Search results for "CLASSIFICATION"
showing 10 items of 29475 documents
Understanding the Effects of Crosslinking and Reinforcement Agents on the Performance and Durability of Biopolymer Films for Cultural Heritage Protec…
2021
In the last two decades, the naturally occurring polysaccharides, such as chitosan and pectin, have gained great attention having potential applications in different sectors, from biomedical to new generation packaging. Currently, the chitosan and pectic have been proposed as suitable materials also for the formulation of films and coatings for cultural heritage protection, as well as packaging films. Therefore, the formulation of biopolymer films, considering only naturally occurring polymers and additives, is a current challenging trend. This work reports on the formulation of chitosan (CS), pectin (PC), and chitosan:pectin (CS:PC) films, also containing natural crosslinking and reinforce…
Coupling tyrosol, quercetin or ferulic acid and electron beam irradiation to cross-link chitosan–gelatin films: A structure–function approach
2015
International audience; Marine industry by-products, chitosan and fish gelatin, entrapping natural antioxidants (ferulic acid, quercetin and tyrosol) were used to prepare edible active films by casting. The films were composed of chitosan and fish gelatin (1:1 w:w) and incorporating antioxidants (∼50 mg/g). After solvent evaporation (drying), the films were irradiated at 60 kGy by electron beam. This treatment aims at investigating the coupled effect of irradiation with the presence of active compound on the structure and functional properties of the films. Electron Spin Resonance (ESR) unravelled free radical formation during irradiation in films containing ferulic acid or tyrosol which fa…
Bionanocomposite films containing halloysite nanotubes and natural antioxidants with enhanced performance and durability as promising materials for c…
2020
In the last decade, the interest toward the formulation of polymer films for cultural heritage protection continuously grew, and these films must be imperatively transparent, removable, and should not react/interact with surface of the artworks. In this research, bionanocomposite films, based on chitosan (Ch) and pectin (P) and containing naturally occurring fillers and antioxidants, were formulated by solvent casting methods and were accurately characterized. The natural halloysite nanotubes (HNT) have a two-fold role, specifically, physical compatibilizer and antioxidant carrier. Therefore, the theoretical solubility between Ch and P was estimated considering Hoy&rsquo
Non-Botrytis grape-rotting fungi responsible for earthy and moldy off-flavors and mycotoxins
2012
Abstract The grape microflora is complex and includes filamentous fungi, yeasts and bacteria with different physiological characteristics and effects on wine production. Most studies have focused on the wine microbiota, but a few studies have reported the ecology of grape microorganisms. Some of these organisms — such as non-Botrytis bunch rotting fungi, which greatly influence the safety or sensory quality of wine, due to the production of mycotoxins and off-flavors, respectively — are considered to be spoilage agents. We review here the diversity of filamentous fungi on grapes and the factors influencing their development, such as grape ripening stage, environmental factors (climate, rain…
Involvement of an Alkane Hydroxylase System of Gordonia sp. Strain SoCg in Degradation of Solid n-Alkanes▿
2010
ABSTRACT Enzymes involved in oxidation of long-chain n -alkanes are still not well known, especially those in Gram-positive bacteria. This work describes the alkane degradation system of the n -alkane degrader actinobacterium Gordonia sp. strain SoCg, which is able to grow on n -alkanes from dodecane (C 12 ) to hexatriacontane (C 36 ) as the sole C source. SoCg harbors in its chromosome a single alk locus carrying six open reading frames (ORFs), which shows 78 to 79% identity with the alkane hydroxylase (AH)-encoding systems of other alkane-degrading actinobacteria. Quantitative reverse transcription-PCR showed that the genes encoding AlkB (alkane 1-monooxygenase), RubA3 (rubredoxin), RubA4…
Antimicrobial and Antioxidant Activities of Coumarins from the Roots of Ferulago campestris (Apiaceae)
2009
We report the isolation of several coumarins and the stereochemical assessment of some pyranocoumarins, as well as the antibacterial and antioxidant activities of the three most abundant ones (grandivittin, agasyllin and aegelinol benzoate) isolated from the roots of Ferulago campestris collected in Sicily and of the hydrolysis product (aegelinol). Aegelinol and agasyllin showed antibacterial activity against nine ATCC and the same clinically isolated Gram-positive and Gram-negative bacterial strains. At a concentration between 16 and 125 μg/mL both coumarins showed a significant antibacterial effect against both Gram-negative and Gram-positive bacteria. In particular the ATCC strains Staph…
Pythium contiguanum nomen novum (syn. Pythium dreschleri Paul), its antagonism to Botrytis cinerea, ITS1 region of its nuclear ribosomal DNA, and its…
2000
Pythium drechsleri Paul was described as a new species from soil samples taken in a salt-marsh of Arzew, Algeria [Paul, B. (1988) Une nouvelle espece de Pythium isolee d'une saline de l'ouest Algerien. Cryptogam. Mycol. 9, 325-333]. The name of the fungus, P. drechsleri, is a nomen invalidum, as it is a later homonym of P. drechsleri Rajgopalan and Ramakrishnan [Rajagopalan, S. and Ramakrishnan, K. (1971) Phycomycetes in agricultural soils with special reference to the Pythiaceae. Madras Univ. J. Sect. B 37,38, 100-117]. A new name, Pythium contiguanum is now being given to P. drechsleri Paul. This species is characterised by its contiguous inflated type of sporangia, smooth-walled oogonia …
Essential Oil Composition of the Aerial Parts of FiveOcimumspecies from Western India
2015
AbstractChemical composition of the essential oils of five Ocimum species namely Ocimum tenuiflorum syn Ocimum sanctum L. (green and purple), Ocimum kilimandscharicum Guerke, Ocimum viride Willd, Ocimum basilicum L. and Ocimum gratissimum L., obtained by a hydrodistillation was determined by GC and GC-MS. A total of one hundred three compounds were identified in the oils of five Ocimum species, of which fifteen compounds were found to be major (5.0–81.8 %) compounds. Analysis of Ocimum viride oil showed the highest amount of eugenol (81.8 %) among species besides germacrene D (7.0 %) and cis-ocimene (4.1 %). Ocimum tenuiflorum green and Ocimum tenuiflorum purple were found contain eugenol (…
Maternal antibody transmission and breeding densities in the Black-headed Gull Larus ridibundus
2004
1. The offspring of avian species, especially those of colonial breeders, are exposed to a number of pathogens immediately after birth. The chick's immune system is, at that early stage still immature and inefficient. As a consequence, diseases can have a strong impact on chick survival.2. The ability of mothers to transmit passive immunity in terms of antibodies of their own acquired immunity to their chicks is probably an essential pathway to enhance the chick survival. Since the production of antibodies is costly, females are expected to adjust the transmission of passive immunity to the local disease environment.3. We found that in Black-headed Gulls (Larus ridibundus L.) yolk antibody …
Performance of Host-Races of the Fruit Fly,Tephritis conuraon a Derived Host Plant, the Cabbage ThistleCirsium oleraceum: Implications for the Origin…
2008
The thistle-infesting fruit fly Tephritis conura Loew (Diptera: Tephritidae) forms host races on the melancholy thistle, Cirsium hetewphyllum (L.) Hill (Asterales: Asteraceae) and the cabbage thistle, Cirsium olemceum (L.). Scop. Previous research indicates that the host shift occurred from C. hetewphyllum to C. oleraceum. In this paper we address whether the host shift involved physiological adaptations by studying oviposition acceptance and survival of the two host races on the derived host C. oleraceum. Performance differed significantly between host races. T. conura originating from C. oleraceum produced adults in 75% of all egg-laying trials in contrast to only 6.6% in T. conura origin…