Activity Of Different Extracts Research Articles

Comparison of Antioxidant and Antiacetylcholinesterase Activities of Different Extracts of Tunisia Maclura pomifera (Rafin.) Schneid Fruit In Vitro and In Vivo

Background: Maclura pomifera a member of Moraceae family, is a tropical plant with ethnobotanical uses. Objectives: The present study aimed to evaluate bioactive compounds, antioxidants, and acetylcholinesterase (AChE) inhibitory activities of different extracts of Tunisia M. pomifera (Rafin.) Schneid fruit in vitro and in vivo. Methods: Organic extracts in different polarities (chloroform, ethyl acetate, and acetone) were extracted from different parts of the fruit of M. pomifera (exocarp, mesocarp, and pips). Phenolic content, antioxidant activity, and anti-AChE activity were determined. The anti-amnesic effects of ethyl acetate extract of the exocarp of M. pomifera were measured in galactose-induced memory deficit mice by the Y maze. The levels of biomarkers and AChE activity were determined in brain tissues. Results: The obtained results showed that the ethyl acetate extract of exocarp contains the highest content of flavonoids and polyphenols 22.3mg quercetin equivalents per g of dry weight and 718.6 mg gallic acid equivalents per g of dry weight. The evaluation of antioxidant activities highlighted that the ethyl acetate extract of exocarp was the most active element. The study of the AChE inhibitory power demonstrated that the ethyl acetate extract of the exocarp had the greatest inhibitory activity. The ethyl acetate extract from the exocarp ameliorated cognitive performance and reversed the oxidative damage as compared to galactose group. Conclusion: M. pomifera fruit is a good source of natural antioxidants, which might help prevent oxidative stress-related damage and memory impairment in such mental disorders as Alzheimer’s disease (AD).

Effects of Various Drying Methods on Physicochemical Characteristics, Flavonoids and Polyphenol Content, and Antioxidant Activities of Different Extracts from Morinda citrifolia Fruit

Introduction: M. citrifolia is known as a medical plant in Vietnam, named Noni, which contains numerous bioactive ingredients and applying good in functional food and pharmaceuticals. The notices on the change of physicochemical characteristics (color, pH, total solids, and titration acid), the content of flavonoids and polyphenol, and antioxidant activities (total, reducing power, and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical scavenging) of different extracts from Morinda citrifolia fruit at various drying methods (solar energy, microwave, and heat pump), microwave power, and temperature have not been found. Therefore, the paper focused on these things.
 Methods: Morinda citrifolia fruit were harvested in July 2020, dried by using different methods (solar energy, microwave, and heat pump), and soaked in 96% solvent (ethanol and aqueous) for evaluating physicochemical characteristics, flavonoids and polyphenol content, and antioxidant activities. Drying M. citrifolia was at the temperature (50, 60, and 70°C) and the microwave power (100, 200, 400, 600, and 800 W), corresponding to the heat pump method and the microwave method, respectively and evaluating the drying speed curve basing on the moisture of M. citrifolia according to the drying time.
 Results: Physicochemical characteristics, flavonoids content, polyphenol content, and antioxidant activities (total, reducing power, and DPPH free radical scavenging) were affected by various drying methods, different extracting solvents (p<0.05) and changed the drying time, microwave power, and temperature according to the non-linear model of level 2. The stabilization of physicochemical characteristics, flavonoids content, polyphenol content, and antioxidant activities of M. citrifolia in the drying method of microwave power was the highest, followed by the heat pump and solar energy. Ethanol solvent was more effective than aqueous solvent as extracting bioactive substances (flavonoids content and polyphenol content).
 Conclusion: The results will be useful for preparing the dried M. citrifolia to serve for the storage and the produce of M. citrifolia in functional food and pharmaceuticals.

In vitro and In vivo Anti-inflammatory Activity of the Extracts of Whole Plant Argyreia imbricata (Roth) Sant. & Patel

Plants of the genus Argyreia have ethnomedicinal importance, and several pharmacological activities are also reported. In this study, the anti-inflammatory activity of different extracts of Argyreia imbricata was evaluated by in vitro and in vivo methods. In both evaluations, standard, Diclofenac sodium was used for comparative evaluation. In this study, extraction of powdered whole plant material was done with different solvents viz., petroleum ether, chloroform, ethyl acetate and methanol by soxhelation. In vitro anti-inflammatory activity of all the prepared extracts was evaluated by stabilization of human red blood cell (HRBC) membrane in different temperature and tonicity conditions. Among the six different concentrations of four tested extracts, the ethyl acetate and methanol extracts (1000μg/ml) showed significant activity in the in vitro evaluation. They were selected for the in vivo evaluation on the paw oedema induced by carrageenan on Wistar albino rats. Two doses, 200mg.kg-1 and 400mg.kg-1 of the test extracts were subjected to evaluation. Both the tested extracts showed the activity, particularly, the methanol extract in the dose of 400mg.kg-1 showed significant activity. Results of this study strongly supported the anti-inflammatory activity of the tested extracts. Further, studies on toxicity, identification, isolation of the active constituents may give useful results.

Biological activity and phytochemical screening of different extracts of Sida cordata (Burm.F.) borssum root

In the present study was designed to evaluate antimicrobial, anthelminthic activity and phytochemical analysis of different extracts of Sida cordata (Burm. f.) borssum root rxtract was prepared using different solvents like chloroform, petroleum ether, ethylacetate, ethanol, and water (aqueous extract). By using agar well diffusion method, the antibiotic activity of different extract was evaluated and minimum inhibitory concentration (MIC) by 96 well resazurin based microtiter dilution the test organisms were Escherichia coli, Staphylococcus aureus, Lacto bacillus Pseudomonas aeroginosa, Candida albicans, Aspergillus niger. Among the different the extracts (ethanolic and aqueous) showed significant antimicrobial activity against Staphylococcus aureus, Escherichia coli, Lacto bacillus, Pseudomonas aeroginosa, Candida albicans and Aspergillus niger. Against S.aureus, aqueous extract showed better activity (20mm, MIC 0.187 mg/ml) followed by Ethanol extract (15mm with MIC 0.390 mg/ml), further the aqueous extract showed activity against Pseudomonas aeruginosa, (15mm, MIC 1.5 mg/ml) followed by Ethanol extract (12mm with MIC 0.375 mg/ml) and same was observed for Lactobacillus (19mm). In terms of anthelmintic activity against Pheretima posthuma (Indian earthworm) aqueous extract of the root exhibited significant activity in the concentration of 100mg/ml with 22.0 and 39 minutes for paralysis and death, respectively and that of standard drug Albendazole was 20 and 38.00 minutes. The aqueous extract showed significantly better effect comparable to standard and hence higher anthelmintic activity. Keywords: Sida cordata, Antimicrobial Resazurin, Anthelminthic, Pheretima posthuma.

Comparative Study of Total Phenolic Contents, Antioxidant and Antimicrobial Activities of Different Extracts of Corchorus olitorius L. Growing in North Cyprus

Objective: In this study, antimicrobial and antioxidant activities as well as total phenolic content of dried leaf extracts of Corchorus olitorius grown in North Cyprus were determined. Methods: The total phenolic content, antioxidant and antimicrobial activity of the extracts were determined using the Folin-Ciocalteu, DPPH free radical and broth dilution methods, respectively. The antimicrobial activity of the extracts was tested against eight different microorganisms (Bacillus subtilis ATCC 6037, Listeria monocytogenes Scott A, Enterococcus faecalis ATCC 29212, Staphylococcus aureus 6538P, Bacillus cereus No 8, Escherichia coli O157:H7 ATCC 43895, Escherichia coli ATCC 1103, Salmonella Typhimurium NRRL-B-4420). Results: The highest phenolic content was obtained from ethanol extract as 24.61 mg GAE/g. Water, ethanol and methanol extracts of C. olitorius were inhibited the DPPH radical by 17.50%, 87.10% and 86.00%, respectively. MIC values of ethanol and methanol extracts of C. olitorius against test cultures were varied between 50.00% and 6.25%, while no inhibitory effect was observed for water extract. The most susceptible microorganisms to methanol extract of the plant were L. monocytogenes Scott A, E. faecalis ATCC 29212 and B. subtilis ATCC 6037 (MIC value of 6.25%). Conclusion: All these results showed that C. olitorius extracts are important sources showing antimicrobial and antioxidant properties.

EVALUATION OF ANTIOXIDANT ACTIVITY OF DIFFERENT EXTRACTS OF MEDICINAL PLANTS

Objective: The present study was carried out to evaluate the antioxidant activity of different extracts of two medicinal plants.
 Methods: In-vitro antioxidant activity of different extracts of Hydrocotyle javanica Thunb and Peristrophe bicalyculata (Retz.) Nees were determined by following methods such as Lipid peroxide assay (LPO), nitric oxide assay (NO), glutathione (GSH), catalase (CAT).
 Results: Among eight different extracts, n-Hexane H. javanica extract and alcoholic P. bicalyculata extract showed more potent in vitro antioxidant activity in terms of LPO, NO, GSH, SOD, and CAT assay.
 Conclusion: From the results, it can be concluded that n-Hexane H. javanica extract and alcoholic P. bicalyculata extract showed more potent in vitro antioxidant activity.

The antibacterial activity of different extracts from two Lebanese indigenous plants: Stachys ehrenbergii and Calamintha origanifolia

The antibacterial activity of different extracts from two Lebanese indigenous plants: Stachys ehrenbergii and Calamintha origanifolia

Preliminary phytochemical analysis and antibacterial study of crude extract from Hamelia patens stems

The present study aimed to analyse the phytochemical and antibacterial activity of different extracts of the tropical plant Hamelia patens Jacq. (Rubiaceae). The antimicrobial activity was carried out using agar well diffusion method. Hexane, petroleum ether, ethanol and chloroform stem extracts (100 μL of 50 mg/mL each) were introduced into the wells separately and allowed it to undergo incubation. After the incubation time was over, the plates were observed for zones of inhibition and compared with positive control ciprofloxacin at a concentration of 30 μM. These results provided evidence that the tested plant extracts possess antimicrobial properties which can be tested further in the development of novel antimicrobial agents.

Phytochemical screening, FTIR spectral analysis, antioxidant and antibacterial activity of leaf extract of Pimenta dioica Linn

Pimenta dioica (L.) (Allspice) is commonly known as Jamaica pepper, belongs to the family Myrtaceae. The present work was aimed to determine the phytochemical screening analysis, antioxidant activity and antimicrobial activity of different extracts of Pimenta dioica leaves. Phytochemical screening indicates the presence of carbohydrate, protein, steroid, alkaloid, flavonoids, phenol and terpenoids in ethanolic extract; protein, phenol and terpenoids were present in diethyl ether extract; whereas carbohydrate, alkaloid, flavonoids, steroids, saponins, tannin and terpenoids present in aqueous extract. The antioxidant content of the P. dioica leaf extract was evaluated by ferrous ion chealating assay, nitric oxide radical scavenging assay and DPPH test. The antioxidant activity was found to be increased with increasing concentration of ethanol extract. The functional groups present in Pimenta dioica leaves was analysed which indicate the presence of carboxylic acid, alkyl halides alkanes and misc. In antibacterial activity, maximum zone of inhibition was observed in aqueous extract against K. pneumonia, S. aureus and S. mutans; ethanolic extract confirmed a strong antibacterial activity against S. aureus and B. subtilis . The presence of antioxidant properties and antimicrobial effects of P. dioica suggests that it can be used against the human pathogenic bacteria and for other disease management and rejuvenation immunity support.

Chemical profiling and in vitro antioxidant, antibacterial and anticholinesterase activities of an endemic North African species Bellevalia mauritanica Pomel

Abstract The aim of this study was to evaluate antioxidant, antibacterial, and anticholinesterase activities of different extracts of an uninvestigated endemic species Bellevalia mauritanica Pomel, and identification of its phenolic and flavonoid content by a comprehensive and validated LC-MS/MS method using 37 phytochemical standards. Moreover, the phytochemical profiling of the studied extracts was accomplished by LC-MS-IT-TOF technique. Among all the tested extracts, ethyl acetate (EtOAc) of BRCE (bulbs-roots crude extract) was the most active one. It exhibited a medium antibacterial activity, good inhibition of acetylcholinesterase and a good antioxidant activity in ABTS•+ (2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonique), DPPH• (1,1’-diphenyl-2-picrylhydrazyl radical), and superoxyde DMSO (dimethyl sulfoxide) alkaline scavenging assays. LC-MS/MS analysis revealed that EtOAc extract had caffeic acid (1240.7 µg/g extract) and chloroform extract had vanillin (2048.5 µg/g extract) in considerable amounts. They also contained good amounts of certain phytochemicals such as protocatechuic acid (274.3 and 145.2 µg/g extract), p-coumaric acid (382.8 and 310.9 µg/g extract), ferulic acid (361.2 and 969.4 µg/g extract) and kaempferol (146.7 and 150.6 µg/g extract) respectively. LC-MS-IT-TOF screening revealed the presence of 91 major phytochemicals in the three extracts derived from bulb-roots crude extract.

Platelet Anti-Aggregant Activity and Bioactive Compounds of Ultrasound-Assisted Extracts from Whole and Seedless Tomato Pomace

Tomato paste production generates a residue known as tomato pomace, which corresponds to peels and seeds separated during tomato processing. Currently, there is an opportunity to use tomato pomace to obtain a functional extract with antithrombotic properties, such as platelet anti-aggregant activity. The aim of this study was to evaluate the yield and inhibitory activity of different extracts of tomato pomace on in vitro platelet aggregation, comparing this activity with commercial cardioprotective products, and quantify bioactive compounds. Aqueous or ethanolic/water (1:1) extracts of whole tomato pomace, seedless tomato pomace, tomato pomace supplemented with seeds (50% and 20%), and only seeds were obtained with different ultrasound-assisted extraction times. The inhibition of platelet aggregation was evaluated using a lumi-aggregometer. The quantification of bioactive compounds was determined by HPLC-MS. From 5 g of each type of tomato pomace sample, 0.023–0.22 g of a dry extract was obtained for the platelet aggregation assay. The time of sonication and extraction solvent had a significant role in platelet anti-aggregant activity of some extracts respect the control. Thus, the most active extracts decreased adenosine diphosphate (ADP)-induced platelet aggregation from 87 ± 6% (control) to values between 26 ± 6% and 34 ± 2% (p < 0.05). Furthermore, different ultrasound-assisted extraction conditions of tomato pomace fractions had varied concentration of flavonoids and nucleosides, and had an effect on extract yield.

Anticancer, antioxidant, and hepatoprotective activity of Saussurea lappa, C.B. clarke (qust) on human hepatoma cell line.

Liver cancer is considered as one of the most widespread malignancies across the globe. According to a recent estimate, about 782,000 people were diagnosed with liver cancer, out of which 746,000 people died. Conventional anticancer therapy cannot fulfill all the clinical needs due to accessibility, clinical efficacy, and safety issues. Hence, the need of novel inexpensive drugs from traditional medicine as potential chemotherapeutic agent becomes utmost urgent. Root of Saussurea lappa, C.B. Clarke (Unani name, qust) has been used in the Unani medicine for the treatment of chronic liver diseases (warm-e-jigar sulb) including hepatocellular carcinoma since centuries. The objective is to study the anti-cancerous, antioxidant, and hepatoprotective activity of different extracts of SLE in vitro. MTT assay was used to determine the anticancer activity and EC50 of SLEs. Cell viability and cell inhibition were calculated. Apoptosis was studied by DAPI 4',6-diamidino-2-phenylindole (DAPI) staining. Thein vitro hepatotoxicity of CCl4 was produced and hepatoprotective properties of different concentrations of ethanolic (ESL), aqueous (ASL), and hydroethanolic extract of Saussurea lappa (HSL) have been evaluated by measuring cell viability in HepG2 cells. MTT assay revealed that the molecule reduced the cell viability of HepG2 cancer cells. Test drugs induced apoptosis in a concentration-dependent manner, as indicated by DAPI staining. In addition, ESL, ASL, and HSL also reduced the colony-forming potential of the HepG2 cell. ESL, ASL, and HSL were observed to protect the HepG2 cells from CCl4 induced injury in a dose-dependent manner. The observed effect substantiated the anti-cancerous, antioxidant, and hepatoprotective activity of SLEs in HepG2 Cells.

Evaluation of the biological and wound healing activities of Centaurea virgata

Objective: Plants have significant potential effects in treating the wound. The vast majority of plants are used by the public in the treatment of wounds. The aim of this study was to investigate the antioxidant and in vitro wound healing activities of Centaurea virgata (C. Virgata).&#x0D; Methods: The antioxidant activities of extracts were examined by 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and ABTS methods. The amount of total phenolic was determined using the Folin-Ciocalteu reagent (FCR) method. In addition, the antiproliferative activity of different extracts on fibroblast cells were performed by MTT method and in vitro wound healing activity of ethanol extract of C. Virgata was determined by scratch assay. &#x0D; Results: Ethyl acetate extract of C. virgata (CVEA) had the highest DPPH radical scavenging activity with a IC50 value of 138.7 μg/mL. On the other hand, hexane (CVH) and aqueous ethanol (CVAE) revealed a very poor antioxidant activity with a IC50 values of 824,8 µg/mL and 610,3 ± 12,8 µg/mL, respectively. According to ABTS results, it was determined that the CVEA extract had stronger radical scavenging activity than the other extracts. On the other hand, among all of the extracts analysed, it was found that phenolic contents of CVEA extract had higher than other extracts. Except for CVAE extract, other extracts showed antiproliferative activity depending on the dose. &#x0D; Conclusion: According to the obtained results, our finding suggests that CVAE extract has a migratory effect on fibroblasts and that CVAE might be a potential therapeutic agent for wound healing.

Fatty acid analysis, cytotoxicity, antimicrobial and antioxidant activities of different extracts of the flowers of Nyctanthes arbor-tristis L.

The fatty acid analysis and biological activity of n-hexane, dichloromethane, ethyl acetate and methanol extracts of Nyctanthes arbor-tristis L. flowers are reported. Five fatty acids namely palmitic (44.15%), stearic (19.34%), arachidic (15.06%), behenic (9.77%) and lignoceric (11.69%) acids were identified. From cytotoxicity test, the LC50 values (the median lethal concentration) for n-hexane, dichloromethane, ethyl acetate and methanol extracts as well as for standard vincristine sulphate were found 7.05, 4.67, 3.14, 5.53 and 0.50 μg/ml, respectively. Antibacterial activity results of different extracts were compared with standard antibiotic ciprofloxacin and tetracycline by measuring the zone of inhibition diameter in millimeter. The dichloromethane and ethyl acetate extracts showed significant antibacterial activity. From antioxidant activity test, IC50 values (50% inhibitory concentration) of n-hexane, dichloromethane, ethyl acetate, methanol extracts and ascorbic acid were found to be 291.92 mg/ml, 45.74 μg/ml, 21.86 μg/ml, 64.30 μg/ml and 3.98 μg/ml, respectively.&#x0D; Bangladesh J. Sci. Ind. Res.55(3), 207-214, 2020

Bioassay-guided isolation and antiproliferative efficacy of extract loaded in chitosan nanoparticles and LC-QTOF-MS/MS analysis of Achillea magnifica

This study investigated the antioxidant, anti-urease, anticholinesterase, and antiproliferative activities of different extracts of A. magnifica. The active compounds were isolated from chloroform extract, which has the strongest antiproliferative and antioxidant activities. The structures of the isolated compounds (elenolic acid, luteolin, eupatilin) were examined using spectroscopic techniques (NMR, UV, HR-MS). The antioxidant and antiproliferative effects of isolated compounds showed lower biological activity than those of the chloroform extract. Therefore, chitosan nanoparticles were prepared with this extract and characterized. The cytotoxic activities of the chitosan nanoparticles were examined, and they were found to have a strong antiproliferative activity similar to that of the chloroform extract. The ethanol extract had strong anti-urease and anticholinesterase activity compared with other extracts. Therefore, phenolic compounds that might be responsible for the biological activity were analysed by LC-QTOF-MS/MS. The ferulic acid derivative, apigenin-6-C-pentoside-8-C-hexoside, apigenin 6,8-di C-hexoside, vitexin, and diosmetin 8-C-glucoside (orientin 4′-methyl ether) compounds from this plant were analysed for the first time. The results showed that the chloroform-loaded chitosan nanoparticles had a strong antiproliferative activity in breast cancer cell lines (MCF-7, MDA-MB-231) and no toxic effect on normal cell lines (L-929), which suggested that this extract might be a potential candidate as a herbal medicine that can be investigated and evaluated in future cancer studies. Additionally, the potential use of ethanol extract as an anti-urease and anticholinesterase agent was revealed.

Cytotoxic Activity-Guided Isolation from Achillea monocephala, and Biological Activities of its Different Extracts

Background: The genus Achillea is one of the most important genus of the Asteraceae family and many species of Achillea are used in traditional medicine to treat several ailments. Aim: The aim of the current research was to evaluate in vitro cytotoxic activities of n-hexan, chloroform, ethyl acetate and methanol extracts and to isolate the active compounds from the extract showing the strongest cytotoxic activity. In addition to this, it was aimed to evaluate the biological activities (cytotoxic, antioxidant, anti-urease, anticholinesterase, antimicrobial) of different extracts and active compounds from Achillea monocephala. Methods and Materials: The in vitro antioxidant, cytotoxic, anti-urease, anticholinesterase and antimicrobial activities of different extracts from A. monocephala aerial parts were examined. The structures of the active compounds were determined by NMR techniques, UV, IR and LC-MS/MS analysis and their biological potential was examined. Results: The chloroform extract showed strong and selective cytotoxic activity on the cancer cell lines (MDA-MB-231, MCF-7). Besides, this extract exhibited stronger antimicrobial activity than other extracts. Therefore, through activity-guided procedures, luteolin, naringenin and 8-hydroxy-salvigenin compounds were isolated from this extract. The methanol extract showed stronger antioxidant (DPPH, ABTS, CUPRAC) and anticholinesterase activity than other extracts. The n-hexan extract exhibited the highest anti-urease activity. In this study, it was determined that the isolated compounds had a strong biological activity. Naringenin compound had stronger ABTS radical cation scavenging and ferric reducing/antioxidant power, cytotoxic and antimicrobial activity than other compounds. 8-hydroxy-salvigenin compound showed the highest urease and acetylcholinestease enzyme inhibition. Conclusion: The results of this study suggest that the extracts and isolated compounds from the A. monocephala may be used as antioxidant, cytotoxic, anti-urease, anticholinesterase and antimicrobial agents in the future.

STUDY OF ANTIBACTERIAL AND ANTIOXIDANT ACTIVITIES OF SAXICOLOUS LICHEN $ \textit{XANTHOPARMELIA STENOPHYLLA} $

Antibacterial and antioxidant activities of different extracts of saxicolous lichen Xanthoparmelia stenophylla sampled from Norashen, Gegharkunik Province of Armenia were studied. Methanol, ethanol and acetone extracts of lichen thalli were demonstrated to have activity against only tested gram-positive bacteria. Methanol extract of the lichen showed the highest amount of DPPH radical scavenging activity (~68%). Our studies did not reveal any significant antibacterial and antioxidant activities of aqueous extract.

Pharmacological Modeling and Study for Antidiabetic Activity of Praecitrullus fistulosus Leaves Extracts

Phytochemical and pharmacological investigations of leaves of Praecitrullus fistulosus for the antidiabetic activity have been done in our research work encompassed in depth and systematic screening of plant leaves and further extraction, characterization and bioevaluation. The research was envisaged for antidiabetic activity of different extracts procured by successive extraction methods and to find out or isolate the most possible active compounds from the active extracts showing the best activity. The antidiabetic activity of all extracts has been evaluated by STZ induced diabetes. The isolated compounds have been evaluated by in-vitro and in-vivo models. The alcohol soluble extractives values were found to be higher than water soluble extractive value. Alcohol being a moderately non polar solvent, able to extract polar and non-polar components yields higher extractive value. The ethanol extract shows significant enhancement in glucose tolerance in glucose fed hyperglycemic normal rats and produced a marked decrease in blood glucose levels at 200 mg/kg and 400 mg/kg body weight in streptozotocin-diabetic rats after 21 days treatment.&#x0D; Keywords: Praecitrullus fistulosus, Streptozotocin and Glibenclamide, diabetes, Pharmacological Evaluation

Secondary metabolites, phytochemical characterization and antioxidant activities of different extracts of Sideritis congesta P.H. Davis et Hub.-Mor.

Sideritis congesta, an endemic plant to Turkey, is extensively consumed as energizing herbal tea and used as a remedy in folk medicine. This study was designed to comparatively evaluate the phytochemical composition and antioxidant potentials of different extracts (methanol, infusion) and fractions (chloroform, ethyl acetate, and remaining water) of S. congesta. Antioxidant potentials of the samples were evaluated by DPPH radical scavenging, FRAP, CUPRAC, and total antioxidant capacity tests. Total phenolic, phenolic acid, and flavonoid contents were also evaluated spectrophotometrically. Moreover, presence of twenty-two phenolic metabolites were affirmed by using LC-MS/MS in MRM scan mode and then the quantification of verbascoside, martynoside, and leucoseptoside A was performed by using HPTLC densitometry. EtOAc fraction contained the highest phenolic content and the antioxidant activity, as well as the highest verbascoside and martynoside contents followed by R-H2O fraction. Phytochemical studies on R-H2O fraction, yielded seven compounds, including a phenylethanoid glycoside, verbascoside (1), two flavonoids, stachyspinoside (2), isoscutellarein 7-O-(6‴-O-acetyl)-β-allopyranosyl-(1 → 2)-β-glucopyranoside (3), a phenolic acid chlorogenic acid (4), an iridoid glycoside ajugoside (5), and a monoterpenoid glucoside mixture betulalbuside A (6) and 1-hydroxylinaloyl 6-O-β-D-glucopyranoside (7). The molecular structures of the isolated compounds were determined by NMR and MS experiments. This is the first phytochemical study on the polar constituent of S. congesta and the first report of the isolation of compounds 2, 6 and 7 from the genus Sideritis L.

Phytochemical Evaluation, Antioxidant and Antimicrobial Activities of Various Extracts from Leaves and Stems of Bryophyllum pinnatum

Antioxidant and antimicrobial activities of different extracts (methanol and ethyl acetate) of leaf and stem of Bryophyllum pinnatum were studied. The screening for the secondary metabolites was carried out using the standard methods. The antioxidant capacities of the different extracts were assessed using DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and Ferric reducing antioxidant power (FRAP) while the antimicrobial activity of the extracts obtained were screened against Gram-positive, Gram-negative bacteria and fungi (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa Salmonella spp., Vibrio cholerae, Candida albicans and Aspergillus niger) using Agar well diffusion method. Both extracts obtained from leaf and stem of Bryophyllum pinnatum contained most of the phytochemical compounds tested for. However, anthocyanins and anthraquinone were not detected in leaf extracts while coumarin was absent in stem extracts. Quantification of bioactive compounds showed that both extracts contained the highest concentration of polyphenols (34.49 ±0.47 mg GAE/g and 32.32 ±1.2 mg GAE/g for methanol leaf and stem extracts respectively) while the least concentration was recorded for alkaloids (0.03±0.02 mg/g for methanol stem extract). Results revealed that the extracts showed dose-dependent scavenging of DPPH as well as the ability of the extracts to reduce FeCl3 solution, with methanol extracts exhibiting the highest scavenging and reducing capacity. However the leaves of Bryophyllum pinnatum had greater antioxidant activity than the stem by DPPH and ferric reducing assays, with IC50 values ranging from 3.147µg/ml to 3.80µg/ml for DPPH and 331.9 - 451 µg/ml for FRAP assays. The antimicrobial activity of various solvent extracts of leaf and stem reveal that microorganisms exhibited different sensitivities towards these extracts in a dose-dependent manner. Methanol leaf extract showed no activity against Escherichia coli while Pseudomonas aeruginosa was insensitive to ethyl acetate leaf extract. For stem extracts, Aspergillus niger, Vibrio cholerae and Pseudomonas aeruginosa were resistant to methanol extract while Aspergillus niger, Salmonella spp. and Pseudomonas aeruginosa was resistant towards ethyl acetate stem extract. The results obtained in this study showed that Bryophyllum pinnatum is a reservoir of bioactive compounds and both extracts exhibited significant antimicrobial and antioxidant activity.