1,720,979 research outputs found
Interactions between Bacillus amyloliquefaciens AG1 and Aspergillus spp. contaminating food and feedstuffs
No full textAspergillus is a widespread fungal genus contaminating and degrading food and feeds mostly during storage. Some species can also produce carcinogenic mycotoxins harmful for human and animal health. In this study, Bacillus amyloliquefaciens AG1 (BaAG1), active against fungal pathogens was evaluated by in vitro tests against seven Aspergillus species belonging to six Aspergillus sections. After 7 days of incubation at 25°C, mycelial growth of all fungal species was reduced from 46.53% to 60.92%, compared to the controls. The inhibitory effect of BaAG1 cell-free culture filtrate was tested by turbidimetric measurements by using ScanReady P-800 that allow the automatic and continuous monitoring of the changes in the O.D. of fungal growth over time. Two culture mediums for growth curve optimization were tested, and PDB (Potato Dextrose Broth) was selected. The activity of two concentration of BaAG1 cell-free culture filtrate against three strains (Aspergillus niger SAAF 7, A. flavus SAAF 43 and A. fumigatus SAAF 47) was assessed over 7 d periods with automated measurements every 60 min. Significant differences in AUC (area under growth curve) were recorded between the treatments and the controls. Furthermore, macro and microscopic observation on the fungal colonies showed that both the concentrations of BaAG1 culture filtrates induced morphological changes, such as absence of conidiophores and conidia, presence of cleistothecia and hyphal alterations
Fungi Associated with Olive Tree (cv. ‘Nocellara del Belice’) Decay in Trapani Province (Sicily, Italy)
Full text linkRecently, in several locations in the province of Trapani (Sicily, Italy), olive growers have reported cases of decaying olive trees of cv. ‘Nocellara del Belice’, showing symptoms of defoliation, branch drying, xylem browning, and reduced production. Internal symptoms include white and brown wood rot, starting from the base of the trunk. These alterations have been observed in trees irrigated using a pipe system at the trunk with spray sprinklers. To identify the causal agents of decay, some trees were eradicated and dissected, and woody samples were processed to isolate and identify the associated fungal micro-organisms. The most common colonies were identified using morphological (macro- and microscopical observation) and molecular (PCR amplification of the rDNA-ITS region) analyses. Nine fungal taxa were identified, of which four were associated with this decay syndrome (Coriolopsis gallica, Fomitiporia mediterranea, Kirschsteiniothelia sp., and Pleurostoma richardsiae), three were considered ubiquitous and opportunistic fungi (Alternaria spp., Aspergillus amstelodami, and Trichoderma sp.), and the other two were mycelia sterilia. Artificial inoculation satisfied Koch’s postulates, confirming the pathogenicity of the aforementioned fungi, even though the infections in the fields seem to be related to the irrigation system. This hypothesis would seem to be confirmed by the progression of decay over time in the trees subjected to the irrigation system described but not reported in olive groves differently managed. It is therefore considered appropriate to conduct further and more in-depth investigations aimed at studying the correlation between the irrigation system, presence of fungal agents, and manifestation of the syndrome. A further ongoing investigation is aimed at the use of biostimulants (Agrusaver, Savory Sun, VA LLC) on symptomatic trees, with the aim of both improving the vegetative performance of the host and limiting the symptoms detected in the field
Fungal contaminants in Sicilian livestock feeds and first studies on the enzymatic activity of Aspergillus isolates
Full text linkThe purposes of this study were 1) to determine the total fungal contamination in Sicilian raw materials and livestock, 2) to evaluate the occurrence of Aspergillus spp., Penicillium spp. and Fusarium spp., 3) to identify fungi belonging to the genus Aspergillus and 4) to determine their ability to produce cellulolytic enzymes. Fourteen feed samples were collected in a feed mill near to Palermo (Sicily, Italy). Analysis of the total mycobiota was performed on Sabourad Dextros Agar (SAB) and Potato Dextrose Agar (PDA) and total fungal counts were expressed as CFU/g. Aspergillus spp. isolates were selected on the basis of the frequency of isolation and identifed using micro and macro-morphological characteristics and ITS sequence analysis. The ability of the Aspergillus isolates to produce cellulolytic enzymes was tested qualitatively by in vitro assay at two temperature, 25 and 30 °C, and in static and shaking condition. Total fungal population ranged from 1.11x106 to 1.31x108 and from 1.11x103 to 1.58x106 CFU/g on PDA and SAB, respectively. All feed samples showed the recurrent presence of colonies belonging mostly to the ubiquitous genera Aspergillus, Fusarium and Penicillium. Eight isolates of Aspergillus spp. were obtained and identifed as A. amstelodami, A. awamori, A. flavus, A. niger, A. oryzae and A. tubingensis. Between them, A. awamori, A. niger and A. tubingensis showed the highest enzymatic activity. The presence of potential mycotoxigenic isolates of Aspergillus spp. in the analysed feeds represents a risk for animal health; moreover their ability to produce cellulolytic enzymes can seriously affect feed quality
Statice tenuicula Guss., Fl. Sic. Prodr.
No full text12. Statice tenuicula Tineo ex Guss., Fl. Sic. Prodr. suppl. 1: 90(–91). 1832. ≡ Limonium tenuiculum (Tineo ex Guss.) Pignatti, Bot. J. Linn. Soc. 64: 365. 1971. Ind. Loc.: —“Maretimo”. Lectotype (here designated):—[Sicily] Statice tenuiculum Nob., Marettimo, 1832, V. Tineo (NAP0001792 Photo!). Note:— There are two specimens at FI (barcodes FI002299 and FI002300) collected by V. Tineo in Marettimo, but without collection date. The specimen PAL60382 was collected in Marettimo in June (no year of collection was reported) by V. Tineo. Finally, a specimen at NAP (barcode NAP0001792), collected by Tineo in Marettimo, is dated (year 1832); it includes one individual with flowers. A furthe NAP specimen (NAP0001793) was collected the 10 May 1829, but it includes an individual without flowers. NAP0001792 (date and with flowers) is here designate as lectotype of the name Statice tenuicula; it fits the original description and corresponds to the current use of the name that applies to a species strictly endemic to the island of Marettimo (Brullo & Brullo 2020).Published as part of Barone, Giulio, Domina, Gianniantonio, Gristina, Emilio Di, Mirabile, Giulia & Gargano, Maria Letizia, 2023, Typification of names published by Vincenzo Tineo from Sicily, pp. 139-147 in Phytotaxa 612 (2) on page 144, DOI: 10.11646/phytotaxa.612.2.2, http://zenodo.org/record/832346
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Primi studi sull'interazione tra stato di micorrizazione e danni da incendio in una pineta siciliana
Full text linkNell’ambito di uno studio sulle simbiosi micorriziche delle conifere in ambienti siciliani, è stata avviata un’indagine preliminare sulla interazione tra danni da incendio e stato di micorrizazione in un rimboschimento artificiale di Pinus halepensis Mill. In particolare, nel bosco di Casaboli (Monreale, PA) estesamente interessato da incendi dolosi nell’estate 2017, sono state delimitate tre aree contigue di circa 700 m2, comprendenti una ventina di piante coetanee (30-40 anni) e con differente entità di danno: 1) vegetazione apparentemente sana (S); danni di media entità (M); danni ingenti (I). In ogni area, dopo aver condotto opportuni rilievi dendrometrici, sono stati individuati 5 punti per il prelievo di carote di suolo a due profondità (5-15; 20-30 cm); i campionamenti sono stati ripetuti tre volte nel biennio 2018-19 (giugno e novembre 2018, maggio 2019) e saranno completati a novembre 2019. I frammenti radicali di P. halepensis, recuperati sotto un leggero flusso d’acqua corrente, sono stati osservati allo stereo microscopio, valutando l’Indice di Micorrizazione (IM = n° totale di apici micorrizici/cm di radice) e rilevando, sul numero totale di apici micorrizici, la percentuale di quelli attivi e non (necrotici). Sebbene l’indagine sia ancora in corso, i primi risultati sembrerebbero evidenziare valori di IM maggiori nell’area S, decrescenti in funzione del livello di deperimento. Nel contempo, nel profilo di suolo compreso tra 20 e 30 cm sono stati rilevati i maggiori livelli di micorrizazione, che rimane sensibile anche nelle aree più danneggiate. Ulteriori dati acquisiti nel corso dell’attività di ricerca potranno fornire utili indicazioni per la definizione degli effetti di tale fattore di disturbo nell’ecosistema oggetto di studio
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Attacks of Kalotermes flavicollis Fabricius (1793) and Associated Aspergillus Micheli ex Haller (1768) Species
Full text linkThe yellow-necked dry-wood termite Kalotermes flavicollis (Fabricius, 1793) (Blattodea: Kalotermitidae) is an important pest that infests wood in Europe. An increase in attacks by K. flavicollis has been seen in buildings and in churches in Palermo (Italy), with attacks on both structural elements and artefacts. Future climate changes are expected to lead to increasing temperatures, which will probably affect the pest status of this species, which is difficult to control. In this context, it is important to identify potential natural antagonists of K. flavicollis. During a survey of the K. flavicollis population, several dead individuals with evident fungal efflorescence were found. Therefore, a study aimed at the isolation and identification of these microorganisms was conducted. Fungal colonies isolated from mycelial structures grown on insects were identified based on morphological characteristics and DNA profiling. Three different species were identified: Aspergillus nomius, A. subramanianii, and A. tamarii. This is the first time that fungi have been recorded in association with the yellow-necked dry-wood termite and, in addition, this study reports the first association of A. subramanianii with Isoptera
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