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Cancer Research and Clinical Oncology
Editorial Article
Open Access
Anti-Cancerous Compounds In Brassica
Anubhuti Sharma*
ICAR-Directorate of Rapeseed Mustard Research, Sewar, Bharatpur, Rajasthan, India
*Corresponding Author:
Anubhuti Sharma
ICAR-Directorate of Rapeseed Mustard Research,Sewar, Bharatpur, Rajasthan, India
Fax: 05644-260565
Tel: 7579269471, 9772429768
Email: [email protected]
Received on: February 8, 2017 | Accepted on: February 8, 2017 | Published on: February 27, 2017
Citation: Anubhuti Sharma. Anti-Cancerous Compounds In Brassica. Can Res and Clin Oncology 2017; 1(1): 1-2.
doi: 10.00000/crco.2017.101
Copyright: © 2017 Anubhuti Sharma. This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CCBY) (http://creativecommons.org/licenses/by/4.0/) which permits commercial use, including reproduction, adaptation, and distribution of the article provided the
original author and source are credited.
Published by Scientific Synergy Publishers
Editorial
Oilseed plants have received considerable attention due to the role of endogenous bioactive compounds in human nutrition.
Glucosinolates are one of the major secondary metabolite of oilseeds. These compounds are found in all Brassica vegetables,
seeds [cabbage, brussels, sprouts, radishes, broccoli, and cauliflower] and are responsible for the desirable pungent odor and
sharp flavor associated with these foodstuffs. Brassica seeds such as rapeseed and mustard are particularly rich in
glucosinolates while canola seeds have much lower total glucosinolate contents. While high levels of glucosinolates may be
desirable in the case of mustard seed destined for condiment use, the high levels of glucosinolates found in rapeseed meal have
restricted the use of this seed as a source of protein in compound feeds. Glucosinolates are also natural toxicants, being
associated with goiter and liver damage when consumed in large quantities. Till date nearly 200 Glucosinolates types have
been identified which are classified into three classes based on the structure of different amino acid precursors: aliphatic,
indole, and aromatic? The glucosinolates are sequestered within the subcellular compartments and remain as chemically
stable and biologically inactive compound. However tissue damage caused by pests, harvesting, food processing or chewing
initiates contact with the endogenous enzyme myrosinase, [thioglucoside glycohydrolase; EC 3.2.3.1]. This leads to rapid
hydrolysis of the glucosidic bond, releasing glucose and an unstable intermediate, which undergoes a spontaneous
rearrangement into several potentially toxic compounds. This whole process is dependent on the reaction conditions and the
presence of specifier proteins to form a complex variety of breakdown products.
To prevent constitutive production and potential damage
to the plant cells, myrosinase is stored separately from its
substrates in specialized cells called myrosin cells. The
hydrolysis products are produced upon attack by herbivores
or pathogens when damage to the plant tissue and disruption
of the cells causes myrosinase to come into contact with
glucosinolates. The levels of glucosinolates ingested depend on
various factors e.g. crop variety, agronomic factors, and both
storage and processing of the vegetables prior to consumption.
It has been noticed that mechanical damage such as cutting
and pre-harvest stress leads to the rapid hydrolysis and
degradation of glucosinolates, to increase the concentrations
of indole glucosinolates in cabbage. Glucosinolates undergo
enzymatic hydrolysis by the enzyme myrosinase after tissue
damage and yield a variety of biologically active products i.e.
Isothiocyanates,
Oxazolidine-2-thiones,
Nitriles
and
Thiocyanates. These products have a wide range of biological
Can Res and Clin Oncology 2017
activity including nutritional & antinutritional attributes and
effect on plant herbivores. The small sulfur-containing
isothiocyanates [ITCs] are the major research target in recent
years due to their anticancer and chemopreventive properties.
Most of the isothiocyanates, both natural and synthetic,
reduces activation of carcinogens and increase their
detoxification. Recent studies show that they exhibit antitumor activity by affecting multiple pathways including
apoptosis, MAPK signaling, oxidative stress, and cell cycle
progression. Sulforaphane is perhaps the most widely known
crucifer-derived cancer chemopreventive ITC.
Isothiocyanates [ITCs] have negative effects on the growth
of various fungal species. It has been also shown that following
exposure to ITC, fungal cells displayed biological stress with
over-expression of several genes involved mainly in cell
protection against oxidative damage. ITCs may also react via
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direct protein modification or indirectly by disruption of
redox homeostasis and increased thioloxidation. Once
isothiocyanates are ingested or formed in the lumen of the
gastrointestinal tract, they cross the gastrointestinal
epithelium and the capillary endothelium by passive diffusion.
They bind rapidly and reversibly to thiols of plasma protein
and cross the plasma membrane into cells of tissues. Inside
cells, isothiocyanates react with glutathione to form the
glutathione conjugate, which is expelled from cells by
transporter proteins and further metabolized to mercapturic
acids. These isothiocyanate can be measured in the urine and
are highly correlated with dietary intake of cruciferous
vegetables. Although numerous studies have shown ITCs to
interfere with the cell cycle progression of cancer cells, no
studies have to our knowledge targeted the effect of ITCs on
the plant cell cycle. Despite research efforts over the last
decades, our understanding of the progression and regulation
Can Res and Clin Oncology 2017
of the plant cell cycle remains limited. Whatever the final level
of glucosinolates in the prepared vegetable, the absorption,
metabolism and delivery of glucosinolate breakdown products
to target tissues depends, to a large extent, upon the residual
level of myrosinase activity. In the scenario of protective role
of brassica vegetables, it is utmost important to emphasize the
potential role of consuming a wide variety of brassica
vegetables in many different culinary forms and dietary
patterns. Presence of glucosinolate in brassica vegetables
influences both palatability and potentiality. However its level
can be manipulated by plant breeders. Both these issues [i.e.
palatability with potentiality and level] need to be considered
when breeding new varieties of brassica vegetables. Further
research is required to study the biological activities of the
glucosinolate products as anti-carcinogen in greater detail, so
that consumer’s benefits in terms of balance of benefits and
risks can be properly defined.
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