The allelopathic properties of decomposing buckwheat residues are not directly related to phenolic compounds in soil

Previous studies have shown that residues of common buckwheat roots (BRR) (but not entire common buckwheat plants, BPR) in the soil inhibited the growth of barnyardgrass (Echinochloa crus-galli L.). The objective of the study was to determine how both the residues affect the content of free phenolics, their esters and glycosides in the soil. The aqueous extracts were used to analyse of unbound phenolic compounds, while those bound to the soil were extracted with sodium citrate. Moreover, an in vitro test was used to assess the allelopathic effect of phenolic compounds present in the soil against barnyardgrass. Among the analysed phenolic compounds after 7 days of BPR and BRR decomposition, only ortho-, meta- and para-coumaric acids and apigenin were found in measurable amounts in the soil. The concentrations of free phenolic compounds were very low. Much higher contents occurred for the esters of these compounds, while no glycosides were found. The contents of phenolic compounds bound to soil were many times higher than unbound ones. The 37-day decomposition period resulted in an increase in bound phenolics, while the content of unbound changed slightly. Overall, the levels of phenolic compounds in the soil with the BRR-amended soil and no-buckwheat residue control were low, and significantly higher in the soil with BPR. An in vitro test showed that m-, p-coumaric acids and apigenin added to growth medium at a concentration higher than in the soil did not affect barnyardgrass shoot growth. Since the levels of phenolic compounds in the soil containing BRR and control soil were low and similar, phenolic compounds cannot be directly responsible for the allelopathic properties caused by the presence of BRR.

Download Full-text

Role of the Encapsulation in Bioavailability of Phenolic Compounds

Antioxidants ◽

10.3390/antiox9100923 ◽

2020 ◽

Vol 9 (10) ◽

pp. 923

Author(s):

Josipa Grgić ◽

Gordana Šelo ◽

Mirela Planinić ◽

Marina Tišma ◽

Ana Bucić-Kojić

Keyword(s):

Phenolic Compounds ◽

Targeted Delivery ◽

In Vitro Test ◽

Positive Health ◽

Coating Materials ◽

Vitro Test ◽

Antitumor Properties ◽

Materials Used

Plant-derived phenolic compounds have multiple positive health effects for humans attributed to their antioxidative, anti-inflammatory, and antitumor properties, etc. These effects strongly depend on their bioavailability in the organism. Bioaccessibility, and consequently bioavailability of phenolic compounds significantly depend on the structure and form in which they are introduced into the organism, e.g., through a complex food matrix or as purified isolates. Furthermore, phenolic compounds interact with other macromolecules (proteins, lipids, dietary fibers, polysaccharides) in food or during digestion, which significantly influences their bioaccessibility in the organism, but due to the complexity of the mechanisms through which phenolic compounds act in the organism this area has still not been examined sufficiently. Simulated gastrointestinal digestion is one of the commonly used in vitro test for the assessment of phenolic compounds bioaccessibility. Encapsulation is a method that can positively affect bioaccessibility and bioavailability as it ensures the coating of the active component and its targeted delivery to a specific part of the digestive tract and controlled release. This comprehensive review aims to present the role of encapsulation in bioavailability of phenolic compounds as well as recent advances in coating materials used in encapsulation processes. The review is based on 258 recent literature references.

Download Full-text

An Experimental Investigation of the Natural Frequencies of the Tracheobronchial Network

Volume 1: 20th Biennial Conference on Mechanical Vibration and Noise, Parts A, B, and C ◽

10.1115/detc2005-84376 ◽

2005 ◽

Author(s):

P. M. Au ◽

A. M. Al-Jumaily

Keyword(s):

Experimental Investigation ◽

Dynamic Behavior ◽

Respiratory System ◽

Natural Frequencies ◽

In Vitro Test ◽

Vitro Test ◽

And Control

Determining the natural frequencies of cylindrical non uniform tissues such as the tracheobronchial branched network is a task of multiple difficulties. Two classical experimental procedures, based on mechanical and acoustical excitations, are adopted to determine these frequencies and the results are compared with some numerical values. Although in-vitro test samples of pigs’ tissues are used for the measurements, the results are well indicative of some of the in-vivo dynamic behavior of the respiratory system, which could be correlated to diagnosis and control of lung disorders.

Download Full-text

Chitosan and phenolic compounds in the control of anthracnose in mango

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452021052 ◽

2021 ◽

Vol 43 (6) ◽

Author(s):

Luana Sabrine Silva ◽

Edson Hiydu Mizobutsi ◽

Regina Cássia Ferreira Ribeiro ◽

Fernando da Silva Rocha ◽

Gisele Polete Mizobutsi ◽

...

Keyword(s):

Phenolic Compounds ◽

Mangifera Indica ◽

In Vitro Test ◽

Dunnett Test ◽

Significant Difference ◽

Mango Peel ◽

Total Growth ◽

Vitro Test

Abstract Mango (Mangifera indica L.) has great socioeconomic importance to Brazil, but its production is affected by anthracnose. Chitosan films have shown potential in controlling this disease. In this study, the effect of the association of chitosan with phenolic compounds and extracts on the Colletotrichum tropicaledevelopment was evaluated. Phenolic compounds and extracts from mango peel were incorporated into 2.0% chitosan solutions and tested in vitro. In the in vivo experiment, after pathogen inoculation and application of treatments, fruits were evaluated for anthracnose incidence and severity. Controls consisted of the application of water or pure culture medium and fungicide imazalil. The experimental design was completely randomized and data were submitted to analysis of variance. In the in vitro test and in the assessment of disease intensity, means were compared using the Scott-Knott and Tukey tests (p <0.05), respectively. Controls were compared to the other treatments using the Dunnett test (p <0.05). Total growth inhibition, conidia production and C. tropicale germination were verified with the incorporation of citric, pyrocatecoic and transcinamic acids to chitosan, with no significant difference between them and the fungicide. Low anthracnose incidence and severity was observed in mangoes treated with chitosan combined with phenolic compounds.

Download Full-text

Haemostatic Platelet Plug Formation in the Isolated Rabbit Mesenteric Preparation - An Analysis of Red Blood Cell Participation

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650069 ◽

1980 ◽

Vol 44 (01) ◽

pp. 006-008 ◽

Cited By ~ 12

Author(s):

D Bergqvist ◽

K-E Arfors

Keyword(s):

Whole Blood ◽

Platelet Rich Plasma ◽

Adenosine Diphosphate ◽

In Vitro Test ◽

Pharmacological Agents ◽

Vitro Test ◽

Releasing Effect ◽

Plug Formation

SummaryIn a model using an isolated rabbit mesenteric preparation microvessels were transected and the time until haemostatic plugs formed was registered. Perfusion of platelet rich plasma gave no haemostasis whereas whole blood did. Addition of chlorpromazine or adenosine to the whole blood significantly prolonged the time for haemostasis, and addition of ADP to the platelet rich plasma significantly shortened it. It is concluded that red cells are necessary for a normal haemostasis in this model, probably by a combination of a haemodynamic and ADP releasing effect.The fundamental role of platelets in haemostatic plug formation is unquestionable but there are still problems concerning the stimulus for this process to start. Three platelet aggregating substances have been discussed – thrombin, adenosine diphosphate (ADP) and collagen. Evidence speaking in favour of thrombin is, however, very minimal, and the discussion has to be focused on collagen and ADP. In an in vitro system using polyethylene tubings we have shown that "haemostasis" can be obtained without the presence of collagen but against these results can be argued that it is only another in vitro test for platelet aggregation (1).To be able to induce haemostasis in this model, however, the presence of red blood cells is necessary. To further study this problem we have developed a model where haemostatic plug formation can be studied in the isolated rabbit mesentery and we have briefly reported on this (2).Thus, it is possible to perfuse the vessels with whole blood as well as with platelet rich plasma (PRP) and different pharmacological agents of importance.

Download Full-text

IFN-.GAMMA. Production in Peripheral Lymphocytes from Patients with Drug Eruptions in Response to Stimulation with a Causative Drug. A New in vitro Test for Determining the Causative Drug in Drug Eruptions.

Nishi Nihon Hifuka ◽

10.2336/nishinihonhifu.59.859 ◽

1997 ◽

Vol 59 (6) ◽

pp. 859-863 ◽

Cited By ~ 1

Author(s):

Yukiko NONAKA ◽

Tetsuya KOGA ◽

Shoji TOSHITANI

Keyword(s):

In Vitro Test ◽

Ifn Gamma ◽

Peripheral Lymphocytes ◽

Drug Eruptions ◽

Causative Drug ◽

Vitro Test

Download Full-text

In Vitro Newly Isolated Environmental Phage Activity against Biofilms Preformed by Pseudomonas aeruginosa from Patients with Cystic Fibrosis

Microorganisms ◽

10.3390/microorganisms9030478 ◽

2021 ◽

Vol 9 (3) ◽

pp. 478

Author(s):

Ersilia Vita Fiscarelli ◽

Martina Rossitto ◽

Paola Rosati ◽

Nour Essa ◽

Valentina Crocetta ◽

...

Keyword(s):

Cystic Fibrosis ◽

Pseudomonas Aeruginosa ◽

Multidrug Resistant ◽

In Vitro Test ◽

Chronic Infections ◽

Hospital Environments ◽

Vitro Test ◽

General Reliability ◽

Phage Activity

As disease worsens in patients with cystic fibrosis (CF), Pseudomonas aeruginosa (PA) colonizes the lungs, causing pulmonary failure and mortality. Progressively, PA forms typical biofilms, and antibiotic treatments determine multidrug-resistant (MDR) PA strains. To advance new therapies against MDR PA, research has reappraised bacteriophages (phages), viruses naturally infecting bacteria. Because few in vitro studies have tested phages on CF PA biofilms, general reliability remains unclear. This study aimed to test in vitro newly isolated environmental phage activity against PA isolates from patients with CF at Bambino Gesù Children’s Hospital (OBG), Rome, Italy. After testing in vitro phage activities, we combined phages with amikacin, meropenem, and tobramycin against CF PA pre-formed biofilms. We also investigated new emerging morphotypes and bacterial regrowth. We obtained 22 newly isolated phages from various environments, including OBG. In about 94% of 32 CF PA isolates tested, these phages showed in vitro PA lysis. Despite poor efficacy against chronic CF PA, five selected-lytic-phages (Φ4_ZP1, Φ9_ZP2, Φ14_OBG, Φ17_OBG, and Φ19_OBG) showed wide host activity. The Φ4_ZP1-meropenem and Φ14_OBG-tobramycin combinations significantly reduced CF PA biofilms (p < 0.001). To advance potential combined phage-antibiotic therapy, we envisage further in vitro test combinations with newly isolated phages, including those from hospital environments, against CF PA biofilms from early and chronic infections.

Download Full-text

In Vitro Toxicology Methods in Risk Assessment

Alternatives to Laboratory Animals ◽

10.1177/026119299602400305 ◽

1996 ◽

Vol 24 (3) ◽

pp. 325-331

Author(s):

Iain F. H. Purchase

Keyword(s):

Risk Assessment ◽

Hazard Assessment ◽

Human Health Risk ◽

In Vitro Test ◽

In Vitro Methods ◽

New Concepts ◽

Vitro Test

The title of this paper is challenging, because the question of how in vitro methods and results contribute to human health risk assessment is rarely considered. The process of risk assessment usually begins with hazard assessment, which provides a description of the inherent toxicological properties of the chemical. The next step is to assess the relevance of this to humans, i.e. the human hazard assessment. Finally, information on exposure is examined, and risk can then be assessed. In vitro methods have a limited, but important, role to play in risk assessment. The results can be used for classification and labelling; these are methods of controlling exposure, analogous to risk assessment, but without considering exposure. The Ames Salmonella test is the only in vitro method which is incorporated into regulations and used widely. Data from this test can, at best, lead to classification of a chemical with regard to genotoxicity, but cannot be used for classification and labelling on their own. Several in vitro test systems which assess the topical irritancy and corrosivity of chemicals have been reasonably well validated, and the results from these tests can be used for classification. The future development of in vitro methods is likely to be slow, as it depends on the development of new concepts and ideas. The in vivo methods which currently have reasonably developed in vitro alternatives will be the easiest to replace. The remaining in vivo methods, which provide toxicological information from repeated chronic dosing, with varied endpoints and by mechanisms which are not understood, will be more difficult to replace.

Download Full-text

In vitro dissolution testing models of ocular implants for posterior segment drug delivery

Drug Delivery and Translational Research ◽

10.1007/s13346-021-01043-z ◽

2021 ◽

Author(s):

Muhammad Faris Adrianto ◽

Febri Annuryanti ◽

Clive G. Wilson ◽

Ravi Sheshala ◽

Raghu Raj Singh Thakur

Keyword(s):

Drug Release ◽

Posterior Segment ◽

In Vitro Dissolution ◽

Prolonged Treatment ◽

Term Therapy ◽

In Vitro Test ◽

Dissolution Testing ◽

Vitro Test ◽

Ocular Implants

AbstractThe delivery of drugs to the posterior segment of the eye remains a tremendously difficult task. Prolonged treatment in conventional intravitreal therapy requires injections that are administered frequently due to the rapid clearance of the drug molecules. As an alternative, intraocular implants can offer drug release for long-term therapy. However, one of the several challenges in developing intraocular implants is selecting an appropriate in vitro dissolution testing model. In order to determine the efficacy of ocular implants in drug release, multiple in vitro test models were emerging. While these in vitro models may be used to analyse drug release profiles, the findings may not predict in vivo retinal drug exposure as this is influenced by metabolic and physiological factors. This review considers various types of in vitro test methods used to test drug release of ocular implants. Importantly, it discusses the challenges and factors that must be considered in the development and testing of the implants in an in vitro setup. Graphical abstract

Download Full-text

Animal Models and Alternatives in the Quality Control of Vaccines: Are In Vitro Methods or In Vivo Methods the Scientific Equivalent of the Emperor's New Clothes?

Alternatives to Laboratory Animals ◽

10.1177/026119299502300110 ◽

1995 ◽

Vol 23 (1) ◽

pp. 61-73

Author(s):

Coenraad Hendriksen ◽

Johan van der Gun

Keyword(s):

Quality Control ◽

Test Methods ◽

In Vitro Test ◽

Large Numbers ◽

Alternative Approach ◽

Inactivated Vaccines ◽

Vitro Test

In the quality control of vaccine batches, the potency testing of inactivated vaccines is one of the areas requiring very large numbers of animals, which usually suffer significant distress as a result of the experimental procedures employed. This article deals with the potency testing of diphtheria and tetanus toxoids, two vaccines which are used extensively throughout the world. The relevance of the potency test prescribed by the European Pharmacopoeia monographs is questioned. The validity of the potency test as a model for the human response, the ability of the test to be standardised, and the relevance of the test in relation to the quality of the product are discussed. It is concluded that the potency test has only limited predictive value for the antitoxin responses to be expected in recipients of these toxoids. An alternative approach for estimating the potency of toxoid batches is discussed, in which a distinction is made between estimation of the immunogenic potency of the first few batches obtained from a seed lot and monitoring the consistency of the quality of subsequent batches. The use of animals is limited to the first few batches. Monitoring the consistency of the quality of subsequent batches is based on in vitro test methods. Factors which hamper the introduction and acceptance of the alternative approach are considered. Finally, proposals are made for replacement, reduction and/or refinement (the Three Rs) in the use of animals in the routine potency testing of toxoids.

Download Full-text