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1.
Lett Appl Microbiol ; 75(5): 1203-1214, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35862481

ABSTRACT

Alicyclobacillus acidoterrestris can cause spoilage in orange juice that leads to consumer rejection. Six different orange juices were physiochemically characterized (pH, total soluble solids, titratable acidity, total polyphenols and vitamin C). A bottle for each sampling point per juice was filled (headspace: 40% volume) and inoculated with 102 -103 CFU per ml of A. acidoterrestris ATCC® 49025™ (heat shocked before inoculation: 75°C, 20 min). Samples were stored for 21 days at 45 ± 1°C and plate counted periodically on acidified YSG agar (pH 3·7) incubated at 45 ± 1°C for 3 days. The effect of headspace (6% versus 40% volume) on A. acidoterrestris growth was also evaluated. The effect of nisin (0·006, 0·003, 0·0015, and 0·00075%), sodium benzoate (0·1%), potassium sorbate (0·1%) and a mix of benzoate and sorbate (0·05% each) on A. acidoterrestris was additionally addressed. Alicyclobacillus acidoterrestris reached up to 107 CFU per ml in five of the six juices in less than 1 week. Headspace significantly impacted (P < 0·05) A. acidoterrestris maximum population, which reached the critical value of 5 log CFU per ml at 40% headspace. All preservatives, regardless of concentration, showed a bacteriostatic effect during 22 days of storage with no significant differences amongst treatments (P > 0·05).


Subject(s)
Anti-Infective Agents , Citrus sinensis , Nisin , Nisin/pharmacology , Agar/chemistry , Sorbic Acid , Sodium Benzoate , Beverages , Spores, Bacterial , Anti-Infective Agents/pharmacology , Ascorbic Acid/pharmacology
2.
Food Chem ; 335: 127576, 2021 Jan 15.
Article in English | MEDLINE | ID: mdl-32739805

ABSTRACT

The main causes of food spoilage come from the process of oxidation and the contamination by microorganisms. For the purpose of increasing food shelf-life the industries employ different techniques, being the addition of preservatives, one of the most used. The aim of this contribution was to investigate the potential antioxidant properties of tyrosol (4-hydroxyphenethyl alcohol, 4-OH) and tyrosol derived isomers (2-hydroxyphenethyl alcohol, 2-OH and 3-hydroxyphenethyl alcohol, 3-OH) against reactive oxygen species (ROS) and the antimicrobial effect on Staphylococcus aureus and Escherichia coli. Furthermore, the type of antioxidant effect of substrates and commercial antioxidants mixtures was studied. Upon visible-light, the substrates interacted with the vitamin B2 and different ROS were generated. All the compounds deactivated O2(1Δg) and O2●-, whereas only 2-OH and 3-OH inhibited H2O2 and HO●. The substrates exhibited a synergistic antioxidant effect when combined with commercial antioxidants. 2-OH showed antimicrobial activity against strains tested.


Subject(s)
Food Additives/pharmacology , Phenylethyl Alcohol/analogs & derivatives , Riboflavin/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Antioxidants/chemistry , Antioxidants/pharmacology , Drug Synergism , Hydrogen Peroxide/chemistry , Hydroxyl Radical/chemistry , Phenylethyl Alcohol/chemistry , Phenylethyl Alcohol/pharmacology
3.
Front Psychiatry ; 9: 14, 2018.
Article in English | MEDLINE | ID: mdl-29459833

ABSTRACT

After 25 years of its discovery in the rat brain, d-serine is a recognized modulator of synaptic plasticity and cognitive processes through its actions on the NMDA-glutamate receptor. Importantly, cognitive impairment is a core feature of conditions, such as schizophrenia, Alzheimer's disease, depression, and aging, and is associated to disturbances in NMDA-glutamate receptors. The d-serine pathway has been associated with cognitive deficits and these conditions, and, for this reason, d-serine signaling is subject of intense research to probe its role in aiding diagnosis and therapy. Nevertheless, this has not resulted in new therapies being incorporated into clinical practice. Therefore, in this review we will address many questions that need to be solved by future studies, regarding d-serine pharmacokinetics, possible side effects, other strategies to modulate its levels, and combination with other therapies to increase its efficacy.

4.
Mater Sci Eng C Mater Biol Appl ; 56: 545-54, 2015 Nov 01.
Article in English | MEDLINE | ID: mdl-26249626

ABSTRACT

This work was focused on: i) developing single and blend films based on carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVOH) studying their properties, ii) analyzing the interactions between CMC and PVOH and their modifications UV-induced in the presence of sodium benzoate (SB), and iii) evaluating the antimicrobial capacity of blend films containing SB with and without UV treatment. Once the blend films with SB were exposed to UV radiation, they exhibited lower moisture content as well as a greater elongation at break and rougher surfaces compared to those without treatment. Considering oxygen barrier properties, the low values obtained would allow their application as packaging with selective oxygen permeability. Moreover, the characteristics of the amorphous phase of the matrix prevailed with a rearrangement of the structure of the polymer chain, causing a decrease of the crystallinity degree. These results were supported by X-rays and DSC analysis. FT-IR spectra reflected some degree of polymer-polymer interaction at a molecular level in the amorphous regions. The incorporation of sodium benzoate combined with UV treatment in blend films was positive from the microbial point of view because of the growth inhibition of a wide spectrum of microorganisms. From a physicochemical perspective, the UV treatment of films also changed their morphology rendering them more insoluble in water, turning the functionalized blend films into a potential material to be applied as food packaging.


Subject(s)
Carboxymethylcellulose Sodium/chemistry , Membranes, Artificial , Polyvinyl Alcohol/chemistry , Sodium Benzoate/chemistry , Ultraviolet Rays , Anti-Infective Agents/chemistry , Candida/growth & development , Escherichia coli/growth & development , Penicillium/growth & development , Salmonella/growth & development
5.
Braz. j. microbiol ; Braz. j. microbiol;44(4): 1133-1137, Oct.-Dec. 2013. graf
Article in English | LILACS | ID: lil-705257

ABSTRACT

Alicyclobacillus acidoterrestris is considered to be one of the important target microorganisms in the quality control of acidic canned foods. There is an urgent need to develop a suitable method for inhibiting or controlling the germination and outgrowth of A.acidoterrestris in acidic drinks. The aim of this work was to evaluate the chemicals used in the lemon industry (sodium benzoate, potassium sorbate), and lemon essential oil as a natural compound, against a strain of A.acidoterrestris in MEB medium and in lemon juice concentrate. The results pointed out that sodium benzoate (500-1000-2000 ppm) and lemon essential oil (0.08- 0.12- 0.16%) completely inhibited the germination of A. acidoterrestris spores in MEB medium and LJC for 11 days. Potassium sorbate (600-1200 ppm) was more effective to inhibit the growth of the microbial target in lemon juice than in MEB medium. The effect of sodium benzoate, potassium sorbate and essential oil was sporostatic in MEB and LJC as they did not affect spore viability.


Subject(s)
Alicyclobacillus/drug effects , Alicyclobacillus/physiology , Anti-Bacterial Agents/pharmacology , Citrus/chemistry , Microbial Viability/drug effects , Oils, Volatile/pharmacology , Anti-Bacterial Agents/isolation & purification , Culture Media/chemistry , Oils, Volatile/isolation & purification , Sodium Benzoate/pharmacology , Spores, Bacterial/drug effects , Spores, Bacterial/physiology
6.
GEN ; 67(1): 11-15, mar. 2013. ilus, tab
Article in Spanish | LILACS | ID: lil-681064

ABSTRACT

La hiperamonemia se presenta en forma secundaria por aumento en la producción de amonio, como en la hemorragia gastrointestinal o disminución de la eliminación, como ocurre en errores innatos del metabolismo, principalmente en aquellos con defectos en el ciclo de la urea, insuficiencia hepática o fármacos. Clasificar la hiperamonemia y reportar las opciones terapéuticas en niños, su abordaje clínico y revisión de la literatura. Estudio prospectivo, descriptivo y transversal de niños con hiperamonemia. Variables: edad, género, etiología, niveles de amonio, clínica, tratamiento. 21 pacientes, 12 (57,12%) varones y 9 (42,88%) hembras. Edad promedio 3,91 años (rango:<1mes-14 años). Amonio promedio general 214,66 mmol/l (rango:110-980), clasificados según severidad: sin insuficiencia hepática 11/21 con promedio de amonio 99,44 y 201 mmol/l en hiperamonemia leve y moderada respectivamente. Clínica y laboratorio de insuficiencia hepática en 10/21 con promedio de amonio de 114,44, 287,51 y 756,66 en leve, moderada y severa hiperamonemia, con una diferencia significativa entre el nivel de amonio y la presencia o ausencia de insuficiencia hepática (p<0,0001); 5/10 con insuficiencia hepática ingresaron a terapia intensiva, 4 de ellos presentaron encefalopatía hepática, un paciente fallecido. Etiología: Error innato del metabolismo 33,33%, toxicidad por medicamentos 23,80%, hepatitis viral A fulminante 19,04% y otros virus 9,52%, hepatitis autoinmune 4,76% y urosepsis 4,76%. En los casos leves-moderados se administró lactulosa dosis respuesta vía oral 19/21 y por enema rectal 7/21 con L-carnitina en 15/21 y en Hiperamonemia severa adicionalmente Benzoato de sodio en 4/21 y hubo indicación de hemodiálisis en 3 pacientes. Restricción proteica en todos, vitaminoterapia y 6 niños tratados con ácido ursodeoxicólico. La hiperamonemia es multifactorial, requiere diagnóstico temprano, la clasificación de severidad permite el tratamiento oportuno para evitar complicaciones....


Hyperammonaemia occurs secondarily by increased production of ammonia, as gastrointestinal bleeding or decreased elimination, as occurs in inborn errors of metabolism, especially in those with defects in the urea cycle, liver failure or drugs. To classify the report hyperammonaemia and therapeutic options in children, its clinical approach and review of the literature. Prospective, descriptive and transversal children with hyperammonaemia. Variables: age, gender, etiology, ammonia levels, clinical treatment. 21 patients, 12 (57,12%) males and 9 (42,88%) females. Mean age 3,91 years (range: <1m-14a). ammonium 214,66 mmol / l (range :110-980), classified according to severity: no hepatic impairment 11/21 with 99,44 average ammonium and 201 mmol / l in Hyperammoanemia mild and moderate respectively. Clinical and laboratory liver failure 10/21 with ammonium averaging 114,44, 287,51 and 756,66 as mild, moderate and severe hyperammonemia, with a significant difference between the level of ammonia and the presence or absence of liver failure (p < 0,0001), 5/10 with liver failure admitted to intensive care, 4 of them had hepatic encephalopathy, a patient died. Etiology: An inborn error of metabolism 33,33%, 23,80% drug toxicity, fulminant viral hepatitis and other viruses 19,04% 9,52% 4,76% autoimmune hepatitis and urosepsis 4,76%. In mild-moderate cases were given oral lactulose Dose 19/21 and by enema rectal 7/21 with L-carnitine in 15/21 and further severe Hyperammonemia sodium benzoate 4/21 and was indication of hemodialysis in 3 patients. Protein restriction at all, vitamin therapy and 6 children treated with ácidoursodeoxicólico. Hyperammonemia is multifactorial, requires early diagnosis, classification of severity allows early treatment to avoid complications and development of irreversible neurological sequelae


Subject(s)
Female , Child , Sodium Benzoate/therapeutic use , Carnitine/therapeutic use , Hepatic Encephalopathy , Hyperammonemia/diagnosis , Hyperammonemia/therapy , Hepatic Insufficiency/pathology , Lactulose/therapeutic use , Gastroenterology , Pediatrics
7.
Braz J Microbiol ; 44(4): 1133-7, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24688502

ABSTRACT

Alicyclobacillus acidoterrestris is considered to be one of the important target microorganisms in the quality control of acidic canned foods. There is an urgent need to develop a suitable method for inhibiting or controlling the germination and outgrowth of A.acidoterrestris in acidic drinks. The aim of this work was to evaluate the chemicals used in the lemon industry (sodium benzoate, potassium sorbate), and lemon essential oil as a natural compound, against a strain of A.acidoterrestris in MEB medium and in lemon juice concentrate. The results pointed out that sodium benzoate (500-1000-2000 ppm) and lemon essential oil (0.08-0.12-0.16%) completely inhibited the germination of A. acidoterrestris spores in MEB medium and LJC for 11 days. Potassium sorbate (600-1200 ppm) was more effective to inhibit the growth of the microbial target in lemon juice than in MEB medium. The effect of sodium benzoate, potassium sorbate and essential oil was sporostatic in MEB and LJC as they did not affect spore viability.


Subject(s)
Alicyclobacillus/drug effects , Alicyclobacillus/physiology , Anti-Bacterial Agents/pharmacology , Citrus/chemistry , Microbial Viability/drug effects , Oils, Volatile/pharmacology , Anti-Bacterial Agents/isolation & purification , Culture Media/chemistry , Oils, Volatile/isolation & purification , Sodium Benzoate/pharmacology , Spores, Bacterial/drug effects , Spores, Bacterial/physiology
8.
Article in English | VETINDEX | ID: vti-444997

ABSTRACT

Alicyclobacillus acidoterrestris is considered to be one of the important target microorganisms in the quality control of acidic canned foods. There is an urgent need to develop a suitable method for inhibiting or controlling the germination and outgrowth of A.acidoterrestris in acidic drinks. The aim of this work was to evaluate the chemicals used in the lemon industry (sodium benzoate, potassium sorbate), and lemon essential oil as a natural compound, against a strain of A.acidoterrestris in MEB medium and in lemon juice concentrate. The results pointed out that sodium benzoate (500-1000-2000 ppm) and lemon essential oil (0.08- 0.12- 0.16%) completely inhibited the germination of A. acidoterrestris spores in MEB medium and LJC for 11 days. Potassium sorbate (600-1200 ppm) was more effective to inhibit the growth of the microbial target in lemon juice than in MEB medium. The effect of sodium benzoate, potassium sorbate and essential oil was sporostatic in MEB and LJC as they did not affect spore viability.

9.
Acta sci. vet. (Online) ; 40(4): 01-04, 2012.
Article in Portuguese | VETINDEX | ID: vti-475707

ABSTRACT

Background: Tissue texture, or tenderness, may be checked-out by analyzing the force necessary to cause muscle fibers rupture (shearing force) and the result is expressed in kilogram-force (kgf). The aim of this paper was to analyze the texture of broiler chicken breast muscles fi xed in a 10% formaldehyde solution and kept in a 0.5% sodium benzoate and 0.5% acetic acid solution up to 180 days so any alteration regarding resistance and the best moment for dissection could be described. Materials, Methods & Results: Forty chicken breasts were used and muscle texture was analyzed by the shearing force whose values were correspondent to the maximum force necessary to chisel the samples. Eight of 40 breasts were taken as a control group (fresh muscles). The remaining breast muscles were fi xed in a 4% formaldehyde solution and kept in plastic containers with this solution during seven days and, then, eight breasts went through texture analysis. The 24 remaining breasts were set in plastic containers with 0.5% sodium benzoate and 0.5% acetic acid solution. The texture analyses were taken out at 30, 90 and 180 days of conservation, and eight breasts were used in each time. The shearing force was obtained for each sample and, just before cutting, muscles were washed in running water for 24 h so the excess of the conservation agent could be removed. Data were submitted to statistic


Background:  Tissue  texture,  or  tenderness,  may  be  checked-out  by  analyzing  the  force  necessary  to  cause  muscle  fibers rupture  (shearing  force)  and  the  result  is  expressed  in  kilogram-force  (kgf).  The  aim  of  this  paper  was  to  analyze  the  texture of  broiler  chicken  breast  muscles  fi  xed  in  a  10%  formaldehyde  solution  and  kept  in  a  0.5%  sodium  benzoate  and  0.5%  acetic acid  solution  up  to  180  days  so  any  alteration  regarding  resistance  and  the  best  moment  for  dissection  could  be  described.Materials,  Methods  &  Results:  Forty  chicken  breasts  were  used  and  muscle  texture  was  analyzed  by  the  shearing  force whose  values  were  correspondent  to  the  maximum  force  necessary  to  chisel  the  samples.  Eight  of  40  breasts  were  taken as  a  control  group  (fresh  muscles).  The  remaining  breast  muscles  were  fi  xed  in  a  4%  formaldehyde  solution  and  kept in  plastic  containers  with  this  solution  during  seven  days  and,  then,  eight  breasts  went  through  texture  analysis.  The  24 remaining  breasts  were  set  in  plastic  containers  with  0.5%  sodium  benzoate  and  0.5%  acetic  acid  solution.  The  texture analyses  were  taken  out  at  30,  90  and  180  days  of  conservation,  and  eight  breasts  were  used  in  each  time.  The  shearing force  was 

10.
Acta sci. vet. (Impr.) ; 40(4): Pub. 1081, 2012. tab
Article in Portuguese | VETINDEX | ID: biblio-1377765

ABSTRACT

Background: Tissue texture, or tenderness, may be checked-out by analyzing the force necessary to cause muscle fibers rupture (shearing force) and the result is expressed in kilogram-force (kgf). The aim of this paper was to analyze the texture of broiler chicken breast muscles fixed in a 10% formaldehyde solution and kept in a 0.5% sodium benzoate and 0.5% acetic acid solution up to 180 days so any alteration regarding resistance and the best moment for dissection could be described. Materials, Methods & Results: Forty chicken breasts were used and muscle texture was analyzed by the shearing force whose values were correspondent to the maximum force necessary to chisel the samples. Eight of 40 breasts were taken as a control group (fresh muscles). The remaining breast muscles were fixed in a 4% formaldehyde solution and kept in plastic containers with this solution during seven days and, then, eight breasts went through texture analysis. The 24 remaining breasts were set in plastic containers with 0.5% sodium benzoate and 0.5% acetic acid solution. The texture analyses were taken out at 30, 90 and 180 days of conservation, and eight breasts were used in each time. The shearing force was obtained for each sample and, just before cutting, muscles were washed in running water for 24 h so the excess of the conservation agent could be removed. Data were submitted to statistical analysis by the 5% Tukey's test. The average shearing force of the control, formaldehyde and 30-day sodium benzoate and acetic acid groups differed among them and from the 90-day and 180-day of sodium benzoate and acetic acid groups. The average shearing forces of the two last groups did not statistically differ among them. Discussion: The longer the muscles were kept in the sodium benzoate and acetic acid solutions, the more they became soft, and the shearing force decreased from 21.46 Kgf (seven days of conservation) to 19.20 Kgf (30 days), 17.23 Kgf (90 days) and 16.32 Kgf (180 days) not reaching, however, values from 8.97 to 15.31 Kgf, as described in chicken breasts conserved in 96oGL ethylic alcohol. The average shearing force of chicken breasts conserved in sodium benzoate and acetic acid progressively decreased during 180 days of conservation, when it reached a value of 16.32 Kgf, similar to the value of 15.32 Kgf of chicken breasts conserved for 45 days in formaldehyde. By the seventh day of conservation in 10% formaldehyde, samples presented an average shearing force of 21.46 Kgf, which was higher than the 15.33 Kgf of chicken breasts conserved during 45 days or the 14.74 to 17.37 Kgf of the same tissue kept up to a year in formaldehyde solution. It was concluded that conservation of breast broiler chickens fixed in formaldehyde and conserved in sodium benzoate and acetic acid made them softer through within 180 days, resulting in a better structure malleability and suggesting that dissection of anatomical muscle pieces may occur in an easier way in this moment. Although the sodium benzoate and acetic acid effect in texture of broiler chicken muscle tissue fixed in formaldehyde has been studied, it is believed that, due this great tissue homogeneity, these data might be taken or used as basis to similar studies in other species.


Subject(s)
Animals , Chickens , Acetic Acid , Sodium Benzoate , Food Preservatives , Formaldehyde , Muscles/drug effects
11.
Acta sci. vet. (Impr.) ; 40(4): 01-04, 2012.
Article in Portuguese | LILACS-Express | VETINDEX | ID: biblio-1457031

ABSTRACT

Background: Tissue texture, or tenderness, may be checked-out by analyzing the force necessary to cause muscle fibers rupture (shearing force) and the result is expressed in kilogram-force (kgf). The aim of this paper was to analyze the texture of broiler chicken breast muscles fi xed in a 10% formaldehyde solution and kept in a 0.5% sodium benzoate and 0.5% acetic acid solution up to 180 days so any alteration regarding resistance and the best moment for dissection could be described. Materials, Methods & Results: Forty chicken breasts were used and muscle texture was analyzed by the shearing force whose values were correspondent to the maximum force necessary to chisel the samples. Eight of 40 breasts were taken as a control group (fresh muscles). The remaining breast muscles were fi xed in a 4% formaldehyde solution and kept in plastic containers with this solution during seven days and, then, eight breasts went through texture analysis. The 24 remaining breasts were set in plastic containers with 0.5% sodium benzoate and 0.5% acetic acid solution. The texture analyses were taken out at 30, 90 and 180 days of conservation, and eight breasts were used in each time. The shearing force was obtained for each sample and, just before cutting, muscles were washed in running water for 24 h so the excess of the conservation agent could be removed. Data were submitted to statistic


Background:  Tissue  texture,  or  tenderness,  may  be  checked-out  by  analyzing  the  force  necessary  to  cause  muscle  fibers rupture  (shearing  force)  and  the  result  is  expressed  in  kilogram-force  (kgf).  The  aim  of  this  paper  was  to  analyze  the  texture of  broiler  chicken  breast  muscles  fi  xed  in  a  10%  formaldehyde  solution  and  kept  in  a  0.5%  sodium  benzoate  and  0.5%  acetic acid  solution  up  to  180  days  so  any  alteration  regarding  resistance  and  the  best  moment  for  dissection  could  be  described.Materials,  Methods  &  Results:  Forty  chicken  breasts  were  used  and  muscle  texture  was  analyzed  by  the  shearing  force whose  values  were  correspondent  to  the  maximum  force  necessary  to  chisel  the  samples.  Eight  of  40  breasts  were  taken as  a  control  group  (fresh  muscles).  The  remaining  breast  muscles  were  fi  xed  in  a  4%  formaldehyde  solution  and  kept in  plastic  containers  with  this  solution  during  seven  days  and,  then,  eight  breasts  went  through  texture  analysis.  The  24 remaining  breasts  were  set  in  plastic  containers  with  0.5%  sodium  benzoate  and  0.5%  acetic  acid  solution.  The  texture analyses  were  taken  out  at  30,  90  and  180  days  of  conservation,  and  eight  breasts  were  used  in  each  time.  The  shearing force  was

12.
Rev. Inst. Adolfo Lutz ; 68(2): 215-223, maio-ago. 2009. tab
Article in Portuguese | LILACS, Sec. Est. Saúde SP, SESSP-CTDPROD, Sec. Est. Saúde SP, SESSP-ACVSES, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: lil-544600

ABSTRACT

Os fungos termorresistentes dos gêneros Byssochlamys, Neosartorya e Talaromyces representam grave problema para a indústria processadora de alimentos, especialmente de frutas e hortaliças, em virtude da ocorrência de ascosporos extremamente resistentes e/ou de micotoxinas termo estáveis. Com o propósito de fornecer subsídios quanto ao uso de quantidades mais racionais de conservantes pela indústria de alimentos e, portanto, tornar seu consumo menos danoso à população, o presente estudo determinou in vitro a concentração mínima de metabissulfito de sódio, benzoato de sódio e sorbato de potássio necessária e suficiente para inibir o crescimento micelial e a germinação de ascósporos de B. fulva, N. fischeri e T.flavus em meio de cultivo acidificado (pH 3,5). Foi demonstrado que metabissulfito de sódio em baixas concentrações é tão eficiente na inibição dos fungos mencionados quanto aos demais conservantes em altas concentrações. Por comparação com os procedimentos utilizados pelas indústrias de alimentos, é possível inferir que estas podem reformular o uso de conservantes, considerando-se o tipo de matéria-prima, a temperatura de processamento, a combinação e concentração efetivamente necessária de aditivos, bem como os efeitos tóxicos desses compostos para a saúde humana.


Subject(s)
Sodium Benzoate , Fungi , Talaromyces
13.
R. Inst. Adolfo Lutz ; 68(1): 49-57, 2009.
Article in Portuguese | VETINDEX | ID: vti-453135

ABSTRACT

Some microorganisms that cause infections are served by processed foods, being removed from them by heat treatment or acidification, while others are difficult to remove and require the use of preservatives. Thus, in the culture medium TSA (trypticase-soya-agar, acidified with citric acid (pH 3.5 and 5.0), it was added specific quantities of sodium metabisulphite (MBS), sodium benzoate (SB) and potassium sorbate (PS). After inoculation with aqueous suspensions (100 L = 104 cells) from Escherichia coli, Bacillus cereus, Salmonella Enteritidis and S. Typhimurium, and incubation for 24-72 h, the number of colony-forming units (CFU) in the cultures was measured to obtain the minimum concentration of each preservative capable of inhibiting (MIC) in vitro the studied isolates, and provide subsidies for their industrial use inappropriate quantities. B. cereus was the isolate more susceptible to MBS, BS and PS (respectively 75, 275and 750 mg.L-1), followed by E. coli (respectively 75, 350 and 1000 mg.L-1). Isolates of Salmonella were the most resistant, and their growth were completely inhibited by 1000 mg BS.L-1, but only reduced by 1250mg PS.L-1. MBS completely inhibited S. Typhimurium to 75 mg.L-1 and S. Enteritidis to 200 mg.L-1.


Alguns micro-organismos causadores de infecções e veiculados por alimentos industrializados são removidos dos mesmos por tratamento térmico ou acidificação, enquanto outros são de difícil eliminação e requerem o uso de conservantes. Assim, acidificou-se meio de cultura TSA (Tripticase-Soja-Agar) com ácido cítrico (pH 3,5 e 5) e acrescentou-se ao mesmo quantidades específicas de metabissulfito de sódio (MBS), benzoato de sódio (BS) e sorbato de potássio (SP). Após inoculação com suspensões aquosas (100L = 104 células) de Escherichia coli, Bacillus cereus, Salmonella Enteritidis e S. Typhimurium, e incubação por 24-72 h, mensurou-se o número de unidades formadoras de colônias (UFC) nos cultivos, visando obter a concentração mínima de cada conservante capaz de inibir (CIM) os isolados estudados in vitro e fornecer subsídios para sua utilização industrial em quantidades apropriadas. B. cereus foi o isolado mais suscetível a MBS, BS e SP (respectivamente 75, 275 e 750 mg.L-1), seguido por E. coli (respectivamente 75, 350 e 1000mg.L-1). Os isolados de Salmonella foram os mais resistentes, sendo seu crescimento completamente inibido por 1000 mg BS.L-1, mas apenas reduzido por 1250 mg SP.L-1. MBS inibiu totalmente S. Typhimurium a75 mg.L-1 e S. Enteritidis a 200 mg.L-1.

14.
R. Inst. Adolfo Lutz ; 68(2): 215-223, 2009.
Article in Portuguese | VETINDEX | ID: vti-452624

ABSTRACT

Heat-resistant fungi of Byssochlamys, Neosartorya and Talaromyces genera represent a serious issue to the food processing industry, especially of fruits and vegetables, due to the occurrence of extremely resistant ascospores and/or heat-stable mycotoxins. In order to provide subsidies to the food industry in using the most rational amounts of preservatives, and to assure the safe consumption of them by the population, this in vitro investigation was conducted to determine the minimum concentrations of sodium metabisulphite, sodium benzoate and potassium sorbate needed to inhibit the mycelial growth of B. fulva, N. fischeri and T.flavus, in acidified (pH 3,5) medium. This study showed that sodium metabisulphite in low concentrations was as much effective in inhibiting the above mentioned fungi as other preservatives in high concentrations. Comparing with the procedures used by the industries, it may be presumed that food manufacturers could reformulate the use of preservatives, taking into account the type of raw material, the processing temperature, the use of combining additives and in the minimum concentrations actually effective, being aware of the toxic effects of these preservatives to the human health.


Os fungos termorresistentes dos gêneros Byssochlamys, Neosartorya e Talaromyces representam grave problema para a indústria processadora de alimentos, especialmente de frutas e hortaliças, em virtude da ocorrência de ascosporos extremamente resistentes e/ou de micotoxinas termoestáveis. Com o propósito de fornecer subsídios quanto ao uso de quantidades mais racionais de conservantes pela indústria de alimentos e, portanto, tornar seu consumo menos danoso à população, o presente estudo determinou in vitro a concentração mínima de metabissulfito de sódio, benzoato de sódio e sorbato de potássio necessária e sufi ciente para inibir o crescimento micelial e a germinação de ascósporos de B. fulva, N. fischeri e T. flavus em meio de cultivo acidificado (pH 3,5). Foi demonstrado que metabissulfito de sódio em baixas concentrações é tão eficiente na inibição dos fungos mencionados quanto aos demais conservantes em altas concentrações. Por comparação com os procedimentos utilizados pelas indústrias de alimentos, é possível inferir que estas podem reformular o uso de conservantes, considerando-se o tipo de matéria-prima, a temperatura de processamento, a combinação e concentração efetivamente necessária de aditivos, bem como os efeitos tóxicos desses compostos para a saúde humana.

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