scholarly journals Isolation, characterization and evaluation of antioxidant activities of secondary metabolites producing actinomycetes of terrestrial origin

Author(s):  
Jessy Padma B. ◽  
Saraswathi K. ◽  
Arumugam P. ◽  
Anna Shiny R.

Background: Microbial secondary metabolites are important sources of natural compounds when compared to others with potential, beneficial therapeutic applications. There are chances of discovery of new Streptomyces species and new compounds from the respective genus. Due to ever and over increasing resistance of pathogenic bacteria to our current arsenal of antibiotics, a great need exists for the isolation and discovery of new antibiotics and other drug agents. Based on the above concept actinomycetes are mainly targeted for secondary metabolites production and evaluation of compounds therapeutically.Methods: Totally 15 pure isolates were obtained from two different soil samples by spread plate and quadrant streak techniques. Their colony and surface morphology were studied by morphological and biochemical characterization. Secondary metabolites were extracted by solvent extraction and the presence of bioactive compounds was detected by thin layer chromatography. The antioxidant potential was determined by Dot plot, DPPH and Phosphomolybdenum assay. The nature and the number of active compounds were identified by GC-MS analysis.Results: Among the 15 isolates, 10 isolates were found to have characteristic features of actinomycetes and 8 isolates were found to be fast growing actinomycetes. Among these 8 isolates, isolates of terrestrial origin were found to possess more bioactive compounds than those of marine origin and the four terrestrial isolates selected for evaluation of bioactive compounds and determination of antioxidant potential showed that the isolate TS 1010 had better and efficient secondary metabolite activity.Conclusions: Thus, from the above study it is seen that not only actinomycetes of marine origin, but terrestrial origin are also fast growers and possess better antioxidant and radical scavenging activity.

Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2742
Author(s):  
Mohammad-Zahirul Islam ◽  
Buem-Jun Park ◽  
Young-Tack Lee

Wheat and barley grasses are freshly sprouted leaves of wheat and barley seeds, and are rich sources of phytochemicals. This study was conducted to investigate the effects of day and night temperatures on the growth, bioactive compounds, and antioxidant potential of wheat and barley grasses. Briefly, each grass was cropped in an organic growing medium at 10/5 °C, 20/15 °C, and 30/25 °C (day/night temperature) in a growth chamber by maintaining specific light (12/12 h light/dark; light intensity 150 µmol photons m−2 s−1) and humidity (60%) conditions for 8 days. The highest growth parameters (height, weight, and yield) were observed at the 20/15 °C growth conditions in both types of grass. Conversely, the lowest growth parameters were observed at 10/5 °C. However, the low growth temperature of 10/5 °C resulted in increased levels of bioactive compounds (total phenol, total flavonoid, and total vitamin C), antioxidant activities (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid and 2,2-Diphenyl-1-picrylhydrazyl radical-scavenging activity)), and antioxidant enzymes (guaiacol peroxidase activity, catalase activity, and glutathione reductase) in both types of grass. Therefore, proper temperature growth conditions of wheat and barley grasses may be a convenient and efficient method to increase bioactive compounds and antioxidant potential in our diet to exploit the related health benefits.


2019 ◽  
Author(s):  
Chem Int

Oil extracted from Persea Americana seed was assayed for its physiochemical properties and antioxidant potential using various standard methods. The oil content of the seed was found to be < 10%. Brownish-red color oil was liquid at room temperature, with specific gravity of 0.91±0.02 g/mL. Other physiochemical parameters determined were; acid value (4.51±0.08 mgKOH/g), %FFA (2.26±0.08), peroxide value (2.40±0.57 mgO2/Kg), ester value (31.26±0.03 mgKOH/g), saponification value (35.76±0.07 mgKOH/g) and iodine value (23.5±0.07). The results of the antioxidant activities of the seed oil showed that the flavonoid content (80.00±1.41 mgQE/g) was ~10 folds higher than the phenolic content (8.27±0.06 mgGAE/g). The DPPH radical scavenging value was found to be 51.54±0.25% with an IC50 value of 4.68±0.02 mg/mL and reducing power with an average absorbance of 0.85±0.01 and an IC50 value of 0.001±0.02 mg/mL. Gallic acid showed better antioxidant activities than the oil studied. The results obtained in this study showed that Persea Americana seed oil has nutritional, industrial as well as medicinal potentials.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1718
Author(s):  
Kaimin Lu ◽  
Jing Zhou ◽  
Jie Deng ◽  
Yangjun Li ◽  
Chuanfang Wu ◽  
...  

The incidence and prevalence of inflammatory bowel disorders (IBD) are increasing around the world due to bacterial infection, abnormal immune response, etc. The conventional medicines for IBD treatment possess serious side effects. Periplaneta americana (P. americana), a traditional Chinese medicine, has been used to treat arthritis, fever, aches, inflammation, and other diseases. This study aimed to evaluate the anti-inflammatory effects of oligosaccharides from P. Americana (OPA) and its possible mechanisms in vivo. OPA were purified and biochemical characterization was analyzed by HPGPC, HPLC, FT-IR, and GC–MS. Acute colitis mice model was established, the acute toxicity and anti-inflammatory activity were tested in vivo. The results showed OPA with molecular mass of 1.0 kDa were composed of 83% glucose, 6% galactose, 11% xylose, and the backbone was (1→4)-Glcp. OPA had potent antioxidant activities in vitro and significantly alleviated the clinical symptoms of colitis, relieved colon damage without toxic side effects in vivo. OPA exhibited anti-inflammatory activity by regulating Th1/Th2, reducing oxidative stress, preserving intestinal barrier integrity, and inhibiting TLR4/MAPK/NF-κB pathway. Moreover, OPA protected gut by increasing microbial diversity and beneficial bacteria, and reducing pathogenic bacteria in feces. OPA might be the candidate of complementary and alternative medicines of IBD with low-cost and high safety.


2021 ◽  
Vol 28 ◽  
Author(s):  
Sreekala S. ◽  
Usha Devi Muraleedharan

Background: While several biologics have been reported from different parts of Clitoria ternatea, a herbaceous climber of the family Fabaceae, specific production of cationic peptides other than cyclotides (<3.7 kDa) has barely been investigated or their bioactive potential looked into. Objective: To uncover potential bioactivities and characteristics of novel cationic peptides from C. ternatea seeds. Methods: C. ternatea seed cationic peptide purified by simple and cost-effective procedures was analyzed by electrophoresis and mass spectrometry. Antimicrobial efficacy was evaluated against bacterial and fungal pathogens. Antioxidant potential was quantified by in vitro antioxidant assays. Physicochemical characterization and Tandem mass spectrometry were performed. Results: An 8.5 kDa cationic peptide purified from C. ternatea seeds was active against Candida albicans, Staphylococcus aureus, Aeromonas hydrophila and Escherichia coli at a minimum inhibitory concentration in the range of 8-32 μg/ml. This activity was totally uncompromised at pH 5-8 or after 1 h of heat treatment at 70-80 ºC, but was sensitive to protease treatment. Concentration-dependent free-radical scavenging activity and ferric-reducing capacity demonstrated the antioxidant potential of the peptide. Tandem MS analysis of trypsin-digested peptide based on shotgun proteomics detected matching peptide sequences with one or two cysteine residues but had low sequence coverage (≤17%) to known sequences in the C. ternatea protein database. Taken together, the distinct characteristics of this novel 8.5 kDa peptide clearly distinguishes it from known cyclotides of C. ternatea. Conclusions: Insights have been obtained into the functional characteristics of what appears to be a novel cationic peptide from C. ternatea seeds, exhibiting significant antimicrobial and antioxidant activities.


Antibiotics ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 270
Author(s):  
Ilhem Saadouli ◽  
Imène Zendah El Euch ◽  
Emna Trabelsi ◽  
Amor Mosbah ◽  
Alaeddine Redissi ◽  
...  

Streptomyces is the most frequently described genus of Actinomycetes, a producer of biologically active secondary metabolites. Indeed, the Streptomyces species produces about 70% of antibiotics and 60% of antifungal molecules used in agriculture. Our study was carried out with the goal of isolating and identifying antimicrobial secondary metabolites from Streptomyces misionensis V16R3Y1 isolated from the date palm rhizosphere (southern Tunisia). This strain presented a broad range of antifungal activity against Fusarium oxysporum, Aspergillus flavus, Penicillium expansum, Aspergillus niger, Candida albicans, Candida metapsilosis, and Candida parapsilosis and antibacterial activity against human pathogenic bacteria, including Escherichia fergusonii, Staphylococcus aureus, Salmonella enterica, Enterococcus faecalis, Bacillus cereus and Pseudomonas aeruginosa. The purification procedure entailed ethyl acetate extract, silica gel column, and thin layer chromatography. Based on 1H NMR metabolomic procedure application, also supported by the GC-MS analysis, cyclic dipeptide (l-Leucyl-l-Proline) was identified as the major compound in the bioactive fraction. In order to confirm the identity of the active compound and to have a large quantity thereof, a chemical synthesis of the cyclic dipeptide was performed. The synthetic compound was obtained with a very good yield (50%) and presented almost the same effect compared to the extracted fraction. This study indicates for the first time that Streptomyces misionensis V16R3Y1 exhibits a broad spectrum of antimicrobial activities, produced cyclic dipeptide (l-Leucyl-l-Proline) and might have potential use as a natural agent for pharmaceutical and agri-food applications.


2019 ◽  
Vol 48 (4) ◽  
pp. 1075-1081
Author(s):  
Hafiz Muhammad Waqas ◽  
Muhammad Akbar ◽  
Muhammad Sajjad Iqbal

In the present study, antibacterial and antioxidant (DPPH free radical scavenging activity) activity of an edible mushroom, Agaricus bisporus collected from Pakistan was investigated. In antibacterial assays, nhexane showed 4.83, 3.33, 16 and 3.33 mm inhibition zone diameter (IZD), chloroform showed 6.33, 16.17, 17 and 1.67 mm (IZD) while, ethyl acetate exhibited 30, 20, 19 and 28.67 mm (IZD) against four test plant pathogenic bacteria viz., Pseudomonas syringae Van Hall, Ralstonia solanacearum Yabuuchi et al. Xanthomonas axonopodis Dowson and Erwinia carotovora (Jones) Waldee, at 100 mg/ml concentration. Optical density (OD) was recorded at 517 nm. n-hexane extract showed 60.73, 47.6 and 33.05%, chloroform showed 89.97, 82.91 and 77.68% whereas, ethyl acetate exhibited 89.83, 65.82 and 23.59% free radical effects as compared to control. Gas chromatography mass spectrometry (GCMS) analysis showed the highest concentration of mono(2-ethylhexyl) phthalate.


2019 ◽  
Vol 79 (1) ◽  
pp. 127-132
Author(s):  
F. C. Pontes ◽  
V. C. P. Abdalla ◽  
M. Imatomi ◽  
L. F. G. Fuentes ◽  
S. C. J. Gualtieri

Abstract In recent years, natural products with antifungal and antioxidant activities are being increasingly researched for a more sustainable alternative to the chemicals currently used for the same purpose. The plant pathogenic fungus Alternaria alternata is a causative agent of diseases in citrus, leading to huge economic losses. Antioxidants are important for the production of medicines for various diseases that may be related to the presence of free radicals, such as cancer, and in the cosmetic industry as an anti-aging agent and the food industry as preservatives. This study evaluated the antifungal and antioxidant potential of extracts of mature leaves of Myrcia splendens, a tree species that occurs in the Brazilian Cerrado. The antioxidant potential was analyzed by an assay of 1,1-diphenyl-2-picrylhydrazyl radical-scavenging method, and the antifungal activity was assessed through the evaluation of mycelial growth. Majority of the extracts exhibited a strong antioxidant activity, especially the acetonic extract (4A). The antioxidant activity may be related to the presence of phenolic compounds. However, the extracts showed no inhibitory activity of mycelial growth of the fungus tested, with the exception of dichloromethanic extract (2B), which had an inhibitory effect (10.2%) at the end of testing.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Mayron Alves Vasconcelos ◽  
Francisco Vassiliepe Sousa Arruda ◽  
Daniel Barroso de Alencar ◽  
Silvana Saker-Sampaio ◽  
Maria Rose Jane Ribeiro Albuquerque ◽  
...  

This study evaluated the effect of derriobtusone A, a flavonoid isolated fromLonchocarpus obtusus, on two important pathogenic bacteria,Staphylococcus aureusandEscherichia coli, as well as its antioxidant activity and toxicity. Planktonic growth assays were performed, and the inhibition of biofilm formation was evaluated. In addition, antioxidant activity was assessed by DPPH radical scavenging assay, ferrous ion chelating assay, ferric-reducing antioxidant power assay, andβ-carotene bleaching assay. Toxicity was evaluated by the brine shrimp lethality test. Results showed that derriobtusone A completely inhibited the planktonic growth ofS. aureusat 250 and 500 μg/mL; however, it did not have the same activity onE. coli. Derriobtusone A reduced the biomass and colony-forming unit (cfu) ofS. aureusbiofilm at concentrations of 250 and 500 μg/mL. In various concentrations, it reduced the biofilm biomass ofE. coli, and, in all concentrations, it weakly reduced the cfu. Derriobtusone A showed highly efficient antioxidant ability in scavenging DPPH radical and inhibitingβ-carotene oxidation. The compound showed no lethality toArtemiasp. nauplii. In conclusion, derriobtusone A may be an effective molecule againstS. aureusand its biofilm, as well as a potential antioxidant compound with no toxicity.


2018 ◽  
Vol 7 (2) ◽  
Author(s):  
Hamadia Khurshid ◽  
Syed Mubashar Sabir ◽  
Shahid Iqbal Awan ◽  
Syed Rizwan Abbas ◽  
Muhammad Irshad

Rose petals have been applied as food additives in teas, cakes and flavor extracts. The aim of this research study was to explore and reveal the antioxidant potential of aqueous extracts of rose petals belonging to nine genotypes of rose (wild as well as hybrid). The in vitro antioxidant activities of roses were studied by lipid peroxidation assay, DPPH radical scavenging assay, iron chelation assay, phosphomolybdenum reduction assay and total phenolic and flavonoid contents. The aqueous extract showed inhibition against lipid peroxidation (TBARS), induced by prooxidants (10 µM FeSO4) in mice liver homogenate. The free radical scavenging activities of the extracts were determined by scavenging of the DPPH radical. Extracts also showed metal chelating activities and high antioxidant activity in the phosphomolybdenum assay. The high content of phenolics and flavonoids detected in aqueous extracts may be responsible for the antioxidant activity. Amongst the different rose genotypes, screened, Rosa moschata (musk rose) was found to carry slightly higher antioxidant potential, owing to its higher phytochemical content.


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