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1.
J Chromatogr A ; 1651: 462297, 2021 Aug 16.
Article in English | MEDLINE | ID: mdl-34111676

ABSTRACT

While current trends in Green Analytical Chemistry aim at reducing or simplifying sample treatment, food usually comprises complex matrices where direct analysis is not possible in most cases. In this context, sample treatment plays a pivotal role. Biogenic amines are naturally formed in many foodstuffs due to the action of microorganisms, while their presence has been associated with adverse health effects. In this work, the extraction of seven biogenic amines (cadaverine, histamine, phenylethylamine, putrescine, spermidine, spermine, and tyramine) from beer samples has been simplified using laboratory filter paper as sorbent without any further modification. The analysis of the eluates by direct infusion mass spectrometry reduces the time of analysis, increasing the sample throughput. This simple but effective method enabled the determination of the analytes with limits of detection as low as 0.06 mg L-1 and relative standard deviations better than 11.9%. The suitability of the method has been assessed by analyzing eight different types of beers by the standard addition method.


Subject(s)
Beer/analysis , Biogenic Amines/isolation & purification , Cellulose/chemistry , Filtration , Adsorption , Biogenic Amines/chemistry , Calibration , Hydrogen-Ion Concentration , Osmolar Concentration , Paper , Reference Standards , Tandem Mass Spectrometry/methods
2.
Anal Methods ; 12(24): 3074-3091, 2020 06 26.
Article in English | MEDLINE | ID: mdl-32930167

ABSTRACT

The simplification of the analytical procedures, including cost-effective materials and detectors, is a current research trend. In this context, paper has been identified as a useful material thanks to its low price and high availability in different compositions (office, filter, chromatographic). Its porosity, flexibility, and planar geometry permit the design of flow-through devices compatible with most instrumental techniques. This article provides a general overview of the potential of paper, as substrate, on the simplification of analytical chemistry methodologies. The design of paper-based sorptive phases is considered in-depth, and the different functionalization strategies are described. Considering our experience in sample preparation, special attention has been paid to the use of these phases under the classical microextraction-analysis workflow, which usually includes a chromatographic separation of the analytes before their determination. However, the interest of these materials extends beyond this field as they can be easily implemented into spectroscopic and electrochemical sensors. Finally, the direct analysis of paper substrates in mass spectrometry, in the so-called paper-spray technique is also discussed. This review is more focused on presenting ideas rather than the description of specific applications to draw a general picture of the potential of these materials.

3.
Anal Bioanal Chem ; 412(15): 3547-3557, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32246179

ABSTRACT

Paper-based analytical devices (PADs) have encountered a wealth of applications in recent years thanks to the numerous advantages of paper as a support. A silver nanoflower (AgNF) modified paper-based dual substrate for both surface-enhanced Raman spectroscopy (SERS) and ambient pressure paper spray mass spectrometry (PS-MS) was developed. AgNFs were immobilized on nylon-coated paper modified with silver and ethylenediamine. The developed substrate was characterized via scanning electron microscopy and infrared spectroscopy. The densely packed nanoscale petals of the AgNFs lead to a large number of so-called hot spots at their overlapping points, which result in an enhancement of the Raman signal. In addition, the presence of the AgNFs produces an increase in the sensitivity of the mass spectrometric analysis as compared with bare paper and nylon/Ag-coated paper. The dual substrate was evaluated for the identification and quantification of ketoprofen in aqueous standards as well as human saliva from healthy volunteers. The method enables the determination of ketoprofen with a limit of detection and limit of quantification via PS-MS of 0.023 and 0.076 mg L-1, respectively, with a relative standard deviation (RSD) of 3.4% at a concentration of 0.1 mg L-1. This dual substrate enables the simple and fast detection of ketoprofen with minimal sample preparation, providing complementary Raman and mass spectrometric information. Graphical abstract.

6.
Tech Coloproctol ; 21(10): 795-802, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28755255

ABSTRACT

BACKGROUND: The aim of the present study was to evaluate the diagnostic accuracy of magnetic resonance (MR) defecography and compare it with videodefecography in the evaluation of obstructed defecation syndrome. METHODS: This was a prospective cohort test accuracy study conducted at one major tertiary referral center on patients with a diagnosis of obstructed defecation syndrome who were referred to the colorectal surgery clinic in a consecutive series from 2009 to 2012. All patients underwent a clinical examination, videodefecography, and MR defecography in the supine position. We analyzed diagnostic accuracy for MR defecography and performed an agreement analysis using Cohen's kappa index (κ) for each diagnostic imaging examination performed with videodefecography and MR defecography. RESULTS: We included 40 patients with Rome III diagnostic criteria of obstructed defecation syndrome. The degree of agreement between the two tests was as follows: almost perfect for anismus (κ = 0.88) and rectal prolapse (κ = 0.83), substantial for enterocele (κ = 0.80) and rectocele grade III (κ = 0.65), moderate for intussusception (κ = 0.50) and rectocele grade II (κ = 0.49), and slight for rectocele grade I (κ = 0.30) and excessive perineal descent (κ = 0.22). Eighteen cystoceles and 11 colpoceles were diagnosed only by MR defecography. Most patients (54%) stated that videodefecography was the more uncomfortable test. CONCLUSIONS: MR defecography could become the imaging test of choice for evaluating obstructed defecation syndrome.


Subject(s)
Constipation/diagnostic imaging , Defecography/methods , Magnetic Resonance Imaging , Video Recording , Adult , Aged , Female , Humans , Intussusception/diagnostic imaging , Male , Middle Aged , Prospective Studies , Rectal Prolapse/diagnostic imaging , Rectocele/diagnostic imaging , Supine Position , Syndrome
7.
Br J Cancer ; 116(10): 1294-1301, 2017 May 09.
Article in English | MEDLINE | ID: mdl-28359078

ABSTRACT

BACKGROUND: Investigating tumour evolution and acquired chemotherapy resistance requires analysis of sequential tumour material. We describe the feasibility of obtaining research biopsies in women with relapsed ovarian high-grade serous carcinoma (HGSC). METHODS: Women with relapsed ovarian HGSC underwent either image-guided biopsy or intra-operative biopsy during secondary debulking, and samples were fixed in methanol-based fixative. Tagged-amplicon sequencing was performed on biopsy DNA. RESULTS: We screened 519 patients in order to enrol 220. Two hundred and two patients underwent successful biopsy, 118 of which were image-guided. There were 22 study-related adverse events (AE) in the image-guided biopsies, all grades 1 and 2; pain was the commonest AE. There were pre-specified significant AE in 3/118 biopsies (2.5%). 87% biopsies were fit-for-purpose for genomic analyses. Median DNA yield was 2.87 µg, and was higher in biopsies utilising 14 G or 16 G needles compared to 18 G. TP53 mutations were identified in 94.4% patients. CONCLUSIONS: Obtaining tumour biopsies for research in relapsed HGSC is safe and feasible. Adverse events are rare. The large majority of biopsies yield sufficient DNA for genomic analyses-we recommend use of larger gauge needles and methanol fixation for such biopsies, as DNA yields are higher but with no increase in AEs.


Subject(s)
Carcinoma/genetics , Carcinoma/secondary , DNA, Neoplasm/analysis , Image-Guided Biopsy , Liver Neoplasms/pathology , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Peritoneal Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Class I Phosphatidylinositol 3-Kinases , DNA Mutational Analysis , DNA, Neoplasm/isolation & purification , ErbB Receptors/genetics , Feasibility Studies , Female , Humans , Image-Guided Biopsy/adverse effects , Image-Guided Biopsy/instrumentation , Liver/pathology , Liver Neoplasms/secondary , Lymph Nodes/pathology , Lymphatic Metastasis , Middle Aged , Neoplasm Grading , Omentum/pathology , PTEN Phosphohydrolase/genetics , Pain/etiology , Peritoneal Neoplasms/secondary , Peritoneum/pathology , Phosphatidylinositol 3-Kinases/genetics , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Tumor Suppressor Protein p53/genetics
8.
Ann Oncol ; 27(3): 532-9, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26681675

ABSTRACT

BACKGROUND: Next-generation sequencing (NGS) of tumour samples is a critical component of personalised cancer treatment, but it requires high-quality DNA samples. Routine neutral-buffered formalin (NBF) fixation has detrimental effects on nucleic acids, causing low yields, as well as fragmentation and DNA base changes, leading to significant artefacts. PATIENTS AND METHODS: We have carried out a detailed comparison of DNA quality from matched samples isolated from high-grade serous ovarian cancers from 16 patients fixed in methanol and NBF. These experiments use tumour fragments and mock biopsies to simulate routine practice, ensuring that results are applicable to standard clinical biopsies. RESULTS: Using matched snap-frozen tissue as gold standard comparator, we show that methanol-based fixation has significant benefits over NBF, with greater DNA yield, longer fragment size and more accurate copy-number calling using shallow whole-genome sequencing (WGS). These data also provide a new approach to understand and quantify artefactual effects of fixation using non-negative matrix factorisation to analyse mutational spectra from targeted and WGS data. CONCLUSION: We strongly recommend the adoption of methanol fixation for sample collection strategies in new clinical trials. This approach is immediately available, is logistically simple and can offer cheaper and more reliable mutation calling than traditional NBF fixation.


Subject(s)
DNA/drug effects , Formaldehyde/chemistry , Methanol/chemistry , Neoplasms/diagnosis , Tissue Fixation/methods , Base Sequence , DNA/analysis , High-Throughput Nucleotide Sequencing , Humans , Middle Aged , Paraffin Embedding , Sequence Analysis, DNA
11.
Br J Cancer ; 111(12): 2297-307, 2014 Dec 09.
Article in English | MEDLINE | ID: mdl-25349970

ABSTRACT

BACKGROUND: Folate receptor 1 (FOLR1) is expressed in the majority of ovarian carcinomas (OvCa), making it an attractive target for therapy. However, clinical trials testing anti-FOLR1 therapies in OvCa show mixed results and require better understanding of the prognostic relevance of FOLR1 expression. We conducted a large study evaluating FOLR1 expression with survival in different histological types of OvCa. METHODS: Tissue microarrays composed of tumour samples from 2801 patients in the Ovarian Tumour Tissue Analysis (OTTA) consortium were assessed for FOLR1 expression by centralised immunohistochemistry. We estimated associations for overall (OS) and progression-free (PFS) survival using adjusted Cox regression models. High-grade serous ovarian carcinomas (HGSC) from The Cancer Genome Atlas (TCGA) were evaluated independently for association between FOLR1 mRNA upregulation and survival. RESULTS: FOLR1 expression ranged from 76% in HGSC to 11% in mucinous carcinomas in OTTA. For HGSC, the association between FOLR1 expression and OS changed significantly during the years following diagnosis in OTTA (Pinteraction=0.01, N=1422) and TCGA (Pinteraction=0.01, N=485). In OTTA, particularly for FIGO stage I/II tumours, patients with FOLR1-positive HGSC showed increased OS during the first 2 years only (hazard ratio=0.44, 95% confidence interval=0.20-0.96) and patients with FOLR1-positive clear cell carcinomas (CCC) showed decreased PFS independent of follow-up time (HR=1.89, 95% CI=1.10-3.25, N=259). In TCGA, FOLR1 mRNA upregulation in HGSC was also associated with increased OS during the first 2 years following diagnosis irrespective of tumour stage (HR: 0.48, 95% CI: 0.25-0.94). CONCLUSIONS: FOLR1-positive HGSC tumours were associated with an increased OS in the first 2 years following diagnosis. Patients with FOLR1-negative, poor prognosis HGSC would be unlikely to benefit from anti-FOLR1 therapies. In contrast, a decreased PFS interval was observed for FOLR1-positive CCC. The clinical efficacy of FOLR1-targeted interventions should therefore be evaluated according to histology, stage and time following diagnosis.


Subject(s)
Biomarkers, Tumor/biosynthesis , Folate Receptor 1/biosynthesis , Neoplasms, Glandular and Epithelial/metabolism , Ovarian Neoplasms/metabolism , Carcinoma, Ovarian Epithelial , Disease-Free Survival , Female , Humans , Immunohistochemistry , Middle Aged , Survival Analysis , Tissue Array Analysis
12.
An Pediatr (Barc) ; 80(5): 278-84, 2014 May.
Article in Spanish | MEDLINE | ID: mdl-23856223

ABSTRACT

OBJECTIVE: To assess the renal safety of treatment with polyethylene glycol 3350 with electrolytes at 1, 3 and 6 months, its gastrointestinal tolerance and dose effectiveness. PATIENTS AND METHODS: Three groups of 30 healthy patient aged 2-10 years (mean 6.2 years) who suffered functional constipation (Rome III criteria) with 1, 3 and 6 months of treatment were evaluated. Efficacy was evaluated by the change in the number of stools per week and stool consistency (Bristol scale). Urine screens, sodium and osmolality, were performed at the beginning and after 1, 3 and 6 months of treatment. Stool sample NIRA (near-infrared reflectance analysis) and hydrogen breath test analysis samples were performed on the one-month treatment group. RESULTS: The mean dose was 0.37g/kg/day (range 0.18 to 0.8) titrated according to age, weight and response. The number of stools per week during treatment (2.4±0.64) showed a significant difference (P<.001) vs (6.21±1.5) after treatment. There was also a significant difference in the Bristol scale score (1.9±0.75 vs 4.9±1.1 [P<.001]). The mean sodium intake was 112mg (5mg/kg/day [range 4-12mg/kg/day]). The values of sodium and urine osmolality were normal in all groups with no statistical difference compared to normal control values (90 healthy children without treatment). NIRA values were normal in all patients. The hydrogen breath test was normal with a median of 7ppm. CONCLUSION: There were no adverse renal biochemical parameters or gastrointestinal disorders. Tolerance and efficacy was shown to be optimal. Polyethylene glycol 3350 with electrolytes can be safely recommended for the treatment of functional constipation in children in the short and long term.


Subject(s)
Constipation/drug therapy , Polyethylene Glycols/therapeutic use , Potassium Chloride/therapeutic use , Sodium Bicarbonate/therapeutic use , Sodium Chloride/therapeutic use , Child , Child, Preschool , Cross-Sectional Studies , Drug Therapy, Combination , Humans , Longitudinal Studies , Polyethylene Glycols/adverse effects , Potassium Chloride/adverse effects , Prospective Studies , Retrospective Studies , Sodium Bicarbonate/adverse effects , Sodium Chloride/adverse effects , Time Factors
14.
Br J Cancer ; 104(2): 361-8, 2011 Jan 18.
Article in English | MEDLINE | ID: mdl-21063398

ABSTRACT

BACKGROUND: Intra-tumour genetic heterogeneity has been reported in both leukaemias and solid tumours and is implicated in the development of drug resistance in CML and AML. The role of genetic heterogeneity in drug response in solid tumours is unknown. METHODS: To investigate intra-tumour genetic heterogeneity and chemoradiation response in advanced cervical cancer, we analysed 10 cases treated on the CTCR-CE01 clinical study. Core biopsies for molecular profiling were taken from four quadrants of the cervix pre-treatment, and weeks 2 and 5 of treatment. Biopsies were scored for cellularity and profiled using Agilent 180k human whole genome CGH arrays. We compared genomic profiles from 69 cores from 10 patients to test for genetic heterogeneity and treatment effects at weeks 0, 2 and 5 of treatment. RESULTS: Three patients had two or more distinct genetic subpopulations pre-treatment. Subpopulations within each tumour showed differential responses to chemoradiotherapy. In two cases, there was selection for a single intrinsically resistant subpopulation that persisted at detectable levels after 5 weeks of chemoradiotherapy. Phylogenetic analysis reconstructed the order in which genomic rearrangements occurred in the carcinogenesis of these tumours and confirmed gain of 3q and loss of 11q as early events in cervical cancer progression. CONCLUSION: Selection effects from chemoradiotherapy cause dynamic changes in genetic subpopulations in advanced cervical cancers, which may explain disease persistence and subsequent relapse. Significant genetic heterogeneity in advanced cervical cancers may therefore be predictive of poor outcome.


Subject(s)
Antineoplastic Agents/therapeutic use , Genetic Heterogeneity , Uterine Cervical Neoplasms/genetics , Adult , Aged , Combined Modality Therapy , Female , Humans , Middle Aged , Uterine Cervical Neoplasms/drug therapy , Uterine Cervical Neoplasms/radiotherapy
15.
Clin Transplant ; 25(5): 705-13, 2011.
Article in English | MEDLINE | ID: mdl-21077949

ABSTRACT

Post-transplant lymphoproliferative disorders (PTLD) are potentially fatal complications of solid organ transplantation. The natural history of PTLD varies considerably among the different types of organs transplanted. While lung transplant recipients are highly susceptible to PTLD, there are only a few small studies that detail PTLD in this setting. We undertook this study to better describe the characteristics and treatment response in PTLD after lung transplantation. We conducted a retrospective chart review of lung and heart/lung-transplant recipients between 1985 and 2008. A total of 32 cases (5%) of PTLD were identified in 639 patients. The median interval after transplantation to the diagnosis was 40 (3-242) months. Eight patients (25%) were diagnosed within one yr of transplantation and had PTLD predominantly within the thorax and allograft. Twenty-four patients (75%) were diagnosed more than one yr after transplantation and their tumors mainly affected the gastrointestinal tract. Monomorphic PTLD, diffuse large B-cell lymphoma, was diagnosed in 91%. Treatment of PTLD varied according to stage and clinical circumstances. Twenty-four patients (75%) have died. The median overall survival was 10 (0-108) months. PTLD after lung transplantation remains a challenge as a result of its frequency, complexity and disappointing outcome.


Subject(s)
Heart Transplantation/adverse effects , Lung Transplantation/adverse effects , Lymphoproliferative Disorders/diagnosis , Lymphoproliferative Disorders/etiology , Adult , Aged , Female , Humans , Immunosuppressive Agents/therapeutic use , Lymphoproliferative Disorders/mortality , Male , Middle Aged , Prognosis , Retrospective Studies , Risk Factors , Survival Rate , Transplantation, Homologous , Young Adult
16.
J Appl Microbiol ; 106(2): 592-605, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19200324

ABSTRACT

AIMS: To study the population dynamics of Epicoccum nigrum on peaches and nectarines and to enhance its colonization on fruit surfaces to improve its biocontrol efficacy against brown rot. METHODS AND RESULTS: Twelve surveys were performed to study E. nigrum populations and their effect on the number of the pathogenic Monilinia spp. conidia in peach orchards in Spain and Italy between 2002 and 2005. Fresh conidia and five different formulations of E. nigrum conidia were applied three to six times to peach and nectarine trees from full flowering to harvest. The size of the E. nigrum populations was determined from the number of colony-forming units and conidial numbers per flower or fruit. Treatment with all conidial formulations increased the size of the indigenous conidial population on peach surfaces. CONCLUSIONS: Formulations of E. nigrum having high viability are most effective against conidia of the pathogen when applied at pit hardening and during the month immediately before fruit harvest. SIGNIFICANCE AND IMPACT OF THE STUDY: Application of an E. nigrum conidial formulation decreased the number of conidia of Monilinia spp. on fruit surfaces during the growing season to the same extent as fungicides.


Subject(s)
Antibiosis , Ascomycota/growth & development , Plant Diseases/prevention & control , Prunus/microbiology , Colony Count, Microbial , Fruit/microbiology , Italy , Plant Diseases/microbiology , Population Dynamics , Spain , Spores, Fungal/growth & development
17.
Acta Radiol ; 49(7): 848-51, 2008 Sep.
Article in English | MEDLINE | ID: mdl-19143068

ABSTRACT

Müllerian adenosarcoma of the uterus is a rare biphasic tumor, which was first described in 1974. Recent studies have suggested an association with tamoxifen therapy, but there have been few reports with detailed imaging findings. We present a case with magnetic resonance imaging (MRI) findings of this rare tumor in a woman who received long-term tamoxifen therapy for breast cancer. In addition, myometrial invasion was detected more accurately with MRI compared to ultrasound in this one single case.


Subject(s)
Adenosarcoma/chemically induced , Adenosarcoma/diagnosis , Antineoplastic Agents, Hormonal/adverse effects , Magnetic Resonance Imaging/methods , Mullerian Ducts/pathology , Tamoxifen/adverse effects , Uterine Neoplasms/chemically induced , Uterine Neoplasms/diagnosis , Adenosarcoma/pathology , Adenosarcoma/surgery , Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/drug therapy , Female , Humans , Hysterectomy , Middle Aged , Neoplasm Invasiveness , Tamoxifen/therapeutic use , Uterine Neoplasms/pathology , Uterine Neoplasms/surgery
18.
J Neuroendocrinol ; 19(9): 708-16, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17680886

ABSTRACT

The hypothalamic decapeptide gonadotrophin-releasing hormone (GnRH), modulates gonadotrophin synthesis and secretion and is essential for the preovulatory luteinising hormone (LH) surge. As females age, there is a gradual attenuation and eventual loss of the preovulatory LH surge and oestrous cyclicity. Data from previous studies have demonstrated evidence of compromised GnRH neuronal function at this time. The present study begins to explore the hypothesis that the age-related attenuation of the LH surge and decline in GnRH neuronal function are due, in part, to increased inhibitory influences on GnRH neurones. In situ hybridisation (ISH) was used to assess relative levels of mRNA for one isoform of glutamic acid decarboxylase (GAD), the rate-limiting enzyme for GABA synthesis. Ovariectomised young and middle-aged rats were injected with oestradiol benzoate and progesterone in a regimen for LH surge induction. Animals were killed at time points prior to, during the ascending phase, and during the peak and early descending phase of the LH surge. Dynamic changes in GAD(67) mRNA levels were observed in young but not middle-aged females in two regions known to be important for LH surge induction, the rostral proeptic area in the region of the organum vasculosum of the lamina terminalis (OVLT) and in the ventral periventricular preoptic area. Furthermore, GAD(67) mRNA levels were elevated in middle-aged relative to young females in the region of the OVLT at the time of LH surge induction and in the ventral periventricular preoptic area prior to surge induction. Age-related differences were not observed in other brain regions analysed. These data suggest that GABA synthesis may be elevated in middle-aged relative to young females in specific brain regions at critical times in conjunction with the LH surge, and that the lack of dynamic changes in GABA levels in these regions may contribute to the attenuated LH surge observed in middle-aged females.


Subject(s)
Aging/physiology , Estrous Cycle/physiology , Glutamate Decarboxylase/genetics , Isoenzymes/genetics , Luteinizing Hormone/blood , RNA, Messenger/metabolism , Animals , Female , Hypothalamus/cytology , Hypothalamus/metabolism , In Situ Hybridization , Rats , Rats, Sprague-Dawley , gamma-Aminobutyric Acid/metabolism
19.
Oncología (Barc.) ; 26(9): 293-298, sept. 2003.
Article in Es | IBECS | ID: ibc-26392

ABSTRACT

- Propósito: se revisan los datos epidemiológicos, clínicos, anatomopatológicos y los procedimientos diagnósticos y terapéuticos de los ameloblastomas maxilares.- Material y métodos: se presenta un caso de ameloblastoma de maxilar superior en una mujer de 36 años.- Resultados: se realizó tratamiento con radioterapia postoperatoria tras cirugía radical, dado que se trataba de una lesión extensa en una paciente joven. Tras un seguimiento de 5 años y medio la paciente se encuentra libre de enfermedad.- Conclusiones: se describe el comportamiento de este tumor así como su tratamiento (AU)


Subject(s)
Adult , Female , Humans , Ameloblastoma/complications , Ameloblastoma/diagnosis , Ameloblastoma/radiotherapy , Mandibular Neoplasms/diagnosis , Mandibular Neoplasms/radiotherapy , Maxillary Neoplasms/diagnosis , Maxillary Neoplasms/radiotherapy , Ameloblastoma/epidemiology , Ameloblastoma/physiopathology , Ameloblastoma/therapy , Tomography, Emission-Computed/methods , Biopsy/methods , Postoperative Care/methods
20.
J Appl Microbiol ; 94(3): 508-14, 2003.
Article in English | MEDLINE | ID: mdl-12588560

ABSTRACT

AIMS: The effects of freeze-drying, spray-drying and fluidized bed-drying on survival of Epicoccum nigrum conidia were compared. METHODS AND RESULTS: Viability of E. nigrum conidia (estimated by measuring its germination) was 100% after fluidized bed-drying and freeze-drying, but it was determined that skimmed milk must be added in the case of freeze-drying conidia. Addition of other protectants (Tween-20, peptone, sucrose, glucose, starch and peptone + starch) to skimmed milk before freeze-drying did not improve the conidial viability which was obtained with skimmed milk alone. Glycerol had a negative effect on the lyophilization of E. nigrum conidia. Epicoccum nigrum conidia freeze-dried with skimmed milk, or fluidized bed-dried alone maintained an initial viability for 30 and 90 days, respectively, for storage at room temperature. Epicoccum nigrum conidial viability after spray-drying was lower than 10%. CONCLUSIONS: The best method to dry E. nigrum conidia was fluidized bed-drying. Conidia without protectants dried by this method had 100% viability and survived for 90 days at room temperature. SIGNIFICANCE AND IMPACT OF STUDY: This paper deals with methods for the potential formulation of a biocontrol agent which is being tested for eventual commercialization.


Subject(s)
Ascomycota , Biological Factors , Desiccation/methods , Plant Diseases/microbiology , Freeze Drying/methods , Pest Control, Biological , Temperature
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