural compounds as possible therapies against Parkinson’s disease.
... Similarly, lenticin ( Figure 2F) is derived from the ingestion of lentils [22], explaining why we only found it in vegans. Other examples, could be citrinin ( Figure 2G) found mainly in omnivore samples, as it derives from cheese production [20]; and curcumin ( Figure 2H) found mainly in vegan samples, as it derives from turmeric ingestion [23]. Furthermore, the results obtained can be used to track the metabolic changes in specific pathways, like the purine metabolism pathway ( Figure S6). ...
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To gain confidence in results of omic-data acquisitions, methods must be benchmarked using validated quality control materials. We report data combining both untargeted and targeted metabolomics assays for the analysis of four new human fecal reference materials developed by the U.S. National Institute of Standards and Technologies (NIST) for metagenomics and metabolomics measurements. These reference grade test materials (RGTM) were established by NIST based on two different diets and two different samples treatments, as follows: firstly, homogenized fecal matter from subjects eating vegan diets, stored and submitted in either lyophilized (RGTM 10162) or aqueous form (RGTM 10171); secondly, homogenized fecal matter from subjects eating omnivore diets, stored and submitted in either lyophilized (RGTM 10172) or aqueous form (RGTM 10173). We used four untargeted metabolomics assays (lipidomics, primary metabolites, biogenic amines and polyphenols) and one targeted assay on bile acids. A total of 3563 compounds were annotated by mass spectrometry, including 353 compounds that were annotated in more than one assay. Almost half of all compounds were annotated using hydrophilic interaction chromatography/accurate mass spectrometry, followed by the lipidomics and the polyphenol assays. In total, 910 metabolites were found in at least 4-fold different levels in fecal matter from vegans versus omnivores, specifically for peptides, amino acids and lipids. In comparison, only 251 compounds showed 4-fold differences between lyophilized and aqueous fecal samples, including DG O-34:0 and methionine sulfoxide. A range of diet-specific metabolites were identified to be significantly different between vegans and omnivores, exemplified by citrinin and C17:0-acylcarnitine for omnivores, and curcumin and lenticin for vegans. Bioactive molecules like acyl alpha-hydroxy-fatty acids (AAHFA) were differentially regulated in vegan versus omnivore fecal materials, highlighting the importance of diet-specific reference materials for dietary biomarker studies.
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Aging is an inevitable biological process intricately linked to age-related diseases, including cardiovascular diseases, neurodegeneration, sarcopenia, and age-related macular degeneration. These ailments are often exacerbated by mitochondrial dysfunction, which plays a pivotal role in postmitotic cells. Curcumin, a natural compound, is explored for its anti-aging potential. This study explores the influence of curcumin on the postmitotic cellular lifespan (PoMiCL) of yeast during chronological aging, examining its potential implications for age-related diseases. Our findings reveal that curcumin significantly extends the lifespan of postmitotic wildtype yeast cells, with maximal effects observed at lower concentrations, displaying a hormetic response. Importantly, curcumin mitigates accelerated aging in cells afflicted by mitochondrial dysfunction. Intriguingly, the hormetic effect is absent under these conditions. Mechanistically, curcumin enhances ATP levels but induces oxidative stress and inhibits TORC1. These findings shed light on curcumin's potential as an anti-aging modulator and its relevance to age-related diseases, offering insights into novel therapeutic approaches for healthy aging while highlighting the context-dependent nature of its effects.
The aim of this research was to investigate the effect of curcuma dispersion bead milling on particle size evolution over time. The study of 10 wt.% and 20 wt.% curcuma dispersions revealed that dispersions’ polydispersity was decreasing up to 180 min which was found to be the optimum milling time with the volume mean diameter (d4,3) of (11.47 ± 0.85) μm. This diameter was the most effective with respect to the curcuma powder coagulation process attributed to the effect of curcuma oils after the milling time of 180 min. The mechanochemically atomized curcuma was used as a potential source of curcuminoids. By differential scanning calorimetry (DSC), two endothermic peaks were observed and related to curcuma melting effects. Curcumin powder exhibited one broad melting peak at 176 °C. Obtained data indicated that effective mechanochemical treatment makes curcuma powder a highly beneficial supplement applicable in food matrices of the human diet.
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Nowadays, polyherbal formulations are in demand for managing and treating many diseases owing to their less side effects. Thus, qualitative and quantitative standardization of these herbal formulations as per WHO and ICH guidelines is essential to ensure the quality and efficacy of the formulations. The present study involves the development of a simple and precise UV/Visible spectrophotometric method for simultaneous estimation of curcumin and ascorbic acid in the polyherbal antidiabetic formulation at their respective λ max 422 nm and 266 nm. The method obeys Beer's law in the concentration range of 2 to 10 μg/mL for both curcumin and ascorbic acid with a correlation coefficient of 0.9992 and 0.999, respectively. The limits of detection (LOD) and quantitation (LOQ) were found to be 0.225 μg/mL and 0.675 μg/mL for curcumin and 0.12 μg/mL and 0.36 μg/mL for ascorbic acid, respectively. The obtained results demonstrated that the proposed method is simple, sensitive, and cost-effective and can conveniently be employed for the routine analysis of any polyherbal formulations containing curcumin (Curcuma) and ascorbic acid (Amla). The method was validated as per ICH Q2R1 guidelines.
Conference Paper
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Oxidation of MXene.
The development of biodegradable films is an alternative to the use of environmentally unfriendly packaging. For that, several natural polymers can be used, such as starch, which has good characteristics like inherent biocompatibility, biodegradability, and easy availability. The functional performance of starch-based biodegradable materials can be extended or improved by adding antioxidant agents, as well as by using novel preparation techniques. The addition of natural antioxidants to the starch-based films can further contribute to the development of functional films. The objective of the present work was to develop starch-based active films added with hibiscus and turmeric extracts. Important properties of the filmogenic hydrogels and the films prepared by casting such as absorption and solubility in water and oxygen permeability rate were determined. Oxidative degradation can affect the inherent color, flavor, and microbial stability of a variety of foods, then the oxygen transfer rate (OTR) was also determined. The information learnt from this study will be of value for further developments employing natural polymers or biocomposites being used as primary packaging for foods. Present tendency is to create active or smart packaging materials and starch-based materials that will play a significant role from now on.
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Human epidemiological and laboratory animal model studies have suggested that nonsteroidal antiinflammatory drugs reduce the risk of development of colon cancer and that the inhibition of colon carcinogenesis is mediated through the alteration in cyclooxygenase metabolism of arachidonic acid. Curcumin, which is a naturally occurring compound, is present in turmeric, possesses both antiinflammatory and antioxidant properties, and has been tested for its chemopreventive properties in skin and forestomach carcinogenesis. The present study was designed to investigate the chemopreventive action of dietary curcumin on azoxymethane-induced colon carcinogenesis and also the modulating effect of this agent on the colonic mucosal and tumor phospholipase A2, phospholipase C gamma 1, lipoxygenase, and cyclooxygenase activities in male F344 rats. At 5 weeks of age, groups of animals were fed the control (modified AIN-76A) diet or a diet containing 2000 ppm of curcumin. At 7 weeks of age, all animals, except those in the vehicle (normal saline)-treated groups, were given two weekly s.c. injections of azoxymethane at a dose rate of 15 mg/kg body weight. All groups were continued on their respective dietary regimen until the termination of the experiment at 52 weeks after the carcinogen treatment. Colonic tumors were evaluated histopathologically. Colonic mucosa and tumors were analyzed for phospholipase A2, phospholipase C gamma 1, ex vivo prostaglandin (PG) E2, cyclooxygenase, and lipoxygenase activities. The results indicate that dietary administration of curcumin significantly inhibited incidence of colon adenocarcinomas (P < 0.004) and the multiplicity of invasive (P < 0.015), noninvasive (P < 0.01), and total (invasive plus noninvasive) adenocarcinomas (P < 0.001). Dietary curcumin also significantly suppressed the colon tumor volume by > 57% compared to the control diet. Animals fed the curcumin diet showed decreased activities of colonic mucosal and tumor phospholipase A2 (50%) and phospholipase C gamma 1 (40%) and levels of PGE2 (> 38%). The formation of prostaglandins such as PGE2, PGF2 alpha, PGD2, 6-keto PGF1 alpha, and thromboxane B2 through the cyclooxygenase system and production of 5(S)-, 8(S)-, 12(S)-, and 15(S)-hydroxyeicosatetraenoic acids via the lipoxygenase pathway from arachidonic acid were reduced in colonic mucosa and tumors of animals fed the curcumin diet as compared to control diet. Although the precise mechanism by which curcumin inhibits colon tumorigenesis remains to be elucidated, it is likely that the chemopreventive action, at least in part, may be related to the modulation of arachidonic acid metabolism.
We evaluated growth, yield and quality of turmeric (Curcuma longa L.) cultivated in pots with dark-red soil (pH 5.2), gray soil (pH 7.4) and red soil (pH 4.4) in Okinawa, Japan. The soils were collected from the 50-cm deep layer of the fields. We did not use any chemicals or organic fertilizers. Turmeric cultivated on dark-red soil had the highest plant height, root biomass and shoot biomass as compared with that cultivated on other soil types. Turmeric on dark-red soil had the highest yield with favorable color of the deep yellow and high curcumin content (0.20%). Protein content of turmeric in dark-red soil was 5.2%, which was around 40% higher than that in other soil types. Turmeric cultivated on dark-red and gray soils had a fat content 71% higher than that in red soil. The content of Ca, K and Mg was the highest when turmeric was cultivated on gray soil, and Fe was the highest when cultivated on dark-red soil. To gain a high yield and high contents of curcumin, fat, protein and Fe, we should cultivate turmeric in dark-red soil in Okinawa. We could not recognize the specific soil factor (s) required for high yielding and high quality of turmeric; however, it seems that a proper combination of soil factors, nutrients and/or pH level may be necessary to gain a high yield and high quality.
The genus Curcuma (family Zingiberaceae) comprising over 80 species of rhizomatous herbs, is endowed with widespread adaptation from sea level to altitude as high as 2000 m in the Western Ghats and Himalayas. Having originated in the Indo-Malayan region, the genus is widely distributed in the tropics of Asia to Africa and Australia. Curcuma species exhibit inter-and intra-specific variation for the biologically active principles coupled with morpho-logical variation with respect to the above-ground vegetative and floral characters as well as the below-ground rhizome features besides for curcumin, oleoresin and essential oil. Curcuma is gaining importance world over as a potential source of new drug(s) to combat a variety of ailments as the species contain molecules credited with anti-inflammatory, hypocholestraemic, choleratic, antimicrobial, insect repellent, antirheumatic, antifibrotic, antivenomous, antiviral, antidiabetic, antihepatotoxic as well as anticancerous properties. Turmeric oil is also used in aromatherapy and in the perfume industry. Though the traditional Indian Ayurvedic system of medicine and Chinese medicine long ago recognized the medicinal property of turmeric in its crude form, the last few decades have witnessed extensive research interests in the bio-logical activity and pharmacological actions of Curcuma, especially the cultivated species. Tur-meric powder obtained from rhizomes of Curcuma longa or related species is extensively used as a spice, food preservative and colouring material, in religious applications as well as a household remedy for bilary and hepatic disorders, anorexia, diabetic wounds, rheumatism and sinusitis in India, China and South-East Asia and in folk medicine. Cucuminoids, the bio-logically active principles from Curcuma, promise a potential role in the control of rheuma-tism, carcinogenesis and oxidative stress-related pathogenesis. Curcuma longa L. syn. Curcuma domestica Val., common turmeric, is the most economically valuable member of the genus having over 150,000 hectares under its cultivation in India. In addition to Curcuma longa, the other economically important species of the genus are C. aromatica, used in medi-cine and toiletry articles, C. kwangsiensis, C. ochrorhiza, C. pierreana, C. zedoaria, C. caesia etc. used in folk medicines of the South-East Asian nations; C. alismatifolia, C. roscoeana etc. with floricultural importance; Curcuma amada used as medicine, and in a variety of culinary preparations, pickles and salads, and C. zedoaria, C. malabarica, C. pseudomontana, C. montana, C. decipiens, C. angustifolia, C. rubescens, C. haritha, C. caulina etc. all used in arrowroot manufacturing. Crop improvement work has been attempted mainly in C. longa and to a little extent in C. amada. At present there are about 20 improved varieties of C. longa in India and one in C. amada, evolved through germplasm/clonal selection, mutation breeding or open-pollinated progeny (true turmeric seedlings) selection. Though work on morphol-ogical characterization of Curcuma species has been attempted, its molecular characterization is in a nascent stage except for some genetic fidelity studies of micropropagated plants and isozyme-based characterization. The genus has also been examined from the biochemical pro-filing and anatomical characterization angle. This article is intended to provide an overview of biological diversity in the genus Curcuma from a utilitarian and bio-prospection viewpoint.
The effect of curcumin administration in reducing the serum levels of cholesterol and lipid peroxides was studied in ten healthy human volunteers, receiving 500 mg of curcumin per day for 7 days. A significant decrease in the level of serum lipid peroxides (33%), increase in HDL Cholesterol (29%), and a decrease in total serum cholesterol (11.63%) were noted. As curcumin reduced serum lipid peroxides and serum cholesterol, the study of curcumin as a chemopreventive substance against arterial diseases is suggested.
After oral administration of 400 mg curcumin to rats, about 60% of the dose was absorbed. No curcumin was detectable in urine. The urinary excretion of conjugated glucuronides and sulfates significantly increased. No curcumin was present in heart blood. Only traces (less than 5 microgram/ml) in portal blood and negligible quantities in liver and kidney (< 20 micrograms/tissue) were observed from 15 min upto 24 h after administration of curcumin. At the end of 24 h the concentration of curcumin remaining in the lower part of the gut namely caecum and large intestine amounted to 38% of the quantity administered.
Curcumin, the natural antioxidant from turmeric, an Indian spice, and its derivatives have significant abilities to protect plasmid pBR322 DNA against single-strand breaks induced by singlet oxygen (1O2), a reactive oxygen species with potential genotoxic/mutagenic properties. 1O2 was generated at 37 degrees C in an aqueous buffer system by the thermal dissociation of the endoperoxide of 3,3'-(1,4-naphthylene)dipropionate (NDPO2). Among the compounds tested, curcumin was the most effective inhibitor of DNA damage followed by desmethoxycurcumin, bisdesmethoxycurcumin and other derivatives. The observed antioxidant activity was both time- and concentration-dependent. The protective ability of curcumin was higher than that of the well-known biological antioxidants lipoate, alpha-tocopherol and beta-carotene. However, the highest protective ability with saturating concentrations of curcumin did not exceed 50%. The ability of curcumin and its derivatives to protect DNA against 1O2 seems to be related to their structures and may at least partly explain the therapeutic and other beneficial effects of these compounds including anticarcinogenic and antimutagenic properties.
Earlier studies showed that curcumin is a potent inhibitor iron-catalysed lipid peroxidation. Demethoxycurcumin, bisdemethoxycurcumin and acetylcurcumin were tested for their ability to inhibit iron-stimulated lipid peroxidation in rat brain homogenate and rat liver microsomes. Comparison of the results with curcumin showed that all compounds are equally active, and more potent than alpha-tocopherol. These results showed that the methoxy and phenolic groups contribute little to the activity. Spectral studies showed that all compounds could interact with iron. Thus, the inhibition of iron-catalysed lipid peroxidation by curcuminoids may involve chelation of iron.
Curcumin (diferuloylmethane), a yellow pigment that is obtained from the rhizomes of Curcuma longa Linn., is a major component of turmeric and is commonly used as a spice and food-coloring agent. The inhibitory effects of feeding commercial grade curcumin (77% curcumin, 17% demethoxycurcumin, and 3% bisdemethoxycurcumin) in AIN 76A diet on carcinogen-induced tumorigenesis in the forestomach, duodenum, and colon of mice were evaluated. Administration p.o. of commercial grade curcumin in the diet inhibited benzo(a)pyrene-induced forestomach tumorigenesis in A/J mice, N-ethyl-N'-nitro-N-nitrosoguanidine-induced duodenal tumorigenesis in C57BL/6 mice, and azoxymethane (AOM)-induced colon tumorigenesis in CF-1 mice. Dietary commercial grade curcumin was given to mice at: (a) 2 weeks before, during, and for 1 week after carcinogen administration (during the initiation period); (b) 1 week after carcinogen treatment until the end of the experiment (during the postinitiation period); or (c) during both the initiation and postinitiation periods. Feeding 0.5-2.0% commercial grade curcumin in the diet decreased the number of benzo(a)pyrene-induced forestomach tumors per mouse by 51-53% when administered during the initiation period and 47-67% when administered during the postinitiation period. Feeding 0.5-2.0% commercial grade curcumin in the diet decreased the number of N-ethyl-N'-nitro-N-nitrosoguanidine-induced duodenal tumors per mouse by 47-77% when administered during the postinitiation period. Administration of 0.5-4.0% commercial grade curcumin in the diet both during the initiation and postinitation periods decreased the number of AOM-induced colon tumors per mouse by 51-62%. Administration of 2% commercial grade curcumin in the diet inhibited the number of AOM-induced colon tumors per mouse by 66% when fed during the initiation period and 25% when fed during the postinitiation period. The ability of commercial grade curcumin to inhibit AOM-induced colon tumorigenesis is comparable to that of pure curcumin (purity greater than 98%). Administration of pure or commercial grade curcumin in the diet to AOM-treated mice resulted in development of colon tumors which were generally smaller in number and size as compared to the control group of AOM-treated mice. These results indicate that not only did curcumin inhibit the number of tumors per mouse and the percentage of mice with tumors but it also reduced tumor size. Histopathological examination of the tumors showed that dietary curcumin inhibited the number of papillomas and squamous cell carcinomas of the forestomach as well as the number of adenomas and adenocarcinomas of the duodenum and colon.