Determination of total phenolic and flavonoid contents, antioxidant and antimicrobial activities of some important salep orchids

In the human body, oxidative stress imposed due to the increase in the concentration of free radicals such as reactive oxygen species (ROS) contributes to the initiation and progression of different diseases. The synthetic antioxidants have low efficacy with side effects, for that plant-derived natural antioxidant can prevent oxidative stress by reducing the risk of having these diseases. In the present study, the methanolic extracts of two traditionally used medicinal plants (leaf and flower) have tested for their antioxidant capacity, α-amylase enzyme inhibitory activity and determination of total phenolic and flavonoid content in the plant extracts. The antioxidant activity was evaluated by a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. The highest DPPH radical scavenging was shown by Clerodendrum infortunatum (IC50 = 71.95±0.51μg/mL) whereas leaf and flower of Hibiscus rosa sinensis showed moderate antioxidant activity (IC50 = 98.74±1.91 and 117.23±7.72 μg/mL) respectively. Among the tested plant extracts, the highest amount of total phenolic and flavonoid content was found in the methanolic extract of C. infortunatum with TPC of 87.07±9.22 mg GAE/g and TFC 34.40±2.00 mg QE/g. The antidiabetic activity of plant extracts was evaluated by the α-amylase enzyme inhibition assay. The leaf extract of C. infortunatum showed moderate α-amylase inhibition activity (IC50 = 118±4.80 μg/mL) whereas the standard acarbose has (IC50 = 12.96±0.22 μg/mL).

Emilia sonchifolia (L.) D.C. is a medicinal plant from the family Asteraceae known for a wide range of ethnomedicinal uses such as management of inflammatory diseases, pains, cancer, diabetes, cataract, asthma and liver disease. This research was aimed at assessing the antioxidant potential and quantitative determination of phenolic and flavonoid contents of the extract and fractions of Emilia sonchifolia leaves. The leaves of the plant were processed, extracted and partitioned successively and exhaustively with dichloromethane (DCM) and ethyl acetate. Phytochemical screening was carried out on the methanol extract using standard methods. Antioxidant evaluation of the methanol extract and fractions of Emilia sonchifolia leaves was carried out using Ferric Reducing Antioxidant Power (FRAP) assay and 2, 2, diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Quantitative determination of total phenolic content and total flavonoid content was done. The extraction and partitioning yielded the crude extract and respective fractions. The phytochemical screening revealed the presence of tannins, saponins, flavonoids, alkaloids and cardiac glycosides. Antioxidant evaluation of the crude extract and fractions of the plant exhibited significant (p<0.001) antioxidant activity in both assay though not comparable with the standard agent, ascorbic acid. In DPPH assay, the highest percentage inhibition was observed in ethyl acetate fraction (62%) followed by the extract (61%), DCM fraction (55%) and aqueous fractions (54%) at 100 µg/mL. In FRAP assay, the highest reducing power was exhibited by ethyl acetate fraction (0.457 nm) followed by the extract (0.444 nm), DCM fraction (0.441 nm) and aqueous fraction (0.439 nm). Although these activities were significant, they were not comparable to that of the standard drug ascorbic acid (0.914 nm). In total phenolic content assay ethyl acetate fraction had the highest phenolic content (5.804 mg/g), followed by crude extract (2.500 mg/g). The total flavonoid content was observed to be highest in ethyl acetate fraction (10.556 mg/g), followed by crude extract (4.444 mg/g). From this research work it was observed that Emilia sonchifolia leaves have a good antioxidant activity which could be responsible for its wide range of ethnomedicinal activities and this lends scientific credence for the use of this plant in the management of disease conditions.

Background: Free radicals are chemical species a molecule, atom with unpaired electrons and reactive as oxidizing agent which cause oxidize stress in tissue. Antioxidants are substances that can protect cells from free radicals by releasing electrons to neutralize free radicals. Tamarillo peel contains phenolic and flavonoid compounds which have antioxidant activity. The aim of this study was to determine the antioxidant activity, total phenolic and flavonoid content of the ethanol extract of tamarillo peel. Methods: In this research, the maceration method was used to extract phenolic and flavonoid components from tamarillo peel with ethanol 70% solvent. Total phenolic and flavonoid content was determined with UV-vis spectrophotometer. Total phenolic content determined using the Folin-Ciocalteu reagent and expressed in GAE (Garlic acid equivalent) and the total flavonoid content used the AlCl-3 reagent and expressed in QE (Quersetin equivalent). Then, tamarillo peel ethanol extract was tested the antioxidant activity using the DPPH method. Result: The results showed that the total polyphenol content was 66.6242 mg GAE/g extract or 6.66% w/v extract, total flavonoid content was 0.74246 % w/v or 7.4246 mg QE/g extract. Antioxidant activity in IC50 value was 47.9460 ppm. Conclusions: From the results of the research conducted, it can be seen that the ethanol extract of tamarillo can provide an antioxidant effect in the very strong category.

This study explores the antioxidant potential and secondary metabolite profiles of Terminalia chebula and Glycyrrhiza glabra, medicinal plants native to Swat, Pakistan. Terminalia chebula, or black myrobalan, is known for its antioxidant and anti-inflammatory properties, while Glycyrrhiza glabra, commonly known as licorice, has a rich history of traditional medicinal use for over 4000 years. The study focuses on evaluating the total phenolic and flavonoid contents, as well as the antioxidant activity of both plants. The study explores the importance of secondary metabolites, including alkaloids, glycosides, flavonoids, phenolics, saponins, tannins, terpenes, anthraquinones, essential oils, and steroids, in both Terminalia chebula and Glycyrrhiza glabra. The antioxidant activity of these plants is crucial in combating oxidative stress and preventing various health conditions associated with reactive oxygen species (ROS). The methodology involves the collection of seeds from local markets, grinding them into powder, and extracting them with 70% ethanol. The samples are then subjected to various analyses, including total phenolic and flavonoid content determination and antioxidant activity evaluation using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Results indicate that both Terminalia chebula and Glycyrrhiza glabra exhibit significant levels of total phenolic and flavonoid contents, with remarkable antioxidant activity. Glycyrrhiza glabra demonstrates higher total phenolic and flavonoid contents compared to Terminalia chebula. The study concludes that these medicinal plants are rich sources of bioactive compounds with potential therapeutic applications, highlighting the importance of exploring and harnessing the pharmacological benefits of traditional medicinal plants for human health. © 2020 The Author(s)

Uraria picta Desv. belonging to family Leguminosae: Papilionoidae is one of the important constituent of “Dashmoolarista”, a well-established Ayurvedic drug of Indian system of medicine. The objectives of the present study were to determine the free radical scavenging activity, total phenolic and flavonoid contents in leaves, stem and roots of U. picta. Powdered samples of leaves, stem and roots were subjected to successive extraction with solvents of increasing polarities i.e. Ethanol, Water: Ethanol (Aqua- alcoholic) (20: 80) and Water (aqueous) using soxhlet apparatus. Total phenol, flavonoid and antioxidant activity were determined by using Folin-Ciocalteau method, aluminum chloride colorimetric technique and DPPH free radical scavenging methods respectively. The results exhibited the maximum phenolic (1.991±0.299%) and flavonoid (2.865±0.11%) contents in ethanolic extract of leaves. For stem, the highest phenolic content (1.208±0.115%) and highest flavonoid content (22.189±2.7%) were detected in aqueous and ethanolicextracts respectively. For roots, both the maximum phenolic (3.554±0.004%) and flavonoid (0.497±0.507%) contents were found in Aqua- alcoholic extract of roots. The ethanolic extracts of leaves and stem and aqueous extract of roots were found to contain the lowest IC50 and hence, the maximum antioxidant activity. Based on the findings, it can be concluded that among the different extracts of leaves, stem and roots of U. picta, the ethanolic extracts of leaves and stem and aqueous extract of roots exhibited the more promising antioxidant activity due to the presence of phenolic and flavonoid compounds.

Yograj guggulu vati (YGV), a polyherbal formulation is recommended for the management of diseases like arthritic, anodyne or analgesic, spasm, muscle relaxant, flatulence, digestive problem, cough, hyperglycaemia, fat burner and obesity. Though Yograj guggulu vati is widely used for the treatment of diseases in Ayurvedic System of Indian Medicine, but till date, it’s Phenolic and flavonoids contents and contamination studies have not been carried. In the present article, we evaluated the total phenolic and flavonoids contents and contamination of YGV. Total phenolic contents were evaluated by Folin Ciocalteu reagent. Aluminum chloride colorimetric method was used for the determination of total flavonoid contents. Contamination study such as microbial load was also performed. Microbial load study revealed that total bacterial counts and total fungal counts were under limits. The total phenolic content and total flavonoid content were 190.16 mg/g and 20.87 mg/ g dry extract respectively. Microbial load studies showed that the formulation has a good quality and purity. Presence of abundance phenolic and flavonoids compound indicated that YGV can be used for different biological activities.&#x0D; Keywords: Microbial load, Yograj Guggulu Vati, total phenolic contents

Black garlic is produced by processing multi-bulb garlic (Allium sativum) or single-bulb garlic in high temperature and high humidity for several days. Black garlic has many health benefits, such as an antioxidant activity resulting from its compound, including groups of flavonoid and phenolic compounds. This study aimed to analyze the effect of aging time on multi-bulb and single-bulb black garlic on the content of total phenolic, flavonoid, and antioxidant activity. Black garlic was processed at a 60-70°C heating temperature and 70-80% relative humidity for 25 days. Determination of total phenol and flavonoid contents was conducted using spectrophotometric methods with gallic acid as a standard of total phenolic and quercetin as a standard of flavonoid, while the antioxidant activity was determined by DPPH radical reduction. The results showed that total phenolic contents (% w/w GAE), flavonoids contents (% w/w QE), and EC50 values at 0 until day 25 increased on a particular day in multi-bulb and single-bulb black garlic. The optimal total phenolic content of both black garlic was obtained by heating for 20 days, flavonoid content of multi-bulb garlic for 10 days, and single-bulb black garlic for 15 days. Highest antioxidant activity was obtained on days 20 and 25 for single-bulb black garlic and multi-bulb black garlic, respectively. The aging time of black garlic affects total phenolic, flavonoid content, and antioxidant activity. In general, longer processing time caused an increase in the total phenolic content, flavonoid content, and antioxidant activity of both black garlics. Multi-bulb black garlic showed higher phenolic or flavonoid content and antioxidant activity than single-bulb black garlic.

The lichens synthesize a large number of secondary metabolites and most of these compounds are unique to lichen. The present study provides data concerning the chemical characterization and determination of total phenolic and flavonoid contents of lichen extracts of Umbilicaria crustulosa. Chemical profiling of the extracts was done by high-performance liquid chromatography coupled with a UV detector (HPLC/UV), while the determination of total phenolic and flavonoid contents was done by the spectrophotometric method. HPLC analysis of the acetone and methanol extracts of U. crustulosa lichen revealed the presence of the methyl-orselinate, lecanoric acid, crustinic acid, haematommic acid, gyrophoric acid, methyl lecanorate, physodic acid, atranorin and chloroatranorin as the main compounds. The most abundant compounds of the acetone and methanol extracts were the tri-depside gyrophoric acid (59.27 % and 58.32 %) and didepside lecanoric acid (7.41 % and 11.43 %). The results of the total phenolic content (TPC) and total flavonoid content (TFC) show that the acetone extract had higher values of TPC (205.46 mg GA/g) and TFC (290.18 mg RE/g; 160.50 mg QE/g). The investigated extracts of the lichen U. crustulosa can be used as a significant source of biologically active compounds.

Tandui (Mangifera rufocostata Kosterm.) is a species of the genus Mangifera which is known to contain phenolic and flavonoid compounds and is one of the plants used as an alternative medicine by the people of South Kalimantan. The purpose of this study was to determine the total phenolic and flavonoid content of 70% ethanol extract of tandui bark. Qualitative analysis using phenolic and flavonoid phytochemical screening with 3% FeCl3, Mg-HCl reagents and Thin Layer Chromatography (TLC) with spot appearance 10% FeCl3 for phenolic and 5% AlCl3 for flavonoid compounds. Quantitative analysis using UV-Vis spectrophotometry, determination of total phenolic content using Folin-Ciocalteu reagent with gallic acid standard solution, while determination of total flavonoid content using AlCl3 reagent with quercetin standard solution. The results of identification of phenolic and flavonoid compounds by phytochemical screening and TLC showed that 70% ethanol extract of tandui bark contained phenolic and flavonoid. The results of the determination of the total phenolic content using UV-Vis spectrophotometry were 471.3126 mgGAE/g or 47.1312%, while the total flavonoid content was 872.075 mgQE/g extract or 87.2075%. Based on these results, it can be concluded that 70% ethanol extract of tandui bark contains secondary metabolites in the form of phenolics and flavonoids which have potential as medicine.

Aims: This study aimed to investigate the total phenolic and flavonoid content and DPPH free-radical scavenging activity of Vernonia amygdalina planted in Mekong Delta. The optimized conditions for maceration of pandan leaves included drying method, ratio of pandan leaf powder-to-solvent, and extraction time.&#x0D; Methodology: The fresh pandan leaves were divided into two equal portions, subjected to different drying methods: shade and oven drying. The dried leaf powder was macerated in ethanol at room temperature. The maceration was conducted with 3 different ratios of pandan leaf powder-to-solvent (w/v) (1:10, 1:15 and 1:20), and the extraction time was 1, 2 and 3 days. The total flavonoid content was determined using aluminum chloride method whereas the total phenolic content was assessed using Folin-Ciocalteu assay. Meanwhile, the antioxidant activity of the plant extracts was quantitatively evaluated using DPPH test.&#x0D; Results: The results indicated that the best conditions for maceration of pandan leaves were 1:10 shade-dried leaf powder-to-solvent ratio in 1-day extraction time. Accordingly, the total flavonoid and phenolic content was found to be the highest value of 130.02 ± 2.24 mg QE/g of dried extract and 100.67 ± 1.76 mg GAE/g of dried extract (p &lt; 0.05), respectively. The lowest IC50 of DPPH free-radical scavenging activity of pandan leaf extract was found to be 0.90 ± 0.02 mg/mL (p &lt; 0.05). In addition, the Pearson’s correlation coefficient between IC50 of DPPH free-radical scavenge activity and total flavonoid content was R2 = 0.74 compared to that of phenolic content with the value of R2 = 0.69, indicating that the IC50 of DPPH free-radical scavenge capacity of pandan leaves was influenced chiefly by flavonoid compounds.&#x0D; Conclusion: There was a significant difference in phenolic and flavonoid content and DPPH free-radical scavenging activity between shade-dried and oven-dried pandan leaf extracts.

This experiment aims to determine the correlation of total phenolic and flavonoid content of jati putih leaves fraction (Gmelina arborea Roxb.) towards Antioxidant activity . Sample was extracted by maceration method using ethanol 70% to obtain the ethanol extract (EE), followed by liquid-liquid extraction method to obtain fraction of ethyl acetate (EA) and n-Hexane (EH). The phytochemical screening and determination of total phenolic and flavonoid content were done by colorimetric method. Antioxidant activity were done by DPPH, FRAP and ABTS methods. Phytochemical screening showed positive results for flavonoids, phenolic and saponins. The largest total phenolic content was found on EA (11,59 µg/ml ± 0,3 %b/b EAG) and the largest total flavonoid content was on EA (3,88 µg/ml ± 0,02 %b/b EK). The total phenolic and flavonoid content of Jati putih leaves has a correlation with antioxidant activity. The coefficient correlation of activity on reducingDPPH radical was 56,7% (total of phenolic content) and 57,8% (total of flavonoid content) and on iron reduction power in FRAP method was 99,9% (total of phenolics and flavonoids content). The relationship with the activity in reducing radical ABTS obtained coefficient correlation of 57,0% and 58,1% for total phenolic and flavonoids contents, respectively.

Background: Secondary metabolites of plants such as phenol and flavonoids have an extreme potential for neutralizing free radicals. The antioxidant and cytotoxic activities of plants are related to phenolic or flavonoids compounds. The occurrence of drug resistance to antimicrobial drugs has led to use of medicinal herbs in treatment of infections. Antibiotic resistant of Staphylococcus aureus has become a major problem in the treatment of diseases. Objectives: The aim of this study was determination of total phenolic content (TPC) and total flavonoids content (TFC) of Polygonatum orientale Desf and Tilia dasystyla and evaluation of their anti-bacterial effects on Staphylococcus aureus bacterium. Investigation of TPC of P. orientale Desf and T. dasystyla has not been reported before. Methods: Total phenolic and flavonoid content of P. orientale Desf and T. dasystyla extracts were determined using colorimetric methods of Folin-Ciocalteu and aluminum chloride. Antimicrobial activities of the extracts were evaluated by microdilution broth and disc diffusion methods to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. Results: The results showed that TFC of P. orientale Desf with the value of 7.9 ± 0.040 mg/g DW extracted with diluted water solvent and boiling method and TPCs of T. dasystyla with the value of 62.13 ± 0.073 mg/g DW extracted with methanol solvent and boiling method were the highest amount. Methanol extract of P. orientale Desf had more antibacterial activities with the MBC and MIC values of 0.140 mg/mL and 8±0.4 mm zone of inhibition. Conclusion: Tilia dasystyla and P. orientale Desf contain bioactive compounds such as phenolic and flavonoids that can be used as promising option in pharmacognostical studies for treatment of S. aureus infections.

Objective The present study was designed to evaluate the in vitro antioxidant and DNA nicking potential of various extracts and fractions of Pterospermum acerifolium (L.) Willd (Family: Stericuliaceae). Research design and methods Antioxidant properties of the extracts and fractions was assayed by DPPH scavenging activity, non-site-specific and site-specific OH radical scavenging activity mediated 2-deoxy- d -ribose degradation, total antioxidant activity and lipid peroxidation assay by using rat liver homogenate. DNA nicking assay was studied by PT257R/T plasmid. Estimation of total phenolic content and total flavonoid content was done. Further HPTLC fingerprint of active fractions was performed. Results Ethyl acetate fractions of leaves, flowers and bark exhibited potent antioxidant property and DNA protective effect compare to all the other extracts and fractions. Total phenolic and flavonoid content determination was also showed ethyl acetate fractions were rich in phenolic and flavonoid contents. HPTLC fingerprint revealed the total number of peaks present in the active ethyl acetate fractions of leaves, flowers and bark. Conclusion The present study indicated that, ethyl acetate fractions of leaves, flowers and bark showed effective antioxidant and DNA protection activity and it could be the initiation for various other pharmacological studies on those fractions.

Objectives: The objectives of this research were to evaluate antioxidant activity from different polarities rice bran extract of three varieties of rice using two methods of antioxidant testing which were FRAP (Ferric Reducing Antioxidant Power) and DPPH (2,2-diphenyl-1-picrylhydrazyl), and correlation of total phenolic, flavonoid and carotenoid content with their EC50 of FRAP and IC50 of DPPH antioxidant activities. Methods: Extraction was conducted by reflux using different polarity solvents. The extracts were evaporated using rotary evaporator. Determination of total phenolic, flavonoid and carotenoid content, antioxidant activities using FRAP and DPPH assays were performed by UV-visible spectrophotometry and its correlation with EC50 of FRAP capacities and IC50 of DPPH scavenging activities were analyzed by Pearson’s method. Results: Ethanolic rice bran extract of black rice showed the lowest EC50 of FRAP capacity 64.35 µg/ml and IC50 of DPPH scavenging activity 23.92 µg/ml. The highest phenolic content, flavonoid content and carotenoid content were also given by ethanolic rice bran extract of black rice. There were significantly negative correlation between total phenolic content and carotenoid content in rice bran extract of red rice and black rice with their IC50 of DPPH. Conclusions: All of rice bran extracts (except n-hexane rice bran extract of black rice and ethanolic rice bran extract of white rice) were very strong antioxidant, by DPPH assay. Phenolic and carotenoid compounds in rice bran extracts of red rice and black rice were the major contributor in antioxidant activity by DPPH assay. Rice bran extracts of black rice had linear results by FRAP and DPPH assays.

Nyctanthes arbortristis, commonly known as the night-jasmine, is a plant rich in bioactive compounds with potential therapeutic benefits. This study aimed to evaluate the antioxidant properties and cytotoxic effects of Nyctanthes arbortristis bark extracts on SW982 rheumatoid arthritis cell line in vitro. Sequential solvent extraction method was employed to obtain extracts with varying polarities. The antioxidant potential of the extracts was assessed using DPPH, ABTS, NO, and H2O2 radical scavenging assays and total phenolic and flavonoid content determination. Cytotoxicity was evaluated using MTT assay on SW982 cells. Results revealed that the bark extracts exhibited significant antioxidant activity, with the methanol extract showing the highest radical scavenging activity, total phenolic content and total flavonoids contents. Furthermore, the bark extracts demonstrated concentration-dependent cytotoxic effects on SW982 cells, with the ethyl acetate extract exhibiting the most potent cytotoxicity. These findings suggest that Nyctanthes arbortristis bark extracts possess substantial antioxidant potential and cytotoxic effects against SW982 rheumatoid arthritis cells, indicating their potential as therapeutic agents in the management of rheumatoid arthritis. Further investigations are warranted to elucidate the underlying mechanisms and evaluate their efficacy in vivo.