scholarly journals Studies on the microbial diversity of salted fishes under aerobic conditions

2010 ◽  
Vol 1 (1) ◽  
pp. 5 ◽  
Author(s):  
Lawrance Anbu Rajan ◽  
Toms C. Joseph ◽  
Nirmala Thampuran ◽  
Roswin James

A total of 93 isolates of halophilic and moderately halophilic bacteria were isolated from salted fishes, Scoliodon sp. and Thrissina thryssa obtained from retail fish outlets in Cochin, Kerala, India. The viable count of the bacteria in Scoliodon sp. and Thrissina thryssa ranged from 103-106 per g. The morphological, biochemical, and physiological investigations were done to characterize the isolates, which showed good growth in medium containing 3-10% (w/v) NaCl at 37°C. In Scoliodon sp. the maximum of 87.5% isolates were Gram-positive cocci and in Thrissina thryssa 95.5% of the isolates were Gram-positive rods. The optimum conditions such as temperature, pH, and salts (NaCl) were determined. The utilization of organic compounds such as fructose, lactose, glucose, sucrose, arabinose, trehalose, maltose, salicin, mannose, cellobiose, rhamnose, dulcitol, xylose, raffinose, sorbitol, adonitol, inulin, galactose, inositol, mannitol, hydrogen sulfide, nitrate, citrate utilization, MR-VP, triple sugar iron, as well as the hydrolysis of organic compounds such as casein, gelatin, aesculin, starch, Tween 20, and Tween 80 were also investigated. Moreover, an alkalophilic bacterial strain Bacillus halodurans (B. halodurans) was isolated from Thrissina thryssa and confirmed by 16S rDNA analysis. These studies revealed that salted fishes offer an optimal environment for the viable, diverse, potentially and industrially important bacterial community.

1963 ◽  
Vol 43 (1) ◽  
pp. 110-118 ◽  
Author(s):  
R. Ekholm ◽  
T. Zelander ◽  
P.-S. Agrell

ABSTRACT Guinea pigs, kept on a iodine-sufficient diet, were injected with Na131I and the thyroids excised from 45 seconds to 5 days later. The thyroid tissue was homogenized and separated into a combined nuclear-mitochondrial-microsomal fraction and a supernatant fraction by centrifugation at 140 000 g for one hour. Protein bound 131iodine (PB131I) and free 131iodide were determined in the fractions and the PB131I was analysed for monoiodotyrosine (MIT), diiodotyrosine (DIT) and thyroxine after hydrolysis of PB131I. As early as only 20 minutes after the Na131I-injection almost 100% of the particulate fraction 131I was protein bound. In the supernatant fraction the protein binding was somewhat less rapid and PB131I values above 90% of total supernatant 131I were not found until 3 hours after the injection. In all experiments the total amount of PB131I was higher in the supernatant than in the corresponding particulate fraction. The ratio between supernatant PB131I and pellet PB131I was lower in experiments up to 3 minutes and from 2 to 5 days than in experiments of 6 minutes to 20 hours. Hydrolysis of PB131I yielded, even in the shortest experiments, both MIT and DIT. The DIT/MIT ratio was lower in the experiments up to 2 hours than in those of 3 hours and over.


1970 ◽  
Vol 16 (12) ◽  
pp. 1165-1166 ◽  
Author(s):  
C. González ◽  
C. Gutierrez

The presence of lipase in 56 extremely halophilic bacteria was studied by using a plate method with Tweens 20, 40, and 80 as substrates for the enzyme. Thirty-five strains were positive and 21 were negative. Halobacterium salinarium did not hydrolyze any of the Tweens tested. H. cutirubrum hydrolyzed Tween 20 and 40. Micrococcus morrhuae hydrolyzed all Tweens tested. The application of lipase in halobacteria as a taxonomical character was emphasized, and its role in the spoilage of fatty products was considered.


2012 ◽  
Vol 554-556 ◽  
pp. 1400-1405
Author(s):  
Yan Duan ◽  
Wen Rui Guo ◽  
Lin Su ◽  
Yue Ying Guo ◽  
Ye Jin

A total of 69 gram-positive, catalase-negative strains isolated from Inner Mongolia traditional meat sausages were characterized in respect to their technological properties, including acid production, salt and nitrite tolerance, gas, slime and H2S production, hydrolysis of arginine and biogenic amine production. All of the isolated strains decrease the pH below 5.0 after 24h of cultivation. All isolates are able to grow with 6.5% NaCl or with 150mg L-1NaNO2and 51 isolates are able to grow with 10% NaCl. All isolates don’t produce gas and slime. 54 isolates don’t produce H2S. 23 isolated strains don’t produce NH3 from arginine, and 40 isolates don’t produce biogenic amine. Consolidation of these results, 8 strains show the best technological properties to be used as starter culture for sausage production. The bacterial selected are then subjected to biochemical tests using the API 50 CH and they are identified as 6 Lactobacillus planarum and 2 Lactobacillus curvatus.


2018 ◽  
Vol 10 (2) ◽  
pp. 20 ◽  
Author(s):  
Noor Mohammed Dawood ◽  
Shaimaa Nazar Abdal-hammid ◽  
Ahmed Abbas Hussien

Objective: The objective of this study was to prepare nanosuspension of a practical water insoluble antiulcer drug which is lafutidine to enhance the solubility, dissolution rate with studying the effect of different formulation variables to obtain the best formula with appropriate physical properties and higher dissolution rate.Methods: Nanosuspension of lafutidine was prepared using solvent anti-solvent precipitation method using Polyvinylpyrrolidone K-90(PVP K-90) as the stabilizer. Ten formulations were prepared to show the effect of different variables in which two formulations showed the effect of stabilizer type, three formulations showed the effect of stabilizer concentration, two formulations showed the effect of combination of polymer with surfactant such as tween 80, three formulations show the effect of stirring speed and three formulations prepare to show the effect of addition of co-surfactant such as tween 20. All these formulations are evaluated for their particle size and entrapment efficiency and in vitro release. The selected one was evaluated for zeta potential, scanning electron microscope, atomic force microscopy, Fourier transforms infrared spectroscopy, differential scanning calorimetry, saturation solubility and stability study.Results: The formulations (F3-F10) were in the nano size. The optimum concentration of the stabilizer was in the formulation when the drug: polymer: surfactant ratio 1:4:4 and the optimum stirring speed was 1500 rpm. Dramatic effect on the particle size reduction was found by the addition of co-surfactant (tween 20) in formulation F7 that has a particle size 15.89±1.8 nm. The selected formula F7 showed an enhanced dissolution profile (10 min) compared to the pure drug at all-time intervals.Conclusion: The results show that the formulation that contains drug: PVP-K90: tween 80: tween 20 in ratio 1:4:2:2 is the best one and can be utilized to formulate lafutidine nanosuspension. 


Author(s):  
SARAH LABIB ◽  
MOHAMED NASR ◽  
MOHAMED NASR

Objective: The main objective of this study was to develop atorvastatin calcium (ATR) as an oral drug delivery system for a P-glycoprotein (P-gp) substrate drug using different pharmaceutical excipients that inhibit P-glycoprotein and evaluate the influence of nanocrystals on the dissolution characteristics and bioavailability compared to the plain drug. Methods: A nanosuspension was prepared by Solvent-antisolvent precipitation method using a solvent containing stabilizer that act as a p-gp inhibitor dissolved in distilled water as polyethylene glycol 300, polyethylene glycol 400 (PEG 300, PEG 400), tween 20 and tween 80 while the solvent selected for atorvastatin calcium was methanol. The concentrations were as follows: PEG 300 and 400 = 0.25% w/v, tween 20 and 80 = 0.75% v/v. Nanocrystals were extracted from the suspension and characterized. Results: Particle size of the drug was 1307±127.79 nm while the formulas prepared ranged from 223±17.67 to 887±58.12 nm. Pure ATR had a saturated solubility of 0.059±0.005 mg/ml and the prepared nanocrystals ranged from 0.32±0.021 to 0.88±0.019 mg/ml. The Percentage of drug released of plain atorvastatin calcium reached 41.49% while the formula ranged from 44.32 to 61.5%. Both XRD and SEM discussed the degree of crystallinity as follows: F1<F2<F4<F3<ATR. Conclusion: 0.3% of PEG 300 and PEG 400 were not enough to formulate proper nanocrystals while 0.75% tween 20 and tween 80 achieved acceptable formulas. F4 which is prepared with tween 80 exhibited the highest enhancement in saturated solubility, dissolution rate and subsequently expected to have improved oral bioavailability.


Author(s):  
ABEER A. EL-HADI ◽  
HANAN MOSTAFA AHMED ◽  
RANIA A. ZAKI ◽  
AMIRA MOHAMED MOHSEN

Objective: L-asparaginase (L-asp) is a vital enzyme used as a therapeutic agent in combination with other drugs in the treatment of acute lymphoma, melanosarcoma and lymphocytic leukemia. Immobilization of enzymes through loading on nanoemulsion (NE) results in some advantages such as enhancing their stability and increasing their resistance to proteases. Aim of the present study is to formulate L-asp loaded nanoemulsion to enhance its efficiency and thermal stability. Methods: Nanoemulsion loaded with L-asp crude extract (specific activity 13.23U/mg protein) was prepared employing oleic acid as oil, tween 20/tween 80 as surfactants and propylene glycol (PG) as co-surfactant. L-asp loaded NE underwent several thermodynamic stability studies and the optimized formulae were further examined for their biochemical properties and thermal stability. Results The developed formulations were spherical in shape and their sizes were in the nanometric dimensions with negatively charged zeta potential values. Upon comparing the enzyme activity of L-asp loaded NE employing tween 20 (F1) or tween80 (F4) at different concentrations, the results revealed that F4 NE showed higher enzymatic activity [323 U/ml] compared to F1 NE [197 U/ml] at the same concentration. The nanosized immobilized L-asp was more stable in the pH range from 8 to 8.5 as compared to free L-asp. The immobilized enzyme preserved about 59.11% of its residual activity at 50 °C; while free L-asp preserved about 33.84%. Conclusion: In the view of these results, NE composed of oleic acid, tween 80 and PG represents a promising dosage form for enhancing the activity and stability of Streptomyces griseoplanus L-asp.


2018 ◽  
Vol 112 ◽  
pp. 734-740 ◽  
Author(s):  
Cleitiane da Costa Nogueira ◽  
Carlos Eduardo de Araújo Padilha ◽  
Ana Laura de Sá Leitão ◽  
Patrícia Maria Rocha ◽  
Gorete Ribeiro de Macedo ◽  
...  

Author(s):  
Nurhabibah Nurhabibah ◽  
A.K. Nugroho ◽  
Ronny Martien ◽  
Endang Lukitaningsih

This study aimed to determine the solubility of lovastatin (LV) in different oil, surfactant, and co-surfactant using the high-performance liquid chromatography method. LV was solubility studies in different vehicle. The different vehicle used almond oil, sunflower oil, oleic acid, olive oil, soybean oil, and corn oil, isoprophyl myristate, myoglyol, tween 80, tween 20, and cremophor R.H. 40, propylene glycol, and PEG 400. Each of them was added lovastatin until saturated. The mixtures were mixing, sonicating, putting in the water bath and standing for 24 hours, then centrifugated. Each of the aliquot 2 µL diluted with acetonitrile and determination of concentration lovastatin using HPLC, with detector ultraviolet at 237 nm. Before determinate LV validated, and curve calibration at range 2-16 µg/mL was made. This study using the HPLC method with detector UV 237 nm, Agilent C 18 (4.6 x 150 mm 5 µ) column, and acetonitrile: water (70:30 v/v) as mobile phase. Calibration curve of lovastatin at the range 2-16 µg/mL with linear regression 0.999. Accuracy and precision showed that. Lovastatin has high soluble in oleic acid, tween 80, and PEG 400.


2018 ◽  
Vol 8 (19) ◽  
Author(s):  
Carolyn L. Nanca ◽  
Kimberly D. Neri ◽  
Anna Christina R. Ngo ◽  
Reuel M. Bennett ◽  
Gina R. Dedeles

Background. Polycyclic aromatic hydrocarbons (PAHs) are common environmental contaminants which are highly toxic due to their carcinogenic and mutagenic effects. They are released into the environment by incomplete combustion of solid and liquid fuels, accidental spillage of oils and seepage from industrial activities. One of the promising processes mitigating PAHs is through biodegradation. However, conventional microbiological treatment processes do not function well at high salt concentrations. Hence, utilization of halophilic bacteria should be considered. Objectives. This study aimed to assess the ability of halophilic bacteria isolated from local salt beds in Pangasinan and Cavite, the Philippines, to degrade PAHs pyrene, fluorene and fluoranthene. Methods. Polycyclic aromatic hydrocarbon-tolerant halophilic bacteria collected from two sampling sites were phenotypically characterized, molecularly identified and tested to determine their potential to degrade the PAHs pyrene, fluorene and fluoranthene at a hypersaline condition. Best PAH degraders were then assayed to identify the optimal degradation using such parameters as pH, temperature and PAH concentration. Testing for enzyme degradation was also done to determine their baseline information. Extraction and analysis of degraded PAHs were performed using centrifugation and UV-vis spectrophotometry. Results. Twelve isolates from both collection sites tolerated and grew in culture with selected PAHs. These were identified into four genera (Halobacillus, Halomonas, Chromohalobacter, and Pontibacillus). Selected best isolates in a series of biodegradation assays with the above-mentioned parameters were Halobacillus B (Collection of Microbial Strains (CMS) 1802) (=trueperi) (Gram-positive) for pyrene and fluoranthene, and Halomonas A (CMS 1901) (Gram-negative) for fluorene. Degrader biomass and PAH degradation were invariably negatively correlated. Qualitative tests with and without peptone as a nitrogen source implied enzymatic degradation. Discussion. Polycyclic aromatic hydrocarbons utilized by these halophilic bacteria served as a sole source of carbon and energy. Implications of biodegradation of the two best isolates show that high molecular weight (HMW) (4-ring) pyrene tends to be degraded better by Gram-positive bacteria and low molecular weight (3-ring) fluorene by Gram-negative degraders. Conclusions. Halophilic bacteria constitute an untapped natural resource for biotechnology in the Philippines. The present study demonstrated their potential use in bioremediation of recalcitrant hydrocarbons in the environment. Competing Interests. The authors declare no competing financial interests.


Sign in / Sign up

Export Citation Format

Share Document