Investigation into the Authenticity
of Commercial Mace Spice Products Sold in a Local Market in India.
Reviewed: Swetha VP, Parvathy VA, Sheeja TE, Sasikumar B.
Authentication of Myristica fragrans Houtt. using
DNA barcoding. Food Control. 2017;73(B):1010-1015.
Keywords: Myristica fragrans, Myristica
malabarica, adulteration, DNA barcoding
The nutmeg tree (Myristica
fragrans, Myristicaceae) is the source of two spice products: nutmeg,
derived from the kernel, and mace, derived from the aril surrounding the seed. Nutmeg
and mace are commonly used to season potato dishes, processed meat products,
soups, sauces, and baked goods. Global nutmeg production is estimated to be
between 10,000 and 12,000 metric tons per year; annual mace production is
estimated at 1500 to 2000 metric tons.1
The Food and Agriculture Organization of the
United Nations (FAO) lists M. argentea, the source of 'Papuan' nutmegs from Irian Jaya and
Papua New Guinea, and M. malabarica, which yields the 'Bombay' nutmegs
from India as adulterants of M. fragrans
products.2 Bombay nutmeg has a yellow color, lacks the
nutmeg aroma, and is mainly used as a natural dye.
Using authenticated fresh leaf samples of M. fragrans and M. malabarica,
the authors of this study evaluated DNA barcoding as an authentication tool for
mace using the loci rbcL, matK, psbA-trnH, and ITS. Amplification success was
achieved in all samples using the rbcL, psbA-trnH and ITS gene regions; however, the
ITS locus generated mixed sequence data in most of the samples, and rbcL showed low species resolution, thus limiting their
usefulness as a barcode for distinguishing Myristica
species.
Finally, psbA-trnH
was found to be ideal for Myristica
species distinction, and was used to determine the authenticity of five
commercial samples sold as mace in different shops in Kozhikode, Kerala, India.
The psbA-trnH sequences of three of the
samples corresponded to M. malabarica,
while the other two were authentic M. fragrans
mace.
Comment: Besides its use as a spice, nutmeg and/or mace
is used medicinally for disorders of the gastrointestinal tract, such as
diarrhea, gastric spasms, intestinal catarrh, and flatulence. Adulteration of
nutmeg with materials derived from other Myristica
species is well known, but data on the extent of the problem are limited. DNA
sequencing of the psbA-trnH region
has provided suitable results for both the authentic fresh leaf material and
the dried ground commercial products, and can be used as an identification
method for fresh or dried crude raw material. According to Pandey et al.,
distinction of Myristica species is also
possible by chemical means.3 A comparison of ethanol extract
fingerprints of the seed, mace, and pericarp of M. fragrans,
M. malabarica, M. beddomei,
and Virola surinamensis (syn. M. fatua) using high-performance liquid chromatography with
quadrupole time-of-flight mass spectrometric detection (HPLC-qTOF-MS/MS)
demonstrated that the four species could be distinguished in this manner. While
the HPLC-qTOF instrument may not be in everyone’s budget, similar results may
be achieved using gas chromatography with a universal detector, e.g., GC-FID or
GC-MS.
References
1.
Nutmeg. Surabaya, Indonesia: Unispices Asia website. Available at: http://unispices.asia/knowledge-base/nutmeg.html. Accessed February 14, 2017.
2.
Nutmeg and
derivatives. Rome, Italy: Food and Agriculture Organization of the United
Nations. 1994. Available at: http://www.fao.org/docrep/019/v4084e/v4084e.pdf. Accessed February 14, 2017.
3. Pandey R, Mahar R, Hasanain M, et al. Rapid screening and quantitative determination of bioactive compounds from fruit extracts of Myristica species and their in vitro antiproliferative activity. Food Chem.
2016;211:483-493.
