Metal Chelating Assays Research Articles

Antioxidant Activities and Identification of an Active Compound from Rambutan (<i>Nephelium lappaceum</i> L.) Peel

The consumption of rambutan fruit resulted in a vast amount of peels and seeds waste. Therefore, the exploration of active compounds having beneficial effects on human health, such as antioxidants, is very lucrative. This research was aimed to isolate and to identify the active compound as an antioxidant from rambutan peel. The powdered rambutan peel was extracted with a maceration technique using methanol then fractionated using petroleum ether, chloroform, and ethyl acetate to get the corresponding fractions. The extract and fractions were determined for its antioxidant activities in vitro using 2,2’-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and metal-chelating assay. The ethyl acetate fraction exhibited the highest antiradical activity with an IC50 value of 26.22 μg/mL and metal-chelating activity, accounting for 12.32%. The antioxidant activities of extract and fractions correlated with its phenolics and flavonoid contents. Identification of active compounds using FTIR, GC-MS, and NMR resulted in the chemical formula of C7H6O4, identified as 3,4-dihydroxybenzoic acid.

Biosynthesis of gold nanoparticles using marine microbe (Vibrio alginolyticus) and its anticancer and antioxidant analysis

The applications of green synthesised gold nanoparticles for the biomedical field are the most prominent and developing area in this modern era. In this present investigation, marine bacteria, Vibrio alginolyticus was used for the biosynthesis of gold nanoparticles. The biosynthesized gold nanoparticles (AuNps) were characterized by various spectroscopic analysis. The morphological analysis of AuNps was done through scanning electron microscope (SEM) and transmission electron microscope (TEM) respectively. The obtained size was estimated around 100–150 nm. The synthesized AuNps confirmed by its surface plasmon resonance peak (SPR) range using UV–Vis spectrophotometer. The bio-metabolites from marine bacteria which was responsible for the nanoparticles synthesis were analyzed using fourier transform infrared spectrophotometer (FT-IR). The biomedical application of synthesized eco-friendly AuNps analysed by different method such as, the antioxidant property and free radical scavenging activity through DPPH (1, 1- diphenyl 2-picrylhyorazyl) and metal chelating assay. The anticancer activity of colon carcinoma was confirmed through MTT assay while the apoptotic mediated cell death observed through the fluorescence analysis. The biosynthesized AuNPs showed a dose dependent inhibitory effect on the growth of colon cancer cells. The IC50 was 15 µg/ mL, and the maximum inhibition of the cell death was (>75%) obtained when treating 25 µg/mL. The apoptotic mediated cell death observed through nuclear condensation of the treated cells. The green synthesis of AuNPs emphases - to be cost effective and environmental friendly with anti-inflammatory and anti-cancer effects against colon cancer.

Chemical profile and biological properties of the endemic Turkish species Phyllocara aucheri

• Phytochemical analysis of the endemic Turkish species Phyllocara aucheri . • Phenolic derivatives & pyrrolizidine alkaloids through LC-MS. • Strong antioxidant activity related with the rich phenolic profile. • Promising neuroprotective and antidiabetic activity through in vitro tests. The aim of the present study is the phytochemical analysis of the aerial parts of Phyllocara aucheri (Boraginaceae), which is an endemic plant of Turkey. The phytochemical profile of the studied species was determined through LC-MS method. Sixteen secondary metabolites were identified, among which thirteen phenolic constituents, such as quercetin and kaempferol glycosides and caffeic acid derivatives, as well as three pyrrolizidine alkaloids (PAs) in the form of bases and N-oxides (PANOs) (europine, heliotrine and heliotrine N-oxide). The methanol extract of the aerial parts was assayed for its antioxidant properties, using free radical scavenging (DPPH • , ABTS •+ ), reducing power (FRAP, CUPRAC), phosphomolybdenum and metal chelating assays, while it has been also evaluated for in vitro enzyme inhibition against cholinesterases, α-amylase and α-glucosidase, exhibiting an interesting biological profile.

Quality Characteristics of Breast and Thigh Chicken Meat from Free- Range System: Comparative Antioxidant Profile of Indigenous and Improved Germplasm

Background: New chicken breeds are being evolved for backyard rural poultry production to overcome the slow growth, late sexual maturity and poor production of indigenous breeds. However, autochthonous poultry is epitomized for quality attributes of their products. With this in mind, the present study for the first time explored the antioxidant capacity of meat obtained from a unique Indian chicken, Kadaknath and a synthetic breed of poultry, Jabalpur colour (JBC). Methods: During the period 2018-2020, breast and thigh meat were collected from chickens (n=20/ group) at their commercial slaughter age (20 weeks). Meat extract was used for qualitative evaluation. Antioxidant activity was explored using five well established in vitro methods testing for different antioxidant mechanisms. Result: Both, Kadaknath and JBC meat was proteinaceous with higher protein concentration (g/100 g of wet weight) in the breast (Kadaknath, 25.21±0.31 and JBC, 25.65±0.39) than the thigh (Kadaknath, 19.98±0.29 and JBC, 19.04±0.23). Both the groups exhibited antioxidant capacity in all the assays. They showed good radical scavenging for ABTS and DPPH free radicals. Superiority of Kadaknath meat was ascertained unequivocally by the three assays viz. Ferric reducing antioxidant power (FRAP), lipid oxidation inhibition (TBARS) and metal chelating capacity. FRAP values (mM Fe2+/g of tissue) were 26.97±0.37 and 33.85±0.47 (Kadaknath) and 22.84±0.25 and 26.82±0.36 (JBC) for breast and thigh, respectively. Similarly, Kadaknath meat was more potent (% inhibition) iron chelator (breast, 62.71±0.99 and thigh, 75.07±0.98) in comparison to the JBC (breast, 46.30±2.36 and thigh, 63.12±1.87). Breast meat had better scavenging capacity than the thigh except in FRAP and metal chelating assays. Results provide insight into the antioxidant potential of backyard poultry germplasm thus, laying foundation for developing marketing strategies targeting consumers interested in nutritional quality, animal welfare and environmental sustainability. Furthermore, baseline data has been generated for studying medicinal properties attributed to the black chicken meat of Kadaknath.

Evaluation of antioxidant and antidepressant activity of hydro-alcoholic extract of Ximenia americana stem bark

The present study was undertaken to evaluate the antioxidant and antidepressant activity of hydroalcoholic extract of Ximenia americana in case of Sodium fluoride induced toxicity on ICR mices. Antioxidant activity of the plant was evaluated in vitro through 2,2’-Azobis (2-Amidino-propane) Dihydrochloride test, metal chelating assay and total antioxidant capacity and in vivo through evaluation of malondialdehyde content in brain and liver. Antidepressant activity was evaluated through tail suspension test. In vitro evaluation of antioxidant activity showed that hydro-alcoholic extract of stem bark of Ximenia americana possesses a total antioxidant capacity of 303.081 ± 4.946 mg equivalent ascorbic acid per gram. From 2, 2’-Azobis (2-Amidino-propane) Dihydrochloride and metal chelating tests, it emerged that the extract inhibits hemolysis and chelates metals concentration-dependent manner. Animals were randomly divided into four groups with five animals in each group. The control group received distilled water, group II received sodium fluoride at dose of 13.6 mg/kg body weight, group III and group VI: received respectively hydro-alcoholic extract of Ximenia americana at 250 mg/kg and 500 mg/kg with sodium fluoride during 7 days. Results showed sodium fluoride decrease animal’s body weight even at the presence of the extract, increased significantly animal’s inactivity time and malondialdehyde levels in liver and brain. Animal’s inactivity time and malondialdehyde levels were significantly improved at the presence of the hydro-alcoholic extract of Ximenia americana. Ximenia americana have potential to mitigate sodium fluoride toxicity.

Phytochemical screening and antioxidant activity of some medicinal plants’ crude juices

Leaves of fig, guava, olive and pomegranate and peels of ripe pomegranate fruits were mechanically pressed to obtain the crude juices. The resultant crude juices were subjected to the estimation of certain phytochemicals, i.e. total phenols, flavonoids, tannins and anthocyanins by HPLC. The assessment of their antioxidant activities were performed by three methods, i.e. DPPH, reducing power and metal chelating assays. The results indicated that the amounts of polyphenols, flavonoids, tannins and anthocyanins in crude pomegranate peels juices were markedly higher than those of other medicinal plants crude juices. The polyphenolic constituents in fig leaves, pomegranate leaves and peels, guava leaves and olive leaves were distinguished using HPLC. The major compounds found in all crude juices were gallic acid, ellagic acid, naringenin, ferulic acid and methyl gallate, respectively. Pomegranate peels crude juice exhibited the highest antioxidant activity assessed by the aforementioned methods in comparison with other medicinal plants crude juices.

Therapeutic propensities, phytochemical composition, and toxicological evaluation of Anagallis arvensis (L.): A wild edible medicinal food plant

Anagallis arvensis (L.) is a wild edible food plant that has been used in folklore as a natural remedy for treating common ailments. This study aimed to explore the biochemical properties and toxicity of methanol (MeOH) and dichloromethane (DCM) extracts of A. arvensis (aerial and root parts). Bioactive contents were assessed spectrophotometrically, and the secondary metabolites were identified by UHPLC-MS analysis. DPPH, ABTS, FRAP, CUPRAC, phosphomolybdenum, and metal chelating assays were employed to assess antioxidant activity. Inhibitory potential against key enzymes (α-glucosidase, urease, lipoxygenase (LOX), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE)) were also assessed. MTT assay was employed to test toxicity against SW-480, MDA-MB-231, CaSki, MCF-7, and DU-145 cancer cell lines. Methanolic extracts showed highest phenolic (aerial-MeOH: 27.5mg GAE/g extract; root-MeOH: 21.17mg GAE/g extract) and flavonoid (aerial-MeOH: 26.15mg QE/g extract; root-MeOH: 19.07mg QE/g extract) contents, and potent antioxidant activities. The aerial-MeOH extract was most potent for DPPH (IC50: 231 ug/mL), ABTS (131.12mg TE/g extract), FRAP (82.97mg TE/g extract), and CUPRAC (137.15mg TE/g extract) antioxidant assays. All extracts were cytotoxic towards tested cancer cells with IC50 values ranging from 12.57 to 294.5µg/mL and conferred a comparatively strong inhibition against α-glucosidase (aerial-DCM extract showed the highest inhibition against α-glucosidase with IC50 value of 20.97µg /mL), while aerial extracts were also considerably active against BChE (aerial-MeOH IC50: 224.63µg /mL), LOX (aerial-DCM IC50: 385.7µg /mL). Likewise, aerial-MeOH extract was most active against urease enzyme (IC50: 129.72µg /mL). UHPLC-MS investigation of methanolic extracts showed the existence of important phenolics, flavonoids, and saponins, including methyl gallte, quercetin, lanceoletin, and balanitesin, amongst others. Moreover, principal component analysis (PCA) highlighted the correlation amongst bioactive contents and observed biological activities. A. arvensis extracts could be regarded as a natural source of bioactive antioxidants, enzyme inhibitors and anticancer agents and can be further investigated as a lead source for food and pharmaceutical products. However, further studies to isolate, purify, and to characterize its bioactive phytochemicals are needed.

Proximate composition, polyphenols, and antioxidant activity of solid state fermented peanut press cake

The current research was led to assess the influence of solid-state fermentation (SSF) with Aspergillus oryzae (MTCC 3107) on polyphenols, antioxidant activities, and proximate composition from peanut press cake of variety HNG-10. Total phenolic, flavonoid, and tannin contents were calculated for polyphenols quantification whereas DPPH, ABTS, FRAP, and metal chelating assay were performed for antioxidant activity. Quantification of polyphenols was confirmed by High Performance Liquid Chromatography technique. Maximum value of total phenolic, flavonoid, and tannin content was found to be 25.55 µM/g GAE, 101.17 µM/g QE, and 245.33 µg/g TAE, respectively. The highest inhibition of free radicals scavenging was noticed on the 5th day of fermentation after that decreased gradually with the increase of fermentation time. Significant increase in fat, i.e. 7.05–12.80% and protein content i.e. 44.05–49.60% was observed. Significant difference in proximate composition of fermented and non-fermented press cake concluded that the progressive role of fermentation improved or transformed physico-chemical properties of substrates.

In vitro and in silico anti-oxidant, cytotoxicity and biological activities of Ficus benghalensis and Duranta repens

ObjectiveTo report in vitro anti-oxidant activity and cytotoxicity of hydroalcoholic extract of Ficus benghalensis (bark) and Duranta repens (whole plant), and present the probable biological spectrum of major anti-oxidants from both plants.MethodsThe coarse powder of both plants was first extracted with 70% ethanol (maceration) followed by 99% ethanol (Soxhlet-extraction). Anti-oxidant activity of the extracts was evaluated using DPPH, H2O2, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), NO scavenging assay, total antioxidant capacity, cupric reducing antioxidant capacity (CUPRAC), and metal chelating assay. Cytotoxicity of both extracts was evaluated using MTT assay in both tumor and normal cell lines i.e. Chinese hamster ovary cells (CHO) and A549 cells. Biological activity of individual anti-oxidants from both medicinal plants was identified using prediction of activity spectra for substances and a docking study was performed by using autodock4.0.ResultsHydroalcoholic extract of F. benghalensis and D. repens showed the highest free radical scavenging (ABTS) and chelating capacity respectively. Both extracts showed minimum cytotoxicity in normal cell lines compared to tumor cell lines. Computer imitation hits reflected the multiple biological activities agreeing with the folk use and some scientific reports. Further, we found the binding affinity of predicted anti-oxidant compounds with multiple protein molecules involved in oxidative stress.ConclusionThe present study reports the probable anti-oxidant mechanism for two folk agents and also presents probable pharmacological activities via computer simulations.

Chemical characterization and bio-pharmaceutical abilities of five different solvent extracts from aerial parts and roots of Scorzonera hispanica L.

• The biochemical properties of Scorzonera hispanica were investigated. • Liquid chromatography hyphenated with photodiode-array detection and tandem electrospray ionization mass spectrometry was used for chemical profiles. • Methanol and water extracts exhibited stronger abilities than other extracts. • Flavonoids and phenolic acids were the main compounds for aerial parts and roots, respectively. • The study could fill the gap of the scientific information lacking for S. hispanica . The genus Scorzonera contains important plants as traditional drugs and foods. In this sense, the aim of the present study was to determine the chemical composition, antioxidant activity and enzyme inhibitory effects of the root and aerial part of Scorzonera hispanica L. ( S. hispanica ) extracts. The antioxidant activities were evaluated using ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), metal chelating and phosphomolybdenum assays and the enzyme inhibitory properties were assessed against acetyl- (AChE) and butyryl-cholinesterase (BChE), tyrosinase, α-amylase and α-glucosidase. The results showed that the methanolic and ethyl acetate extracts possessed the highest phenol and flavonoid contents. The methanolic aerial part extract represented the highest antioxidant properties (FRAP: 58.41±1.55; CUPRAC: 126.18±0.94; DPPH: 47.92±0.07; ABTS: 71.69±0.03 mg Trolox equivalent (TE)/g) compared to the root extracts. The root extract significantly depressed AChE (2.64±0.02 mg galantamine equivalent (GALAE)/g), BChE (5.36±0.45 mg galantamine equivalent (GALAE)/g), tyrosinase (60.36±0.23 mg kojic acid equivalent (KAE)/g), α-amylase (0.61±0.01 mmol acarbose equivalent (ACAE)/g) and α-glucosidase (0.82±0.01 mmol acarbose equivalent (ACAE)/g) enzymes. Liquid chromatography hyphenated with photodiode-array detection and tandem electrospray ionization mass spectrometry (LC-DAD-MS n ) analysis revealed phytochemical fingerprint of the two part of the plant and the most abundant constituents were rutin and orientin for aerial parts, 3,5 and 4,5-dicaffeoyl quinic acids for roots respectively. This is the first report gathering scientific data on antioxidant, enzyme inhibitory activities and phytochemical composition of S. hispanica . Thus, this research can be used as one methodological starting point for further investigation on this plant.

Viscum album L. homogenizer-assisted and ultrasound-assisted extracts as potential sources of bioactive compounds.

Viscum album L. (Mistletoe) is one of the most famous plants in many countries utilized for several purposes. The current study aimed to describe chemical profiles and biological activities of homogenizer-assisted extract (HAE) and ultrasound-assisted extract (UAE)) of V. album parts (leaf, fruits, and seeds). Antioxidant (radical scavenging, reducing power, metal chelation, and phosphomolybdenum assays) and enzyme inhibitory properties (cholinesterases, amylase, glucosidase, and tyrosinase) were selected for biological evaluation. Chemical profiles were studied by HPLC-MS/MS and 32 compounds were identified in the extracts; caffeoylquinic acids and its derivatives, dimethylated flavonoids were the most significant compounds. Generally, the leaf extracts exhibited the best antioxidant and enzyme inhibitory effects in our tests. Multivariate analysis was performed to obtain more information for these data, then strong correlations between total bioactive compounds and tested parameters were observed. The present findings encourage us to further investigate V. album as a potential candidate for pharmaceutical and nutraceutical applications. PRACTICAL APPLICATIONS: Viscum album L. commonly called European mistletoe is a woody perennial shrub growing on coniferous trees with lathery leaves, small flowers, and white berries. It belongs to the Santalaceae R. Br. family from Europe and western/southern Asia. Traditional medicine recognizes mistletoe as a folk remedy to manage inflammation, hypertension, ulcers, and other diseases due to the presence of different bioactive compounds, among them mistletoe lectins and viscotoxins. Recent studies documented the possible therapeutic applications of Viscum extracts in association with cancer's therapy leading to improvements in health and patient's quality of life. Thus, this work gives novel data regarding the phytochemical characterizations and antioxidant/enzymatic inhibitor activities of different types of extracts from seeds, leaves, and fruits of Viscum L. obtained by homogenizer-assisted and ultrasound-assisted techniques, in order to increase the data set of potential applications in medicine.

Synthesis And Evaluation Of Herbal Formulation Using Natural Extract

Our study is intended to prepare and evaluate the polyherbal formulation (PHF) using Nyctanthes arbor-tristis, Piper nigrum, and lemon juice. Poly Herbal Formulation F1 and F2 were synthesised and subjected to qualitative, quantitative phytochemical analysis and antioxidant activity was measured using a standard protocol. Antimicrobial activity of PHFs was observed by the agar well diffusion method. The anti-inflammatory and anti-diabetic activities (In-vitro) were studied in F1 by using inhibition of albumin denaturation method. TLC and FTIR are done for the structural elucidation in F1. The F1 and F2 exhibited the presence of flavonoids, alkaloids, tannins, phenols, terpenoids, carbohydrates, saponins, Glycosides and proteins. The F1 and F2 show significant activity against the standard in the antimicrobial and antioxidant activity. The presence of flavonoids and alkaloids may contribute to the anti-microbial activity. The Nitric oxide radical scavenging activity and a metal chelating assay of the F1 possess the highest antioxidant activity of 73.1% and 69% respectively. TLC confirms the presence of flavonoids in F1. FTIR spectrum shows the functional group of amines, alcohols, nitrites, aromatic and aliphatic compounds. These FTIR bands denote stretching and vibrational bands responsible for the compounds like flavonoids, terpenoids, phenols and amino acids. This investigation shows the excellent result in antimicrobial, antioxidant and in-vitro anti-diabetic and anti-inflammatory activities. In future, the PHF of F1 can be used as potent therapeutical agents and can be further exploited for their other beneficial effect in the pharmacological studies.

Enzyme inhibitory, antioxidant, and antibacterial activities of ethanol fruit extract of Muntingia calabura Linn

Introduction: Muntingia calabura is used for many medicinal advantages. So far, limited study has been done for the bioactivities of M.calabura fruit. The study aimed to investigate the enzyme inhibitory, antioxidant, and antibacterial activities of M.calabura fruit. Methods: Ethanol extract of M.calabura fruit was tested for its inhibitory enzyme activities against key enzymes linked to human pathologies, such as diabetes (α-glucosidase and α-amylase), hyperuricemia (xanthine oxidase), and obesity (lipase). The antioxidant properties were investigated using different in vitro assays (DPPH, CUPRAC, reducing power, phosphomolybdenum, metal chelating and DNA-Damage protection assays). The fruit was also evaluated for its antibacterial activity against several gram positive and negative bacteria. Results: The total phenolic and flavonoid contents of the extract were 10.85 mgGAE/g and 3.30 mg QE/g, respectively. The fruit extract showed good inhibition against α-glucosidase and α-amylase (IC50 16.74 and 46.49 µg/ml, respectively), with activities stronger than acarbose (100.38 and 152.46 µg/ml, respectively). It exhibited weak inhibitory activity against xanthine oxidase (IC50 0.91 mg/ml) and lipase (IC50 16.48 mg/ml), weaker than the references used for respective test (IC50 allopurinol 5.31 µg/ml and orlistat 0.17 µg/ml). The extract showed antibacterial activities againts Chromobacterium violaceum, Staphylococcus aureus, Streptococcus mutans, Staphylococcus epidermidis, and Escherichia coli. The ethanol extract showed weaker antioxidant activities, when compared to ascorbic acid and BHT. However, the extract was able to protect DNA-damage. Conclusions: The study concludes that M. calabura fruit exhibits antioxidant, antibacterial, and enzyme inhibitory properties, thus can be a good source for pharmacological uses.

Phillyrea latifolia L. :Biological Properties Screening of Different Extracts

Phillyrea latifolia L. is widely used as astringent, diuretic and hypoglycaemic in Mediterranean traditional medicine. This work focused on the biological properties (antioxidant and enzyme inhibitory) of P. latifolia L. leaves extracts, obtained by different solvents (ethyl acetate, methanol and aqueous). The amount of phenolics and flavonoids in P. latifolia L. extracts was also assessed by spectrophotometric methods. The methanol extract showed the highest total flavonoid content (68.07 mg RE g-1). The ethyl acetate extract exhibited stronger DPPH radical scavenging activity (190.71 mg TE g-1). The best CUPRAC activity was shown by the methanol extract (609.38 mg TE g-1). The aqueous extract (14.83 mg EDTA g-1) displayed the highest activity in metal chelating assay. Results showed that ethyl acetate extract indicated the highest activity in enzyme inhibition tests. Considering the obtained data, P. latifolia L. has potential to be used as sources of natural antioxidant and enzyme inhibitor.

"Enzymatic and non-enzymatic antioxidant, anti-inflammatory and anticancer activities of Floscopa scandens Lour".

To explore the total phenolic and flavonoid content, enzymatic, non-enzymatic antioxidant properties, anti-inflammation and anticancer activities of hexane, ethyl acetate and methanol extracts of Floscopa scandens (F. scandens). Non-enzymatic antioxidant activity was examined by 2, 2-diphenyl-1-picrylhydrazyl assay, nitric oxide scavenging assay, hydroxyl radical scavenging assay, reducing power assay, hydrogen peroxide scavenging assay, superoxide scavenging assay and metal chelating assay. Enzymatic antioxidant ability was screened for the antioxidant enzymes such as ascorbate oxidase, peroxidase, catalase and polyphenol oxidase. The anti-inflammatory property was proved with the inhibition of protein denaturation and protease inhibitory assays. In vitro anticancer activity was assessed by cell viability assay. Methanol extract contained high amount of phenols (198.41 mg catechol equivalent/gram extract) and flavonoids (101.70 mg quercetin equivalent/gram extract) showed higher activity than hexane and ethyl acetate extracts in all experiments. Fresh plant showed considerable enzymatic antioxidant activity. The results revealed that the methanol extracts of F. scandens could be used as a potential source of antioxidant, anti-inflammatory and anticancer bioactive compounds.

Streptomyces sp. strain MUSC 5 from mangrove forest in Malaysia: Identification, antioxidant potential and chemical profiling of its methanolic extract

The present study explored the antioxidant potential of a Streptomyces sp. strain MUSC 5 from the mangrove forest soil in the Pahang State, Peninsular of Malaysia and determined the presence of biologically active chemical constituents contained in the methanolic extract. The 16S rRNA genomic DNA extraction, phylogenetic analysis and phenotypingmethods were used to confirm identity of strain. The antioxidant potential of methanolic extract from Streptomyces sp. strain MUSC 5 was assessed using a number of antioxidants assays which included free radical scavenging assays, metal chelation and ferric reduction antioxidant power (FRAP) assay. Furthermore, Gas chromatography Mass Spectrometry (GC-MS) was used to determine the presence of biologically active chemical compounds in methanolic extract of Streptomyces sp. strain MUSC 5. The strain was confirmed as belonging to Streptomyces genus. Antioxidant studies of the methanolic extractfrom Streptomyces sp. strain MUSC 5 revealed antioxidant activity of 24.97 ± 0.99 %, 22.95 ± 3.21% and 26.81 ± 1.05% against free radicals ABTS, DPPH and metal chelation, respectively. The result of FRAP assay was expressed in dose of 1-2 mg which was equivalent to 1.73- 2.15 microgram (μg) of ascorbic acid. GC-MS analysis carried out on the methanolic extract of Streptomyces sp. strain MUSC 5 detected the presence of 11 known compounds belonging to pyrrolopyrazine,esters, fatty acid esters, triterpene and an alkane group of compounds. The study supports the notion that Streptomyces from underexplored mangrove forest offer promising Streptomyces with antioxidant activity and could serve as important sources for new antioxidant agents.

Filago germanica (L.) Huds. bioactive constituents: Secondary metabolites fingerprinting and in vitro biological assays

Plants from Asteraceae have interesting medicinal potential in traditional medicines and have been studied for different pharmacological effects. This study attempts to describe the phytochemical and biological profiles of dichloromethane (DCM) and methanol (MeOH) extracts of aerial parts and roots of Filago germanica (L.) Huds. Phytochemical composition was assessed by high performance liquid chromatography photodiode array (HPLC-PDA) polyphenolic quantification, and ultra-high performance liquid chromatography mass spectrometry (UHPLC-MS) secondary metabolites analysis. Biological potential were determined via antioxidant (2, 2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid -ABTS, cupric reducing antioxidant capacity -CUPRAC and metal chelation), enzyme inhibition (α-amylase, tyrosinase and lipoxygenase -LOX) and cytotoxic (SW-480 colon cancer cell line) assays. The HPLC-PDA quantification identified 11 phenolic phytochemicals, amongst epicatechin (1.81 μg/g extract) and syringic acid (2.23 μg/g extract) were present in higher amounts. Similarly, UHPLC-MS analysis of both DCM extracts showed the tentative presence of several flavonoid, alkaloid and terpenoid derivatives as major components. The aerial-MeOH extract was found to possess highest ABTS and CUPRAC antioxidant potential with values of 119.11 and 170.83 mg Trolox equivalent (TE)/g extract, respectively. Root-DCM extract was the most active in the metal chelation assay (22.86 mg ethylenediaminetetraacetic acid equivalent (EDTAE)/g extract). The root-DCM extract was most active against tyrosinase (30.51 mg kojic acid equivalent (KAE)/g extract) and α-amylase (0.30 acarbose equivalent (ACAE)/g extract), while aerial-MeOH extract showed maximum LOX inhibition. Moreover, the aerial parts and root DCM extracts were most active against colon cancer cell line with half maximal inhibitory concentration (IC50) of 26.95 and 41.62 μg/mL, respectively. Based on the present findings, F. germanica can be viewed as a promising bio-resource for bioprospecting of novel pharmaceuticals and biomedicine industrial products.

In vitro α-amylase and α-glucosidase Inhibition, Antioxidant, Anti- Inflammatory Activity and GC-MS Profiling of Avicennia alba Blume.

Avicennia alba Blume, is a well-known mangrove plant used in traditional medicinal practices for several human ailments. The study aimed at the evaluation of antidiabetic, antioxidant, anti-inflammatory and cytotoxic activities of A. alba ethanolic leaf (AAL) and bark (AAB) extract along with phytochemical investigation. In vitro antidiabetic study was done by α-amylase, α-glucosidase enzyme inhibition assay; antioxidant study by DPPH, ABTS, superoxide, and metal chelating assays, antiinflammatory study by protein denaturation assay. The cytotoxicity study was done on TC1 murine cell line. Further, GC-MS analysis was carried out for AAL extracts. AAL exhibited better antidiabetic activities with IC50 values of 1.18 and 0.87 mg/ml against α-amylase and α-glucosidase enzymes respectively. The AAL exhibited better ABTS, superoxide scavenging and metal chelating potential with IC50 values of 0.095, 0.127 and 0.444 mg/ml. However, AAB showed higher DPPH scavenging potential with IC50 value of 0.163 mg/ml. The AAL also exhibited higher protein denaturation potential with IC50 value of 0.370 mg/ml. The bark extract exhibited better cytotoxic activity as compared to leaf extracts on the TC1 murine cell line. The phytochemical study revealed higher total phenol (25.64 mg GAE/g), flavonoid (205.09 mg QE/g), and tannin content (251.17 mg GAE/g) in AAL. The GC-MS analysis revealed the presence of several compounds in AAL extract. The result of the present study highlights the antidiabetic, antioxidant and cytotoxic activities of mangrove plant Avicennia alba.

Antibiofilm, antiquorum sensing and antioxidant activity of secondary metabolites from seeds of Annona senegalensis, Persoon

The increasing resistance of bacteria to antibiotics has motivated the interest in potent natural compounds capable of disrupting bacterial cell-to-cell communication. Column chromatography of seed extract of Annona senegalensis afforded N-cerotoyltryptamine (1), asimicin (2) and ent-19-carbomethoxykauran-17-oic acid (3). The compounds were tested for their antimicrobial, antibiofilm, and anti-quorum sensing activities. The minimum inhibitory concentrations (MIC) values ranged from 50μg/mL to 100μg/mL for C. albicans ATCC 10239 and S. aureus ATCC 25923 E. coli ATCC 25922, C. violaceum CV026 and C. violaceum CV12472. All the compounds inhibited biofilm formations of all microorganisms tested in various percentages at MIC and MIC/2. Compound 2 also exhibited the highest antibiofilm activity against C. albicans (yeast) and E. coli with percentage inhibitions ranging from 6.3±4.1 (MIC/4) to 37.9±4.5 (MIC) for C. albicans and from 18.8±1.1 (MIC/4) to 43.2±0.5 (MIC) for E. coli. Compound 1, however, showed highest biofilm inhibition on S. aureus as the percentage inhibition varied from 26.7±3.6 (MIC/4) to 43.8±2.1 (MIC). Compound 2 showed highest percentage violacein inhibition on C. violaceum CV12472 ranging from 10.2±0.5 (MIC/8), 65.76±1.3 (MIC/2) and 100 (MIC). Compound 1 and 3 had percentage violacein formation inhibitions on C. violaceum CV12472 ranging from 9.66±1.1 (MIC/4) to 100 (MIC), and from 17.4±2.4 (MIC/4) to 100 (MIC), respectively. Swimming and swarming motility of P. aeruginosa PA01 strain was evaluated at three concentrations of 50, 75 and 100μg/mL. The compounds inhibited the P. aeruginosa swimming and swarming motility at the three tested concentrations (50, 75 and 100μg/ml) in a dose-dependent manner. The extents of inhibition of motility migration was relatively higher in the swimming model than in the swarming model for all compounds. Compound 1 exhibited the highest percentage inhibition of motility of 41.50±3.5 and 39.73±1.5 in swimming model and swarming model respectively at 100μg/ml. Compound 3 showed the lowest percentage inhibition of 30.36±2.0 and 23.50±2.5 in swimming and swarming respectively at 100μg/ml. At the lowest tested concentration of 50μg/ml, it was compound 2 showing the highest inhibition of motility of 17.49±0.5 and 14.29±1.0 in swimming and swarming respectively. Compound 1 showed highest quorum sensing (QS) activity with QS inhibition zone of 20.0±1.5mmat MIC and 11.0±1.0mmat MIC/8 while compound 2 had the highest antimicrobial (AM) zone diameter amongst the compounds at MIC. Compound 3 was the QS inhibitory sample and did not show any QS inhibition at MIC/8 while showing its highest QS inhibition zone of 13.0±1.6mmat MIC. For antioxidant assays, no sample showed better activity than the standards. Compound 2 had highest activity with IC50 values of 87.79±2.70 and 42.77±1.53μg/mL in DPPH and β-carotene-linoleic acid assay respectively and was more active (IC50 of 97.69±1.40μg/mL) than standard quercetin (IC50 250.09±0.87μg/mL) in metal chelation assay.

In vitro and in silico approach to determine neuroprotective properties of iridoid glycosides from aerial parts of Scrophularia amplexicaulis by investigating their cholinesterase inhibition and anti-oxidant activities

Three iridoid glycosides included 6-O-methyl, 1-glucopyranosyl catalpol (Compound 1), 6-O-α-L (3"-O- trans, 4"-O- trans cinnamoyl)-rhamnopyranosyl catalpol (Compound 2) and scropolioside D (Compound 3) were isolated from aerial parts of S. amplexicaulis using chromatographic methods. The structures were determined by different spectroscopic data. The inhibitory effects (IC50 values) of the compounds on cholinesterase (AChE and BChE) was determined by in-vitro assays. Docking studied were performed to investigate receptor-ligands interactions. The antioxidant capacity was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, 2, 2'-azino-bis[3-ethylbenzothiazoline]-6-sulphonic acid (ABTS) radical cation, cupric ion reducing activity (CUPRAC), ferric reducing antioxidant power (FRAP), phosphomolybdenum and metal chelating assays. AChE and BChE were moderately inhibited by all of the investigated iridoid glycosides (compared to galantamine). Compound 2 and compound 3 showed comparable anti-oxidant effects with the Trolox as the control in phosphomolybdenum assay. Also, compound 1, showed acceptable activities in ABTS radical scavenging and Phosphomolybdenum assays compared to the control.