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651.
Isolation and properties of a Kunitz-type protein inhibitor obtained from Pithecellobium dulce seeds
Delgado-Vargas F López-Valdés HE Valdés-Rodríguez S Blanco-Labra A Chagolla-López A López-Valenzuela Ede J 《Journal of agricultural and food chemistry》2004,52(20):6115-6121
We report for the first time the isolation and characterization of a protease inhibitor from the seeds of Pithecellobium dulce, which is a Leguminosae tree native to Mexico. The purification of the P. dulce trypsin inhibitor (PDTI) was a direct process. After its extraction (pH 8.0) and precipitation (80% (NH(4))(2)SO(4)), the pH was adjusted to 4.0, the supernatant was loaded onto a CM-Sepharose column, and a single peak of trypsin inhibitory activity was eluted (CM-TIA). The main component of CM-TIA was PDTI, a protein composed of two polypeptide chains joined by disulfide bridge(s), with a pI of 4.95 and a molecular weight determined by electrospray mass spectrometry of 19 614 Da. The N-terminal sequence of PDTI has the highest similarity with the seed inhibitor of Acacia confusa. PDTI lacks chymotrypsin inhibitory activity. A low rate of cytotoxicity of CM-TIA toward RINm5F cells contrasted with a high rate of the active fraction G75-TIA (gel filtration chromatography; LC(50) of 0.04 mg/mL). 相似文献
652.
Juan Manuel Audelo‐Naranjo Luis Rafael Martínez‐Crdova Domenico Voltolina Silvia Gmez‐Jimnez 《Aquaculture Research》2011,42(9):1371-1377
The effect of artificial substrates on the water quality, production parameters and nutritional condition was assessed in experimental intensive cultures of Litopenaeus vannamei grown in mesocosm units with zero water exchange. The initial stocking densities in triplicate 1000 L tanks were 600 and 800 g of juvenile shrimp (2.7 g) per unit, with (W) and without (WO) artificial substrates. There were no significant differences between the water quality parameters of the four treatments. In the tanks with the lower stocking biomass, the best survival (96.7% vs. 87.0%), growth rate (1.69 vs. 1.35 g week−1), final biomass (1969.6 vs. 1516.0 g m3) and feed conversion ratio (1.30 vs. 1.90) were obtained with artificial substrates. Similar results were observed for the higher stocking biomass (90.9% vs. 74.5%, 1.50 vs. 1.13 g week−1, 2221.6 vs. 1560.8 g m3, and 1.50 vs. 2.60 respectively). The nutritional condition of shrimp was improved using artificial substrates. The protein content in muscle was higher (21.6% and 20.4%) in ponds with substrates as compared with the control (21.2% and 15.9%). 相似文献
653.
Sabry M. Youssef Silvia Jiménez-Bermúdez M. Luz Bellido Carmen Martín-Pizarro Marta Barceló Samia Abdallah Abdal-Aziz José L. Caballero José M. López-Aranda Fernando Pliego-Alfaro Juan Muñoz Miguel A. Quesada José A. Mercado 《Scientia Horticulturae》2009
Two transgenic strawberry lines (Pel 1 and Pel 3) containing the open reading frame of a fruit specific strawberry pectate lyase gene (FaplC) under the control of the CaMV35S promoter have been obtained to evaluate the role of this gene on fruit softening. Ripen fruits from both lines showed a significant down-regulation of FaplC, being the percentage of silencing of 84 and 71% on Pel 1 and Pel 3, respectively. The agronomic behaviour of transgenic plants was evaluated during two consecutive years. Fruit set increased in the two transgenic lines when compared with control plants, although Pel 1 showed a significant reduction on fruit weight. Firmness of full ripen fruits from Pel lines was significantly higher than control fruits, while color and soluble solids were not affected. The increase of firmness in Pel lines was maintained when ripe fruits were stored for 3 days at 25 °C. Histological analysis of ripe fruits showed lower intercellular spaces and a higher degree of cell to cell contact area in transgenic fruits when compared with controls. Altogether, these results suggest a direct relationship between pectate lyase gene expression and strawberry fruit softening. 相似文献
654.
Nowadays, seaweeds are widely involved in biotechnological applications. Due to the variety of bioactive compounds in their composition, species of phylum Ochrophyta, class Phaeophyceae, phylum Rhodophyta and Chlorophyta are valuable for the food, cosmetic, pharmaceutical and nutraceutical industries. Seaweeds have been consumed as whole food since ancient times and used to treat several diseases, even though the mechanisms of action were unknown. During the last decades, research has demonstrated that those unique compounds express beneficial properties for human health. Each compound has peculiar properties (e.g., antioxidant, antimicrobial, antiviral activities, etc.) that can be exploited to enhance human health. Seaweed’s extracted polysaccharides are already involved in the pharmaceutical industry, with the aim of replacing synthetic compounds with components of natural origin. This review aims at a better understanding of the recent uses of algae in drug development, with the scope of replacing synthetic compounds and the multiple biotechnological applications that make up seaweed’s potential in industrial companies. Further research is needed to better understand the mechanisms of action of seaweed’s compounds and to embrace the use of seaweeds in pharmaceutical companies and other applications, with the final scope being to produce sustainable and healthier products. 相似文献
655.
Gomez Hector Alonzo Gomez Marques Marcia Ortiz Mayo Borges Cristine Vanz Minatel Igor Otavio Monteiro Gean Charles Ritschel Patricia Silva Zanus Mauro Celso Diamante Marla Silvia Kluge Ricardo Alfredo Lima Giuseppina Pace Pereira 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):258-264
Plant Foods for Human Nutrition - Some biogenic amines (BAs) are used as quality markers in grape-derived products. The prolife of 9 BAs was determined in juices and wines elaborated from hybrid... 相似文献
656.
David Sewordor Gaikpa Silvia Koch Franz Joachim Fromme Dörthe Siekmann Tobias Würschum Thomas Miedaner 《Plant Breeding》2020,139(3):508-520
Rye is a multi-purpose cereal crop grown in Central and Eastern Europe as well as in Western Canada. Fusarium head blight (FHB) is one of the diseases that have a severe negative impact on rye, but knowledge about FHB resistance at the genomic level is totally missing in rye. The objective of this study was to elucidate the genetic architecture of FHB resistance in winter rye using genome-wide association (GWA) mapping complemented by genomic prediction (GP) in comparison with marker-assisted selection (MAS). Additionally, plant height and heading stage were analysed. A panel of 465 S1-inbred lines of winter rye was phenotyped in three environments (location–year combinations) for FHB resistance by inoculation with Fusarium culmorum and genotyped with a 15k SNP array. Significant genotypic variation and high heritabilities were found for FHB resistance, heading stage and plant height. FHB did not correlate with heading stage, but was moderately correlated with plant height (r = −.52, p < .001) caused by some susceptible short inbred lines. The GWA scan identified 15 QTL for FHB resistance that jointly explained 74% of the genotypic variance. In addition, we detected 11 QTL for heading stage and 8 QTL for plant height, explaining 26% and 14% of the genotypic variance, respectively. A genome-wide prediction approach resulted in 44% higher prediction abilities than marker-assisted selection for FHB resistance. In conclusion, genomic approaches appear promising to improve and accelerate breeding for complex traits in winter rye. 相似文献
657.
Silvia L. Toffolatti Giuliana Maddalena Demetrio Marcianò Alessandro Passera Fabio Quaglino 《Plant pathology》2020,69(9):1695-1707
Botrytis cinerea, the grey mould agent, is one of the most important pathogens of grapevine, due to the great yield losses caused and the economic costs related to disease control. Ground cover plants are assumed to have a role in the complex epidemiology of the pathogen, even if no information on the genetic variability of the strains is available. In this study, a molecular epidemiology approach, based on the comparative analysis of the nucleotide sequences of multiple genes (ITS1-ITS2, G3PDH, NEP1, NEP2, BC-hch, and sdhB), was used to evaluate whether B. cinerea isolated from herbaceous species contributes to grey mould diffusion on grapevines. From 330 samples collected in two vineyards in Lombardy, Italy, 63 B. cinerea strains were isolated from tissues of grapevine with symptoms (50 strains) and spontaneous ground cover plants (13 strains). Capsella bursa-pastoris, Cardamine impatiens, Lamium purpureum, and Crepis tectorum were identified as novel B. cinerea hosts. Sequence analysis and phylogeny showed that the same genotypes were present on both grapevines and herbaceous plants, with no fitness (estimated from growth and sporulation on potato dextrose agar) or pathogenicity (on grapevine leaves and berries, and tomato leaves) penalties. This confirms that ground cover plants can be a source of inoculum for B. cinerea on grapevine. Moreover, phylogenetic analysis of the BC-hch gene allowed the identification of two genetically distinct clusters, characterized by vegetative incompatibility and different distributions of the mating types, fitness, and pathogenicity. Therefore, B. cinerea seems to be composed of two diverging subpopulations that do not differ for host specialization. 相似文献
658.
659.
Effects of dietary mannan oligosaccharides in early weaning diets on growth,survival, fatty acid composition and gut morphology of gilthead sea bream (Sparus aurata,L.) larvae
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Kamil Mert Eryalçin Silvia Torrecillas Maria Jose Caballero Carmen Maria Hernandez‐Cruz John Sweetman Marisol Izquierdo 《Aquaculture Research》2017,48(9):5041-5052
Early weaning of marine fish larvae with dry diets delays gut maturation and reduces growth rates. In juvenile and adult forms of several marine fish species, inclusion of dietary mannan oligosaccharides (MOS) improves gut integrity and functionality, but the effects of MOS inclusion in gilthead sea bream (Sparus aurata, L.) larval diets have not been addressed yet. Thus, this study assesses the effects of dietary MOS inclusion on survival, growth performance, gut morphology, feed acceptance and quality of gilthead sea bream larvae. For that purpose, 16 days post‐hatched gilthead sea bream larvae were fed four graded levels of MOS (Biomos®, Alltech, Nicholasville, KY, USA) in weaning diets as follows: 0 g kg?1 MOS, 0.5 g kg?1 MOS, 1.5 g kg?1 MOS and 2 g kg?1MOS. Dietary MOS did not affect feed acceptance in gilthead sea bream larvae (P > 0.05). MOS supplementation was correlated in a dose‐dependent way with higher larval survival (P = 0.026). After 15 days of feeding, dietary MOS increased whole larvae (P < 0.01) arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid. Gilthead sea bream larvae fed 2 g kg?1 MOS presented higher gut occupation with goblet cells after feeding compared with larvae fed the other dietary treatments. Overall, the results suggest that inclusion of MOS in early weaning diets for gilthead sea bream improves essential fatty acid utilization and may promote growth and final survival. 相似文献
660.
Giovanni Bearzi Nino Pierantonio Silvia Bonizzoni Giuseppe Notarbartolo di Sciara Massimo Demma 《水产资源保护:海洋与淡水生态系统》2010,20(6):644-654
- 1 The view that whales are malicious monsters has been pervasive throughout history. Conversely, the idea that these animals experience suffering has emerged only recently. One way of investigating perceptual, as well as behavioural, shifts is assessing general public reactions to mortality events involving wild, rare and charismatic animals.
- 2 Here, the responses of 118 individuals to questions regarding the mass stranding of seven sperm whales (Physeter macrocephalus) along the Adriatic Sea coast of Italy in December 2009 are reported through interviews taken at the stranding site and in the direct proximity of the dead animals.
- 3 When asked why the whales were stranded, 44.1% of the respondents suggested anthropogenic causes and 21.2% non‐anthropogenic. The remaining 34.7% mentioned a generic ‘disorientation’ or stated they did not know. When asked how they felt about the whales, 68.6% expressed feelings of compassion or care towards the animals. Clearly non‐compassionate attitudes accounted for only 4.1% of the sample. Finally, 21.2% expressed feelings that were ambiguous in terms of being suggestive of compassionate or non‐compassionate attitudes, including 11.9% amazement, 4.2% deprecation and 5.1% powerlessness.
- 4 These results are in stark contrast with information obtained from accounts of similar events that have occurred in historical times, up until the first half of the 20th century. For centuries, responses to cetacean live strandings—typically including killing and harming of the animals—were either utilitarian or characterized by feelings including fear and a desire to ‘subjugate the beast’, with no apparent concern for their suffering and death.
- 5 It is concluded that attitudes towards whales—today strikingly revolving around sadness, compassion and a sense of loss—have changed dramatically over time, with a steep turnaround in the 1970/1980s. Full appreciation of the ongoing evolution in public perception can channel marine conservation efforts and assist in the design of response strategies to marine mammal strandings. Copyright © 2010 John Wiley & Sons, Ltd.