Natural antimicrobial and antioxidant substances and their

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studied as phytochemical bioactive compounds Pediococcus and Streptococcus Saccharomyces. specially about their antioxidant and antimicrobial and Aspergillus 22 25 26 28. activities 14 Lactococcus lactis used in this work is a. The presence of antioxidants in spices cannot be a homofermentative bacterium 27 This species is a. surprise since more than 5 000 years ago ancient lactic acid bacterium that is Generally Recognised. Egyptians used them in their everyday routine not as Safe by the US Food and Drug Administration 27 29. only in food as also in medical cares Rosemary Some of its advantageous characteristics are. sage and oregano were demonstrated in some thermostability viability at a wide pH range and. studies to have a high phenolic content which works antimicrobial properties especially against. as antioxidant 15 Clove and coneflower extracts pathogenic bacteria Escherichia coli and Candida. showed good results for antioxidant activity with 46 7 albicans The production of lactic acid bacteriocins. and 45 6 mg of trolox equivalent g mg TE g nisin considered as natural food preservative and. respectively 4 In an article published by Arora and hydrogen peroxide might be a competitive behaviour. Kaur 1999 16 garlic ajwain black pepper clove against those bacteria 25 30 32. ginger cumin and caraway are examples of plants From all known techniques soxhlet and supercritical. with antibacterial effect against gram positive and or fluid extraction are the most used to extract. gram negative bacteria Other research work antioxidant from plants Ultrasound assisted. revealed that clove extracts have an antioxidant extraction is an efficient extraction technique in. activity comparable to synthetic antioxidants laboratory yet the same is not verified at industrial. Interesting results were also obtained from blending scale 3 7 33 34 Although conventional soxhlet. different spices extracts There was an improvement extraction is a very simple technique the use of large. of antioxidant and antibacterial activities when clove amounts of solvents acetate methanol ethanol or. and oregano extracts were combined in comparison water and the impossibility of extraction of thermo. with pure extracts 17 susceptible compounds are its biggest. Whey was traditionally seen as a waste product from disadvantage 3 7. milk processing 18 However its consumption has Encapsulation is used to avoid the direct contact. increased due to its health benefits including the between the substances and the product they are. prevention of cardiovascular disease and being added to reducing in some cases its toxicity. osteoporosis More advantages of whey are related and grant a controlled release of these compounds. with its antimicrobial activity through lactoferrin Encapsulation in nanoparticles has some. immunologic modulation and improvement of muscle advantages as their controllable size usually ranging. strength 18 20 In fact nowadays whey protein is well from 1 to 100 nm which leads a sizeable surface. known in the society especially by athletes and is area to mass ratio and high reactivity structures. consumed as a dietary protein supplement Nanoparticles can be divided in liposomes. Probiotics are living microorganisms which when polymeric nanocrystals and solid lipid nanoparticles. administered in adequate amounts confers health Liposomes are lipid vesicles composed by. benefits on the host 21 25 In food probiotics have cholesterol and phospholipids usually from soya. shown many health benefits taking an important role bean lecithin due to its safety and are availability at a. in fight against gastrointestinal diseases in relatively low cost There are many possible. maintaining a good balance and composition of methods that can be used in their preparation such. intestinal flora in reducing cholesterol levels and in as ethanol injection thin film evaporation and. showing an anti carcinogenic activity 22 25 26 As a ultrasonication Low encapsulation efficiency high. matter of fact food products containing probiotics manufacturing costs degradation by hydrolysis or. have been used for longer than it is believed The oxidation sedimentation aggregation or fusion. best examples are dairy products such as ice cream during storage are pointed as disadvantages 4 35 37. cheese milk powder and yogurts 22 The biggest Since probiotics belong to micrometre scale they. problem in include probiotics in products is to would not fit inside nanoparticles Alginate chitosan. guarantee the right dosage at the time the product is gelatine carrageenan cellulose or maize starch are. consumed The processing and storage until its examples of polymers that have been used in their. consumption might interfere with the viability of encapsulation 38 Alginate chitosan and starch. probiotics due to high temperatures and or oxygen particles can be prepared by the emulsification. content mechanical shearing dehydration and method which is based on gelation and cross linking. osmotic pressure 22 25 27 Two possible solutions pass of polymers Chitosan particles are polycationic and. though improving the resistance of probiotics for that allows for an interaction with microbial cell walls. instance by encapsulating them and modifying the which are negatively charged This interaction. production and storage of these products 22 Another causes an osmotic destabilisation that can lead to. challenge is related with the fact that probiotics have membrane disruption Chitosan can also bind to. to be capable of surviving the digestive system microbial DNA and inhibit mRNA and protein. conditions in particular the low pH in the stomach 27 synthesis 4. Besides the mostly common species used in food,Chitosan is more expensive than alginate and. Lactobacillus and Bifidobacterium other, because of that its application is limited to cosmetic. microorganisms are also used Bacillus,industry while in food products might not be. Enterococcus Lactococcus Leuconostoc, profitable Alginate is cheaper and due to their a cooling system for 1 min Prepared particles were. stability can be applied in food however its big size stored at 7 C Liposomes were centrifuged at 11 000. is not suitable in cosmetic products Adding some of rpm for 1 hour and total phenolic and flavonoid. these active substances in their products can be an content were measured from supernatant. opportunity in the food cosmetic and pharmaceutical Total phenolic content. industries The wine industry had shown some, In the Folin Ciocalteu colorimetric method 1 mL 10.
interest in phenolic compounds because they can,Folin ciocalteu solution in water Penta Chemicals. give particular characteristics such as colour and. 50 L sample and 1 mL distilled water were mixed,flavour 3 Consumers have been showing a. and left for 5 minutes 1 mL saturated sodium,preference for natural products including. carbonate solution Lach Ner was added the, antioxidants and antibacterial agents over synthetic. solution was mixed and left for 15 min before the read. the main reasons being safety concerns and the,of absorbance at 750 nm in an UV Vis.
reduction of synthetic food additives used In,spectrophotometer Boeco Germany model S 220. addition natural antioxidants embrace health, using one 1 cm light path cuvette Quantification of. benefits resulting in an increased demand for clean. total phenolic content was made using a standard,label products 2 15 3 31 32. curve of Gallic acid Sigma Aldrich, In this work total phenolic and flavonoid content was. Total flavonoid content, measured from extractions under different conditions.
from 11 spices and herbs cinnamon pepper ginger In the aluminium chloride colorimetric method 0 5. clove oregano star anise nutmeg mace guarana mL of sample was mixed with 1 5 mL distilled water. green and black tea Whey and purified fractions and 0 2 mL sodium nitrite Lach Ner and left for 5. were also assayed regarding their antimicrobial min 0 2 mL aluminium chloride Lach Ner mixed. activity allowing for the selection of the best and left for 5 minutes afterwards 1 mL distilled water. purification method among those tested for this and 1 5 mL sodium hydroxide Lach Ner were. particular use Lactococcus lactis was used as a added and left for 15 min before the read of. probiotic Encapsulated and non encapsulated absorbance at 510 nm using an UV Vis. extracts alone or co encapsulated with the probiotic spectrophotometer Quantification was made using a. agent were tested regarding both their antioxidant standard curve of catechin Sigma Aldrich. and antimicrobial activities Antioxidant activity, MATERIALS AND METHODS ABTS was dissolved in water to a concentration of 7. mM ABTS stock solution The ABTS radical cation, Extractions was prepared by the reaction of the stock solution. Extracts were prepared from a selection of eleven with 2 45 mM potassium persulfate Sigma Aldrich. herbs and spices using either distilled water or and kept in the dark for 12 16 h before use This. ethanol Lach Ner at different concentrations 30 solution was diluted with ethanol until reaching an. 50 80 as solvents Those herbs and spices absorbance of 0 70 at 734 nm For 10 L of each. were bought from the local market in Brno Czech sample to time zero liquid used in the extraction 1. Republic The extraction mixtures were prepared at mL of ABTS radical cation was added and after. a concentration of 0 01 g mL and incubated at 37 C exactly 10 min the absorbance at the same wave. for 15 min or 24 h according the extraction time length was read Antioxidant activity was determined. under study These were filtered through using the calibration curve obtained with Trolox. cheesecloth or for small particles cinnamon and Sigma Aldrich. ginger centrifuged Hermle Labortechnik GmbH Sugars. model Z 36 HK for 2 min at 11 000 rpm Sugar content from whey samples was measured by. Encapsulations high performance liquid chromatography HPLC. Polysaccharide particles were prepared through the operated on a Thermo Scientific system equipped. emulsification method using Buchi Encapsulator B with RI detector Analysis was carried out at a. 395 Pro with a 450 m nozzle Alginate particles temperature of 60 C using a Phenomenex C18. were prepared by spraying a mixture of 10 mL 2 column of Rezex ROA SVBD 300 x 7 8 mm 20 L. sodium alginate Sigma Aldrich 5 mL distilled water of sample were injected onto the column Elution was. and 5 mL extract to 60 mL calcium chloride solution carried out for 15 min at a flow rate of 1 mL min using. Lach Ner Chitosan particles were prepared with 10 5 mM of H2SO4 as the mobile phase Data were. mL 2 chitosan Sigma Aldrich 5 mL distilled water evaluated through the Chromeleon programme. and 5 mL extract sprayed in 60 mL of Sodium Lactic acid. tripolyphosphate Sigma Aldrich After the formation Lactic acid content was also determined by HPLC. of particles they were filtered using filter Before injection the sample was centrifuged at 7 000. paper Liposome particles were prepared using an rpm for 10 min and filtered through a 45 m filter. ultrasonic homogeniser Bandelin ssonopuld LUT Syringe Filters Nylon Sigma Aldrich 13 mm. ultrasonic homogeniser 20 0 mg of cholesterol 45 m The chromatography was performed at 60. Sigma Aldrich 180 mg of soya bean lecithin C on a Thermo Fisher Scientific system Ultimate. SERVA and 10 mL of the extract were sonicated 3000 HPLC with PDA detection at 205 nm and using. 80 W 20 kHz inside a cold water bath working as a C18 Rezex ROA SVBD column 300 x 7 8 mm 20. mL were eluted at 1 mL min The results were culture suspension for 5 min at 5 000 rpm Cells were. analysed using the Chromeleon programme stained with 5 L of propidium iodide 1 mg 1 mL. Total proteins H2O per mL of sample, Protein content was determined using the Hartree Statistical analysis. Lowry Assay a spectrophotometric method The All tests were performed at least in triplicate. calibration curve was obtained with bovine serum Statistical analysis was carried out with Excel or. albumin Sigma Aldrich GraphPad Prism 6 Results are expressed as mean. SDS PAGE electrophoresis standard deviation, Molecular weight of proteins present in the samples RESULTS AND DISCUSSION. was estimated by SDS PAGE,Characterisation of herbs and spices extracts.
Size and stability of particles,Extractions were performed in aqueous phase and. Size and stability zeta potential were measured in with 30 50 and 80 ethanol solutions during 15. Malver Zetasizer Nano ZS equipment Stability assay min and 24 h Results obtained to total phenolic. used a surface zeta potential accessory Particles TPC total flavonoid content TFC and antioxidant. size were measured by dynamic light scattering activity AA of extractions are illustrated in Figure 1. Long term stability of particles in digestive fluids Flavonoids are included in the different classes of. Firstly 0 2 g of particles were weighted added to 1 polyphenols Although it is expected that samples. mL of stomach fluid and incubated at 37 C for 20 have a higher content of total polyphenols than total. min From this solution 0 5 mL were taken to flavonoids this comparison cannot be done directly. measure the TPC To the remaining 0 5 mL still with TPC is measured in mg of gallic acid equivalent and. the particles 0 25 mL of the pancreatic fluid and 0 25 TFC in mg of catechin thus not covering the whole. mL of the bile fluid were added and incubated at 37 range of polyphenols and flavonoids respectiv. Antimicrobial agents are used to control and if possible eliminate pathogenic microorganisms They can be natural synthetic or semi synthetic In the food industry antimicrobial agents are important especially as preservatives 8 9 The mechanisms of action of antimicrobial agents have not yet been thoroughly studied The disturbance of cell

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