scholarly journals A survey on the presence of listeria species in raw milk, ice cream and human stools with characterization of some isolates by sds-page

2004 ◽  
Vol 50 (101) ◽  
pp. 94-109
Keyword(s):  
Ice Cream ◽  
Raw Milk ◽  
Listeria Species ◽  
Sds Page

Prevalence of Listeria species in raw milk, ice cream and yogurt and effect of selected natural herbal extract on its survival

2020 ◽  
Vol 21 (3) ◽  
pp. 99-106
Author(s):  
Mona Yousef ◽  
Hazem Ramadan ◽  
Maha Al-Ashmawy
Keyword(s):  
Plant Extract ◽  
Reduction Rate ◽  
Ice Cream ◽  
Raw Milk ◽  
Inhibitory Effect ◽  
Food Preservation ◽  
Herbal Extract ◽  
Listeria Species ◽  
Soft Cheese ◽  
High Reduction

Objective: This study aimed to detect the prevalence of Listeria species in raw milk, ice cream and yogurt, and to evaluate the effect of extract of clove, thyme and pomegranate peel on such organism. Design: Descriptive study. Procedures: One hundred and fifty samples of milk, ice cream and yogurt were examined for isolation, identification and molecular identification of Listeria spp. Extraction of natural plant extract as clove, thyme and pomegranate peels and detection of their inhibitory effect on Listeria spp. Results: The prevalence of Listeria spp. in milk was 36% where 14% as L. monocytogenes, 6% L. innocua and 16% and other Listeria spp. was 16%. In yogurt, Listeria spp. was 6% as L. innocua was 2% and other Listeria spp. was 4%, while no L. monocytogenes was detected. In ice cream, Listeria spp. was 8% where L. monocytogenes was 2% and other Listeria spp. was 6% while no L. innocua was detected. The concentration of plant extract was 2.5% which showed high reduction rate on L. innocua and L. monocytogenes during shelf life of soft cheese. Conclusion and clinical relevance: Listeria is widely isolated from milk than from ice cream and yogurt. Plant extracts play role in food preservation and consider as a natural antimicrobial agent where most effective one was clove extract.

scholarly journals Prevalence and Characterization of Listeria Species from Raw Milk and Dairy Products from Çanakkale Province

2018 ◽  
Vol 6 (1) ◽  
pp. 61 ◽  
Author(s):  
Pınar Şanlıbaba ◽  
Başar Uymaz Tezel
Keyword(s):  
Listeria Monocytogenes ◽  
Raw Milk ◽  
Common Species ◽  
Food Samples ◽  
Pasteurized Milk ◽  
Listeria Species ◽  
Test Kit ◽  
White Cheese ◽  
Listeria Welshimeri

The objective of this study was to determine the prevalence of Listeria species, specifically Listeria monocytogenes, in raw milk, pasteurized milk, white cheese, and homemade cheese. A total of 200 food samples were collected and analyzed to examine the presence of Listeria spp. The EN ISO 11290-1 method was used for isolation of Listeria. API Listeria test kit was used for biochemically characterization. Listeria spp. were isolated in 25 of the 200 samples (12.5%). The largest number of Listeria spp. was detected in homemade cheese (24%), followed by raw milk (18%), and white cheese (8%). Listeria spp. were not isolated from the pasteurized milk. The most common species isolated were Listeria innocua (5.5%); the remaining Listeria isolates were Listeria ivanovi (3.5%), Listeria welshimeri (3%), and Listeria monocytogenes (0.5%). Listeria monocytogenes was detected in only raw milk.

Phylogeny Characterization of Seb Gene Encoding Enterotoxins in Staphylococcus aureus Isolated from Raw Milk and Cheese

2019 ◽  
Vol 9 (o3) ◽  
Author(s):  
Fatima N. Aziz ◽  
Laith Abdul Hassan Mohammed-Jawad
Keyword(s):  
Staphylococcus Aureus ◽  
Food Poisoning ◽  
Raw Milk ◽  
Staphylococcal Enterotoxin B ◽  
Human Pathogen ◽  
Conventional Pcr ◽  
Biochemical Tests ◽  
Specific Primers ◽  
Gene Encoding

Food poisoning due to the bacteria is a big global problem in economically and human's health. This problem refers to an illness which is due to infection or the toxin exists in nature and the food that use. Milk is considered a nutritious food because it contains proteins and vitamins. The aim of this study is to detect and phylogeny characterization of staphylococcal enterotoxin B gene (Seb). A total of 200 milk and cheese samples were screened. One hundred ten isolates of Staphylococcus aureus pre-confirmed using selective and differential media with biochemical tests. Genomic DNA was extracted from the isolates and the SEB gene detects using conventional PCR with specific primers. Three staphylococcus aureus isolates were found to be positive for Seb gene using PCR and confirmed by sequencing. Sequence homology showed variety range of identity starting from (100% to 38%). Phylogenetic tree analyses show that samples (6 and 5) are correlated with S. epidermidis. This study discovered that isolates (A6-RLQ and A5-RLQ) are significantly clustered in a group with non- human pathogen Staphylococcus agnetis.

Characterization of Venoms of Deinagkistrodon acutus and Bungarus multicinctus Using Proteomics and Peptidomics

2020 ◽  
Vol 17 (3) ◽  
pp. 241-254
Author(s):  
Yaqiong Zhang ◽  
Zhiping Jia ◽  
Yunyang Liu ◽  
Xinwen Zhou ◽  
Yi Kong
Keyword(s):  
Snake Venom ◽  
Protein Families ◽  
Traditional Medicines ◽  
Phospholipases A2 ◽  
Inhibitory Peptides ◽  
Sds Page ◽  
Deinagkistrodon Acutus ◽  
Venom Proteins ◽  
Proteins And Peptides

Background: Deinagkistrodon acutus (D. acutus) and Bungarus multicinctus (B. multicinctus) as traditional medicines have been used for hundreds of years in China. The venoms of these two species have strong toxicity on the victims. Objective: The objective of this study is to reveal the profile of venom proteins and peptides of D. acutus and B. multicinctus. Method: Ultrafiltration, SDS-PAGE coupled with in-gel tryptic digestion and Liquid Chromatography- Electrospray Ionization-Tandem Mass Spectrometry (LC-ESI-MS/MS) were used to characterize proteins and peptides of venoms of D. acutus and B. multicinctus. Results: In the D. acutus venom, 67 proteins (16 protein families) were identified, and snake venom metalloproteinases (SVMPs, 38.0%) and snake venom C-type lectins (snaclecs, 36.7%) were dominated proteins. In the B. multicinctus venom, 47 proteins (15 protein families) were identified, and three-finger toxins (3FTxs, 36.3%) and Kunitz-type Serine Protease Inhibitors (KSPIs, 32.8%) were major components. In addition, both venoms contained small amounts of other proteins, such as Snake Venom Serine Proteinases (SVSPs), Phospholipases A2 (PLA2s), Cysteine-Rich Secreted Proteins (CRISPs), 5'nucleotidases (5'NUCs), Phospholipases B (PLBs), Phosphodiesterases (PDEs), Phospholipase A2 Inhibitors (PLIs), Dipeptidyl Peptidases IV (DPP IVs), L-amino Acid Oxidases (LAAOs) and Angiotensin-Converting Enzymes (ACEs). Each venom also had its unique proteins, Nerve Growth Factors (NGFs) and Hyaluronidases (HYs) in D. acutus, and Cobra Venom Factors (CVFs) in B. multicinctus. In the peptidomics, 1543 and 250 peptides were identified in the venoms of D. acutus and B. multicinctus, respectively. Some peptides showed high similarity with neuropeptides, ACE inhibitory peptides, Bradykinin- Potentiating Peptides (BPPs), LAAOs and movement related peptides. Conclusion: Characterization of venom proteins and peptides of D. acutus and B. multicinctus will be helpful for the treatment of envenomation and drug discovery.

Characterization of Glycoprotein Fraction from Carp Pituitaries Isolated Using Concanavalin A as the Affinity Ligand

1998 ◽  
Vol 63 (3) ◽  
pp. 434-440 ◽  
Author(s):  
Irena Hulová ◽  
Jana Barthová ◽  
Helena Ryšlavá ◽  
Václav Kašička
Keyword(s):  
Concanavalin A ◽  
Reversed Phase ◽  
Amino Acid Sequences ◽  
Gel Chromatography ◽  
Affinity Ligand ◽  
Sds Page ◽  
Terminal Amino ◽  
Α And Β Subunits

Glycoproteins that have affinity to Concanavalin A were isolated from the acetone-dried pituitaries of common carp (Cyprinus carpio L.). Two fractions of glycoproteins were separated using gel chromatography on Superdex 75HR. The fraction with lower molecular weight (30 000) corresponding to the carp gonadotropin cGtH II was composed of two subunits as determined using SDS-PAGE. This protein fraction was further divided into four components using reversed-phase HPLC. Two fractions were pure α and β subunits of cGtH II as follows from immunodetection and from determination of N-terminal amino acid sequences. The other two were a mixture of α and β subunits as was also revealed by N-terminal analysis. Capillary electrophoresis was also used for characterization of isolated glycoproteins.

Characterization of a novel theta-type plasmid pSM409 of Enterococcus faecium RME isolated from raw milk

Gene ◽  
2021 ◽  
Vol 777 ◽  
pp. 145459
Author(s):  
Tawsif Ahmed Kazi ◽  
Suranjita Mitra ◽  
Bidhan Chandra Mukhopadhyay ◽  
Sukhendu Mandal ◽  
Swadesh Ranjan Biswas
Keyword(s):  
Enterococcus Faecium ◽  
Raw Milk

scholarly journals Study on cocoonase, sericin, and degumming of silk cocoon: computational and experimental

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Preeti Anand ◽  
Jay Prakash Pandey ◽  
Dev Mani Pandey
Keyword(s):  
San Francisco ◽  
Tertiary Structure ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Evolutionary Genetics ◽  
Imaging Analysis ◽  
Silk Cocoon ◽  
Natural Color ◽  
Sds Page

Abstract Background Cocoonase is a proteolytic enzyme that helps in dissolving the silk cocoon shell and exit of silk moth. Chemicals like anhydrous Na2CO3, Marseille soap, soda, ethylene diamine and tartaric acid-based degumming of silk cocoon shell have been in practice. During this process, solubility of sericin protein increased resulting in the release of sericin from the fibroin protein of the silk. However, this process diminishes natural color and softness of the silk. Cocoonase enzyme digests the sericin protein of silk at the anterior portion of the cocoon without disturbing the silk fibroin. However, no thorough characterization of cocoonase and sericin protein as well as imaging analysis of chemical- and enzyme-treated silk sheets has been carried out so far. Therefore, present study aimed for detailed characterization of cocoonase and sericin proteins, phylogenetic analysis, secondary and tertiary structure prediction, and computational validation as well as their interaction with other proteins. Further, identification of tasar silkworm (Antheraea mylitta) pupa stage for cocoonase collection, its purification and effect on silk sheet degumming, scanning electron microscope (SEM)-based comparison of chemical- and enzyme-treated cocoon sheets, and its optical coherence tomography (OCT)-based imaging analysis have been investigated. Various computational tools like Molecular Evolutionary Genetics Analysis (MEGA) X and Figtree, Iterative Threading Assembly Refinement (I-TASSER), self-optimized predicted method with alignment (SOPMA), PROCHECK, University of California, San Francisco (UCSF) Chimera, and Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) were used for characterization of cocoonase and sericin proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), protein purification using Sephadex G 25-column, degumming of cocoon sheet using cocoonase enzyme and chemical Na2CO3, and SEM and OCT analysis of degummed cocoon sheet were performed. Results Predicted normalized B-factors of cocoonase and sericin with respect to α and β regions showed that these regions are structurally more stable in cocoonase while less stable in sericin. Conserved domain analysis revealed that B. mori cocoonase contains a trypsin-like serine protease with active site range 45 to 180 query sequences while substrate binding site from 175 to 200 query sequences. SDS-PAGE analysis of cocoonase indicated its molecular weight of 25–26 kDa. Na2CO3 treatment showed more degumming effect (i.e., cocoon sheet weight loss) as compared to degumming with cocoonase. However, cocoonase-treated silk cocoon sheet holds the natural color of tasar silk, smoothness, and luster compared with the cocoon sheet treated with Na2CO3. SEM-based analysis showed the noticeable variation on the surface of silk fiber treated with cocoonase and Na2CO3. OCT analysis also exemplified the variations in the cross-sectional view of the cocoonase and Na2CO3-treated silk sheets. Conclusions Present study enlightens on the detailed characteristics of cocoonase and sericin proteins, comparative degumming activity, and image analysis of cocoonase enzyme and Na2CO3 chemical-treated silk sheets. Obtained findings illustrated about use of cocoonase enzyme in the degumming of silk cocoon at larger scale that will be a boon to the silk industry.

scholarly journals Comparative Analysis of Electrophoretic Profile of Major Proteins of Milk from Alpine and Carpathian Goats

2017 ◽  
Vol 74 (1) ◽  
pp. 20 ◽  
Author(s):  
Alina NASALEAN ◽  
Laurentiu OGNEAN ◽  
Sergiu MUNTEAN ◽  
Stefana BALICI ◽  
Horea MATEI
Keyword(s):  
Protein Profile ◽  
Milk Proteins ◽  
Goat Milk ◽  
Protein Composition ◽  
Raw Milk ◽  
Biologically Active ◽  
Protein Fractions ◽  
Animal Nutrition ◽  
Sds Page ◽  
Percentage Data

The milk’s proteins provide nutritional and biologically active values, essential in human and animal nutrition. In the case of goat milk, the proteins’ concentration and quality represent basic indices for the evaluation of the nutritional and biologically active values. The proposal is to comparatively analyse the protein profile of milk. The milk was collected from two different breeds: French Alpine and Romanian Carpathian. During March and April 2016 there were collected samples of raw milk in hygienic and sanitation conditions. There were two lots: first lot has 10 Carpathian goats and the second lot has 10 Alpine goats. The protein composition of goat milk was established with SDS-PAGE, after the evaluation of the total proteins’ concentration with the Bradford method. The quantitative and percentage data obtained with electrophoresis revealed few differences between those 8 identified protein fractions. Between those two lots, regarding the levels of β-CN, k-CN and β-lactoglobulines there were significant differences. The other protein fractions have values almost identical. Statistical analysis of obtained data shaped the differences in the protein profile at those two breeds. Based on those differences it is to note the superior potential of the Alpine breed regarding the content in biologically active milk proteins. Regarding the obtained data, this study brings new contributions for the evaluation and analysis of protein profile as a nutritive and biologically active component of goat milk, confirming its character as a functional aliment.

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