Influence of Organic acids (Acetic, Citric acid and Blend) In vitro on growth of E. coli O157: H7: in Poultry feed

Today, the general public has become increasingly aware of salmonellosis problems. Organic acids are known by their antimicrobial potential and commonly used for improving the quality of poultry feed. In this context, the present work evaluated the inhibitory effect of four organic acids, namely, acetic acid, citric acid, lactic acid, and tartaric acid, at different levels of contamination bySalmonella typhimurium. The neutralization of these organic acidsin vitroand in the presence of one-day-old chick’s organs was also investigated during the search forSalmonellaserovars in birds as described in the Moroccan standard “NM 08.0.550.” The effect of four organic acids onSalmonella typhimuriumwas testedin vitroand in the presence of chick’s organs at different concentrations set of strain and organic acids tested. The MIC results demonstrated that tartaric acid, citric acid, and acetic acid inhibitedSalmonella typhimuriumat concentrations of 0.312%, 0.625%, and 0.512% for the three levels of strain: 10, 100, and 103 CFU/ml, respectively, while lactic acid and depending on the amount of the strain introduced acts differently: 0.078% for 10 CFU/ml and 0.156% for 100 and 103 CFU/ml. The concentration of 0.04M of Na2HPO4solution has proved,in vitro, in caecums and organs of chicks (in presence of organic acids) that strain introduced, even at low concentrations, can be recovered. The use of additives has beneficial effects inSalmonellacontrol program. However, the present results recommend the amendment ofSalmonellaresearch standard, taking into account the probable presence of organic acids in digestive content of one-day-old chicks.

Download Full-text

Survival of Escherichia coliO157:H7 in Synthetic Gastric Fluid after Cold and Acid Habituation in Apple Juice or Trypticase Soy Broth Acidified with Hydrochloric Acid or Organic Acids

Journal of Food Protection ◽

10.4315/0362-028x-61.8.939 ◽

1998 ◽

Vol 61 (8) ◽

pp. 939-947 ◽

Cited By ~ 62

Author(s):

HEIDI E. ULJAS ◽

STEVEN C. INGHAM

Keyword(s):

Lactic Acid ◽

Citric Acid ◽

Organic Acids ◽

Apple Juice ◽

Acid Tolerance ◽

Storage Conditions ◽

Gastric Fluid ◽

E Coli ◽

Storage Media ◽

Strain Storage

Extreme acid tolerance of Escherichia coli O157:H7 has raised doubts about the safety of acidic foods. This study examined whether prior storage in acidic and/or cold conditions enhanced survival of E. coli O157 :H7 in synthetic gastric fluid (SGF). Three E. coli O157:H7 strains were stored in trypticase soy broth (TSB; acidified with HCl, malic acid, citric acid, or lactic acid) or pH 3.5 and 6.5 (nonacidic control) apple juice at 4 and 21°C for ≤7 days and then were incubated in pH 2.5 SGF at 37°C for 4 h. Cells survived better in apple juice than in TSB containing organic acids, suggesting that juice constituents other than organic acids protect E. coli O157:H7. Refrigeration combined with low pH best protected cells in apple juice and acidified TSB, but, compared to the nonacidic control, only acidified TSB enhanced subsequent survival in pH 2.5 SGF. Equal survival in SGF occurred after storage in pH 3.5 or 6.5 apple juice at 4°C, suggesting that low temperature alone in apple juice enhanced acid tolerance. Two strains stored at 4°C in TSB containing malic or citric acid subsequently survived better in SGF than cells stored in nonacidified TSB but poorer than cells stored in the presence of HCl. These differences reflect the higher pKa of these organic acids. However, subsequent survival of these strains in SGF was poorer after refrigerated storage in apple juice than in TSB containing citric or malic acids. Cells stored in lactic acid were most likely to be completely eliminated upon transfer to SGF. Differences in survival in storage media or SGF related to strain, storage conditions, or acidifier were consistent and often statistically significant (P < 0.05). Although the survival of E. coli O157:H7 in refrigerated acidic beverages may not be affected by the type of acidifier used, the subsequent survival in SGF of this pathogen may be critically dependent on this factor.

Download Full-text

BX795-Organic Acid Coevaporates: Evaluation of Solid-State Characteristics, In Vitro Cytocompatibility and In Vitro Activity against HSV-1 and HSV-2

Pharmaceutics ◽

10.3390/pharmaceutics13111920 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1920

Author(s):

Yogesh Sutar ◽

Tejabhiram Yadavalli ◽

Sagar Kumar Paul ◽

Sudipta Mallick ◽

Raghuram Koganti ◽

...

Keyword(s):

Citric Acid ◽

Antiviral Activity ◽

Organic Acids ◽

Organic Acid ◽

Tartaric Acid ◽

Fumaric Acid ◽

Amorphous Systems ◽

Amorphous System ◽

Hsv 1

BX795 is a TANK binding kinase-1 inhibitor that has shown excellent therapeutic activity in murine models of genital and ocular herpes infections on topical delivery. Currently, only the BX795 free base and its hydrochloride salt are available commercially. Here, we evaluate the ability of various organic acids suitable for vaginal and/or ocular delivery to form BX795 salts/cocrystals/co-amorphous systems with the aim of facilitating pharmaceutical development of BX795. We characterized BX795-organic acid coevaporates using powder X-ray diffractometry, Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, 1H-nuclear magnetic resonance spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) to elucidate the interaction between BX795 and various organic acids such as taurine, maleic acid, fumaric acid, tartaric acid, and citric acid. Furthermore, using human corneal epithelial cells and HeLa cells, we evaluated BX795-organic acid coevaporates for in vitro cytocompatibility and in vitro antiviral activity against herpes simplex virus-type 1 (HSV-1) and type-2 (HSV-2). Our studies indicate that BX795 forms co-amorphous systems with tartaric acid and citric acid. Interestingly, the association of organic acids with BX795 improved its thermal stability. Our in vitro cytocompatibility and in vitro antiviral studies to screen suitable BX795-organic acid coevaporates for further development show that all BX795-organic acid systems, at a concentration equivalent to 10 µM BX795, retained antiviral activity against HSV-1 and HSV-2 but showed differential cytocompatibility. Further, dose-dependent in vitro cytocompatibility and antiviral activity studies on the BX795-fumaric acid system, BX795-tartaric acid co-amorphous system, and BX795-citric acid co-amorphous system show similar antiviral activity against HSV-1 and HSV-2 compared to BX795, whereas only the BX795-citric acid co-amorphous system showed higher in vitro cytocompatibility compared to BX795.

Download Full-text

Behavior of Acid-Adapted and Unadapted Escherichia coli O157:H7 When Exposed to Reduced pH Achieved with Various Organic Acids

Journal of Food Protection ◽

10.4315/0362-028x-62.5.451 ◽

1999 ◽

Vol 62 (5) ◽

pp. 451-455 ◽

Cited By ~ 57

Author(s):

JEE-HOON RYU ◽

YUN DENG ◽

LARRY R. BEUCHAT

Keyword(s):

Escherichia Coli ◽

Acetic Acid ◽

Lactic Acid ◽

Citric Acid ◽

Organic Acids ◽

Malic Acid ◽

Escherichia Coli O157 ◽

E Coli ◽

Ph Values ◽

Acid Ph

A study was done to determine if various organic acids differ in their inhibitory or lethal activity against acid-adapted and unadapted Escherichia coli O157:H7 cells. E. coli O157:H7 strain E0139, isolated from venison jerky, was grown in tryptic soy broth (TSB) and in TSB supplemented with 1% glucose (TSBG) for 18 h at 37°C, then plated on tryptic soy agar (TSA) acidified with malic, citric, lactic, or acetic acid at pH 5.4, 5.1, 4.8, 4.5, 4.2, and 3.9. Regardless of whether cells were grown in TSB or TSBG, visible colonies were not formed when plated on TSA acidified with acetic, lactic, malic, or citric acids at pH values of ≤5.4, ≤4.5, ≤4.2, or ≤4.2, respectively. Cells not adapted to reduced pH did not form colonies on TSA acidified with lactic acid (pH 3.9) or acetic acid (pH 3.9 and 4.2); however, a portion of acid-adapted cells remained viable on TSA containing lactic acid (pH 3.9) or acetic acid (pH 4.2) and could be recovered in TSB. Inactivation of acid-adapted cells was less than that of unadapted cells in TSB acidified at pH 3.9 with citric, lactic, or acetic acid and at pH 3.4 with malic acid. Significantly (P ≤ 0.05) higher numbers of acid-adapted cells, compared with unadapted cells, were detected 12 h after inoculation of TSB acidified with acetic acid at pH 3.9; in TSB containing lactic acid (pH 3.9), the number of acid-adapted cells was higher than the number of unadapted cells after 5 h. In TSB acidified at pH 3.9 with citric acid or pH 3.4 with malic acid, significantly higher numbers of acid-adapted cells survived. This study shows that organic acids differ in their inhibitory or lethal activity against acid-adapted and unadapted E. coli O157:H7 cells, and acid-adapted cells are more tolerant than unadapted cells when subsequently exposed to reduced pH caused by these acids.

Download Full-text

Antimicrobial activity of a selection of organic acids, their salts and essential oils against swine enteropathogenic bacteria

Porcine Health Management ◽

10.1186/s40813-019-0139-4 ◽

2019 ◽

Vol 5 (1) ◽

Cited By ~ 10

Author(s):

Manuel Gómez-García ◽

Cinta Sol ◽

Pedro J. G. de Nova ◽

Mónica Puyalto ◽

Luis Mesas ◽

...

Keyword(s):

Antimicrobial Activity ◽

Organic Acids ◽

Formic Acid ◽

Essential Oils ◽

Bacterial Species ◽

Additive Effect ◽

Similar Activity ◽

E Coli ◽

Selection Of

Abstract Background Accurate screening of new alternative antimicrobial compounds is essential for their use to control pathogens in swine production due to the replacement of antibiotics and zinc oxide. Most in vitro studies have separately reported the antimicrobial activity of organic acids and essential oils (EOs) using diverse methods for susceptibility testing. In addition, in vitro outcomes can help in the selection of the suitable antimicrobial compound and effective combinations of these compounds in the control of pathogens of interest in pork production. Therefore, the aim of this study is to determinate the antibacterial activity of six organic acids and six EOs against Escherichia coli, Salmonella spp. and Clostridium perfringens isolates, some of them multi-resistant to antibiotics, from swine origin. The synergistic effects between the products with higher activity for each bacteria were also calculated. Results All products tested showed activity against at least one bacterial species, except for black pepper EO. The results showed that formic acid with the shortest chain length was the most effective against E. coli and Salmonella spp., while the sodium salt of coconut fatty acid distillates with long chain acids was the most effective against C. perfringens. The susceptibility of isolates tested to EOs was similar, a result that demonstrates a similar activity of these products against phylogenetically unrelated pathogens. In addition, an additive effect was shown for carvacrol-oregano EO for E. coli, formic acid-carvacrol and formic acid-thymol for Salmonella spp. and carvacrol-cinamaldehyde for C. perfringens. Conclusions The susceptibility of isolates to EOs was similar, a result that demonstrates a similar activity of these products against phylogenetically unrelated pathogens in contrast to organic acids. In addition, an additive effect was shown for several combinations of these compounds.

Download Full-text

Growth of Campylobacter in Media Supplemented with Organic Acids†

Journal of Food Protection ◽

10.4315/0362-028x-69.1.34 ◽

2006 ◽

Vol 69 (1) ◽

pp. 34-38 ◽

Cited By ~ 11

Author(s):

ARTHUR HINTON

Keyword(s):

Lactic Acid ◽

Citric Acid ◽

Organic Acids ◽

Succinic Acid ◽

Malic Acid ◽

In Vitro Growth ◽

Acid Growth ◽

Basal Media ◽

Campylobacter Spp

The growth of Campylobacter spp. in media supplemented with organic acids was examined. A Bioscreen C Microbiology Reader was used to measure growth of cultures incubated at 37°C for 48 h in a tryptose–yeast extract basal broth medium and in basal broth supplemented with 10, 20, 30, 40, or 50 mM citric, fumaric, lactic, malic, or succinic acid. Growth of three of six isolates was significantly greater (P ≤ 0.05) in media supplemented with 20 to 50 mM citric acid than in nonsupplemented media, growth of five of six isolates was significantly greater in media supplemented with 10 to 50 mM succinic acid than in nonsupplemented media, and growth of six of six isolates was significantly greater in media supplemented with 10 to 50 mM fumaric or malic acid or with 20 to 50 mM lactic acid than in nonsupplemented media. Isolates were also cultured in basal media supplemented with a mixture of 10, 20, 30, 40, or 50 mM fumaric, malic, lactic, and succinic acids. Results indicated that the growth of all Campylobacter isolates was significantly greater in media supplemented with mixtures containing each of these organic acids at 10 to 40 mM than in nonsupplemented media. These findings indicate that in vitro growth of Campylobacter spp. may be significantly enhanced in media supplemented with organic acids that support the growth of these bacteria.

Download Full-text

Nature-Identical Compounds and Organic Acids Reduce E. coli K88 Growth and Virulence Gene Expression In Vitro

Toxins ◽

10.3390/toxins12080468 ◽

2020 ◽

Vol 12 (8) ◽

pp. 468

Author(s):

Andrea Bonetti ◽

Benedetta Tugnoli ◽

Barbara Rossi ◽

Giulia Giovagnoni ◽

Andrea Piva ◽

...

Keyword(s):

Organic Acids ◽

Virulence Genes ◽

Virulence Gene ◽

Pcr Analysis ◽

Virulence Gene Expression ◽

E Coli ◽

Heat Stable ◽

Bacterial Genes ◽

Lethal Doses

Post-weaning diarrhoea (PWD) is one of the long-standing challenges in pig husbandry. Due to the risks of resistance caused by antibiotics (AB) misuse, conventional treatments against Escherichia coli K88 (E. coli K88), the PWD etiological agent, urgently need to be replaced. Organic acids (OA) and nature-identical compounds (NIC) are currently finding a central role in infection management thanks to their recognized antimicrobial activity. This study investigated the susceptibility of an E. coli K88 field strain to a wide panel of AB, NIC, and OA. Secondly, we evaluated the ability of sub-lethal doses of the most active compounds to modulate the expression of E. coli K88 virulence genes. Results showed that the bacterial strain was resistant to many of the tested antibiotics, but an antimicrobial action was registered for selected NIC and OA. The quantitative PCR analysis revealed that thymol, carvacrol, eugenol, and benzoic acid were able to downregulate (p < 0.05) the expression of bacterial genes related to motility, adhesion to enterocytes, heat-labile (LT) and heat-stable (ST) toxin secretion, quorum sensing, and biofilm formation. Therefore, this study demonstrated that selected OA and NIC not only control E. coli K88 growth but also modulate the expression of many virulence genes at sub-lethal doses, thus offering new insights on their mechanism of action and suggesting a powerful tool to manage PWD.

Download Full-text

Organic Acids as Sanitizers for Natamycin and other Fungicides in Postharvest Recirculating Application Systems for Citrus

Plant Disease ◽

10.1094/pdis-01-21-0227-re ◽

2021 ◽

Author(s):

Daniel Chen ◽

Helga Forster ◽

Kevin Nguyen ◽

James Adaskaveg

Keyword(s):

Citric Acid ◽

The United States ◽

Coli Strain ◽

Laboratory Studies ◽

Human Pathogens ◽

E Coli ◽

Application Systems ◽

Green Mold ◽

Pathogenic Escherichia Coli

Natamycin is a new postharvest biofungicide for citrus and some other fruit crops in the United States that can be effectively used in recycling drench or flooder treatments. These types of applications necessitate sanitation of the fungicide solution to ensure that it remains free from contamination by bacteria that potentially are human pathogens. In in vitro experiments, heated (48°C) citric acid (1,100 μg/ml or 2,200 μg/ml) amended with sodium dodecylbenzensulfonate (SDBS; 55 μg/ml or 110 μg/ml, respectively) significantly reduced viability of E. coli in natamycin solutions by >5 log10 as compared to the control. In laboratory studies with Penicillium digitatum-inoculated lemon fruit, 1,000 μg/ml natamycin mixed with lactic or citric acids (1,000 μg/ml each) and with or without SDBS (55 μg/ml) was effective in significantly reducing green mold. Natamycin mixed with lactic acid at 2000 μg/ml or higher, however, caused fruit injury resulting in browning and pitting of the rind. Natamycin was incompatible with peroxyacetic acid resulting in reduced efficacy of the fungicide against green mold, whereas sodium hypochlorite lost its toxicity to a non-pathogenic Escherichia coli strain although the performance of natamycin was not affected. In heated (average 49°C) drench treatments on an experimental packingline, natamycin (1,000 μg/ml), fludioxonil (300 μg/ml), or azoxystrobin (300 μg/ml) mixed with citric acid (1,000 μg/ml)-SDBS (55 μg/ml) were effective against green1 mold without fruit injury. At a pH between 3.6 and 3.8, citric acid-SDBS significantly reduced the viability of E. coli by approximately 4 log10 in mixtures with fludioxonil or azoxystrobin, but not with natamycin. Natamycin (1,000 μg/ml) mixed with 2000 μg/ml citric acid and SDBS (4 μg/ml), however, significantly reduced E. coli counts by >4 log10 within 4 min when the pH was maintained between 3.0 and 3.3, and efficacy of the fungicide was retained. The use of citric acid with a surfactant can be a viable alternative sanitation method for natamycin in citrus packinghouses utilizing heated recirculating fungicide systems.

Download Full-text

Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

10.26434/chemrxiv.7725002.v1 ◽

2019 ◽

Author(s):

Priya Prakash ◽

Travis Lantz ◽

Krupal P. Jethava ◽

Gaurav Chopra

Keyword(s):

Amyloid Beta ◽

Western Blots ◽

Force Microscopy ◽

E Coli ◽

Atomic Force ◽

Set Up ◽

Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

Download Full-text

Антимикробная активность лиофилизированного водного извлечения Caragana jubata (Pall.) Poir.

Химико-фармацевтический журнал ◽

10.30906/0023-1134-2020-54-3-42-44 ◽

2020 ◽

Vol 54 (3) ◽

pp. 42-44

Author(s):

Павел Алексеевич Какорин ◽

Татьяна Владимировна Фатеева ◽

Ольга Ивановна Терешкина ◽

Ирина Борисовна Перова ◽

Галина Владиславовна Раменская ◽

...

Keyword(s):

E Coli

На основании ранее проведенных исследований установлен профиль флавоноидов лиофилизированного водного извлечения, полученного из побегов C. jubata. В связи с тем, что, согласно данным литературы, флавоноиды являются потенциальными ингибиторами микроорганизмов, проведено изучение антимикробной активности лиофилизата в опытах in vitro с использованием скринигового метода определения антимикробной активности для препаратов растительного происхождения. При изучении бактериостатической и фунгистатической активности в опытах in vitro использовали метод двукратного серийного разведения препаратов в жидких питательных средах. В результате исследования лиофилизированного водного извлечения караганы гривастой установлено наличие умеренной антимикробной активности в отношении всех изученных штаммов патогенных микроорганизмов: грамположительных и грамотрицательных бактерий (S. aureus, E. coli, P. vulgaris, P. aeruginosa), дрожжеподобных и мицелиальных грибов (C. albicans, M. canis). Полученные данные позволяют рекомендовать лиофилизированное водное извлечение караганы гривастой для создания на его основе лекарственных форм наружного применения для лечения заболеваний кожи и слизистых оболочек, связанных с бактериальным воспалительным процессом.

Download Full-text