J Bangladesh Agril Univ 19(2): 178–183, 2021 https://doi.org/10.5455/JBAU.62120 ISSN 1810-3030 (Print) 2408-8684 (Online) Journal of Bangladesh Agricultural University Journal home page: http://baures.bau.edu.bd/jbau Variation of Phenolics, Antioxidant Activity and Carotenoids Contents in Some Medicinal Plants H.M. Munjur Murshed, Md. Nesar Uddin, M. Ashrafuzzaman Department of Crop Botany, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh ARTICLE INFO ABSTRACT Article history Plants being important source of medicine play significant role in human health. Total phenolics, free Received: 09 Mar 2021 radical scavenging capacity and carotenoids contents in six medicinal plants [Peltata (Cyclea peltata), Accepted: 01 Jun 2021 Pudina (Mentha piperita), Bon tulsi (Ocimum americanum), Kalo tulsi (Ocimum sanctum), Akanadi Published: 30 Jun 2021 (Stephania japonica) and Gulancha (Tinospora cordifolia)] from two families (Lamiaceae and Menispermaceae) available at the Bangladesh Agricultural University botanical garden were studied Keywords in the present experiment. Total phenolics content in the six medicinal plants ranged from 340.03 (M. Phenolics, Medicinal plants, −1 piperita) to 890.58 (O. americanum) mg GAE 100 g leaf fresh weight. The IC50 value for scavenging 2, Carotenoids, Antioxidant 2- diphenyl-l- picrylhydrazyl (DPPH) free radicals ranged from 3.27 (O. americanum) to 57.85 (T. −1 −1 Correspondence cordifolia) mg mL leaf extract and carotenoid content was maximum in M. piperita leaf (0.380 mg g M. Ashrafuzzaman fresh weight) among the six test species. The high content of phenolics in O. americanum represents : [email protected] the plant species as an important natural source of antioxidants with high potential value for drug preparation. Copyright ©2021 by authors and BAURES. This work is licensed under the Creative Commons Attribution International License (CC By 4.0). Introduction Medicinal plants contain a complex set of chemical M. piperita L., commonly known as pudina in Bangla, a substances that influence the human and other medicinally important plant belongs to the Family organisms in different and versatile ways. Many Lamiaceae. This family is a rich source of polyphenolic secondary metaboites (Islam et al., 2018a; Islam et al., compounds and hence could possess strong antioxidant 2018b), anti-inflammatory, antimicrobic, spasmolytic, properties (Bimakr et al., 2011). Multiple biological and neuroprotective actions (Rice-Evans et al., 1997). activities of Peppermint essential oil and extract might be The medicinal plants selected for the present ascribed to the presence of some components, such as investigation such as Peltata (C. peltata), Pudina (M. flavonoids, phenols, carotenes, betaine, choline, tannins piperita), Bon tulsi (O. americanum), Kalo tulsi (O. and volatile oil composed primarily of menthol, sanctum), Akanadi (S. japonica) and Gulancha (T. menthone, menthofuran and menthyl acetate (Leung, cordifolia) have long been used in the folk medicine due 1980). to their potential health promoting and pharmacological attributes. The juice of C. peltata leaves is applied to O. sanctum L. has also been suggested to possess anti- abscesses and decoction is given in dysentery (Kirubha et fertility, anti-cancer, anti-diabetic, anti-fungal, anti- al., 2012). The leaves of C. peltata are being used microbial, hepatoprotective, cardioprotective, anti- traditionally as coolant, antidandruff, antipyretic and emetic, anti-spasmodic, analgesic, adaptogenic and diuretic drug (Kingston et al., 2007; Bhandary et al., diaphoretic action (Prakash and Gupta, 2005). With 1995). The paste prepared from leaves with water is regard to folk medicine, O. americanum is used to treat taken orally along with cow’s milk two times a day for a insomnia, constipation, cough, and microbial infections period of two days to get relief from lumbago (Lalitha et (Yucharoen et al., 2011). al., 2011). Cite This Article Murshed, H.M.M., Uddin, M.N., Ashrafuzzaman, M. 2021. Variation of Phenolics, Antioxidant Activity and Carotenoids Contents in Some Medicinal Plants. Journal of Bangladesh Agricultural University, 19(2): 178–183. https://doi.org/10.5455/JBAU.62120 Murshed et al. S. japonica L. belongs to the family Menispermaceae, a was kept in dark condition for 30 minutes and slender wiry climber or twining shrub is widely used in centrifuged for 5 minutes at 1500 rpm and then its the traditional medicine of Bangladesh in treatment of a supernatant was treated as working sample extract. An wide range of diseases and disorders including aliquot amount of the extract was used for determining inflammation, cancer, asthma, fever, sleep disturbance, total phenolics content or DPPH scavenging activity. edema, and bone fracture (Jahan et al., 2010). Especially Gallic acid was used here as standard. Exactly 330 μL its leaves, which are extensively used to treat different from different concentrations of gallic acid solutions or kinds of painful conditions, more specifically, the suitable amount of plant extracts were taken into a 50 crushed leaves for body pain (Seraj et al., 2013; Jahan et mL test tube. Then 0.16 mL of Folin-Ciocalteu reagent al., 2010) and warmed leaves for rheumatism (Rahman and 3 mL of Na2CO3 (10%) solution was added to 1 mL of et al., 2007). gallic acid solution. The mixture was kept in dark condition for half an hour at room temperature (25°C). T. cordifolia or Gulancha finds a special mention for its Then absorbance was measured at 760 nm. The use in folk and tribal medicine in different parts of the absorbance value is the reflection of the total phenolics country since time immemorial. It has been shown to content in the sample. After plotting the absorbance in possess anti-allergic (Nayam palli et al., 1986), anti- ordinate against the concentration a linear relationship diabetic (Wadood et al., 1992), anti-hepatotoxic and was obtained which was used as a standard curve for the anti-pyretic (Rege et al., 1984) properties. determination of the total phenolics content of the test samples. Analyzing these plants for their total soluble phenolics, carotenoids and anti-oxidative power to scavenge free DPPH radical scavenging assay radical will provide a better understanding of these Free radical scavenging activity of the plant extracts was medicinal plants. Keeping this view in mind the present determined by using a stable 2,2-diphenyl-1- study, therefore, was conducted to assess and compare picrylhydrazyl radical (DPPH) (Brand-Williams et al., total phenolics and carotenoids contents in above 1995). DPPH is a free radical of violet colour. The mentioned medicinal plants; and to determine free antioxidants in the sample scavenge the free radicals and radical scavenging ability of the plant extracts. turn it into yellow colour. The change of colour from violet to yellow is proportional to the radical scavenging Materials and Methods activity. Briefly, the assay contained 2.7 mL of 0.1 mM Plant material DPPH in methanol and made up to 3 mL with 300 μL plant The medicinal plants [C. peltata (Menispemaceae), M. extracts (working sample). The contents were mixed well piperita (Lamiaceae), O. americanum (Lamiaceae), O. immediately and then incubated for 30 min at room sanctum (Lamiaceae), S. japonica (Menispemaceae) and temperature (25°C). The degree of reduction of T. cordifolia (Menispemaceae)] available at the absorbance was recorded at 517 nm using DR 6000 UV Bangladesh Agricultural University Botanical Garden Spectrophotometer. were choosen for the study. The percentage of scavenging activity was calculated as: Sample collection (Ac – As)/ Ac × 100 For each sample three different healthy plants from where ‘Ac’ is the absorbance of control (without extract) three different colonies were selected and considered as and ‘As’ is the absorbance of sample with plant extract. three replicates. Tender leaves from the selected plants Percentage of radical scavenging activity was plotted and colonies were collected in the morning and against the corresponding concentration of the extract immediately placed in zip lock bags with proper tagging to obtain IC50 value. IC50 is defined as the amount of to avoid moisture loss. Leaf samples were immediately antioxidant material required to scavenge 50% of free brought to the laboratory for chemical analyses. The radical in the assay system. The IC50 values are inversely collected leaves were chopped into small pieces proportional to the antioxidant activity (Nisha et al., separately to produce working samples for analysis. 2009). Total phenolics content assay Total carotenoids Total phenolics were assayed with the method modified Total carotenoids can be determined in a whole pigment after Albano and Miguel (2011). Exactly 5 g of the extract of green plant tissue by spectrophotometer working samples for leaf were taken to a 250 mL beaker (Lichtenthaler, 1987). From the fresh composite leaf and 100 mL ice cooled methanol were added to it and sample, 50 mg were taken in a glass bottle and 200 μL then each sample was homogenized for 2 minutes using distilled water were added to it. Then 16 mL ethanol a Homogenizer (model- OV-5 VELP, Italy). The mixture 179 Total Phenolics in Medicinal Plants were added and shaken properly and finally, the content M. piperita leaf extract contained the highest amount of was kept in dark condition for 24h. Absorbance reading carotenoids (0.380 mg g-1 FW) followed by the second was taken in the following day in a spectrophotometer highest in T. cordifolia (0.296 mg g−1 FW). The (DR 6000, Hach, USA) at 470, 649, 664 and 750 nm wave carotenoids content was minimum in O. americanum lengths. Afterward, amount of total carotenoids (sum of leaf (0.160 mg g−1 FW) which was statistically in similar carotene and xanthophyll) were calculated using the rank to S. japonica (0.189 mg g-1 FW). The leaves of other following formulae: species showed the carotenoids content in the leaf Carotenoids extract of Cyclea peltata (0.257 mg g−1 FW) and Ocimum (Cx+c) = (4.785 A470+3.657 A664−12.76A649) ×16.2/FW americanum (0.233 mg g−1 FW) were intermediate.