Int. J. Life. Sci. Scienti. Res., 3(3):
1039-1046, May 2017
Effects of Temperature and Storage
Duration on Antioxidant Status in Coriandrum
sativum Linn.
RiaWilliam D’Souza*1, Dr. Vijaya Lobo2
*1Student,
Department of Botany, St. Xavier’s College, Mumbai, India
2Assistant Professor, Ph.D., Department of Botany, St. Xavier’s
College, Mumbai, India
*Address for correspondence: Ms. Ria William D’souza, Department
of Botany, St. Xavier’s College, Autonomous, Mumbai-400001, Maharashtra, India
ABSTRACT- Coriandrum sativum Linn. is a promising functional food which is not only known to
provide nutrition, but also medicinal benefits and is a potent source of
antioxidants. The study monitors effect of storage temperature (-2.2oC)
and duration (0, 3, 6, 9 days) on antioxidant status of the plant. All
parameters present in this study– Ascorbic acid, Tocopherol, Total phenols,
SOD, POX, CAT, content were studied by spectrophotometric assays. A number of
preservation methods have been designed to extent the shelf life of the food
product and to maintain their antioxidant potential. The aim of the present
study was to monitor changes in the above mentioned antioxidants during
refrigerated storage. The study hypothesizes that as the storage period
increases the level of enzymatic antioxidants increase with increase in degree
of damage whereas the non-enzymatic antioxidants decrease (except phenolic) and
concludes that the overall antioxidant status of the plant decreases
considerably during storage condition. During storage, these antioxidants
probably react with free radical, produced by aerial oxygen and are depleted,
decreasing their concentration, despite being stored at refrigerator
conditions.
Keywords: Coriandrum sativum Linn., Antioxidant activity, Phenolic content, storage,
temperature
INTRODUCTION- Coriander is an annual
herbaceous plant belonging to family Umbellifereae (Apiaceae). South Asia being
the world’s largest producers, it is a cosmopolitan plant. The green, young
coriander leaves (cilantro) and the aromatic coriander fruit or seeds are known
to find its uses in culinary as garnishes and spice respectively. Various parts
of this plant viz. seeds, leaves, flowers, fruits are known to possess
antioxidant, anticonvulsant, antidiabetic, anti-mutagenic, antimicrobial,
anthelminthic, antifungal, antibacterial, sedative hypnotic, diuretic,
stomachic, spasmodic, and carminative activities [1-5]. Coriander contains
essential oils, limpene, coriandrin, geraniol, citronellol, α-pinene,
flavonoids, catechin, gallic acid, vicenin, Linalool etc. which give it the
above assigned properties [2, 5-6]. Research literature
also suggests that coriander has been explored in-vivo for its various
biological activities such as prevention of oxidative damage, inhibition of
microbial growth, diabetes management, neurological disease benefits, pain
reduction etc [1].
Antioxidant activity of coriander- Coriander gets its antioxidant activity at the onus of bioactive
compounds viz. flavones, isoflavones, flavonoids, anthocyanin, coumarins,
lignins, catechin and isocatechins and is thus referred as store house for
bioactive compounds [5-6]. Further research also suggests that the chemical
compounds that coriander possess apart from above mentioned which attribute to
antioxidant properties are apigenin, ascorbic acid, β-carotene, caffeic
acid, camphene, γ-Terpinene, isoquercitin, myristic acid, myristicin, ρ-hydroxy-benzoic
acid, palmatic acid, protocatechenic acid, Terpinolene, trans-anethole [5].
Coriander leaves show stronger anti-oxidant activity than seeds. There is a
positive correlation between TPC and antioxidant effect, thus, screening of
phenolic content in coriander will indicate presence of compound with
antioxidant activity [2,5]. In etheric extracts from coriander carotenoid
fractions, β-carotenes were identified as principal antioxidant compounds
[2]. Studies also indicate that antioxidant activity of seed essential oils
higher than coriander leaves essential oil. Many explorations have been done on
activities using various extracts and various plant parts. Thus, making it a
functional food.
Postharvest losses in relation to quantity and quality of food are
major problems all over the world. Apart from appearance, texture, and flavors
and nutritive value of bioactive compounds, quality parameters including
storage duration and temperature also play a vital role to increase shelf-life
of product and consumer acceptability [3,5]. Postharvest storage conditions,
senescence etc. are known to have influence on antioxidant status and phenolic
content of the plant [3,4,7-8]. The prospective (aim) of the current study was
to monitorchanges in antioxidant levels in effect to storage duration and
temperature (-2.2oC). Current study focuses on analyzing three
enzymatic antioxidants, three non-enzymatic antioxidants and a biochemical at a
constant temperature which would allow us to interpret optimal storage duration
at that temperature for antioxidant retention and thus, enhancing consumer
acceptability.
MATERIAL AND METHODS- The research was carried out at St. Xavier’s college, Autonomous,
Mumbai in Department of Botany. The study was carried out between December,
2016 and February, 2017.
Procurement of samples-
Samples of Coriandrum
sativum Linn. were purchased from a local market at Parnaka Vasai (W). The
samples were identified using Flora’s from Blatter Herbarium, St. Xavier’s
College, Mumbai.
Storage experiment- Samples
were thoroughly washed under tap water dried and then cleaned for impurities.
Further, these were divided into four sufficiently equal amounts for preparing
various types of extracts for assays to be conducted. The 0 day sample was
extracted without giving any experimental conditions whereas the other samples
were wrapped in newspapers (a traditional house-hold practice) well labelled as
per the days and kept in refrigerator. The temperature was monitored each day
for 9 days using “Indoor Outdoor Thermometer with hygrometer clock” (mini-max
thermometer).
Preparation of extracts- All the
extracts of assigned assays had different solvent systems foe extraction. The
samples were extracted in triplicates – sample A (mature leaves), sample B
(young leaves), sample C (stolon). All extractions were carried out in cold
condition (esp. for enzymatic assays). One gram of sample per 10 ml of
respective solvent (concentration of sample = 100mg/ml) used.
Determination of
antioxidant status- For both enzymatic and non-enzymatic
antioxidants analysis, the samples were prepared as they were procured after
the applied conditions from Coriandrum
sativum L. using standard methods, with few modifications as per laboratory
convenience.
Enzymatic antioxidants- SOD was
assayed according to the method of Kakkar [9]. Catalase activity was assayed
following the method of Luck [10]. Peroxide activity was assayed by the method
from Sadasivam and Manikam [11].
Non-enzymatic antioxidants- Ascorbic
acid was quantified by spectrophotometric assay method [12]. Tocopherol was
estimated in the plant samples by the Emmerie-Engel reaction [13]. The amount
of total phenols in the plant tissues was estimated by the method proposed by
Mallick and Singh [14].
Biochemical assay- Protein
estimation was assayed by the Lowry’s method [11].
RESULT AND DISCUSSION
Fig. 1: showing
abnormality of physical damage found on day 3
The values presented in
Table 1 and Table 2 states that Coriandrum
sativum Linn. shows considerable amount of antioxidants,which are monitored
over the period of 9 days. During this period the temperature was monitored and
averaged out to be -2.2oC. The values depicted in the tables are the
means of triplicates of all samples.
The value presented in Table 1 showed the sample Coriandrum sativum Linn. possess
considerable amount of activities of all enzymes analyzed. It is evident from
the values that enzyme catalase was the only enzyme which was found in stolon
region of each day samples, whereas other two enzymes were found in all
triplicates of each day. The results presented in Table 2 revealed that the
samples also contain considerable amount of all the non-enzymatic antioxidants
analyzed. All the samples were analyzed fresh under respective treated
conditions. Day 3 showed abnormal moisture and ice-crystal formation during the
storage conditions (Fig. 1), which is assumed to cause defective results in the
overall study plan. Table 1shows the activity of SOD over the study duration.
There is an abnormal increment on third day which was found physically damaged
in 9th day, whereas 6th day showed a moderate increase.
Thus, making it uncertain to evaluate the trend. It further showed the activity
of CAT. Here, there is a surprising drop in the Day 3 and the remaining study
days show a steep decline in activity thus bringing to a conclusion that there
is a significant decrease in catalase activity as the storage period increases.
Table 1 also exhibits the activity of POX. The enzyme activity showed sharp
increase as per the degree of sample deteriorate (Day3) from Day 0 and Day 9. Along with
enzymatic antioxidants the sample was assayed for vitamin C, vitamin E and
total phenolic content. Table 2 shows the activity
of ascorbic acid estimation Day3 shows as abruptly large increase of ascorbic
acid, whereas the amount reduces as further increase in duration. The vitamin C
amount is for high from the literature value (135 mg/100g of sample) which
further makes it an uncertain observation. It also shows the amount of vitamin
E is found to be moderately less than the literature value. The amount of
vitamin E showed a peak at Day 6 and decreases further over study duration for
total phenolic content estimation it shows a peak whereas Day 3 showeda reduced
phenolic content, which makes it uncertain to draw conclusion as it contradicts
with the hypothesis that phenolic content should increase with increase in
duration of storage.Table 3shows estimation of protein. Overall, through
present study it can be concluded as aCoriandrum
sativum Linn.is a potent source of antioxidants as well as storage duration
and degree of deteriorate has a role in change antioxidant levels in the plant.
Table 1: Enzymatic antioxidant activities in Coriandrum sativum Linn
|
Enzymes |
Day 0 |
Day 3 |
Day 6 |
Day 9 |
|
Superoxide dismutase (U#/g leaf) |
15.60 |
58.15 |
30.35 |
63.11 |
|
Catalase (U$/g leaf) |
63.16 |
11.32 |
9.30 |
7.95 |
|
Peroxidase (U*/g
leaf) |
0.91 |
1.19 |
1.03 |
1.40 |
Notes: # 1 Unit = Amount of enzyme that causes 50%
reduction in NBT oxidation
$ 1 Unit = Amount of enzyme required to
decrease the absorbance at 240nm by 0.05
Units/minute
* 1
Unit = Changes in absorbance at 436 nm/minute
Table 2: Non-enzymatic antioxidant levels in Coriandrum sativum Linn.
|
PARAMETER |
Day 0 |
Day 3 |
Day 6 |
Day 9 |
|
Ascorbic acid (mg/g
leaf) |
2.2 |
2.41 |
2.27 |
2.29 |
|
Tocopherol (µg/g
leaf) |
17.3 |
18.6 |
17.2 |
16.2 |
|
Total phenols (mg/g
leaf) |
1.13 |
0.42 |
1.78 |
1.26 |
CONCLUSION- As monitored the
overall antioxidant status of the plant decreases considerably during storage
condition. During storage, these antioxidants react with free radical, produced
by aerial oxygen and depleted, decreasing their concentration, despite being
stored at refrigerator conditions. The study limits itself in uncertain about
the effects that this duration will cause on human health. Most common change
that occurs in green vegetables during storage conditions (processing) is
conversion of chlorophyll to pheophytin, causing a color change from bright
green to olive brown which is undesirable to consumers. This observation was
made in ourresearch on Day 3. Thus, emphasizing the need to find optimal
storage conditions.The research opens new avenues to be explored if study plans
were made to monitor effect on antioxidant status of any plant species by
varying storage temperature and duration so that analysis can be made to
estimate optimal storage temperature and duration for idle consumer
acceptability and palatability at a house-hold as well as commercial or
industrial level.
REFERENCES
1.
Keith S. Coriander: Overview
of potential health benefits. Nutrition
today, 2016; 51 (3): 151-161.
2.
Muhammad Isa Khan et.al. Nutrition and medicinal aspects
of coriander (Coriandrum sativum L.).British
food journal. Emerald publishing limited, 2013; 115 (5):743-755.
3.
Sreerupa Sarkar et. al. Effect of storage and
preservatives on Antioxidant status of some refrigerated Fruit juices. International Journal of Current
Microbiology and Applied sciences.2014; 3 (7); 1007-1013.
4.
S. Bhat. et. al. Coriander (Coriandrum sativum
L.): Processing, nutritional and functional aspects. African Journal of Plant sciences.2014; 8 (1): 25-33.
5.
Ulla gaddi Rajeshwari et.al. Medicinal benefits of Coriander (Coriandrum sativum L.). Spatula DD,
2011; 1 (1): 51-58.
6.
Muhammad Khuram Shahwar et.al. Characteristics of coriander (Coriandrum sativum L.) seeds and leaves:
volatile and non-volatile extracts. International
journal of food properties. 2012; 5 (4): 736-747.
7.
C. Serea et.al. Effect of storage temperature on
the ascorbic acid content, total phenolic content and activity in Lettuce (Lactuca sativa L.). The journal of animal and plant sciences, 2014; 24 (4); 1173-1177.
8.
Manoranjankar and D. Mishra.
Catalase, peroxidase and polyphenol oxidase activities during Rice leaf
senescence. Plant physiol. 1976;
57:315-319.
9.
Kakkar P, Das B,
Vishwanathan PN. A modified spectrophotometric assay of superoxide dismutase.Indian J Bio-phy, 1984; 21: 130-162.
10. Luck H. Methods in enzymatic analysis. 2nded. New York: Bermeyer
Academic press; 1974.
11. Sadasivam S. and Manikam A. Biochemical methods. 3rd edition, New
age International Publishers (1996).
12. Roe JH, Keuther CA. The Determination of ascorbic acid in whole
blood and urine through 2,4-dinitrophenylhydrazine derivative DE hydro ascorbic
acid. J Bio Chem. 1943; 147: 399-407.
13. Rosenberg HR. Chemistry and physiology of the vitamins, New York:
Interscience Publisher: 1992, p 452-453.
14. Mallick CP, Singh MB. Plant enzymology and plant histoenzymology,
New Delhi, Kalyani publishers: 1980, p.179.