Trace elements in Malaysian medicinal plants

Jointly published by Elsevier Science S. A., Lausanne and Akad#miai Kiad6, Budapest TRACE ELEMENTS

Journal of Radioanalytical and Nuclear Chemistry, Articles, Vol. 195,No. 1 (1995) 173-183

IN MALAYSIAN

MEDICINAL

PLANTS

A. AB.MAJID, S. SARMANI,N.I. YUSOFF*, Y.K. WEI, F.

Department of Nuclear Science, UniversitiKebangsaan Malaysia, 43600 Bangi, Selangor ,Malaysia. * Department of Chemistry, UniversitiKebangsacmMalaysia, 43600 Bangi, Selangor, MalayMa.

Elemental content of twenty medicinal plants used as tonic and for treatment of diabetes and sinusitis were determined by INAA and XRF. Elemental determination was carried out in the raw samples, residues after boiling and the water soluble fractions. Samples were irradiated in TRIGA IvlklI reactor and counted usm8 I-IPOe detector coupled to Personal Computer Analyzer (PCA) syste~n.Bowen's Kale, /fiBS Pine Needles, NBS Citrus Leaves SRM were analysed to check the accuracy of the techniques used. Twenty elements were determined by both NAA and XRF. Arsenic was only detected in Labisia pothoina and Dracontomelon dao with a concentrations of 0.40 mg/kg and 0.60 mg/kg respectively. Antimony was found in eleven samples with a concentration of < 0.20 mg/kg. AI, Br., Ca, C1, K, Mn, Na and Rb were detected in all samples whereas big and Zn were present in all samples exceptCinnamomum sp. Highest enneentration of Br ( 190 mg/kg), Cl ( 11805 mg/kg), Co (0.50 mg&g), Fe (1642 mg/kg), K (36788 mg/kg), Mn (325 mg/kg), Ha (126 mg/kg), Rb (197 mg/kg), Sc (0.18 mg/kg) and Zn (3551 mg/kg) were observed in the tuber ofLasia aculeata. Less than 70 % and 50 % of the elementscontained in Callicarpa longifolia and Eurycoma longifolia were obtained respectively from water by boiling.

Traditional medicine is an integral part o f Malaysian culture and has been practised by various ethnic groups long before the introduction o f m o d e m medical system into the country. In Malaysia there are about 1,200 species o f higher plants which have been reported to have medicinal properties and are used either singly or in combination to treat various diseases and ailments 1. Medicinal plant is defined as a plant which has been proven or claimed or thought to have medicinal remedies. In this paper elemental content o f twenty medicinal plants which are used as tonic and for diabetes and sinusitis treatment were determined by instrumental neutron activation and x-ray fluorescence techniques. Knowledge o f the elemental content in medicinal plants is very important because some o f these elements are closely related to human health 2. Elemental contents in several medicinal plants have been reported 3'4's. Although the direct link between elemental content and its curative capability has yet to be established, such

0236-5731/95/US$ 9.50 Copyright 9 1995 Akad#miai Kiad6, Budapest All rights reserved

A. AB. MAJIDet al.: TRACEELEMENTSIN MALAYSIANMEDICINALPLANTS study is vital to understand the pharmacological properties of medicinal plants. As far as Malaysia is concerned this kind of study is essential because traditional medicine i~ still being practised either as an alternative medicine or supplement to modern medicine even among our present modem society. The presence of toxic elements such as arsenic, mercury, antimony, selenium and zinc in our local sea food samples has been reported 6 but mention has ever been made regarding medicinal plants. With increasing

industrialization and environmental

pollution, the contents of these elements need to be evaluated apart from the normal intake of these dements via soil, fertilizer or herbicide. The aim of this study is to determine the content level of trace eleme~ in Malaysian medicinal plants to establish their safety to the users of tmdifonal medicine. Experimmtal Somp/e/ml~aratkm: Twenty medicinal plants7 which are used as tonic and for treatment of diab~es and sinusitis were either collected from the field or bought from traditional medicine Inclitiom~. Cleaned sampleswere freeze-dried and blended to produce homogenized powder. sampleswere kept in plastic bottles for further analysis. Callicarpa longifolia

The ~ and ~ / r

samples were boiled with triple distilled water. The boiled water

~ n ~ s were freeze dried and the residues were analysed for their elemental contents. Pellets of the medicinal plants samples were prepared by pressing about 1 g of powdered rumplestogeth~ with cdlukne and boric acid at a pressure of 15 - 20 tonnes in AI can for XRF

Standards were prepared from spectroscopy grade chemical standard solutions. Standard reference ~

;

Bowen's Kale (Reading Uni.), Citrus Leaves (NBS) and Pine Needles

(NBS) were analysed to che~ the accuracy of the tedu6ques used.

Sample irr~!i'~lion: About 100 mg of each medicinal plant powdered samples, SRMs and stmldm~ were packed in heat resistant polyethylene vials and sent for irradiation in TRIGA MidI Nm:learEnergy Unit research reactor for 30 seconds, 2 rainutes and 6 hours at a neutron tkm of2.2 x 10t2 ncm'2s'~depemfi~ on tl~ elements to be determined. of e/emend. In INAA tedmiquc the short counting time for gamma ray act~ties of ~ ~ leeVmd ~

samples were caniad out at the PUSPATI Nuclear Energy Unit using a high r

OfORTEC lq~C~ ~ w i t h

d~icmcy of 20 dy~"[he de~_~,~__orwas connected to ORTEC 472A Spectroscopy

A~pll~aer a~! Nadear Dala 1~1366Mtdlidmnnd Analyzer ~ P~k ~

IT4

a resolution of 1.8 keV at 1332

aad ~

at 0.5 keY per channel.

were eanied out by dedieated PDPI 1 combus compnter

A. AB. MAJID et al.: TRACEELEMENTSIN MALAYSIANMEDICINALPLANTS connected to the system. Whereas the long counting time for gamma ray activities were measured in Universiti Kebangsaan Malaysia using HPGe Coaxial detector with a resolution of 1.8 keV at 1332 keV coupled to Nucleus PCA system. Spectrum analysis was carried out using Quantum Technology GDR version 4.5. In the x-ray fluorescence technique, pellets of the medicinal plants powder were analysed using PHILIPS PW 1480 x-ray fluorescence spectrometer9 The system consisting of x-ray tube (maximum voltage 100 kv, maximum current 75 mA), analysing crystals (Ge, LiF 220, PE-C) and proportional or scintillation counter. All samples were counted for 180 seconds and calibration curve technique was employed to quantify the elemental content in the samples.

Results and Discussion

The result of elemental analysis of Bowen's Kale, Citrus Leaves and Pine Needles SRMs is presented in Table 1. In general the accuracy of both INAA and XRF techniques used in this study was found to be satisfactory. For dements such as As, Ca, Fe, and K the accuracy of 70 % was observed. Traditional medicines, generally include various readily available natural resources such as plants, animals or minerals. It. our study, medicinal plants (mostly root) which are used as tonic (Mussaenda sp., Labisia pothoina, Callicarpa longifolia, Eurycoma longifolia and Smilar sp.) and for diabetes and sinusitis treatment were either collected from their wild habitat in Sri Menanti and Endau Rompin forests or bought from traditional medicine practitioners. Patients or users of the traditional medicine normally drink the water boiled with prescribed selected medicinal plants or in the powder form of the plants. A total of twenty dements i.e. AI, As, Ba, Br, Ca, Ce, CI, Co, Cs,. Cr, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc and Zn were determined in the powdered medicinal plant samples by both INAA and XRF. Elemental content of the each sample is shown in Table 2, whereas the range and mean concentration of dements determined in the samples are given in Table 3. This result clearly showed that the elemental content in the samples varied depending on the species of the medicinal plants. The high concentration of Ca, Fe, K and Mg in our samples is expected due to their involvement in the cell wall formation of the plants. The same situation has been reported in other medicinal tropical woods 4. Arsenic was determined in only two samples i.e. Labisiapothoina and Dracontomelon dao with a concentration of 0.40 mg/kg and 0.60 mg/kg respectively. Antimony was found in 175

A. AB. MAJID et al.: TRACE ELEMENTS IN MALAYSIAN MEDICINAL PLANTS

Table 1 Comparison of the accuracy analysis of Bowen's Kale, Citrus Leaves and Pine Needles Standard Reference Materials,(mg/kg).

Bowen's Kale

Eiemen

Pine Needles

Citrus Leaves

Certified

Experimental

Certified

Experimental

Certified

Experimental

value I~

value

value to

value

value t~

Value

t

1NAA

XRF

XRF

INAA

XRF

A1

(39.9)*

n.d*

25.8

92

n.d

124

545

n.d

508

As

(0.131)

n.d

0.14

3.1

2.9

2.7

0.21

0.15

0.28

Br

24.9

18.3

n.d

(8.2)

8.2

n.d

(9)

9,

n.d

Ca

41060

34216

40012

31500

34131

32001

4100

1633

4016

(0.4)

n.d

0.4

Ce

(0.210)

n.d

0.160

(0.28)

n.d

0.25

CI

3560

1560

n.d

(414)

n.d

n.d

--

Co

0.0632

0.72

n.d

(0.02)

n.d

n.d

(0.1)

0.1

n.d

2.3

n.d

n.d

3.5

Cr

(0.369)

. . . .

0.8

0.7

n.d

2.6

Cs

0.0763

. . . .

(0.098)

0.070

n.d

..

Cu

4.89

n.d

4.58

16.5

n.d

15.81

3.0

Be

119.3

120.8

106.9

90

114

100

200

112

195

K

24370

21007

22487

18200

16646

18984

3700

3860

3267

La

0,0864

n.d

0.11

(0.19)

n.d

0.15

(0.2)

n.d

0.2

(14.82)

15.00

14.81

23

n.d

22

675

n.d

682 n.d

Na

2366

2104

n.d

160

n.d

n.d

--

36.77

Ni

(0.895)

n.d

0.59

0.6

n.d

0.58

(3.5)

n.d

3.0

P

4480

n.d

4536

1300

n.d

1275

1200

n.d

1201

Rb

53.4

n.d

49.95

4.84

4.64

1.54

11.7

6.6

12.7

Sb

(0.0685)

0.0750

(0.04)

0.04

n.d

(0.02)

0.02

n.d

Se

(0.0095)

n.d

0.008

(0.01)

0.01

0.01

(0.03)

0.04

0.04

Sr

(75.7)

n.d

93.89

100

n.d

94

4.8

n.d

3.2

Zn

32.29

29.98

n.d

29

n.d

n.d

.

* ( ) indicating not certified value; n.d not detected; --

176

INAA

not determined

l n.d

.

.

.

.

.

A. AB. MAJID et al.: TRACE ELEMENTS IN MALAYSIAN MEDICINAL PLANTS

Table 2 Elemental Content of the Powdered Medicinal Plants (mg/kg) Element

Commersonia

Rafflesia sp

platyphylla

Tabernaemontan

Cinnamomun

Gelonium sp

a sp

sp

AI

365 • 47

902 4- 87

700 4- 33

486 4- 62

807 • 62

As

n.d

n.d

n.d

n.d

n.d

Ba

25.04- 1.0

n,d

n.d

4 2 . 0 • !.2

351.3 4- 11.1

Br

2.01 + 0 . 2 0

0.824-0.20

7.154-0.60

2.284-0.30

3.79 4- 0.50

Ca

36454-495

7604-85

99034-717

16394-200

119054-1065

Ce

0.94 4- 0.50

0.32 4-0.01

n.d

n.d

3.704-0.10

CI

6294-16

10024-50

7764-56

364 4- 54

8974-4-3

Co

0.06 4-0.02

0.104-0.01

0.234-0.~

0.084-0.10

0.46 4- 0.10

Cs

0.234-0.05

0.33~0.01

0.884-0.~

2.174-0.10

2.824-0.I0

Cr

n.d

0.43•

2.254-0.20

n,d

3.32•

Fe

944-33

1174-11

1474-36

1404-3

1164-

K

34824-61

363104-1193

30604-124

33134-11

6703 ~ 2

La

0.214-0.05

0.134-0.02

0.114-0.10

Mg

15724-186

7244-21

18324-150

bin

22.64-3.4

17.24-3.7

~.54-0.5

88.24-1.2

195.44-7.3

Na

55.04-2.0

40.24-1.3

36.74-2.0

81.24-1.3

13.64-1.2

0.144-0.06 n.d

I . ~ 4-0.10 9504-68

Rb

30.54-2.0

233.64-3.0

50.94-1.6

~.14-1.9

53.54-I.I

Sb

n.d

0.0234-0.002

0.1044-0.001

0.1724-0.004

0.054-0.01

Sc

0.20 4-0.02

0.04 4-0.02

0 . ~ 4- 0.02

0.02 4- 0.02

0.04 4-0.02

Zn

11.64-3.9

13.94-0.2

110.94-9.4

n.d

35.1•

177

A. AB. MAJID et al.: TRACE ELEMENTS IN MALAYSIAN MEDICINAL PLANTS

Table 2

continued Element

Rubus sp

Mussaenda sp

Labisia pothoina

Callicarpa

Eurycoma

AI

446• 115

1092 • 113

1377 4- 77

longifolia

longifolia

283 4- 69

277 4- 46

As

n.d

n.d

0.40 • 0.04

n.d

n.d

Ba

47.24-7.8

Br

3,054-0.20

112.4 4- 1.1

59.5 + 6.5

26.84-3.9

n.d

2.674-0.03

1.72 4- 0.08

3.804-0.20

6.03 4- 0.50

Ca

3558 4- 105

4684 • 104

27074 4- 1754

33164-49

3081 4- 105

Ce

1.284-0.30

20.44•

0.83 4- 0.04

2.86 4- 0.30

1.46 4- 0.40

C1

10924- 17

264-21

309 4- 25

1194-18

1479 4- 47

Co

0.10•

0.554-0.55

0.564-0.01

0.124-0.02

n.d

Cs

1.50 4- 0.30

0.474-0.04

1.654-0.07

n.d

0.08 • 0.04

Cr

2.06 4- 0.40

4.754-0.83

1.464-0.15

1.64 4- 1.60

2.564-0.~

~Fe

1274-3

1654-3

3854- 10

784-24

574-9

K

4042 4- 6

3731 4- 421

14891 4- 481

34684- 13

2914 • 48

La

0.75~0A0

3.244-0.03

0,294-0.13

1,564-0.10

0.03•

1471 4- 294

640 4- 84

1333 4- 52

768 4- 55

64 4- 17

141.04-3.0

210.4 4- 5.0

327.5•

76,74-0.4

26.5~0.6

69.94-4.2

19.94-2.7

109.84-1.2

121.84- 1.8

135.4•

Rb

66.64-20.4

36.24-3.8

238.9•

59.84-3.1

Sb

0 . 0 8 4- 0.01

0.03 4- 0.03

0.06•

0.144-0.10

10.024-0.01

Se

0.034-0.02

0.184-0.02

0.09•

0.024-0.02

0.024-0.02

Zn

138.04-27.9

42.6•

70.24-1.1

20.64-5.0

15.44-5.4

Mg Mn Na

178

13.64-1.3

A./LB. MAJID et al.: TRACE ELEMENTS IN MALAYSIAN MEDICINAL PLANTS

Table 2

continued Element

Smilax sp

Spatholobus sp

Lesia aculeata

Pithecellobiu

Canarium sp

: mfiringa AI

975 4- 177

230 • 19

1632 • 143

1590 4- 146

824-39

As

n.d

n.d

n.d

n.d

n.d

Ba

n.d

n.d

n.d

n.d

n.d

Br

1.644-0.12

2.384-0.05

189.62 •

10.57 + 2.02

0.82•

Ca

941 4- 109

4530 4- 503

9273•

11795 4- 465

2856 4- 79

Ce

0.25•

0.69 4- 0.69

n.d

n.d

0.114-0.01

C1

958 4- 36

11914-11

11805+4

1~14-27

429 a- 39

Co

n.d

0.064-0.06

0.504-0.01

0.07 4- 0.02

n.d

Cs

0.22•

1.47 • 0.06

0.764-0.07

1.06 4- 0.04

0.244-0.~

Cr

0.44 4- 0.07

0.64 4- 0.64

3.944-0.03

3.37 4- 0.29

1.284-0.09

Fe

127 • 9

914-12

1~24-86

1674-26

n.d

K

4096 4- 121

42664-165

36788•

13~4-79

7274-186

La

0.154-0.07

0.144-0.06

0.51•

0.144-0.02

n.d

Mg

315•

535•

599•

577 4-42

Mn

6.4•

37.9•

325.24,12.3

63.44-0.3

Na

46.2•

29.94-3.6

125.9•

40.24-5.3

18.2•

Rb

12.24,1.4

48.54-4.1

196.6•

83.84-1.0

0.3 4-0.3

Sb

n.d

n.d

n.d

n.d

n.d

Sc

0.044-0.02

n.d

0.184-0.02

0.074-0.02

n.d

Zn

4.8•

20.8•

3551.0 • 91.0

73.0 4- 1.0

16.0•

0.52

.307• 4.74-0.9

179

A. AB. MAJID e,,tal.: TRACE ELEMENTS IN MALAYSIAN MEDICINAL PLANTS

Table 2 continued Element

Phyllanthus sp

Lauraceae

Fagraea

Dracontomelon Mimusops

firinga

racemosa

dao

elengi

AI

113 • 19

751 • 35

2951 • 62

1333 • 156

1087 • 66

As

n.d

n.d

n.d

0.60 • 0.08

n.d

Ba

n.d

n.d

n.d

23.6 4- 2.10

32.6 • 1.70

1.04•

2.59•

2.30 4- 0 . 2 1

1.25•

1.98• 7593 4-434

! Br Ca

1333 • 1

1510 • 165

205174-4144

3~75•

Ce

0.66 • 0.64

n.d

1.39 • 0.38

1.08 • 0.26

4.43 4-0.50

C1

~04-51

545 4- 23

839 4- 33

530 4- 12

6~• 0.12 •

Co

n.d

n.d

0.114-0.05

0.124-0.02

Cs

1.63 • 0.03

0.674-0.05

1.244-0.06

1.824-0.12

1.49•

Cr

0.71 • 0.08

2.944-0.45

2.324-0.54

1.87 • 0.23

2.61•

Fe

194-3

1104-23

530 4- 38

183•

189 4- 66

K

727 • 60

3148+ 113

7146• 164

6665 • 292

4144 4-58

La

0.04•

n.d

0.14•

0.38•

0.93 •

Mg

n.d

217 •

1449•

10894-43

10484-138

Mn

99.84-1.1

30.8•

94.2•

32.3•

167.5•

Na

14.04-1.9

34.2•

162.4•

74.0•

48.6•

Rb

20.1•

119.14-4.1

154.44-4.8

128.9•

52.84-1.7

Sb

0.034-0.01

n.d

n.d

n.d

0.07 + 0.02

Sc

n.d

0.04 4- 0.02

0.184-0.01

0.094-0.01

0.11 + 0.03

Zn

39.04-3.0

12.0•

19.04-1.0

301.0 + 2.0

18.04-4.0

eleven samples with a concentration o f < 0.20 mg/kg. These values well below a Malaysia F o o d Act 19838 permissible limit which is 1 mg/kg. AI, Br, Ca, CI, K, Mn, Na and Rb were determined in all samples whereas Mg and Zn were present in all samples except Cinnamomum sp. Highest concentration o f Br (189.62 mg/kg), CI (11805 mg/kg), Co (0.56 mg/kg), Fe (1642 mg/kg), K (36788 mg/kg), Mn (327.5 mg/kg), N a (125.9 mg/kg), Rb (196.6 mg/kg), Sc (0.18 m g / k g ) and Zn ( 3 5 5 1 m g / k g ) were determined in a tuber o f L a s i a

aculeata. In general the

concentration range o f the elements determined in our samples is comparable with elemental content in tea leaves 9 and various medicinal plants 3,4,s.

180

A. AB. MAJID et al.: TRACE ELEMENTS IN MALAYSIAN MEDICINAL PLANTS

Table 3 Summary of the range and mean concentration of the elemants determined in powdered medicinal plant samples (mg/kg).

Elemant

Range

Mean

AI

82 - 2951

874

As

0"- 0.60

0.05

Ba

0 - 23.6

36.3

Br

0.82 - 189.62

12.38

Ca

760 - 30675

8029

Ce

0 - 20.44

2.02

CI

2 6 - 11805

1318

Co

0 - 0.56

0.16

Cs

0 - 2.82

1.04

Cr

0 - 4.75

1.93

Fe

0 - 1642

224

K

727 - 36788

7548

La

0 - 3.24

0.50

Mg

0 - 1832

774

Mn

4.7 - 327.5

100.6

Na

13.6- 162.4

63.9

Rb

0.3 - 238.9

82.0

Sb

0 - 0.17

0.04

Se

0 - 0.20

0.07

Zn

0 - 3551

225

* = not detected/limit of detection

Callicarpa longifolia ( l o c a l n a m e Tampang'Besi) Tongkat Ali), b o t h w a t e r b o i l e d s a m p l e s w e r e a l s o % a n d 5 0 % & t h e e l e m e n t s c o n t a i n e d in Callicarpa

D u e t o t h e i r p o p u l a r i t y as a t o n i c d r i n k , and

Eurycoma longifolia ( l o c a l

name

analysed. T h e result s h o w e d less t h a n 7 0

longifolia

and

Eurycoma longifolia r a w

samples were taken up respectively into water by

boiling. N o t o x i c e l e m e n t w a s d e t e r m i n e d in t h e r e s i d u e o f t h e s a m p l e s . T h i s r e s u l t is s h o w e d in T a b l e 4.

181

A. AB. MAJID et al.: TRACE ELEMENTS IN MALAYSIAN MEDICINAL PLANTS

Table 4 Elemental content of the water boiled with Callicarpa longifolia and Eurycoma longifolia roots (mg/L).

Callicarpa longifolia Element

Eurycoma longifolia

in water

percentage

in water

percentage

AI

284-2

10

544- 1

19

Ca

644- 13

2

107 4- 20

4

Ce

0.21 4- 0.02

7

n.d

--

Co

0.07 4-0.03

58

n.d

--

Cs

n.d

--

0.04

50

Cr

n.d

0.144-0.04

6

Fe

124-2

16

28 + 3

49

K

2260 4- 18

65

1220 4- 21

42

La

0.03 4-0.01

2

0.02 4- 0.01

50

Mn

17.1 4- 1.2

22

5.5•

21

Na

69.4 4-0.5

57

31.0 ~-0.5

23

Rb

40.5 :L0.4

68

4.2+0.3

31

Sb

nd

--

n.d

--

Sc

rid

u

0.01

50

Zn

5.56 4- 0.16

27

0.23 4-0.02

2

Although the trend linking the elements o f the medicinal plants to its curative abilities could not be clearly determined, but this study showed that the toxic elements found in the samples were below the level allowed by the Malaysian Food Act 1983 and Food Regulations 1985.

Conclusions A total o f twenty elements have been determined in twenty medicinal plant root samples by I N A A and XRF. The concentration o f elements determined was varied depending on the species o f t h e plants. Although the trend linking the elements o f the medicinal plants to its curative abilities could not be clearly determined, this study showed that the toxic elements 9found in the samples were below the level allowed by the Malaysian F o o d Act 1983 and Food R e g u l a t i o n s 1985. With recent regulation imposed by the Ministry o f Health, Malaysia requiring all traditional medicine practitioners to register their products, w e hope our finding will be useful in setting the baseline o f elemental content in medicinal plants. 182

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