Antimicrobial Efficacy of Liposome-Encapsulated Citral and Its Effect on the Shelf Life of Shatangju Mandarin

ABSTRACT Liposome-encapsulated citral was prepared by means of a hot homogenization method. The microstructure, particle size, and zeta potential of the capsules were analyzed by transmission electron microscope and dynamic light scattering, respectively, in which the results showed a good dispersion stability of the citral-loaded liposome. In vitro tests showed that liposome-encapsulated citral significantly (P < 0.05) reduced the populations of Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Penicillium italicum more than free citral. In vivo tests conducted on fresh Shatangju mandarin showed that liposome-encapsulated citral-treated fruit exhibited a decay incidence of 56.67%, which is 42.04% lower than free citral-treated fruit (97.78%) after 26 days of storage at 25°C and 60 to 70% relative humidity. Additionally, fruit treated with citral-loaded liposome significantly reduced weight loss and viable yeast and mold during storage. In summary, liposome-encapsulated citral could be an effective antimicrobial agent to extend the shelf life of the Shatangju mandarin. HIGHLIGHTS

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In Vitro Methods as a Tool in Neurotoxicity Studies

Alternatives to Laboratory Animals ◽

10.1177/026119299502300412 ◽

1995 ◽

Vol 23 (4) ◽

pp. 491-496

Author(s):

Hanna Tähti ◽

Leila Vaalavirta ◽

Tarja Toimela

Keyword(s):

Risk Evaluation ◽

Toxicity Testing ◽

In Vitro Models ◽

In Vitro Tests ◽

Industrial Chemicals ◽

Mercury Compounds ◽

Toxicological Data ◽

In Vivo Tests

— There are several hundred industrial chemicals with neurotoxic potential. The neurotoxic risks of most of these chemicals are unknown. Additional methods are needed to assess the risks more effectively and to elucidate the mechanisms of neurotoxicity more accurately than is possible with the conventional methods. This paper deals with general tasks concerning the use of in vitro models in the evaluation of neurotoxic risks. It is based on our previous studies with various in vitro models and on recent literature. The induction of glial fibrillary acidic protein in astrocyte cultures after treatment with known neurotoxicants (mercury compounds and aluminium) is discussed in more detail as an important response which can be detected in vitro. When used appropriately with in vivo tests and with previous toxicological data, in vitro neurotoxicity testing considerably improves risk assessment. The incorporation of in vitro tests into the early stages of risk evaluation can reduce the number of animals used in routine toxicity testing, by identifying chemicals with high neurotoxic potential.

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In vitro and in vivo evaluation of antibacterial activity of Bridelia ferruginea extracts on some clinical isolates

The Journal of Phytopharmacology ◽

10.31254/phyto.2018.7407 ◽

2018 ◽

Vol 7 (4) ◽

pp. 392-398

Author(s):

B.T Yunana ◽

◽

B. B Bukar ◽

J. C Aguiyi ◽

◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Bark Extract ◽

Root Extract ◽

Root Bark ◽

Zone Of Inhibition ◽

Bridelia Ferruginea

The ethanol extracts of root, bark and leaf of Bridelia ferruginea was investigated for antibacterial activity against clinical isolate of Staphylococcus aureus and Escherichia coli. The extracts had significant antibacterial activity in vitro at concentration of 25 mg/ml, 50 mg/ml, 100 mg/ml and 200 mg/ml and in vivo at dose of 50 mg/kg and 100 mg/kg. The root extract in vitro had the highest zone of inhibition, followed by the bark extract for both Staphylococcus aureus and Escherichia coli. The concentration of 200 mg/ml had the highest zone of inhibition in vitro. The minimum inhibitory concentration (MIC) showed a decreasing inhibitory effect of the plant extracts for both Staphylococcus aureus and Escherichia coli as the concentration decreases with root having 3.125 mg/ml, bark having 6.25 mg/ml and leaf having 25 mg/ml for Staphylococcus aureus and Escherichia coli. Likewise, the minimum bactericidal concentration (MBC) showed decreasing bactericide effects with decrease concentration with root having 12.5 mg/ml, bark having 12.5 mg/ml and leaf having 25 mg/ml for Escherichia coli while root had 6.25mg/ml, bark had 12.5mg/ml and leaf had 25mg/ml for Staphylococcus aureus. The in vivo investigation showed that the root and bark extract exhibited antibacterial activity on both Staphylococcus aureus and Escherichia coli at doses of 100mg/kg and 50mg/kg; the root extract had higher activity than the bark and root/bark combined. The dose of 100 mg/kg had the highest colonies reduction for Staphylococcus aureus and Escherichia coli in vivo. Preliminary phytochemical screening of root, bark and leaves of Bridelia ferruginea revealed the presence of tannins, flavonoids, carbohydrates, cardiac glycoside (root, bark and leaves), saponins (root and bark). The presence of tannins, saponins, flavonoid, cardiac glycoside and carbohydrate in the bark and root extracts of the plant indicates that the bark and root extracts were pharmacological importance

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Evaluation du potentiel antimicrobien et de la toxicité des extraits de Jatropha multifida Linn, (Euphorbiaceae)

Journal of Applied Biosciences ◽

10.35759/jabs.151.4 ◽

2020 ◽

Vol 151 ◽

pp. 15550-15558

Author(s):

Amégninou Agban ◽

Yao Hoekou ◽

Passimna Pissang ◽

Tchadjobo Tchacondo ◽

Komlan Batawila

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Candida Albicans ◽

Aqueous Extract ◽

E Coli ◽

Toxicological Studies ◽

Jatropha Multifida

Objectif : L’objectif de ce travail était d’évaluer in vitro l’activité antimicrobienne des extraits de feuilles et tige de Jatropha multifida sur la croissance de Candida albicans, Escherichia coli et Staphylococcus aureus, puis d’évaluer in vivo la toxicité de cette plante. Méthodologie et résultats : Les méthodes de diffusion en milieu gélosé et de microdilution en milieu liquide ont été utilisées pour évaluer l’effet antimicrobien. Une étude en subaigüe était réalisée afin d’explorer les effets toxiques de l’extrait aqueux des feuilles. Les résultats des tests antimicrobiens montrent une activité des extraits de feuilles et tige de J. multifida sur la croissance des souches utilisées avec des diamètres de zones d’inhibition allant de 8 à 25 mm et des concentrations minimales inhibitrices (CMI) variant de 0,039 mg/mL à 1,25 mg/mL à l’exception des souches de E. coli qui sont résistantes aux extraits de la tige. L’administration en subaigüe de l’extrait aqueux des feuilles de J. multifida à la dose de 600 mg/kg entraîne une perte significative de poids chez les souris. Conclusion et applications des résultats : Les extraits aqueux, éthanolique et hydroéthanolique des feuilles et tige de J. multifida possèdent d’activité antimicrobienne et pourraient être utilisés dans le traitement des Candidoses à C. albicans et des infections à S. aureus. Mais l’essai de toxicité subaigüe montre que l’extrait aqueux de la plante serait toxique. Des études toxicologiques approfondies restent donc nécessaires sur ces extraits afin de mieux élucider leur inocuité. Mots-clés : Jatropha multifida, extraits de feuilles et de tige, activités antifongique et antibactérienne, toxicité. Agban et al., J. Appl. Biosci. 2020 Evaluation du potentiel antimicrobien et de la toxicité des extraits de Jatropha multifida Linn, (Euphorbiaceae) 15551 Evaluation of antimicrobial potential and toxicity of Jatropha multifida Linn, (Euphorbiaceae) extracts ABSTRACT Objective: The objective of this study was to evaluate in vitro the antimicrobial activity of leaves and stem of Jatropha multifida extracts against Candida albicans, Escherichia coli and Staphylococcus aureus, and then to evaluate in vivo the toxicity of this plant. Methodology and Results: The agar well-diffusion and the NCCLS broth microdilution methods were used to assess the antimicrobial effect. A subacute study was carried out to explore the toxic effects of the aqueous extract of the leaves. The results of the antimicrobial tests show an activity of the extracts of leaves and stems of J. multifida on the growth of the strains used with diameters of inhibitory zones ranging from 8 to 25 mm and minimum inhibitory concentrations (MIC) varying from 0.039 mg/mL to 1.25 mg/mL exception E. coli strains which are resistant to extracts from the stem. Subacute administration of the aqueous extract of the leaves of J. multifida at a dose of 600 mg/kg leads to a significant loss of weight in the mice. Conclusion and application of findings : The aqueous, ethanolic and hydroethanolic extracts of the leaves and stem of J. multifida have antimicrobial activity and could be used in the treatment of Candidiasis and bacterial infections due respectively to C. albicans and S. aureus. But the subacute toxicity test shows that the aqueous extract of the plant would be toxic. Extensive toxicological studies therefore remain necessary on these extracts in order to better elucidate their safety. Keywords: Jatropha multifida extracts of leaves and stem, antifungal and antibacterial activities, toxicity

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POTENCIAL ANTIBACTERIANO IN VITRO E TOXICOLÓGICO IN VIVO DAS FOLHAS DO JAMBO VERMELHO (Syzygium malaccensis, Myrtaceae) FRENTE A ZEBRAFISH (D. rerio) ADULTO

10.53934/9786599539626.26 ◽

2021 ◽

Author(s):

Fernando E. T. Cunha ◽

Maria I. C. Ferreira ◽

Rafael S. Cruz ◽

Maria J. G. Ferreira ◽

Clarissa M. Aquino ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Listeria Monocytogenes ◽

Danio Rerio ◽

Salmonella Enteritidis

Este trabalho reporta o potencial antibacteriano in vitro e toxicológico in vivo das folhas do jambo (Syzygium malaccense) frente a zebrafish (Danio rerio) adulto (ZFa). As folhas de jambo foram submetidas a desidratação (35 ± 2°C) por 24 horas, trituração e posterior extração de metabólitos por decocção, infusão e maceração com água destilada. Os extratos obtidos foram liofilizados e submetidos a análise de atividade antibacteriana in vitro frente a Gram-negativas (Escherichia coli ATCC 25922, Salmonella Enteritidis IAL 1132) e Gram-positivas (Listeria monocytogenes ATCC 19115 e Staphylococcus aureus ATCC 27664), bem como ao potencial toxicológico in vivo frente ao ZFa. O extrato obtido por infusão se mostrou mais promissor, pois apresentou concentração mínima bactericida (CMB) e concentração mínima inibitória (CMI) com maior potencial frente às gram- positivas (CMB - 6,25 e CMI - 6,25 mg/ml), bem como às gram-negativas (CMB - 25,0 e 3,125 e CMI - 3,125 mg/ml). Todos os extratos testados não se mostraram tóxicos frente ao zebrafish adulto e não alteraram o sistema locomotor dos mesmos. Desta forma, conclui-se que o extrato aquoso das folhas do jambo vermelho (Syzygium malaccense) obtido por infusão é seguro e pode ser utilizado como conservante natural com maior ação antibacteriana. Este trabalho nos conduz a novos estudos de isolamento e caracterização de princípios bioativos.

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Comparison of methods for measurement of the pressure exerted by knitted fabrics

Textile Research Journal ◽

10.1177/0040517516665255 ◽

2016 ◽

Vol 87 (17) ◽

pp. 2117-2126 ◽

Cited By ~ 7

Author(s):

Małgorzata Cieślak ◽

Agnieszka Karaszewska ◽

Ewa Gromadzińska ◽

Izabela Jasińska ◽

Irena Kamińska

Keyword(s):

In Vitro Tests ◽

Knitted Fabric ◽

In Vitro Test ◽

Knitted Fabrics ◽

Weft Knitted Fabric ◽

In Vivo Tests ◽

Vitro Test ◽

Warp Knitted Fabric

The article presents the results of measurements of pressure exerted by two model knitted products – bands with different structure (WI jersey weft-knitted fabric and WII openwork warp-knitted fabric). The tests were carried out with using the I-Scan system (in vivo and in vitro tests) and the STM 579 device (in vitro test). A comparative analysis of the in vivo and in vitro results for the I-Scan method and in vitro results for the I-Scan and STM 579 method was performed. It was found that the pressure values are lower for openwork warp-knitted fabric than for jersey weft-knitted fabric both in the case of the in vitro and in vivo tests, and the values of pressure for the same band are higher in the case of the in vitro tests.

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Staphylococcus aureus Cell Wall Biosynthesis Modulates Bone Invasion and Osteomyelitis Pathogenesis

Frontiers in Microbiology ◽

10.3389/fmicb.2021.723498 ◽

2021 ◽

Vol 12 ◽

Author(s):

Elysia A. Masters ◽

Gowrishankar Muthukrishnan ◽

Lananh Ho ◽

Ann Lindley Gill ◽

Karen L. de Mesy Bentley ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Cell Wall ◽

Surface Protein ◽

Implant Loosening ◽

Penicillin Binding Protein ◽

Cell Wall Synthesis ◽

Transmission Electron ◽

Surface Adhesins

Staphylococcus aureus invasion of the osteocyte lacuno-canalicular network (OLCN) is a novel mechanism of bacterial persistence and immune evasion in chronic osteomyelitis. Previous work highlighted S. aureus cell wall transpeptidase, penicillin binding protein 4 (PBP4), and surface adhesin, S. aureus surface protein C (SasC), as critical factors for bacterial deformation and propagation through nanopores in vitro, representative of the confined canaliculi in vivo. Given these findings, we hypothesized that cell wall synthesis machinery and surface adhesins enable durotaxis- and haptotaxis-guided invasion of the OLCN, respectively. Here, we investigated select S. aureus cell wall synthesis mutants (Δpbp3, Δatl, and ΔmreC) and surface adhesin mutants (ΔclfA and ΔsasC) for nanopore propagation in vitro and osteomyelitis pathogenesis in vivo. In vitro evaluation in the microfluidic silicon membrane-canalicular array (μSiM-CA) showed pbp3, atl, clfA, and sasC deletion reduced nanopore propagation. Using a murine model for implant-associated osteomyelitis, S. aureus cell wall synthesis proteins were found to be key modulators of S. aureus osteomyelitis pathogenesis, while surface adhesins had minimal effects. Specifically, deletion of pbp3 and atl decreased septic implant loosening and S. aureus abscess formation in the medullary cavity, while deletion of surface adhesins showed no significant differences. Further, peri-implant osteolysis, osteoclast activity, and receptor activator of nuclear factor kappa-B ligand (RANKL) production were decreased following pbp3 deletion. Most notably, transmission electron microscopy (TEM) imaging of infected bone showed that pbp3 was the only gene herein associated with decreased submicron invasion of canaliculi in vivo. Together, these results demonstrate that S. aureus cell wall synthesis enzymes are critical for OLCN invasion and osteomyelitis pathogenesis in vivo.

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In Vitro Toxicology: A Challenge for the 21st Century

Alternatives to Laboratory Animals ◽

10.1177/026119299001800104.1 ◽

1990 ◽

Vol 18 (1_part_1) ◽

pp. 19-22

Author(s):

Marcel B. Roberfroid ◽

Fabienne Goethals

Keyword(s):

Animal Models ◽

Animal Experimentation ◽

Experimental Models ◽

Minor Role ◽

In Vitro Tests ◽

Animal Protection ◽

In Vivo Tests ◽

Animal Tests

Foreword — Animal experimentation is an emotional topic, which arouses passionate feelings both in animal protection groups and in the scientific community. For many years, antivivisectionists have fought for the abolition of all animal experimentation, whereas other groups campaign for suppression/reduction of the level of pain animals suffer because of experimentation. Despite all these efforts, the number of animals used in scientific research does not seem to have decreased significantly during the last few years. At best, this number remains constant or shows minor reductions in some countries, whereas in others it is still increasing. In addition to this situation, which certainly does not satisfy the antivivisectionists, the validity of the use of animal models in biomedical research is increasingly being questioned. On the other hand, a number of developments and projects exist which attest to the growing interest of scientists in in vitro models which use few, or even no, animals. Such a change in attitude is particularly evident in practice and research in toxicology, which uses a large number of animals. Taking into account the special status of toxicology among the biomedical sciences, since its practice is required and defined by laws and directives, a semantic problem exists over which adjective should be applied to describe such new methods. For some, it must be alternative — for consistancy to underline the possibility of replacing classical in vivo tests with new in vitro tests, the validity of which is demonstrated by reference to these in vivo tests. For others, it has to be complementary — to characterise the new protocols and the new experimental models which are of interest, because they contribute to the improvement of toxicology by strengthening its scientific nature. For a third group, it must be adjunct — to emphasise the relatively minor role of non-animal tests in relation to the conventional animal tests. It is the second concept that is favoured in this article. The experimental models to which it applies will, according to the Three Rs of Russell & Burch (1), lead either to the replacement of animal models, or to a reduction in the number of animals used or to refinement of test procedures in order to minimise the suffering and stress caused to animals.

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Wound Healing Activity of α-Pinene and α-Phellandrene

Molecules ◽

10.3390/molecules26092488 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2488

Author(s):

Judith Salas-Oropeza ◽

Manuel Jimenez-Estrada ◽

Armando Perez-Torres ◽

Andres Eliu Castell-Rodriguez ◽

Rodolfo Becerril-Millan ◽

...

Keyword(s):

Wound Healing ◽

Healing Process ◽

Folk Medicine ◽

Fibroblast Cell ◽

In Vitro Tests ◽

Low Concentrations ◽

In Vivo Tests ◽

Wound Healing Activity

Bursera morelensis is used in Mexican folk medicine to treat wounds on the skin. Recently, it was shown that the essential oil (EO) of B. morelensis has wound healing activity, accelerating cutaneous wound closure and generating scars with good tensile strength. α-pinene (PIN) and α-phellandrene (FEL) are terpenes that have been found in this EO, and it has been shown in different studies that both have anti-inflammatory activity. The aim of this study was to determine the wound healing activity of these two terpenes. The results of in vitro tests demonstrate that PIN and FEL are not cytotoxic at low concentrations and that they do not stimulate fibroblast cell proliferation. In vivo tests showed that the terpenes produce stress-resistant scars and accelerate wound contraction, due to collagen deposition from the early stages, in wounds treated with both terpenes. Therefore, we conclude that both α-pinene and α-phellandrene promote the healing process; this confirms the healing activity of the EO of B. morelensis, since having these terpenes as part of its chemical composition explains part of its demonstrated activity.

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IMMUNOREACTIONS INVOLVING PLATELETS

Journal of Experimental Medicine ◽

10.1084/jem.107.5.711 ◽

1958 ◽

Vol 107 (5) ◽

pp. 711-729 ◽

Cited By ~ 36

Author(s):

N. Raphael Shulman

Keyword(s):

Plasma Concentration ◽

Complement Fixation ◽

In Vitro Tests ◽

Antibody Activity ◽

Minimal Amount ◽

Thrombocytopenic Purpura ◽

Safe Method ◽

In Vivo Tests

Regulated intravenous doses of quinidine were given to patients with the antibody of quinidine purpura to produce controlled thrombocytopenia without clinical sequelae. The degree of thrombocytopenia and the rate at which it developed were dependent on the relative plasma concentration of quinidine and antibody. By relating in vivo changes in platelet levels to concurrent in vitro tests for antibody activity and to quantitative relationships between reactants determined in Papers I and III of this series, it was concluded that the amount of antibody which attaches to platelets when thrombocytopenia develops is insufficient to cause complement fixation or platelet agglutination. Platelets do not appear to be destroyed directly by reaction with antibody in vivo. The minimal amount of antibody which does attach to platelets in vivo appears to increase their susceptibility to the usual mechanisms of sequestration. Megakaryocytes and blood vessels do not appear to be affected directly by the antibody which causes quinidine purpura, and hemorrhagic manifestations of the disease appear to be consequent to changes in platelets alone. A safe method of performing in vivo tests for the presence of an antibody of drug purpura is described. The implications of the present work in idiopathic thrombocytopenic purpura are discussed.

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Determinación de la cinética, pruebas de crecimiento y efecto de inhibición in vitro de Lactobacillus casei en Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae y Escherichia coli

Revista de la Facultad de Medicina Veterinaria y de Zootecnia ◽

10.15446/rfmvz.v62n2.51992 ◽

2015 ◽

Vol 62 (2) ◽

Author(s):

Henry Jurado-Gámez ◽

Manuel Gúzman-Insuasty

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Streptococcus Agalactiae ◽

Staphylococcus Epidermidis ◽

Lactobacillus Casei ◽

E Coli

Se determinó la cinética, pruebas de crecimiento y el efecto de inhibición in vitro de Lactobacillus casei sobre Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae y Escherichia coli. Se usaron cepas de casa comercial y cepas aisladas en la Vereda La Victoria, Corregimiento de Catambuco al suroccidente del municipio de Pasto, Nariño, Colombia. Se evaluó el efecto de los antibióticos Dicloxacilina, Cefepima, Cefalotina, Ciprofloxacina, Gentamicina, Penicilina, Trimetropim Sulfa y Ampicilina. Se evaluó la inhibición producida por L. casei y su sobrenadante sobre las bacterias patógenas. El crecimiento de la bacteria láctica se evaluó con tres niveles de pH (2,5, 4,5 y 7), tres concentraciones de sales biliares (0,5, 1 y 2%) y dos de bilis bovina (1 y 1,2%), y dos temperaturas (38 y 45°C). Igualmente se determinó la cinética de crecimiento y las variables pH, azúcar total, proteína y ácido láctico. Mediante HPLC se determinaron los péptidos y los ácidos orgánicos presentes en el sobrenadante. L. casei mostró susceptibilidad a la Ciprofloxacina y Ampicilina, mientras que S. aureus mostró susceptibilidad y resistencia a todos los antibióticos para la cepa comercial y aislada respectivamente, el mismo comportamiento se presentó con S. epidermidis. Las cepas de S. agalactiae y E. coli aisladas y comerciales mostraron susceptibilidad a los antibióticos. La cepa láctica mostró un efecto de inhibición de S. aureus, S. epidermidis y S. agalactiae, pero no fue efectiva con E. coli, igual comportamiento se observó con el uso del sobrenadante de la bacteria láctica. Se encontró crecimiento de 1 x 1010 y 5,1 x 107 UFC/ml para 1 y 1,2 % de bilis bovina; 2,3 x 107, 1 x 109 y 3 x 108 UFC/ml para 0,5, 1 y 2 % de sales biliares respectivamente; 1,1 x 1011, 2,0 x 1010 y 1,0 x 1010 UFC/ml para pH de 2,5, 4,5 y 7 respectivamente. La fase exponencial se encontró a 16:48 horas con un crecimiento de 3 x 1010 UFC/ml. La variables pH, azúcar, acidez y proteína durante la fase exponencial fueron de 4,94, 0,88 mg/l, 2,89 mg/l y 1,9 mg/l, respectivamente. La prueba de HPLC para péptidos mostró la presencia de una cadena VAL-TIR-VAL y para ácidos orgánicos se encontró una producción de 83,46% de ácido láctico. L. casei mostró buenas características probiótica que permitirían su aplicación en ensayos in vivo para el control de microorganismos causantes de mastitis subclínica en vacas.

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