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Fourteen benzohydrazides have been synthesized and evaluated for their in vitro antifungal activity against the phytopathogenic fungus Botrytis cinerea. The best antifungal activity was observed for the N',N'-dibenzylbenzohydrazides 3b-d and for the N-aminoisoindoline-derived benzohydrazide 5. A quantitative structure-activity relationship (QSAR) study has been developed using a topological substructural molecular design (TOPS-MODE) approach to interpret the antifungal activity of these synthetic compounds. The model described 98.3% of the experimental variance, with a standard deviation of 4.02. The influence of an ortho substituent on the conformation of the benzohydrazides was investigated by X-ray crystallography and supported by QSAR study. Several aspects of the structure-activity relationships are discussed in terms of the contribution of different bonds to the antifungal activity, thereby making the relationships between structure and biological activity more transparent.  相似文献   
3.
The removal of the cyanobacterial peptide toxin microcystin-LR at 4 and 37 degrees C by six commercial probiotic strains and Lactobacillus plantarum strains IS-10506 and IS-20506 isolated from dadih, Indonesian traditional fermented milk, was assessed in this study. The aim was to evaluate the main factors influencing the viability and metabolic activity of the probiotic strains, as well as their capacity to remove microcystin-LR. Both L. plantarum strains isolated from dadih, as well as Bifidobacterium lactis strains Bb12 and 420, were shown to be more resistant, and >85% remained viable in phosphate-buffered saline (PBS) solution for 48 h of incubation at either temperature, while the viability of the other four commercial bacteria decreased markedly over time. The effect of glucose on viability and removal of toxin was shown to be a strain-specific and strain-dependent property, but in general, the efficiency of microcystin-LR removal increased when glucose was added to the solution. A maximum removal of 95% was observed for L. plantarum strain IS-20506 (37 degrees C, 10 (11) colony-forming units mL(-1)) with 1-2% glucose supplementation and 75% in PBS alone.  相似文献   
4.
The intestinal mucosa-associated microbiota could play important biological roles due to its close proximity with the animal host, but knowledge on its composition is still limited. The aim of this study was to characterize the microbial communities tightly associated with different parts (rumen, duodenum and colon) of the gastrointestinal tract (GIT) of healthy lambs and calves by using both cultural, and fluorescent in situ hybridization-flow cytometry (FCM-FISH) techniques. Lactic acid bacteria genera were one of the predominant bacteria detected in lambs and calves by both methodologies, possibly constituting an index of their healthy status. The levels of Lactobacillus were significantly higher (p<0.05) in the rumen and duodenum of lambs, and in the rumen of calves. The levels of Bifidobacterium were significantly higher (p<0.05) in the colon of both animal species and the rumen of lambs. Significant differences (p<0.05) were found in counts of other microbial groups (yeast, Enterococcus, Propionibacterium, Bacteroides, Clostridium and Enterobacteriaceae) at diverse GI sections depending on the animal species. In general, microbial counts follow the same trends regardless the applied technique. The most remarkable differences were found in detection levels of Bacteroides and Clostridium, which tended to be significantly higher (p<0.05) when analysed by FCM-FISH. This technique also allowed the detection of quantitatively important bacteria (sulphate-reducing bacteria, Atopobium and Coriobacterium), which are difficult to cultivate in selective medium. Therefore, FCM-FISH has been proven to be a sensitive high throughput approach that provides additional information to that obtained by traditional culture techniques about the complexity of the GI ecosystem of these animal species.  相似文献   
5.
Summary

Nitrogenous fertilization effects on the protein concentration of flavedo of ‘Navelina’ oranges during ripening was studied in an experimental greenhouse, using cuttings grown in pots with inert sand and nutrient solution. Two types of nutrient solution were used: a nitrate solution (all nitrogen in nitrate form) and an ammoniacal-nitrate solution (40% nitrogen in ammonium form and 60% in nitrate form). The protein concentration of fresh flavedo of fruits irrigated with ammoniacal-nitrate solution was higher than that of fruits irrigated with nitrate solution. When the protein concentration of flavedo is high, the rind of fruits reach a yellow or orange-yellow colour earlier during development. In both types of nutrient solution, the quantity of nitrogen applied did not influence the total protein concentration of fresh flavedo nor the timing of fruit rind colour change from green to orange-yellow. After fruit set, the sooner the ammoniacal- nitrate nutrient solution was supplied, the sooner fruits reached an orange-yellow colour, and the higher was the total protein concentration of fresh flavedo, although there were no significant differences between the protein concentrations of flavedo of fruits from cuttings whose irrigation started with the ammoniacal-nitrate solution at different time. Results of this and a previous study suggest a relationship between the rind colour change and the protein concentration in the flavedo of fruit.  相似文献   
6.
Fishery by-products are rich in biologically active substances and the use of green and efficient extraction methods to recover these high-added-value compounds is of particular importance. In this study, head, skin and viscera of rainbow trout and sole were used as the target matrices and accelerated solvent extraction (ASE) (45–55 °C, 15 min, pH 5.2–6.8, 103.4 bars) and pulsed electric fields (PEF) (1–3 kV/cm, 123–300 kJ/kg, 15–24 h) were applied as extraction technologies. The results showed that ASE and PEF significantly increased the protein extract efficiency of the fish by-products (p < 0.05) by up to 80%. SDS-PAGE results showed that ASE and PEF treatments changed the molecular size distribution of the protein in the extracts, which was specifically expressed as the change in the area or number of bands between 5 and 250 kDa. The antioxidant capacity of the extracts was evaluated by oxygen radical absorbance capacity (ORAC) and total antioxidant capacity (ABTS) assays. The results showed that both ASE and PEF treatments significantly increased the antioxidant capacity of rainbow trout and sole skin and head extracts (p < 0.05). ASE and PEF extraction processes can be used as new technologies to extract high-added-value compounds from fish by-products.  相似文献   
7.
Abstract

The Mediterranean fruit fly, Ceratitis capitata, (Medfly) is considered a key pest of citrus fruit in many countries. Integrated pest management (IPM) approaches are frequently highly dependent on the use of insecticides. Oxitec’s self-limiting (prevents the insects’ offspring from surviving to adulthood) Medfly technology (OX3864A) offers an approach to manage Medfly outbreaks and may offer improved sustainability and economics for area-wide programmes. Netted cages were used to evaluate OX3864A deployed for the first time outdoors as a preventative treatment to suppress wild Medfly. Comparative assessments examined sexual competitiveness, the relative performance of OX3864A releases at both adult and pupal life-stages, and the ability of OX3864A to protect against fruit damage. OX3864A males are as competitive as wild males. Deployment of both adult and pupal life-stages of OX3864A effectively reduce Medfly abundance, resulting in elimination of the target pest populations. OX3864A deployment as adults also demonstrated the beneficial attribute of protecting fruit quality to preserve marketable yield. Data for adult and pupal deployment strategies are encouraging for self-limiting technologies targeting Medfly populations and support a broader evaluation of OX3864A Medfly or further improved self-liming Oxitec strains of Medfly in open settings.  相似文献   
8.
Widdrol (1) was tested against the necrotrophic plant pathogens Botrytis cinerea and Colletotrichum gloeosporioides. While 1 was found to be inactive against C. gloeosporioides, it showed a selective and effective control of B. cinerea, significantly inhibiting the mycelial growth of the fungus at concentrations of 100 ppm and above. In addition, the biotransformation of 1 by both fungi was studied. Incubation with C. gloeosporioides and B. cinerea afforded four and one biotransformation products (2-6), respectively. Biotransformation with C. gloeosporioides was highly regioselective, yielding for the most part oxidation products at C-10: 10-oxowiddrol (2), 10beta-hydroxywiddrol (3), 10alpha-hydroxywiddrol (4), and 14alpha-hydroxywiddrol (5). The structures of all products were determined on the basis of their spectroscopic data, including coupling constants, two-dimensional NMR analysis (heteronuclear multiple quantum coherence, heteronuclear multiple bond correlation, and nuclear Overhauser enhancement spectroscopy), and nuclear Overhauser effect. The biotransformation products were then tested against B. cinerea and found to be inactive. These results shed further light on the structural modifications, which may be necessary to develop selective fungal control agents against B. cinerea.  相似文献   
9.
Our aim was to identify elements useful in designing policies and programmes for conservation of farm animal genetic resources, taking as case study a group of European local cattle breeds. We first investigated the implications of differences among countries in the policies and programmes to be developed. Secondly, we analysed key elements common to countries, which may affect local breed viability. We used the herd size trend expected by the farmer in the near future as an indicator of breed viability. Fifteen breeds, for a total of 355 farms, were surveyed. To take into account the multiple factors influencing breeds’ demographic trends, the questionnaire included economical, technical and social aspects. Among the major differences across countries was the perception of the farmer on the value attributed to the local breed by society. Concerning the elements common to countries and their association to breed viability, the greater the collaboration among farmers and the stakeholders’ appreciation as perceived by the farmer, the greater the viability of the farm. An opposite trend was observed for the age of the farmer. Older farmers generally planned to soon cease farming or decrease herd size, whereas young farmers planned to increase the size of their herds. Implications of including these elements in conservation polices are discussed.  相似文献   
10.
Eleven beta-himachalene derivatives were tested, using the poisoning food technique, for their potential antifungal activity against the phytopathogen Botrytis cinerea. Compounds 1-11 displayed moderate activity, whereas the 6,7-diol derivative (12) produced an inhibition of 91% after 6 days. The microbial transformation of 12 was investigated and yielded four new compounds hydroxylated at positions C-5 (13), C-2 (14), C-4 (15), and C-12 (16). The structures were established on the basis of their spectroscopic data including two-dimensional NMR analysis (HMQC, HMBC, nOesy) and nOes. The results obtained from biotransformation experiments shed further light on the detoxification mechanism of the phytopathogenic fungus against this compound and give an indication of the structural modifications that may be necessary if substrates of this type are to be further developed as selective fungal control agents for B. cinerea.  相似文献   
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