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11.
Sebti I Chollet E Degraeve P Noel C Peyrol E 《Journal of agricultural and food chemistry》2007,55(3):693-699
Several properties of chitosan films associated or not with hydroxypropylmethylcellulose polymer (HPMC) and HPMC films incorporating or not nisin and/or milk fat were studied. Nisin addition at a level of 250 microg mL-1 and likewise chitosan at 1% (w/v) concentration were efficient for total inhibiting Aspergillus niger and Kocuria rhizophila food deterioration microorganisms. HPMC and chitosan films were transparent, whereas nisin and/or fat incorporation induced a 2-fold lightness parameter increase and, consequently, involved more white films. Measurements of tensile strength, as well as ultimate elongation, showed that chitosan and HPMC initial films were elastic and flexible. High thermal treatments and additive incorporation induced less elastic and more plastic films. Water vapor transmission as far as total water desorption rates suggested that chitosan films were slightly sensitive to water. Water transfer was decreased by <60% as compared with other biopolymer films. Regarding its hydrophobic property, the capacity of fat to improve film water barrier was very limited. 相似文献
12.
Pascal C Poncet-Legrand C Imberty A Gautier C Sarni-Manchado P Cheynier V Vernhet A 《Journal of agricultural and food chemistry》2007,55(12):4895-4901
Interactions between salivary proline-rich proteins and tannins are involved in astringency, which is one of the most important organoleptic sensations perceived when drinking wine or tea. This work aimed to study interactions between a recombinant human salivary proline-rich protein, IB-5, and a flavan-3-ol monomer, epigallocatechin gallate (EGCG). IB-5 presented the characteristics of natively unfolded proteins. Interactions were studied by dynamic light scattering, isothermal titration microcalorimetry, and circular dichroism. The interaction mechanism was dependent on protein concentration. At low concentrations, a three-stage mechanism was evidenced. Saturation of the interaction sites (first stage) was followed by protein aggregation into metastable colloids at higher EGCG/protein ratios (second stage). Further increasing this ratio led to haze formation (third stage). At low ratios, a disorder-to-order transition of IB-5 structure upon binding was evidenced. At high protein concentrations, direct bridging between proteins and EGCG was observed, resulting in significantly lower aggregation and turbidity thresholds. 相似文献
13.
Ayelo Pascal M. Mohamed Samira A. Chailleux Anas Yusuf Abdullahi A. Pirk Christian W. W. Deletre Emilie 《Journal of pest science》2022,95(2):633-652
Journal of Pest Science - Semiochemicals such as herbivore-induced plant volatiles (HIPVs) and host chemicals serve as communication signals for parasitoids searching for oviposition sites. The... 相似文献
14.
Pakull Birte Eusemann Pascal Wojacki Janine Ahnert Diana Liesebach Heike 《European Journal of Forest Research》2021,140(6):1543-1557
European Journal of Forest Research - In Germany, Douglas fir (Pseudotsuga menziesii Franco) is seen as a valuable species for future cultivation in times of climate change. Local seed production... 相似文献
15.
Bakary Traoré Nassim Moula Abdoulaye Toure Bara Ouologuem Pascal Leroy Nicolas Antoine-Moussiaux 《Tropical animal health and production》2014,46(7):1303-1312
Despite its importance in Mali’s economy, camel breeding in the country remains poorly documented, impeding effective policy-making in this regard. This study consisted in a 3-month survey and aimed at characterising camel breeding systems in Ansongo, in the region of Gao, Mali. It highlights the diversity of strategies adopted by breeders and their evolutions. Supplementary feeding and veterinary care were seldom practised. In zones close to the Niger River, cattle were substituted to camels. Transhumance routes also are modified but mobility keeps its vital role in the breeding system. Important differences within the study region in the classification of camel breeds have been reported that will influence the implementation of a collective action for animal genetic improvement. The improvement goals should take the actual management, including mobility and the mixed nature of the herds into account. 相似文献
16.
F. M. Rueda J. A. López F. J. Martínez S. Zamora P. Divanach & M. Kentouri 《Aquaculture Nutrition》1997,3(3):161-165
The total fat content and the fatty acids of total lipids (TL), phospholipids (PL) and triacylglycerols (TAG) were analysed in white muscle from wild and reared red porgy, Pagrus pagrus (L.). The fat percentage was higher in reared (3.03 ± 0.57%) (mean ± SE) than wild (0.65 ± 0.03%) fish. The fatty acid pattern of reared porgy TL reflected the diet's lipid. Wild red porgy showed higher levels of ω3 and ω6 polyunsaturated fatty acids (PUFA) than reared, but both the atherogenic index and the index of thrombogenicity were very low for both wild and reared red porgy. The lipid fractions showed that the PL were composed of very high levels of PUFA, especially 22:6ω3, and their composition seemed to be better regulated than the composition of TAG. TAG showed greater differences between wild and reared fish, presumably because they reflected the dietary content of lipids. PUFA were the principal component of wild red porgy TAG. 相似文献
17.
18.
N. Papandroulakis P. Divanach P. Anastasiadis M. Kentouri 《Aquaculture International》2001,9(3):205-216
The “pseudo green water” technology for sea bream(Sparus aurata) larval rearing was evaluated by analyzingresults of a 2-year study, performed in a pilot scale system. Thetechnology is characterized by the daily addition of phytoplankton in therearing tanks during the first month of rearing. Effects of egg origin,spawningseason and initial larval density on the larval rearing were investigated. Fishreared in “pseudo green water” systems for 60 days, presented highbiological performance in terms of survival (56 ± 16%), meanweight (62 ± 12 mg), total length (20 ± 1mm), conformity with wild standard (88 ± 9%), andfunctional swim bladder (93 ± 4%). The results present homogenitybetween the categories (origin of eggs, time of spawning, initial egg density)studied, proving the stability of the technology. 相似文献
19.
Johann D. Bell Natacha N. Agudo Pascal Blazer Dominique Pham 《Aquaculture (Amsterdam, Netherlands)》2007,273(4):509-519
We examined the potential for producing the large numbers of sandfish (Holothuria scabra) needed for restocking programmes by co-culturing juveniles with the shrimp Litopenaeus stylirostris in earthen ponds. Our experiments in hapas within shrimp ponds were designed to detect any deleterious effects of sandfish on shrimp, and vice versa. These experiments showed that a high stocking density of juvenile sandfish had no significant effects on growth and survival of shrimp. However, survival and growth of sandfish reared with shrimp for 3 weeks were significantly lower than for sandfish reared alone. Increased stocking density of shrimp also had a significant negative effect on survival and/or growth of sandfish. A grow-out trial of juvenile sandfish in 0.2-ha earthen ponds stocked with 20 shrimp post-larvae m− 2, and densities of sandfish between 0.8 and 1.6 individuals m− 2, confirmed that co-culture is not viable. All sandfish reared in co-culture were dead or moribund after a month. However, sandfish stocked alone into 0.2-ha earthen ponds survived well and grew to mean weights of ∼ 400 g within 12 months without addition of food. The grow-out trial demonstrated that there is potential for profitable pond farming of sandfish in monoculture. Further research is now needed to identify the optimal size of juveniles, stocking densities and pond management regimes. 相似文献
20.
Cultured red porgy Pagrus pagrus (L.) males (n=6) were sampled every 2 weeks for milt, in order to monitor changes in sperm quality parameters during a whole spawning period. On 11 January 2001, 60% of the fish were spermiating, increasing to 100% in mid‐February and dropping to 30% by mid‐April. Sperm density showed a slight increasing trend, with mean values ranging between 8.6 and 23.7×109 spermatozoa mL?1. Sperm motility percentage exhibited a significant improvement during the spawning season (analysis of variance (anova ) P=0.0001). The duration of forward motility for the major part of the monitoring period ranged between 2 and 4 min. Red porgy spermatozoa maintained their viability for many days after whole storage of milt at 4°C. During the monitoring period there were significant changes in the mean duration of sperm survival after cold storage, ranging from 5 to 12 days. The total volume of expressible milt was maximal on 28 March, increasing from a mean value of 1.7 mL to 5.3 mL kg?1. Milt production of captive‐reared red porgy does not appear to be limiting, when compared with the volume of expressible milt produced by other cultured marine fishes. 相似文献