scholarly journals Isolation of agarase-producing bacteria from seawater and examination of the enzyme activity

2020 ◽  
Vol 19 (02) ◽  
pp. 50-58
Author(s):  
Thanh T. L. Bien
Keyword(s):  
Incubation Period ◽  
Room Temperature ◽  
Reducing Sugar ◽  
Crude Enzyme ◽  
Surface Seawater ◽  
Bacterial Strains ◽  
Agarase Activity ◽  
Seawater Samples ◽  
Hydrolysis Of ◽  
Vibrio Genus

This study aimed to isolate agarase-producing bacteria from seawater, and then determine activity of the agarase. Eight coastal surface seawater samples were collected from Ba Ria - Vung Tau province. Twenty-one bacterial strains that are capable of liquefying agar were isolated. These isolates produced disintegration zones around their colonies on agar plates with diameters ranging from 4.0 to 7.0 cm after an incubation period of 2 days at room temperature. Five bacterial strains (M1, M5, M7, M62B, and M71) that produced large halos on plates were identified belonging to Vibrio genus with identity > 96%. The crude enzyme activities of these strains ranged from 0.15 to 0.22 U/mL in reaction with agarose as substrate. Among isolated strains, the strain M71 showed the highest agarase activity, and was used to examine the degradation of seaweed. The hydrolysis of dried Gracilaria seaweed by the crude enzyme of M71 at concentration of 5% (v/v) released 915 μM/mL reducing sugar after a 24-h incubation period at 40oC.

Lattice imaging and pore structure of β ferric oxyhydroxide

1978 ◽  
Vol 36 (1) ◽  
pp. 264-265
Author(s):  
T. Baird ◽  
J.R. Fryer ◽  
S.T. Galbraith
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bulk Material ◽  
Model Structure ◽  
Bulk Crystals ◽  
Lattice Imaging ◽  
Thin Sections ◽  
Ferric Oxyhydroxide ◽  
Resolution Electron ◽  
Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

Effect of Temperature on ADP-Induced Platelet Aggregation

1973 ◽  
Vol 29 (01) ◽  
pp. 183-189
Author(s):  
C. A Praga ◽  
E. M Pogliani
Keyword(s):  
Platelet Aggregation ◽  
Incubation Period ◽  
Room Temperature ◽  
Important Variable ◽  
Practical Significance ◽  
Effect Of Temperature ◽  
Induce Platelet Aggregation ◽  
Cuvette Holder ◽  
Exact Temperature

SummaryTemperature represents a very important variable in ADP-induced platelet aggregation.When low doses of ADP ( < 1 (μM) are used to induce platelet aggregation, the length of the incubation period of PRP in the cuvette holder of the aggregometer, thermostatted at 37° C, is very critical. Samples of the same PRP previously kept at room temperature, were incubated for increasing periods of time in the cuvette of the aggregometer before adding ADP, and a significant decrease of aggregation, proportional to the length of incubation, was observed. Stirring of the PRP during the incubation period made these changes more evident.To measure the exact temperature of the PRP during incubation in the aggre- gometer, a thermocouple device was used. While the temperature of the cuvette holder was stable at 37° C, the PRP temperature itself increased exponentially, taking about ten minutes from the beginning of the incubation to reach the value of 37° C. The above results have a practical significance in the reproducibility of the platelet aggregation test in vitro and acquire particular value when the effect of inhibitors of ADP induced platelet aggregation is studied.Experiments carried out with three anti-aggregating agents (acetyl salicyclic acid, dipyridamole and metergoline) have shown that the incubation conditions which influence both the effect of the drugs on platelets and the ADP breakdown in plasma must be strictly controlled.

Total Synthesis and Antibacterial Screening of (±)-6,8-Dihydroxy-3- undecyl-3,4-dihydroisochromen-1-one: A Structural Analogue of Metabolites from Ononis natrix

2019 ◽  
Vol 16 (3) ◽  
pp. 245-248
Author(s):  
Hummera Rafique ◽  
Aamer Saeed ◽  
Ehsan Ullah Mughal ◽  
Muhammad Naveed Zafar ◽  
Amara Mumtaz ◽  
...  
Keyword(s):  
Total Synthesis ◽  
Structural Analog ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Antibacterial Screening ◽  
Maximum Inhibition ◽  
Bacillus Subtilus ◽  
Hydrolysis Of ◽  
Direct Condensation

Background: (±)-6,8-Dihydroxy-3-undecyl-3,4-dihydroisochromen-1-one is one of the structural analog of several substituted undecylisocoumarins isolated from Ononis natrix (Fabaceae), has been successfully synthesized by direct condensation of homopthalic acid (1) with undecanoyl chloride yields isochromen-1-one (2). Methods: Alkaline hydrolysis of (2) gave the corresponding keto-acid (3), which is then reduced to hydroxy acid (4) then its cyclodehydration was carried out with acetic anhydride to afford 3,4- dihydroisochromen-1-one (5). Followed by demethylation step, the synthesis of target 6,8- dihydroxy-7-methyl-3-undecyl-3,4-dihydroisocoumarin (6) was achieved. Results: In vitro antibacterial screening of all the synthesized compounds were carried out against ten bacterial strains by agar well diffusion method. Conclusion: Newly synthesized molecules exhibited moderate antibacterial activity and maximum inhibition was observed against Bacillus subtilus and Salmonella paratyphi.

Process intensification for enzyme assisted turmeric starch hydrolysis in hydrotropic and supercritical conditions

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Yogita P. Labrath ◽  
Prafulla V. Belge ◽  
Uma G. Kulkarni ◽  
Vilas G. Gaikar
Keyword(s):  
Residence Time ◽  
Filtration Rate ◽  
Room Temperature ◽  
Curcuma Longa ◽  
Process Intensification ◽  
Enzyme Treatment ◽  
Starch Hydrolysis ◽  
Reaction Conditions ◽  
Natural Form ◽  
Hydrolysis Of

Abstract The turmeric rhizome (Curcuma longa) contains curcuminoids embedded in the starch matrix. It is thus important to target starch hydrolysis to enhance extraction of curcuminoids. In the case of starch hydrolysis, α-amylase is more efficient when the starch is in a gelatinised form than when it is in its natural form. The present work includes hydrolysis of turmeric starch in its natural and gelatinised forms using α-amylase in hydrotrope solution (HS) and scCO2. The optimum rate of starch hydrolysis was obtained using 200 IU cm−3 of α-amylase, at reaction conditions of 6.5 pH at 328 K when 10% w/w of turmeric powder was stirred at 900 rpm in HSs. The hydrolysis in 15 MPa scCO2 at room temperature required a phase modifier and 40 min of residence time (RT). The enzyme treatment of turmeric powder in HSs increased the filtration rate for curcuminoid extraction (gelatinised and native) compared to untreated turmeric powder.

scholarly journals Novel Amino Acid Derivatives of Quinolines as Potential Antibacterial and Fluorophore Agents

2020 ◽  
Vol 88 (4) ◽  
pp. 57
Author(s):  
Oussama Moussaoui ◽  
Rajendra Bhadane ◽  
Riham Sghyar ◽  
El Mestafa El Hadrami ◽  
Soukaina El Amrani ◽  
...  
Keyword(s):  
Amino Acid ◽  
Methyl Esters ◽  
Amino Acid Derivatives ◽  
Bacterial Strains ◽  
Fluorescent Properties ◽  
Topoisomerase Iv ◽  
Microdilution Method ◽  
Hydrolysis Of ◽  
Derivatives Of

A new series of amino acid derivatives of quinolines was synthesized through the hydrolysis of amino acid methyl esters of quinoline carboxamides with alkali hydroxide. The compounds were purified on silica gel by column chromatography and further characterized by TLC, NMR and ESI-TOF mass spectrometry. All compounds were screened for in vitro antimicrobial activity against different bacterial strains using the microdilution method. Most of the synthesized amino acid-quinolines show more potent or equipotent inhibitory action against the tested bacteria than their correspond esters. In addition, many of them exhibit fluorescent properties and could possibly be utilized as fluorophores. Molecular docking and simulation studies of the compounds at putative bacterial target enzymes suggest that the antimicrobial potency of these synthesized analogues could be due to enzyme inhibition via their favorable binding at the fluoroquinolone binding site at the GyrA subunit of DNA gyrase and/or the ParC subunit of topoisomerase-IV.

The Formation of Plasma Acid at Atmospheric Pressure and its Application in Hydrolysis of Microcrystalline Cellulose

2013 ◽  
Vol 750-752 ◽  
pp. 1626-1629
Author(s):  
Bo Yuan ◽  
Ying Wang ◽  
Ying Chao Ji ◽  
Qiu Hong Wang
Keyword(s):  
Microcrystalline Cellulose ◽  
Atmospheric Pressure ◽  
High Performance ◽  
Barrier Discharge ◽  
Ph Value ◽  
Reducing Sugar ◽  
Dielectric Barrier ◽  
Integrated Optical ◽  
Hydrolysis Of ◽  
Single Factor Experiment

In this paper, plasma acid was obtained by treating distilled water with dielectric barrier discharge at atmospheric pressure in order to hydrolyze cellulose. The acidity of plasma acid was studied through a single factor experiment. A plasma acid with pH value of 1.42 was obtained and used to hydrolyze microcrystalline cellulose at 80°C for 60min. Under this condition, the integrated optical density (IOD) of the hydrolysis sample was 0.589. Based on standard glucose curve, the total reducing sugar (TRS) was calculated to be 53.75mg and the TRS yield was 53.75%. The filtrate was evaporated to get the solid hydrolysis sample to be analyzed by High-performance liquid chromatography (HPLC). The results showed that the sample mainly consisted of glucose, which proved that microcrystalline cellulose could be hydrolyzed by plasma acid. Therefore, it could be concluded that it was an environmentally friendly and economical method to hydrolyze the microcrystalline cellulose by plasma acid.

The synthesis of Cyclododecane-r-1,c-5,c-9-triamine and r-1,c-5,c-9-Tris(2,3-dimethoxybenzamido)cyclododecane

1975 ◽  
Vol 28 (3) ◽  
pp. 673 ◽  
Author(s):  
DJ Collins ◽  
C Lewis ◽  
JM Swan
Keyword(s):  
Aqueous Solution ◽  
Acid Hydrolysis ◽  
Sulphuric Acid ◽  
Sodium Carbonate ◽  
Sodium Azide ◽  
Room Temperature ◽  
Dimethyl Formamide ◽  
Lithium Aluminium Hydride ◽  
Lithium Aluminium ◽  
Hydrolysis Of

Treatment of cyclododecane-r-1,c-5,c-9-triyl tris(p-toluenesulphonate) with sodium azide in dimethyl-formamide at 100� for 6 h gave the corresponding cis,cis-triazide which upon hydrogenation or reduction with lithium aluminium hydride gave cyclododecane-r-1,c-5,c-9-triamine, isolated as the tris-salicylidene derivative. Acid hydrolysis of this, removal of the salicylaldehyde, and treatment of the aqueous solution with sodium carbonate and 2,3-dimethoxybenzoyl chloride gave r-1,c-5,c- 9-tris(2,3-dimethoxybenzamido)cyclododecane. ��� Treatment of (E,E,E)-cyclododeca-1,5,9-triene with an excess of acetonitrile and sulphuric acid at room temperature for three days gave 18% of (E,E)-1-acetamidocyclododeca-4,8-diene; no di- or tri-amides were isolated.

Room Temperature Hydrolysis of Benzamidines and Benzamidiniums in Weakly Basic Water

2021 ◽  
Vol 86 (19) ◽  
pp. 13762-13767 ◽  
Author(s):  
Li-Juan Yu ◽  
Duncan A. Cullen ◽  
Mahbod Morshedi ◽  
Michelle L. Coote ◽  
Nicholas G. White
Keyword(s):  
Room Temperature ◽  
Hydrolysis Of

scholarly journals Extensive destruction of newly synthesized casein in mammary explants in organ culture

1982 ◽  
Vol 202 (1) ◽  
pp. 133-138 ◽  
Author(s):  
Huthama Razooki Hasan ◽  
David A. White ◽  
R. John Mayer
Keyword(s):  
Incubation Period ◽  
Soluble Protein ◽  
Milk Protein ◽  
Fatty Acid Synthetase ◽  
Total Soluble Protein ◽  
Signal Peptides ◽  
Dual Isotope ◽  
Intracellular Degradation ◽  
Hydrolysis Of ◽  
Specific Particle

1. Explants of mammary glands of mid-pregnant rabbits that had been cultured for 18h in the presence of insulin, prolactin and cortisol were incubated at 37°C for 2h in Medium 199 containing l-[4,5-3H]leucine. After a wash procedure at 4°C, explants were re-incubated at 37°C in fresh medium and the radioactivity of casein polypeptides isolated by isoelectric focusing (at pH 4.6) was followed with time. Casein radioactivity rose during the first hour of re-incubation, but fell markedly during the subsequent hour. 2. Loss of radioactivity represented casein degradation, since less than 10% of newly synthesized casein was found in the incubation medium. 3. Such a loss of radioactivity was not due solely to hydrolysis of signal peptides, since similar results were obtained when l-[5-3H]proline, which is not part of casein signal peptides, was the radiolabelled precursor. 4. A dual-isotope experiment using l-[U-14C]proline and N-[3H]acetyl-d-mannosamine gave similar profiles of radioactivity loss from isoelectrically focused casein, indicating that degradation of mature casein was occurring. 5. Analysis of total pellet and particle-free-supernatant fractions prepared by centrifugation of explant homogenates at 115000gav. for 1h did not show loss of radioactivity on re-incubation. Total pellet-protein radioactivity remained constant, whereas total soluble-protein radioactivity increased during the 2h re-incubation period. 6. Radioactivity in a specific particle-free-supernatant polypeptide, the subunit of fatty acid synthetase, mimicked that of the total soluble protein. 7. Addition of cycloheximide (20μg/ml) during the re-incubation period completely blocked the incorporation of radioactivity from l-[5-3H]proline into casein and the subsequent fall, indicating that observations were being made on newly synthesized casein. 8. Addition of chloroquine (50μm) did not prevent the increase in radioactivity from l-[5-3H]proline into casein during the first hour of re-incubation, but did prevent the loss of radioactivity in the second hour. 9. The intracellular degradation of a newly synthesized milk protein is discussed in relation to the known intracellular degradation of other secretory polypeptides.

scholarly journals Development and Evaluation of Whey-based Herbal Beverages as Health Drink

2021 ◽  
Vol 108 (March) ◽  
pp. 1-5
Author(s):  
Kanchana N ◽  
◽  
Veeranan Arun Giridhari V ◽  
Vijayalakshmi R ◽  
◽  
...  
Keyword(s):  
Room Temperature ◽  
Sensory Attributes ◽  
Reducing Sugar ◽  
Soluble Solids ◽  
Protein G ◽  
Total Soluble Solids ◽  
Sensory Acceptability ◽  
Titrable Acidity ◽  
Physical Chemical ◽  
The Cost

The present study aimed to developwhey-based herbal beverages and to evalautetheir physical, chemical, and sensory properties. The pH, titrable acidity (% lactic acid) and total soluble solids (⁰Brix) of whey used for the development of whey based herbal drinks were found to be 5.21, 0.23 and 6.4 respectively. The proximate composition of whey such as lactose (g/100g), protein (g/100g) and fat (g/100g) were 4.28, 0.28 and 0.13, respectively. The whey (65%), sugar (11%), H1 - brahmi extract (3%), H2 - mint extract (2%) and H3 - jaljeera powder (0.15%) were standardized for the formulation of whey-based herbal drinks. Among the three variations, whey-based jaljeera drink (H3) scored the highest sensory acceptability. The pH, titrable acidity (% citric acid), total soluble solids (⁰Brix), lactose (g/100g), protein (g/100g), fat (g/100g), total reducing sugar (g/100g), total sugar (g/100g), calcium (mg/100g), ascorbic acid (mg/100g) and total phenol (mgGAE/100g) of whey-jaljeera drink (H3) were 5.24, 0.21, 12.0, 2.78, 0.46, 0.30, 3.43, 14.43, 55.27, 0.12 and 14.26, respectively. The sensory attributes retention was high in glass (P2) compared to PET (P1). The sensory attributes were gradually decreased during the storage of room temperature (R1) than refrigerated temperature (R2). The cost of the formulated whey brahmi drink, whey mint drink, and whey jaljeera drinks were Rs.18.33/250ml, Rs.20.20/250ml and Rs.14.75/250ml, respectively. The study concluded that nutritionally rich whey-based herbal drinks can be recommended to all group of people.

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