Fruit Volatiles to Control Postharvest Rot of Stone Fruits and Pears

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 469a-469
Author(s):  
L.J. Skog ◽  
D.P. Murr ◽  
B.E. Digweed
Keyword(s):  
Volatile Compounds ◽  
Isoamyl Acetate ◽  
Penicillium Expansum ◽  
Effective Control ◽  
In Vitro Tests ◽  
Stone Fruits ◽  
In Situ Tests ◽  
Highly Effective ◽  
Postharvest Rot

Volatile compounds are ubiquitous in plants, giving fruits their characteristic aroma and flavor. There is increasing evidence that these compounds can protect plants from pathogenic organisms. In this trial ≈25 volatile compounds were tested for efficacy against Monilinia fructicola and Penicillium expansum. Both in vitro tests on agar plugs of actively growing pathogens and in situ tests on inoculated stone fruits and pears were conducted. The volatile compounds were grouped into three categories based upon fungicidal activity in vitro: highly effective (fungicidal concentration ≤100 M), moderately effective (fungicidal concentration between 100–200 M) and ineffective (fungicidal concentration >200 M). Highly effective compounds included: acetaldehyde, citral, 2-ethyl-1-hexanol, 2,exadienal, E-2-hexenal, 4-hexen-3-one, linalool, (E,E)2,4-nonadienal, E-2-nonenal, E-3-none-2-one, salicylaldehyde, and valeraldehyde. Moderately effective compounds included: (E,Z) 2,6-nonadienal, propionaldehyde, terpinene, butyl acetate, E-cinnamaldehde, hexanal, E-2-hexen-1-ol, Z-3-hexen-1-ol and isoamyl acetate. Ineffective compounds included: butyrolactone, ethanol, ethyl acetate, and methyl acetate. Effectiveness of the compounds varied with both strain and type of microorganism tested. Concentraions required for effective control were much higher when the compounds were tested on inoculated fruit. Phytotoxicity was a problem with some compounds.

Biocontrol of Sclerotinia wilt of sunflower by Pseudomonas fluorescens and Pseudomonas putida strains

1995 ◽  
Vol 41 (8) ◽  
pp. 685-691 ◽  
Author(s):  
J. M. Expert ◽  
B. Digat
Keyword(s):  
Pseudomonas Putida ◽  
Pseudomonas Fluorescens ◽  
Sclerotinia Sclerotiorum ◽  
Field Experiments ◽  
In Vitro Tests ◽  
Significant Protection ◽  
Bacterial Strains ◽  
In Situ Tests

An increase in early injury to the roots and collar of sunflower plants caused by Sclerotinia sclerotiorum has been observed in France for several years. In vitro tests (inhibition of fungi and cyanide production by bacterial strains) and in situ tests (in nonsterile humus, in a growth chamber) were performed to screen the most efficient Pseudomonas fluorescens and Pseudomonas putida strains effective against this form of injury caused by S. sclerotiorum. Although there was no correlation between in vitro and in situ tests, a positive correlation between in situ tests and field experiments was obtained. At least 1 × 106 bacteria per seed were required for significant protection in in situ tests and field trials demonstrated that significant protection of sunflower was obtained by seed bacterization with selections of P. fluorescens and P. putida.Key words: biological control, Pseudomonas fluorescens, Pseudomonas putida, Sclerotinia sclerotiorum, sunflower, bacterization.

Efficacy of Heat Treatments with Water and Fludioxonil for Postharvest Control of Blue and Gray Molds on Inoculated Pears and Fludioxonil Residues in Fruit

2008 ◽  
Vol 71 (5) ◽  
pp. 967-972 ◽  
Author(s):  
MARIO SCHIRRA ◽  
SALVATORE D'AQUINO ◽  
MAURIZIO MULAS ◽  
RITA ANNA MARIA MELIS ◽  
SARA GIOBBE ◽  
...  
Keyword(s):  
Shelf Life ◽  
Active Ingredient ◽  
Gray Mold ◽  
Heat Treatments ◽  
Hot Water ◽  
Penicillium Expansum ◽  
In Vitro Tests ◽  
Residue Levels ◽  
Accumulation Trend

The residue levels of fludioxonil (FLU) were determined in pear cultivars Precoce di Fiorano, Coscia, and Spadona estiva after a 2-min dip in an aqueous mixture of FLU containing 300 or 100 mg/liter of active ingredient at 20 or 50°C and after 12 days at 17°C and 80% relative humidity (simulated shelf life conditions). The accumulation trend of FLU residues was determined in ‘Precoce di Fiorano’ pears after treatments with 25, 50, 100, or 200 mg/liter of active ingredient at 20 or 50°C for 2 min or at 60°C for 1 min. The efficacy of heat treatments with water and FLU was investigated on artificially inoculated ‘Precoce di Fiorano’, ‘Coscia’, and ‘Spadona estiva’ pears for the control of postharvest blue mold and gray mold caused by Penicillium expansum and Botrytis cinerea, respectively. Treatment with 300 mg/liter FLU at 20°C resulted in residue levels similar to those from treatment with 100 mg/liter FLU at 50°C in ‘Coscia’ fruit but in significantly lower residues in ‘Precoce di Fiorano’ and ‘Spadona estiva’ pears. Post–shelf life residues decreased in all cultivars, especially in ‘Spadona estiva’ pears treated with 300 mg/liter FLU at 20°C. Residue levels of FLU in ‘Precoce di Fiorano’ pears treated at 20, 50, or 60°C were correlated with fungicide dosage. When an equal rate was used, treatment at 50°C resulted in a higher and a notably higher FLU deposition than that found under treatment at 60 and 20°C, respectively. The in vitro tests showed that both pathogens were very sensitive to FLU, with MICs averaging 0.05 and 0.1 mg/liter for B. cinerea and P. expansum isolates, respectively. The 50% effective concentration ranged between 0.01 and 0.05 mg/liter for B. cinerea and between 0.05 and 0.1 mg/liter for P. expansum. In the in vivo trials, hot water treatment effectively reduced the incidence of both diseases during the first 4 to 8 days, depending on cultivar, dip temperature, and type of inoculum. However, as the incubation time proceeded, decay reduction was generally lower and the benefit of heat treatments was notably reduced or almost lost. In contrast, all treatments with FLU had a long-lasting effect. Treatments with heated FLU were more effective than those with unheated FLU; reduced concentrations of active ingredient were required to achieve a comparable control of blue and gray mold decay in these pears.

scholarly journals Peracetic Acid and Chlorine Dioxide for Postharvest Control of Monilinia laxa in Stone Fruits

Plant Disease ◽  
1999 ◽  
Vol 83 (8) ◽  
pp. 773-776 ◽  
Author(s):  
M. Mari ◽  
T. Cembali ◽  
E. Baraldi ◽  
L. Casalini
Keyword(s):  
Chlorine Dioxide ◽  
Peracetic Acid ◽  
Brown Rot ◽  
In Vitro Tests ◽  
Monilinia Laxa ◽  
Stone Fruits ◽  
Duration Of Treatment ◽  
Chemical Product ◽  
Postharvest Control

The effects of different concentrations of peracetic acid (PAA; 62.5, 125, 250, 500, and 1,000 μg/ml)and chlorine dioxide (ClO2; 12.5, 25, 50, 100, and 200 μg/ml) on germination of Monilinia laxa conidia were tested. Conidia germination was related to the concentration of chemical product used, as well as duration of treatment. Complete inhibition of germination was observed with PAA at 500 μg/ml after 5 min of contact with conidia and with ClO2 at 50 μg/ml after 1 min of contact with conidia. The results of in vitro tests were confirmed by inoculation of fruits with treated conidia. The PAA treatment also was effective 1 h after pathogen inoculation but only on plums, for which a 1,000 μg/ml treatment significantly reduced decay incidence by 50%. In a semi-commercial test, pathogen conidia dipped for 20 min in PAA at 250 μg/ml or ClO2 at 10 μg/ml or for 5 min in PAA at 250 μg/ml were completely inhibited, and no brown rot was observed in inoculated wounded nectarines and plums.

Screening of antifungal lactic acid bacteria as bioprotective cultures in yogurts and whey beverage

2021 ◽  
Author(s):  
Rihua Xu ◽  
Ren Sa ◽  
Junwei Jia ◽  
Lanlan Li ◽  
Xiao Wang ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Antifungal Activity ◽  
Lactic Acid Bacteria ◽  
Dairy Products ◽  
Fungal Growth ◽  
Storage Period ◽  
Industrial Applications ◽  
In Vitro Tests ◽  
In Situ Tests

The demand for “preservative-free” food products is rising, and biopreservation seems to be a potential alternative to replace or reduce the use of chemical preservatives. This study’s objective was to assess the antifungal activity of lactic acid bacteria (LAB) (n = 98) and the efficacy and applicability of the chosen bioprotective cultures against fungal spoilers in dairy products. First, 14 strains of antifungal strains were preliminarily screened by in vitro tests against Pichia pastoris D3, Aspergillus niger D1, Geotrichum candidum N1, Kluyveromyces marxianus W1, and Penicillium chrysogenum B1 and validated by challenge tests in yogurts, indicating that the fungal-inhibiting activity of LAB was species specific and yogurts fermented with antifungal LAB cultures were more effective in extending the shelf life. Secondly, the chosen 14 LAB strains were identified by the 16SrDNA sequence analysis and carbohydrate fermentation test. The results were as follows: 9 strains were Lactobacillus plantarum , 3 were Lactobacillus paracasei , 1 was Enterococus faecium , and 1 was Lactobacillus rhamnosus. Among them, active L. plantarum N7 was the chosen and studied factor that affects the antifungal activity using the response surface methodology (RSM). Finally, in situ tests were conducted to validate the activity of L. plantarum N7 in actual dairy products (whey beverage). Physicochemical and microbial indices of whey beverage during storage period exhibited that antifungal L. plantarum N7 could slow the fungal growth and be candidates of interest for industrial applications.

Anti-Diabetic Activity of a Mineraloid Isolate, in vitro and in Genetically Diabetic Mice

2011 ◽  
Vol 81 (1) ◽  
pp. 34-42 ◽  
Author(s):  
Joel Deneau ◽  
Taufeeq Ahmed ◽  
Roger Blotsky ◽  
Krzysztof Bojanowski
Keyword(s):  
Dna Microarrays ◽  
Human Fibroblasts ◽  
Diabetic Animal ◽  
In Vitro Tests ◽  
Diabetic Mice ◽  
Fossil Material ◽  
Expression Of Genes ◽  
Enhanced Expression ◽  
Genetically Diabetic Mice

Type II diabetes is a metabolic disease mediated through multiple molecular pathways. Here, we report anti-diabetic effect of a standardized isolate from a fossil material - a mineraloid leonardite - in in vitro tests and in genetically diabetic mice. The mineraloid isolate stimulated mitochondrial metabolism in human fibroblasts and this stimulation correlated with enhanced expression of genes coding for mitochondrial proteins such as ATP synthases and ribosomal protein precursors, as measured by DNA microarrays. In the diabetic animal model, consumption of the Totala isolate resulted in decreased weight gain, blood glucose, and glycated hemoglobin. To our best knowledge, this is the first description ever of a fossil material having anti-diabetic activity in pre-clinical models.

Comparison of High Purity Factor IX Concentrates and a Prothrombin Complex Concentrate in a Canine Model of Thrombogenicity

1991 ◽  
Vol 66 (05) ◽  
pp. 609-613 ◽  
Author(s):  
I R MacGregor ◽  
J M Ferguson ◽  
L F McLaughlin ◽  
T Burnouf ◽  
C V Prowse
Keyword(s):  
High Purity ◽  
Time Course ◽  
Prothrombin Complex Concentrate ◽  
Degradation Products ◽  
Canine Model ◽  
Factor Ix ◽  
In Vitro Tests ◽  
Albumin Infusion

SummaryA non-stasis canine model of thrombogenicity has been used to evaluate batches of high purity factor IX concentrates from 4 manufacturers and a conventional prothrombin complex concentrate (PCC). Platelets, activated partial thromboplastin time (APTT), fibrinogen, fibrin(ogen) degradation products and fibrinopeptide A (FPA) were monitored before and after infusion of concentrate. Changes in FPA were found to be the most sensitive and reproducible indicator of thrombogenicity after infusion of batches of the PCC at doses of between 60 and 180 IU/kg, with a dose related delayed increase in FPA occurring. Total FPA generated after 100-120 IU/kg of 3 batches of PCC over the 3 h time course was 9-12 times that generated after albumin infusion. In contrast the amounts of FPA generated after 200 IU/kg of the 4 high purity factor IX products were in all cases similar to albumin infusion. It was noted that some batches of high purity concentrates had short NAPTTs indicating that current in vitro tests for potential thrombogenicity may be misleading in predicting the effects of these concentrates in vivo.

A Comparison of the in Vitro and in Vivo Thrombogenic Activity of Factor IX Concentrates Using Stasis (Wessler) and Non-Stasis Rabbit Models

1980 ◽  
Vol 44 (02) ◽  
pp. 081-086 ◽  
Author(s):  
C V Prowse ◽  
A E Williams
Keyword(s):  
Platelet Rich Plasma ◽  
Thrombus Formation ◽  
Factor Ix ◽  
Coagulation System ◽  
In Vitro Tests ◽  
Clinical Use ◽  
Low Activity

SummaryThe thrombogenic effects of selected factor IX concentrates were evaluated in two rabbit models; the Wessler stasis model and a novel non-stasis model. Concentrates active in either the NAPTT or TGt50 in vitro tests of potential thrombogenicity, or both, caused thrombus formation in the Wessler technique and activation of the coagulation system in the non-stasis model. A concentrate with low activity in both in vitro tests did not have thrombogenic effects in vivo, at the chosen dose. Results in the non-stasis model suggested that the thrombogenic effects of factor IX concentrates may occur by at least two mechanisms. A concentrate prepared from platelet-rich plasma and a pyrogenic concentrate were also tested and found to have no thrombogenic effect in vivo.These studies justify the use of the NAPTT and TGt50 in vitro tests for the screening of factor IX concentrates prior to clinical use.

In Vitro Thrombogenicity Tests of Factor IX Concentrates

1979 ◽  
Vol 42 (05) ◽  
pp. 1355-1367 ◽  
Author(s):  
C V Prowse ◽  
A Chirnside ◽  
R A Elton
Keyword(s):  
Factor Viii ◽  
Partial Thromboplastin Time ◽  
Generation Time ◽  
Activated Partial Thromboplastin Time ◽  
Factor Ix ◽  
In Vitro Tests ◽  
Factor Viii Inhibitor ◽  
Factor Ixa ◽  
Viii Inhibitor

SummaryVarious factor IX concentrates have been examined in a number of in vitro tests of thrombogenicity. The results suggest that some tests are superfluous as in concentrates with activity in any of these tests activation is revealed by a combination of the non-activated partial thromboplastin time, the thrombin (or Xa) generation time and factor VIII inhibitor bypassing activity tests. Assay of individual coagulant enzymes revealed that most concentrates contained more factor IXa than Xa. However only a small number of concentrates, chiefly those that had been purposefully activated, contained appreciable amounts of either enzyme.

Inhibition of Fibrinolysis and Fibrinogenolysis in Man: Comparison of ε-Aminocaproic Acid and Kallikrein Inhibitor

1963 ◽  
Vol 10 (01) ◽  
pp. 106-119 ◽  
Author(s):  
E Beck ◽  
R Schmutzler ◽  
F Duckert ◽  
Keyword(s):  
Aminocaproic Acid ◽  
Side Reactions ◽  
In Vitro Tests ◽  
Factor V ◽  
Clinical Use ◽  
Strong Inhibitor ◽  
Kallikrein Inhibitor ◽  
Therapeutic Possibilities

SummaryInhibitor of kallikrein and trypsin (KI) extracted from bovine parotis was compared with ε-aminocaproic acid (EACA): both substances inhibit fibrinolysis induced with streptokinase. EACA is a strong inhibitor of fibrinolysis in concentrations higher than 0, 1 mg per ml plasma. The same amount and higher concentrations are not able to inhibit completely the proteolytic-side reactions of fibrinolysis (fibrinogenolysis, diminution of factor V, rise of fibrin-polymerization-inhibitors). KI inhibits well proteolysis of plasma components in concentrations higher than 2,5 units per ml plasma. Much higher amounts of KI are needed to inhibit fibrinolysis as demonstrated by our in vivo and in vitro tests.Combination of the two substances for clinical use is suggested. Therapeutic possibilities are discussed.

Role of in vivo and in vitro Tests in the Diagnosis of Severe Cutaneous Adverse Reactions (SCAR) to Drug

2019 ◽  
Vol 25 (36) ◽  
pp. 3872-3880 ◽  
Author(s):  
Marcel M. Bergmann ◽  
Jean-Christoph Caubet
Keyword(s):  
Adverse Reactions ◽  
Lymphocyte Transformation ◽  
Stevens Johnson Syndrome ◽  
In Vitro Tests ◽  
High Morbidity ◽  
Patch Tests ◽  
Severe Cutaneous Adverse Reactions ◽  
Cutaneous Adverse Reactions

Severe cutaneous adverse reactions (SCAR) are life-threatening conditions including acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS). Diagnosis of causative underlying drug hypersensitivity (DH) is mandatory due to the high morbidity and mortality upon re-exposure with the incriminated drug. If an underlying DH is suspected, in vivo test, including patch tests (PTs), delayed-reading intradermal tests (IDTs) and in vitro tests can be performed in selected patients for which the suspected culprit drug is mandatory, or in order to find a safe alternative treatment. Positivity of in vivo and in vitro tests in SCAR to drug varies depending on the type of reaction and the incriminated drugs. Due to the severe nature of these reactions, drug provocation test (DPT) is highly contraindicated in patients who experienced SCAR. Thus, sensitivity is based on positive test results in patients with a suggestive clinical history. Patch tests still remain the first-line diagnostic tests in the majority of patients with SCAR, followed, in case of negative results, by delayed-reading IDTs, with the exception of patients with bullous diseases where IDTs are still contra-indicated. In vitro tests have shown promising results in the diagnosis of SCAR to drug. Positivity is particularly high when the lymphocyte transformation test (LTT) is combined with cytokines and cytotoxic markers measurement (cyto-LTT), but this still has to be confirmed with larger studies. Due to the rarity of SCAR, large multi-center collaborative studies are needed to better study the sensitivity and specificity of in vivo and in vitro tests.

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