scholarly journals A Method for the Isolation and Characterization of Mycosporine-Like Amino Acids from Cyanobacteria

2018 ◽  
Vol 1 (4) ◽  
pp. 46 ◽  
Author(s):  
Siripat Ngoennet ◽  
Yasuhiro Nishikawa ◽  
Takashi Hibino ◽  
Rungaroon Waditee-Sirisattha ◽  
Hakuto Kageyama

This report provides a broadly applicable and cost-effective method for the purification of mycosporine-like amino acids (MAAs) from cyanobacteria. As MAAs are known to have multiple bioactivities for health and beauty, a universal isolation method of MAAs from biomass is attractive. In particular, the biomass of photosynthetic microorganisms such as cyanobacteria is of interest as a natural source of useful compound production, because of their photoautotrophic property. The method presented here is applicable for the isolation of mycosporine-2-glycine (M2G), which is a rare MAA produced in a halotolerant cyanobacterium. This method also allowed for the isolation of two of the most common MAAs, shinorine (SHI) and porphyra-334 (P334). A three-step separation process using low pressure liquid chromatography yielded purified MAAs, which were characterized by nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry (LC/MS) analyses. The purified MAAs exhibited free radical scavenging activity in the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay. The experimental parameters obtained in this report may allow for a scale-up of the MAA purification process for future industrial applications.

2021 ◽  
Vol 38 (1) ◽  
pp. 1-5
Author(s):  
Md Arifur Rahman ◽  
Ahmed Abu Rus’d ◽  
Md Enamul Haque

Sonneratia apetala (S. apetala) (Lythraceae) has been investigated for the isolation and characterization of antimicrobial compounds and evaluation of their biological activities. The chloroform extract of the stem bark and different partitionate of the chloroform extracts i.e. Petroleum ether soluble fraction (PESF), Ethyl acetate soluble fraction(EASF), Methanol soluble fraction(MSF) and aqueous soluble fractions (ASF) were subjected to different chromatographic techniques to isolate secondary metabolites. Successive chromatographic separation and purification yielded a total of two compounds identified and characterized as Taraxerone(1) and 5,8-dihydroxy- 6-methoxy-4,9-dioxo-1,3,4,9-tetrahydronaphthol[2,3-c]furan-1-yl acetate (2) by extensive proton NMR spectrum (1H-NMRspectrum) analysis. The different partitionate like PESF, EASF, MESF and ASF were subjected to screen their antimicrobial properties against some selected Gram positive and Gram negative bacteria and fungi, brine shrimp lethality and antioxidant activities. The maximum zone of inhibition of chloroform extract was found against Pseudomonas sp. (16mm). All fractions showed more activity against Gram negative bacteria then Gram positive bacteria. In the brine shrimp lethality bioassay, among all extracts, the petroleum ether and ethyl acetate soluble fraction showed significant lethality having the LC50 value of 7.72 μg/ml. The antioxidant activity was evaluated in terms of determination of free radical scavenging activity (DPPH assay). Among all the extracts of S. apetala the highest free radical scavenging activity showed by (Methanol soluble fraction) MESF with IC50 value 18.0 μg/ml. Bangladesh J Microbiol, Volume 38, Number 1, June 2021, pp 1-5


Foods ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 822 ◽  
Author(s):  
Maria Simona Chiş ◽  
Adriana Păucean ◽  
Simona Maria Man ◽  
Victorița Bonta ◽  
Anamaria Pop ◽  
...  

Lactobacillus Spicheri DSM 15429 strain was used to ferment rice flour, aiming at exploiting its influence on the amino-acids, minerals, lactic acid, total phenols, and antioxidant activity of the rice sourdough and gluten-free muffins. Gluten-free muffins were prepared by using 15% rice sourdough fermented with the above strain of lactic acid bacteria and compared with rice spontaneous fermentation. Methods like LC-MS (Liquid chromatography–mass spectrometry), AA (atomic absorption), HPLC (High-performance liquid chromatography), Folin–Ciocalteu, and 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity (DPPH) were used to fulfill the aim of the study. The addition of rice sourdough fermented with LAB was reflected in the chemical composition of the final baked good, improving its amount on bioactive compounds such as amino acids, mineral bioavailability, total phenols, and antioxidant activity. Total phenols and antioxidant activity increased their amount by 70.53% and 73.70%, respectively, meanwhile, lactic acid, minerals, and amino-acids increased their values at least twice. Thus, rice fermented with Lactobacilus spicheri DSM 15429 strain could be a tool to further increase the nutritional value of gluten-free baked products.


Marine Drugs ◽  
2021 ◽  
Vol 20 (1) ◽  
pp. 40
Author(s):  
Paula Santiago-Díaz ◽  
Argimiro Rivero ◽  
Milagros Rico ◽  
Juan Luis Gómez-Pinchetti

The biochemical composition of three novel selected microalgae strains (Chlorophyta) was evaluated to confirm their potential possibilities as new sustainably produced biomass with nutritional, functional, and/or biomedical properties. Extracts from cultured Pseudopediastrum boryanum, Chloromonas cf. reticulata, and Chloroidium saccharophilum exhibited higher radical scavenging activity of DPPH (1,1-diphenyl-2-picrylhydrazyl) when compared to butylated hydroxytoluene (BHT), but lower than butylated hydroxyanisole (BHA). Total phenolic compounds and amino acids were determined by newly developed RP-HPLC methods. Total phenolic contents, as µg g−1 of dry biomass, reached 27.1 for C. cf. reticulata, 26.4 for P. boryanum, and 55.8 for C. saccharophilum. Percentages of total analysed amino acids were 24.3, 32.1, and 18.5% of dry biomass, respectively, presenting high values for essential amino acids reaching 54.1, 72.6, and 61.2%, respectively. Glutamic acid was the most abundant free amino acid in all microalgae samples, followed by proline and lysine in C. saccharophilum and P. boryanum, and methionine and lysine in C. reticulata. Soluble carbohydrates in aqueous extracts ranged from 39.6 for C. saccharophilum to 49.3% for C. reticulata, increasing values to 45.1 for C. saccharophilum and 52.7% for P. boryanum in acid hydrolysates of dried biomass. Results confirmed the potential possibilities of these microalgae strains.


Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2033
Author(s):  
Chuleeporn Bungthong ◽  
Sirithon Siriamornpun

Silk proteins have many advantageous components including proteins and pigments. The proteins—sericin and fibroin—have been widely studied for medical applications due to their good physiochemical properties and biological activities. Various strains of cocoon display different compositions such as amino-acid profiles and levels of antioxidant activity. Therefore, the objectives of this study were to find a suitable silk protein extraction method to obtain products with chemical and biological properties suitable as functional foods in two strains of Bombyx mori silk cocoon (Nangsew strains; yellow cocoon) and Samia ricini silk cocoon (Eri strains; white cocoon) extracted by water at 100 °C for 2, 4, 6 and 8 h. The results showed that Nangsew strains extracted for 6 h contained the highest amounts of protein, amino acids, total phenolics (TPC) and total flavonoids (TFC), plus DPPH radical-scavenging activity, ABTS radical scavenging capacity, and ferric reducing antioxidant power (FRAP), anti-glycation, α-amylase and α-glucosidase inhibition. The longer extraction time produced higher concentrations of amino acids, contributing to sweet and umami tastes in both silk strains. It seemed that the bitterness decreased as the extraction time increased, resulting in improvements in the sweetness and umami of silk-protein extracts.


Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3476 ◽  
Author(s):  
Jumana Abu-Khalaf ◽  
Razan Saraireh ◽  
Saleh Eisa ◽  
Ala’aldeen Al-Halhouli

This paper introduces a cost-effective method for the fabrication of stretchable circuits on polydimethylsiloxane (PDMS) using inkjet printing of silver nanoparticle ink. The fabrication method, presented here, allows for the development of fully stretchable and wearable sensors. Inkjet-printed sinusoidal and horseshoe patterns are experimentally characterized in terms of the effect of their geometry on stretchability, while maintaining adequate electrical conductivity. The optimal fabricated circuit, with a horseshoe pattern at an angle of 45°, is capable of undergoing an axial stretch up to a strain of 25% with a resistance under 800 Ω. The conductivity of the circuit is fully reversible once it is returned to its pre-stretching state. The circuit could also undergo up to 3000 stretching cycles without exhibiting a significant change in its conductivity. In addition, the successful development of a novel inkjet-printed fully stretchable and wearable version of the conventional pulse oximeter is demonstrated. Finally, the resulting sensor is evaluated in comparison to its commercially available counterpart.


2006 ◽  
Vol 116-117 ◽  
pp. 402-405 ◽  
Author(s):  
Qin Yue Pan ◽  
Stuart Wiesner ◽  
Diran Apelian

The continuous rheoconversion process (CRP) is a novel slurry-on-demand process that was developed at MPI/WPI in 2002. The process is based on a passive liquid mixing technique in which the nucleation and growth of the primary phase are controlled using a specially designed “reactor”. The reactor provides heat extraction, copious nucleation, and forced convection during the initial stage of solidification, thus leading to the formation of globular structures. This paper presents our recent work on the scale-up of the CRP for industrial applications. Specifically, we demonstrate an important application of the CRP to low temperature (low fraction solid) HPDC. In Part I of this paper, we present salient results on microstructural characterization of CRP processed castings vs. conventional die castings.


2012 ◽  
Vol 9 (1) ◽  
pp. 113-120 ◽  
Author(s):  
Yogesh Kumar Sharma ◽  
Dau Dayal Agarwal ◽  
Sudesh Bhure ◽  
Sanjay Singh Rathore ◽  
Chakravir Rawat ◽  
...  

Three known impurities in oseltamivir phosphate bulk drug at level 0.1% (ranging from 0.05-0.1%) were detected by gradient reverse phase high performance liquid chromatography. These impurities were preliminarily identified by the mass number of the impurities. Different experiments were conducted and finally the known impurities were synthesized and characterized.


Pathogens ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 82 ◽  
Author(s):  
Erminia La Camera ◽  
Carlo Bisignano ◽  
Giuseppe Crisafi ◽  
Antonella Smeriglio ◽  
Marcella Denaro ◽  
...  

We characterized a number of clinical strains of Staphylococcus spp. and investigated their sensitivity against polyphenols-rich extracts from natural raw and roasted pistachios (NPRE and RPRE, respectively). Out of 31 clinical isolates of Staphylococcus spp., 23 were coagulase-positive and identified as S. aureus, of which 21 were MRSA. Polyphenols-rich extracts from natural pistachios and roasted pistachios were prepared: the total phenols content, expressed as gallic acid equivalent (GAE)/100 g fresh weight (FW), was higher in natural pistachios (359.04 ± 8.124 mg) than roasted pistachios (225.18 ± 5.055 mg). The higher total phenols content in natural pistachios also correlated to the higher free-radical scavenging activity found by DPPH assay: NPRE and RPRE showed IC50 values of 0.85 (C.L. 0.725–0.976 mg mL−1) and 1.15 (C.L. 0.920–1.275 mg mL−1), respectively. Both NPRE and RPRE were active against S. aureus 6538P and Staph. spp. clinical isolates, with RPRE being the most active (MIC values ranging between 31.25 and 2000 μg mL−1). The antimicrobial potential of pistachios could be used to identify novel treatments for S. aureus skin infections.


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