Spray Drying of Chitosan Acid Salts: Process Development,Scaling Up and Physicochemical Material Characterization     

Nilia de la Paz  Mirna Fernndez  Orestes Lpez  Caridad Garcia  Antonio Nogueira  Leonid Torres  Wilfredo Turio  Jyrki Heinmki 《Marine drugs》2021,19(6)

We investigated a spray drying process for preparing water-soluble salts of high molecular weight chitosan (CH) intended for pharmaceutical excipient applications. CH was derived from chitin of marine lobster origin (Panulirus argus). The effects of organic acid (acetic or lactic acid) and the ratio (difference) of inlet/outlet air temperature (140/90 °C or 160/100 °C) on spray drying were studied. The yield of spray-dried CH salt powders ranged from 50% to 99% in laboratory and industrial-scale processes. The spray-dried dry powder of CH salts consisted of spherical agglomerated particles with an average diameter of 36.2 ± 7.0 µm (CH acetate) and 108.6 ± 11.5 µm (CH lactate). After dispersing the spray-dried CH salt powder samples in purified water, the mean particle sizes obtained for the CH acetate salts were 31.4 nm (batch A001), 33.0 nm (A002) and 44.2 nm (A003), and for the CH lactate salts 100.8 nm (batch L001), 103.2 nm (L002) and 121.8 nm (L003). The optimum process conditions for spray drying were found: an inlet air temperature of 160 ± 5 °C, an outlet temperature of 100 ± 5 °C and an atomizer disk rotational speed of 18,200 min⁻¹. The X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC) results confirmed the amorphous state of the CH salts. The ¹H nuclear magnetic resonance (NMR) and Fourier transform infrared (FT-IR) spectra of CH acetate and lactate salts verified that the spray drying process does not affect the polymer backbone. In conclusion, both laboratory and industrial-scale spray drying methods for preparing water-soluble acid salts of CH are reproducible, and the physicochemical properties of the corresponding CH acid salts are uniform.  相似文献   

Co-inoculation of soybeans and common beans with rhizobia and azospirilla: strategies to improve sustainability     

Mariangela Hungria  Marco Antonio Nogueira  Ricardo Silva Araujo 《Biology and Fertility of Soils》2013,49(7):791-801

Plant–microorganism associations have long been studied, but their exploitation in agriculture partially or fully replacing chemical fertilizers is still modest. In this study, we evaluated the combined action of rhizobial and plant growth-promoting rhizobacteria inoculants on the yields of soybean and common bean. Seed inoculation with rhizobia (1.2?×?10⁶ cells seed^?1) was compared to co-inoculation with Azospirillum brasilense in-furrow (different doses) or on seeds (1.2?×?10⁵ cells seed^?1) in nine field experiments. The best in-furrow inoculant dose was 2.5?×?10⁵ cells of A. brasilense seed^?1 for both crops. Inoculation with Bradyrhizobium japonicum increased soybean yield by an average 222 kg?ha^?1 (8.4 %), and co-inoculation with A. brasilense in-furrow by an average 427 kg?ha^?1 (16.1 %); inoculation always improved nodulation. Seed co-inoculation with both microorganisms resulted in a mean yield increase of 420 kg?ha^?1 (14.1 %) in soybean relative to the non-inoculated control. For common bean, seed inoculation with Rhizobium tropici increased yield by 98 kg?ha^?1 (8.3 %), while co-inoculation with A. brasilense in-furrow resulted in the impressive increase of 285 kg?ha^?1 (19.6 %). The cheaper, more sustainable inoculated treatment produced yields equivalent to the more expensive non-inoculated + N-fertilizer treatment. The results confirm the feasibility of using rhizobia and azospirilla as inoculants in a broad range of agricultural systems, replacing expensive and environmentally unfriendly N-fertilizers.  相似文献   

Fusarium tricinctum associated with Head Blight on barley in Argentina: pathogenicity and potential degradation of the different hordein fractions     

Martínez  Mauro  Dinolfo  María I.  Nogueira  Soledad  Stenglein  Sebastián A. 《植物病害和植物保护杂志》2021,128(5):1377-1381

Journal of Plant Diseases and Protection - The objective of the present work was to evaluate the pathogenicity of Fusarium tricinctum in barley and to determine the potential effects on grain...  相似文献   

The control of polyphenol oxidase activity in fruits and vegetables   总被引：5，自引：0，他引：5  

M. E. M. Almeida  J. N. Nogueira 《Plant foods for human nutrition (Dordrecht, Netherlands)》1995,47(3):245-256

Objective of this research was to find alternative methods for the control of polyphenol oxidase (PPO) activity in fruits and vegetables with the purpose of reducing or eliminating the use of SO₂ for this purpose. Interactions between the use of ascorbic acid, citric acid, EDTA, sodium metabisulphite and heat treatment (70 °C for 2 min) in the control of PPO activity were studied in avocado (var. Fortuna), banana (var. Nanica), apple (var. Ana, Fuji, Gala & Golden), pear (var. D'Agua), peach (var. Real), potato (var. Bintje), eggplant (var. Super F100), mushroom (Agaricus bisporus) and hearts-of-palm (Euterpe edulis Mart.). The results demonstrated that PPO of avocado and eggplant was most resistant to inhibition by the methods used. The least efficient method tested for the control of PPO was the addition of ascorbic acid and EDTA, while the most efficient methods investigated included the use of ascorbic acid, citric acid, sodium metabisulphite and heat treatment. The results indicated that, with the exception of PPO from avocado, the most adequate alternative method to substitute for the use of SO₂ in the control of PPO was a combination of ascorbic acid, citric acid and heat treatment.  相似文献   

Standard non-target tests for risk assessment of plant protection products are unsuitable for entomopathogenic fungi—a proposal for a new protocol     

Reinbacher  Lara  Bacher  Sven  Praprotnik  Eva  Grabenweger  Giselher 《Journal of Soils and Sediments》2021,21(6):2357-2368

Journal of Soils and Sediments - The successful implementation of a plant protection product depends on its effectiveness against a target species and its safety for the environment. Risk...  相似文献   

Two cases of feline visceral and cutaneous leishmaniosis in Spain     

Hervás J  Chacón-M De Lara F  Sánchez-Isarria MA  Pellicer S  Carrasco L  Castillo JA  Gómez-Villamandos JC 《Journal of Feline Medicine and Surgery》1999,1(2):101-105

This paper describes clinical signs and lesions in two cases of leishmaniosis--one visceral and one cutaneous in the cat (Felis catus domesticus). The diagnosis was achieved by a combination of serology, light and electron microscopic studies. The vague nature of the clinical signs observed in both cases was particularly striking, and clinical features were similar to many other diseases commonly found in cats. Therefore, the use of various investigations to detect leishmaniosis (serum chemistry, serology and histopathology) is highly recommended in cases where clinical signs do not respond to conventional treatment.  相似文献   

Estimates of forest biomass in the Brazilian Amazon: New allometric equations and adjustments to biomass from wood-volume inventories   总被引：1，自引：0，他引：1  

Euler Melo Nogueira  Philip Martin Fearnside  Bruce Walker Nelson  Reinaldo Imbrozio Barbosa  Edwin Willem Hermanus Keizer 《Forest Ecology and Management》2008

Uncertainties in biomass estimates in Amazonian forests result in a broad range of possible magnitude for the emissions of carbon from deforestation and other land-use changes. This paper presents biomass equations developed from trees directly weighed in open forest on fertile soils in the southern Amazon (SA) and allometric equations for bole-volume estimates of trees in both dense and open forests. The equations were used to improve the commonly used biomass models based on large-scale wood-volume inventories carried out in Amazonian forest. The biomass estimates from the SA allometric equation indicate that equations developed in forests on infertile soils in central Amazonia (CA) result in overestimates if applied to trees in the open forests of SA. All aboveground components of 267 trees in open forests of SA were cut and weighed, and the proportion of the biomass stored in the crowns of trees in open forest was found to be higher than in dense forest. In the case of inventoried wood volume, corrections were applied for indentations and hollow trunks and it was determined that no adjustment is needed for the form factor used in the RadamBrasil volume formula. New values are suggested for use in models to convert wood volume to biomass estimates. A biomass map for Brazilian Amazonia was produced from 2702 plots inventoried by the RadamBrasil Project incorporating all corrections for wood density and wood volume and in factors used to add the bole volume of small trees and the crown biomass. Considering all adjustments, the biomass map indicates total biomass of 123.1 Gt (1 Gt = 1 billion tons) dry weight (aboveground + belowground) for originally forested areas in 1976 in the Brazilian Legal Amazon as a whole (102.3 Gt for aboveground only) at the time of the RadamBrasil inventories, which were carried out before intensive deforestation had occurred in the region. Excluded from this estimate are 529,000 km² of forest lacking sufficient RadamBrasil inventory data. After forest losses of 676,000 km² by 2006 – not counting 175,000 km² of this deforested area lacking RadamBrasil data – the estimated dry biomass stock was reduced to 105.4 and 87.6 Gt (aboveground + belowground and only above-ground). Thus, in 2006 the carbon storage in forested areas in Brazilian Amazonia as a whole will be around 51.1 Gt (assuming 1 Mg dry biomass = 0.485 Mg C). Biomass estimates by forest type (aggregated into 12 vegetation classes) are provided for each state in the Brazilian Legal Amazon.  相似文献   

Bioprospecting of Less-Polar Fractions of Ericaria crinita and Ericaria amentacea: Developmental Toxicity and Antioxidant Activity     

Sanja Radman  Lara imek  Sanja Babi&#x;  Ana-Marija Ciko&#x;  Rozelindra o-Rakovac  Stela Joki&#x;  Igor Jerkovi&#x; 《Marine drugs》2022,20(1)

Ericaria crinita and Ericaria amentacea from the Adriatic Sea (Croatia) were investigated with respect to the presence of less-polar compounds for the first time after fractionation by solid-phase extraction (SPE). The composition of less-polar fractions of freeze-dried E. crinita (FdEc) and E. amentacea (FdEa) were analyzed by high-performance liquid chromatography–high-resolution mass spectrometry with electrospray ionization (UHPLC-ESI-HRMS). The major identified compounds were: amides of higher aliphatic acids (palmitoleamide, linoleamide, palmitamide, oleamide and erucamide) and related compounds, carotenoid (fucoxanthin), chlorophyll derivatives (pheophytin a and b and their derivatives) and higher terpenes (loliolide, isoamijiol with its oxidation product), β-stigmasterol and (3β,6α)-14-methylergosta-8,24(28)-diene-3,6-diol). The toxic effects observed on the less-polar fractions obtained from Ericaria species on zebrafish Danio rerio embryos could be associated with the high abundance of all five detected amides. The antioxidant activity of the fractions was evaluated by means of five independent assays, including the reduction of the radical cation (ABTS), the oxygen radical absorbance capacity (ORAC), ferric-reducing antioxidant power (FRAP), the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay and the Folin–Ciocalteu method. A higher antioxidant activity of E. amentacea in comparison to that of the E. crinita fractions was found with IC₅₀ concentrations of 0.072 and 1.177 mg/mL, respectively. The correlation between the activity and the chemical composition revealed that the synergistic effect of different compounds impacted their antioxidant response.  相似文献   

Effects of Cocoa-Derived Polyphenols on Cognitive Function in Humans. Systematic Review and Analysis of Methodological Aspects     

Barrera-Reyes  Paloma K  de Lara  Josué Cortés-Fernández  González-Soto  Melissa  Tejero  M Elizabeth 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):1-11

Plant Foods for Human Nutrition - The effects of cocoa-derived polyphenols on cognitive functions have been analyzed through numerous studies using different interventions (doses, vehicles, time...  相似文献   

Hybridisation in kiwi (Apteryx; Apterygidae) requires taxonomic revision for the Great Spotted Kiwi     

Lara D.Shepherd  Alan J.D.Tennyson  Hugh A.Robertson  Rogan M.Colbourne  Kristina M.Ramstad 《中国鸟类》2021,(2):195-207

Background: Kiwi (Apteryx spp.) are flightless ratites from New Zealand whose numbers and distributions have declined following human arrival. Some of the kiwi ...  相似文献