scholarly journals Differentiation of Three Homogeneous Groups of Rhizoctonia solani Anastomosis Group 4 by Analysis of Fatty Acids

2001 ◽  
Vol 91 (9) ◽  
pp. 821-830 ◽  
Author(s):  
Janell Stevens Johnk ◽  
Roger K. Jones
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Sugar Beet ◽  
North Dakota ◽  
Rhizoctonia Solani ◽  
Acid Methyl Ester ◽  
Anastomosis Group ◽  
Homogeneous Groups ◽  
Fame Analysis ◽  
Group 4

Profiles of fatty acids from 70 isolates of Rhizoctonia solani anastomosis group (AG)-4 clustered into three groups, corresponding to homogeneous group (HG)-I, HG-II, and a newly described HG-III. Isolates from Georgia peanuts exhibiting limb rot were characterized as gas chromatography (GC) subgroup 1 (GC-1) and contained HG-I isolates. Isolates from diseased soybean hypocotyls grown in North Dakota and sugar beet seedlings, taproots, and tare soil in Minnesota and North Dakota were characterized as GC subgroup 2 (GC-2) and contained predominantly HG-II isolates but also included three distinct isolates based on fatty acid methyl ester (FAME) analysis and morphological features. Selected isolates from North Carolina cucumbers clustered into three distinct groups that corresponded to HG-I, HG-II, and the newly described HG-III. Distinct isolates from the soybean and sugar beet populations clustered with HG-III. Fatty acid profiles of AG-4 were compared with FAME library profiles of AG-1, AG-2 type 2, and AG-3, which were developed in previous studies and were sufficiently different that they could be used to support speciation of this group from R. solani. It is suggested that binomial R. practicola may be appropriate for the portion of AG-4 identified as HG-II.

Sensitivity of Rhizoctonia solani AG 2-2 isolates from soybean and sugar beet to selected SDHI and QoI fungicides

Plant Disease ◽  
2021 ◽  
Author(s):  
Pratibha Sharma ◽  
Dean Malvick ◽  
Ashok Kumar Chanda
Keyword(s):  
Sugar Beet ◽  
North Dakota ◽  
Rhizoctonia Solani ◽  
Fungal Growth ◽  
Anastomosis Group ◽  
Qoi Fungicides ◽  
Quinone Outside Inhibitor ◽  
Periodic Monitoring ◽  
The Mean

Rhizoctonia solani causes root and stem diseases on soybean and sugar beet, and fungicides are commonly used to manage these diseases. Quinone outside inhibitor (QoI) fungicides (pyraclostrobin and azoxystrobin) have been used for in-furrow and post-emergence application since 2000. Succinate dehydrogenase inhibitor (SDHI) fungicides (sedaxane, penthiopyrad, and fluxapyroxad) became popular seed treatments following their registration in Minnesota and North Dakota between 2012 and 2016. Periodic monitoring of sensitivity to these fungicides in R. solani anastomosis group (AG) 2-2 is important to detect potential shifts in sensitivity over time. R. solani AG 2-2 isolates (n=35) collected from soybean and sugar beet in Minnesota and North Dakota were evaluated in vitro for sensitivity. Isolates were considered as baseline or non-baseline for the above mentioned fungicides based on previous potential exposure. The effective concentration (EC50) required to suppress radial fungal growth by 50% was determined. The mean EC50 values for sedaxane, penthiopyrad, fluxapyroxad and pyraclostrobin were 0.1, 0.15, 0.16, and 0.25 µg ml-1, respectively. The mean EC50 value for azoxystrobin for 22 isolates was 0.76 to 1.56 µg ml-1; and EC50 could not be determined for 13 isolates due to < 50% inhibition at the highest concentrations used. The EC50 values for the QoI fungicides did not differ significantly between baseline and non-baseline isolates. EC50 values for SDHI fungicides were significantly higher for isolates collected from soybean than from sugar beet, and isolates collected from both crops had similar EC50 values for pyraclostrobin. All SDHI fungicides and pyraclostrobin effectively suppressed R. solani isolates from soybean and sugar beet at low concentrations in vitro.

scholarly journals Identification and quantification of dicarboxylic fatty acids in head tissue of farmed Nile tilapia (Oreochromis niloticus)

2021 ◽  
Author(s):  
Katja Lehnert ◽  
Mamun M. Rashid ◽  
Benoy Kumar Barman ◽  
Walter Vetter
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Low Income ◽  
Oreochromis Niloticus ◽  
Nile Tilapia ◽  
Daily Intake ◽  
Acid Methyl Ester ◽  
Human Consumption ◽  
The European Union

AbstractNile tilapia (Oreochromis niloticus) was grown in Bangladesh with four different feeding treatments as part of a project that aims to produce fish in a cost-effective way for low-income consumers in developing countries. Fillet and head tissue was analysed because both tissues were destined for human consumption. Gas chromatography with mass spectrometry (GC/MS) analyses of transesterified fatty acid methyl ester extracts indicated the presence of ~ 50 fatty acids. Major fatty acids in fillet and head tissue were palmitic acid and oleic acid. Both linoleic acid and polyunsaturated fatty acids with three or more double bonds were presented in quantities > 10% of total fatty acids in fillet, but lower in head tissue. Erucic acid levels were below the newly proposed tolerable daily intake in the European Union, based on the consumption of 200 g fillet per day. Moreover, further analysis produced evidence for the presence of the dicarboxylic fatty acid azelaic acid (nonanedioic acid, Di9:0) in head tissue. To verify this uncommon finding, countercurrent chromatography was used to isolate Di9:0 and other dicarboxylic acids from a technical standard followed by its quantification. Di9:0 contributed to 0.4–1.3% of the fatty acid profile in head tissue, but was not detected in fillet. Fish fed with increasing quantities of flaxseed indicated that linoleic acid was the likely precursor of Di9:0 in the head tissue samples.

Differentiation between Candida dubliniensis andCandida albicans by Fatty Acid Methyl Ester Analysis Using Gas-Liquid Chromatography

2000 ◽  
Vol 38 (10) ◽  
pp. 3696-3704 ◽  
Author(s):  
Heidrun Peltroche-Llacsahuanga ◽  
Silke Schmidt ◽  
Michael Seibold ◽  
Rudolf Lütticken ◽  
Gerhard Haase
Keyword(s):  
Liquid Chromatography ◽  
Fatty Acid ◽  
Methyl Ester ◽  
Fatty Acid Methyl Ester ◽  
Acid Methyl Ester ◽  
Candida Dubliniensis ◽  
Identification System ◽  
Gas Liquid Chromatography ◽  
Fame Analysis ◽  
Acid Methyl

Candida dubliniensis is often found in mixed culture with C. albicans, but its recognition is hampered as the color of its colonies in primary culture on CHROMagar Candida varies. Furthermore, definite identification of C. dubliniensis is difficult to achieve, time-consuming, and expensive. Therefore, a method to discriminate between these two closely related yeast species by fatty acid methyl ester (FAME) analysis using gas-liquid chromatography (Sherlock Microbial Identification System [MIS]; MIDI, Inc., Newark, Del.) was developed. Although the chromatograms of these two species revealed no obvious differences when applying FAME analysis, a new library (CADLIB) was successfully created using Sherlock Library Generation Software (MIDI). The amount and frequency of FAME was analyzed using library training files (n = 10 for each species), preferentially those comprising reference strains. For testing the performance of the CADLIB, clinical isolates genetically assigned to the respective species (C. albicans, n = 32; C. dubliniensis, n = 28) were chromatographically analyzed. For each isolate tested, MIS computed a similarity index (SI) indicating a hierarchy of possible strain fits. When using the newly created library CADLIB, the SIs for C. albicans andC. dubliniensis ranged from 0.11 to 0.96 and 0.53 to 0.93 (for all but one), respectively. Only three isolates of C. albicans (9.4%) were misidentified as C. dubliniensis, whereas all isolates of C. dubliniensiswere correctly identified. Resulting differentiation accuracy was 90.6% for C. albicans and 100% for C. dubliniensis. Cluster analysis and principal component analysis of the resulting FAME profiles showed two clearly distinguishable clusters matching up with two assigned species for the strains tested. Thus, the created library proved to be well suited to discriminate between these two species.

scholarly journals Fatty Acid Composition and Fat Stability of Raw Milk and Pasteurized Milk from Laoshan Goats

2016 ◽  
Vol 8 (6) ◽  
pp. 149 ◽  
Author(s):  
Cunfang Wang ◽  
Xinman Lou ◽  
Jianmin Wang
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Sedimentation Rate ◽  
Unsaturated Fatty Acids ◽  
Acid Methyl Ester ◽  
Goat Milk ◽  
Raw Milk ◽  
Pasteurized Milk ◽  
Functional Product ◽  
Significant Difference

<p>In this study, the fatty acid profile and fat stability for seven consecutive days of raw milk and pasteurized milk from Laoshan goats have been evaluated by gas chromatography-mass spectrometry (GC-MS) after fatty acid methyl ester. The results showed that the concentrations of short chain fatty acids (SCFA) and saturated fatty acids (SFA) significantly increased by 47.36% and 11.68% after pasteurization respectively, while the concentrations of unsaturated fatty acids (UFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) decreased by 26.08%, 26.45% and 22.15% respectively. The C10:0 (5.39%-8.57%), C12:0 (3.13%-5.28%), C14:0 (8.12%-11.87%), C16:0 (25.59%-28.53%), C18:0 (14.60-13.69%) and C18:1 (33.91-24.92%) are the most predominant fatty acids of Laoshan goat milk with significant differences. Moreover, the fat stabillity for seven consecutive days of raw milk and pasteurized milk was detected by sedimentation rate (R). The fat stability in pasteurized milk was more stable than that in raw milk, the sedimentation rate of raw milk and pasteurized milk consisted in a progressive decrease in the seven days by 82.99% and 79.77% respectively. What’s more, significant difference was observed from 1st day to 4th day between raw milk and pasteurized milk, however, there was no significance from 5th to 7th. This is the first report to fully characterize the fatty acid contents and fat stability of Laoshan goat raw milk and its pasteurized milk and it provided a certain theoretical basis for the research and development of goat milk functional product.</p>

scholarly journals Determination of Whole-Cell Fatty Acid Profiles for the Characterization and Differentiation of Isolates of Rhizoctonia solani AG-4 And AG-7

Plant Disease ◽  
2000 ◽  
Vol 84 (7) ◽  
pp. 785-788 ◽  
Author(s):  
R. E. Baird ◽  
R. D. Gitaitis ◽  
D. E. Carling ◽  
S. M. Baird ◽  
P. J. Alt ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Rhizoctonia Solani ◽  
Euclidean Distance ◽  
Methyl Esters ◽  
Principal Component ◽  
Identification System ◽  
Microbial Identification ◽  
Euclidean Distances

Fatty acid methyl esters (FAMEs) of isolates of Rhizoctonia solani AG-4 and AG-7 were characterized by gas chromatography and analyzed with Microbial Identification System software. Palmitic, stearic, and oleic acids were common in all isolates from both anastomosis groups (AGs) and accounted for 95% of the C14 to C18 fatty acids present. Oleic acid, most common in both R. solani AG-4 and AG-7 isolates, accounted for the greatest percentages of total FAMEs. The presence, quantities, or absence of individual fatty acids could not be used for distinguishing AG-4 and AG-7 isolates. Anteisopentadecanoic and 9-heptadecanoic acids, however, were specific to all three AG-7 isolates from Japan but absent in other AG-7 isolates and all AG-4 isolates. Pentadecanoic acid occurred in only two of the R. solani AG-4 isolates, but was not found in any of the AG-7 isolates. The AG-4 isolates could be distinguished from AG-7 isolates when quantities of FAMEs and key FAME ratios were analyzed with cluster analysis and principle components were plotted. Isolates of AG-7 from Arkansas, Indiana, and Georgia appeared to be more closely related to each other than to AG-7 isolates from Japan and Mexico. These differences in FAMEs were sufficiently distinct that isolate geographical variability could be determined. A dendrogram analysis cluster constructed from the FAMEs data showed results similar to that of the principal component analysis. Euclidean distances of total AG-4 isolates were distinct from total AG-7 isolates. The Arkansas and Indiana AG-7 isolates had a similar Euclidean distance to each another but the percentages were different for the AG-7 isolates from Japan and Mexico. In conclusion, variability of the FAMEs identified in this study would not be suitable as the main diagnostic tool for distinguishing individual isolates of R. solaniAG-4 from AG-7.

Severity, Distribution, and Losses from Taproot Cankers Caused by Rhizoctonia solani in Peanuts1

1988 ◽  
Vol 15 (2) ◽  
pp. 73-75 ◽  
Author(s):  
John T. Turner ◽  
Paul A. Backman
Keyword(s):  
Rhizoctonia Solani ◽  
Surface Area ◽  
Disease Severity ◽  
Negative Correlation ◽  
Root Rot ◽  
High Frequency ◽  
Significant Negative Correlation ◽  
Anastomosis Group ◽  
Group 4

Abstract Research on the ecology of peanut roots from fields in Georgia, Florida, and Alabama revealed a high frequency of sunken, dark cankers on the taproot which persisted to harvest. Isolations from these cankers resulted in recovery of Rhizoctonia solani anastomosis group 4 (AG-4) from more than 50% of the cankers. A survey of peanut fields being harvested during early September revealed that 28% of the fields had an average of more than 50% of the taproot surface area cankered. In contrast, for fields in the same area harvested one month later, 77% had disease severities of less than 25% and none were greater than 50%. In an experiment conducted in 1984, roots from 64 plots were examined and rated for root rot severity and yield. When taproot disease severity was regressed against yield, a highly significant negative correlation (r2 − 0.60, P&lt;0.01) was found.

scholarly journals Characterization and Pathogenicity of Rhizoctonia solani Isolates Affecting Pisum sativum in North Dakota

Plant Disease ◽  
2012 ◽  
Vol 96 (5) ◽  
pp. 666-672 ◽  
Author(s):  
F. M. Mathew ◽  
R. S. Lamppa ◽  
K. Chittem ◽  
Y. W. Chang ◽  
M. Botschner ◽  
...  
Keyword(s):  
Pisum Sativum ◽  
North Dakota ◽  
Rhizoctonia Solani ◽  
Resistance Breeding ◽  
Its Region ◽  
Anastomosis Group ◽  
Field Pea ◽  
State University ◽  
Dry Bean ◽  
North Dakota State University

Acreage of dry field pea (Pisum sativum) in North Dakota has increased approximately eightfold from the late 1990s to the late 2000s to over 200,000 ha annually. A coincidental increase in losses to root rots has also been observed. Root rot in dry field pea is commonly caused by a complex of pathogens which included Fusarium spp. and Rhizoctonia solani. R. solani isolates were obtained from roots sampled at the three- to five-node growth stage from North Dakota pea fields and from symptomatic samples received at the Plant Diagnostic Lab at North Dakota State University in 2008 and 2009. Using Bayesian inference and maximum likelihood analysis of the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA), 17 R. solani pea isolates were determined to belong to anastomosis group (AG)-4 homogenous group (HG)-II and two isolates to AG-5. Pathogenicity of select pea isolates was determined on field pea and two rotation hosts, soybean and dry bean. All isolates caused disease on all hosts; however, the median disease ratings were higher on green pea, dry bean, and soybean cultivars when inoculated with pea isolate AG-4 HG-II. Identification of R. solani AGs and subgroups on field pea and determination of relative pathogenicity on rotational hosts is important for effective resistance breeding and appropriate rotation strategies.

scholarly journals Evaluation of antioxidants on oxidative stability and fatty acid profile of poultry offal oil used in the pet food industry

2021 ◽  
Vol 42 (3Supl1) ◽  
pp. 1813-1824
Author(s):  
Carlos Magno da Rocha Junior ◽  
◽  
Antônio Gilberto Bertechini ◽  
Alexandre de Oliveira Teixeira ◽  
Leonardo Marmo Moreira ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Oxidative Stability ◽  
Fatty Acid Profile ◽  
Food Industry ◽  
Essential Fatty Acids ◽  
Acid Methyl Ester ◽  
Natural Antioxidants ◽  
Compositional Data Analysis ◽  
Pet Food

The aim of this study was to examine the use of antioxidants on the oxidative stability of poultry offal oil used in the pet food industry. Five commercial synthetic and two natural antioxidants were used in the following treatments: Control (CON); CON + (BHT + BHA + ETH95); CON + (BHT + BHA); CON + (BHA + PG + CA); CON + (BHT + BHA + ETH70); CON + BHA; CON + (ASC + rosemary); and CON + (ASC + tocopherols). Inclusion levels were 0.5% for the synthetic and 0.625% for the natural antioxidants. Oxidative stability was determined at three temperatures (90, 110 and 130 ºC). To determine the fatty acid profile, the original sample of the offal oil was considered a negative control. The fatty acids were determined based on the preparation of methyl esters by a transesterification reaction with methanol in alkaline medium, followed by gas chromatography analysis. The different fatty acid types were identified by comparing the retention times of the fatty acid methyl ester standards with the retention times of the observed peaks. Compositional data analysis was carried out. Without the use of antioxidant, induction time is shorter, resulting in lower oxidative stability of the offal oil and consequent loss of its quality due to less time taken to oxidize. The antioxidants used in CON + (BHT + BHA + ETH95), CON + (BHA + PG + CA) and CON + BHA better preserved the essential fatty acids (linolenic and linoleic). Natural antioxidants exhibited higher oxidation, with higher proportions of saturated fatty acids and the worst ω6:ω3 ratios. In conclusion, the synthetic antioxidants used in CON + (BHT + BHA + ETH95), CON + (BHA + PG + CA) and CON + BHA provided greater protection against oxidation and better preserved the essential fatty acids. The natural antioxidants tested in the present study did not provide satisfactory protection.

scholarly journals Participation of Acyl-Coenzyme A Synthetase FadD4 of Pseudomonas aeruginosa PAO1 in Acyclic Terpene/Fatty Acid Assimilation and Virulence by Lipid A Modification

2021 ◽  
Vol 12 ◽  
Author(s):  
Lorena Martínez-Alcantar ◽  
Gabriela Orozco ◽  
Alma Laura Díaz-Pérez ◽  
Javier Villegas ◽  
Homero Reyes-De la Cruz ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Fatty Acid ◽  
Lipid A ◽  
Acid Methyl Ester ◽  
Genetic Redundancy ◽  
Single Mutant ◽  
Fame Analysis ◽  
Metabolic Versatility ◽  
Acyl Coenzyme A

The pathogenic bacterium Pseudomonas aeruginosa possesses high metabolic versatility, with its effectiveness to cause infections likely due to its well-regulated genetic content. P. aeruginosa PAO1 has at least six fadD paralogous genes, which have been implicated in fatty acid (FA) degradation and pathogenicity. In this study, we used mutagenesis and a functional approach in P. aeruginosa PAO1 to determine the roles of the fadD4 gene in acyclic terpene (AT) and FA assimilation and on pathogenicity. The results indicate that fadD4 encodes a terpenoyl-CoA synthetase utilized for AT and FA assimilation. Additionally, mutations in fadD paralogs led to the modification of the quorum-sensing las/rhl systems, as well as the content of virulence factors pyocyanin, biofilm, rhamnolipids, lipopolysaccharides (LPS), and polyhydroxyalkanoates. In a Caenorhabditis elegans in vivo pathogenicity model, culture supernatants from the 24-h-grown fadD4 single mutant increased lethality compared to the PAO1 wild-type (WT) strain; however, the double mutants fadD1/fadD2, fadD1/fadD4, and fadD2/fadD4 and single mutant fadD2 increased worm survival. A correlation analysis indicated an interaction between worm death by the PAO1 strain, the fadD4 mutation, and the virulence factor LPS. Fatty acid methyl ester (FAME) analysis of LPS revealed that a proportion of the LPS and FA on lipid A were modified by the fadD4 mutation, suggesting that FadD4 is also involved in the synthesis/degradation and modification of the lipid A component of LPS. LPS isolated from the fadD4 mutant and double mutants fadD1/fadD4 and fadD2/fadD4 showed a differential behavior to induce an increase in body temperature in rats injected with LPS compared to the WT strain or from the fadD1 and fadD2 mutants. In agreement, LPS isolated from the fadD4 mutant and double mutants fadD1/fadD2 and fadD2/fadD4 increased the induction of IL-8 in rat sera, but IL1-β cytokine levels decreased in the double mutants fadD1/fadD2 and fadD1/fadD4. The results indicate that the fadD genes are implicated in the degree of pathogenicity of P. aeruginosa PAO1 induced by LPS-lipid A, suggesting that FadD4 contributes to the removal of acyl-linked FA from LPS, rendering modification in its immunogenic response associated to Toll-like receptor TLR4. The genetic redundancy of fadD is important for bacterial adaptability and pathogenicity over the host.

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