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141.

Mexican landrace avocados are naturally distributed mainly in high areas of central Mexico, where they have been produced and consumed since pre-Hispanic times. However, trees of these species are being replaced by improved varieties with greater global demand, and many species have been lost due to the destruction of their natural habitats. Many people in Mexico like to consume the pulp and peel of these fruits and have done so since pre-Hispanic times. This is because the peel of Mexican landrace avocados, unlike the peel of Hass avocados, is very thin and flavorful. The peel color may be bluish-purple or dark reddish due to the presence of anthocyanins, which are compounds with antioxidant activity. The objective of this study was to assess the oil and anthocyanin contents and to evaluate the antioxidant activity in fruits of 11 accessions collected from producing-regions of Mexico. The oil content was 16.2 to 32.3 g 100 g?1 in pulp, and the main unsaturated fatty acids were oleic, linoleic and palmitoleic acids, depending on the accession. The anthocyanin contents in peels ranged from 0.64 to 47 mg g?1 fresh weight. The highest antioxidant activity was found in the peel (53.3–307.3 mmol g?1 fresh weight). The results confirm that the pulp and peel of dark-peel Mexican landrace avocados could be important nutraceuticals for humans.

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142.
为了抑制冠突散囊菌发酵绿茶液态饮料中儿茶素的降解,本研究采用植物乳杆菌和冠突散囊菌对绿茶液态饮料进行联合发酵,试验通过响应面法优化了联合发酵绿茶液态饮料工艺,并采用高效液相色谱(HPLC)法和顶空固相微萃取串联气质联用(HS-SPME/GS-MS)法分别检测了联合发酵绿茶液态饮料中儿茶素含量和香气成分。结果表明,在干茶添加量10βg·L-1、冠突散囊菌添加量10βmL·L-1的前提下,联合发酵绿茶液态饮料的最佳工艺条件为植物乳杆菌添加量20βmL·L-1、蔗糖添加量75βg·L-1、30℃下静置发酵3βd。在此工艺下联合发酵绿茶液态饮料中总儿茶素含量为1β419.94βμg·mL-1,与冠突散囊菌发酵绿茶液态饮料(848.72βμg·mL-1)相比,显著增加(P<0.05);且醇类化合物(30.27%)、醛类化合物(15.25%)、烃类化合物(11.35%)、酯类化合物(9.86%)和酮类化合物(9.01%)含量与未发酵绿茶液态饮料相比均显著增加(P<0.05)。  相似文献   
143.
144.
Little is known about the impact of direct sowing under vegetation cover on the production and quality of New Rice for Africa(NERICA) on poor oxisol. In this study, two NERICA varieties(NERICA 3 and NERICA 8) were grown under tropical oxisol soil with very low nutrient contents. Four cultivation systems were used in completely randomized block design, including plowing(control), unplowed soil with dead vegetation cover(DVC), unplowed soil with live vegetation cover(LVC) and unplowed soil with mixed vegetation cover(MVC). DVC significantly improved the exponential growth of NERICAs. NERICA 3 was the more productive(2.16–3.05 t/hm~2) compared with NERICA 8(0.71–1.21 t/hm~2). Cultivation systems improved the nutritional quality of NERICAs. The total protein content of NERICA 3 under DVC and MVC was 84.8% and 75.0% higher than control, respectively. The total soluble carbohydrate contents of NERICA 8 under LVC and MVC was 73.2% and 57.3% higher than control, respectively. These results suggested that conservative approach like direct sowing on unplowed soil with vegetation cover systems can improve the nutritional quality of rainfed NERICAs and their sustainable production under poor oxisol soil in sub-Saharan Africa.  相似文献   
145.
The effect of three smoking durations (60, 90, and 120 min) and two smoking temperatures (60°C and 70°C) on proximate composition and quality of brackish cultured milkfish steaks of 3 cm size was studied. No significant difference was observed in the sensory properties across all the samples, except in the overall acceptability of sample smoked at 60°C for 60 min. There was significant difference in the values obtained for the textures of all the samples. The L*a*b* values showed a significant difference in the raw and smoked samples. The moisture content showed significant difference in all six samples. Naphthalene, fluorine, and anthracene were detected in the raw sample and in all the smoked samples with significant difference, except for naphthalene. The effect of smoking on the sensory properties and the moisture content of a smoked fish sample are dependent on the smoking time and temperature. Polycyclic aromatic hydrocarbon (PAH) concentration in smoked fish can be a factor, based on both water pollution and the smoking procedure. Benzo-a-pyrene and PAH4, which are acceptable indicators of total PAH presence in smoked foods, were not detected in all the smoked samples, thereby indicating the products to be safe for consumption.  相似文献   
146.
Panagrellus redivivus is a nematode with a high protein content and low‐cost production. It is successfully used in the larviculture of shrimp, however, it has not yet been evaluated as feed for Betta splendens larvae. Thus, the objective of this study was to evaluate P. redivivus as feed for betta larvae maintained at different depths of water. The experiment was based on a completely randomized 3 × 2 factorial design, represented by two feed types and one alternating feeding regime plus two water depths (2.5 and 5.0 cm). The Artemia feed promoted the highest weight gain, followed by the alternating feeding regime. The single use of the nematode as live feed produced the poorest weight gain. The water depth and the feeding method influenced the specific growth rate (SGR). At a depth of 2.5 cm, the alternating feeding promoted similar SGR compared to fish fed with Artemia only. Furthermore, at the greater water depth an improvement in SGR was observed in fish fed Artemia only, but the similarity to alternating feeding regime remains. Thus, the inclusion of nematode is an appropriate and lower cost feed strategy for the betta larviculture independent of water depths.  相似文献   
147.
Shea (Vitellaria paradoxa) butter is an important internationally recognised economic commodity because of its food and medicinal potentials. However, access to finance for small-scale forest enterprises such as shea butter production and marketing remains a fundamental problem, which affects the growth and performance of these enterprises. This study, therefore, assessed the financing schemes and delivery mechanisms available for the production and marketing of the product in Tamale, Northern Region of Ghana. It also identified the financial structures available to shea butter producers, including constraints of the financial delivery mechanisms. Using a social survey, the study purposively selected and interviewed 83 women who engaged in shea butter processing. Of these, 86% were full-time processors of shea butter and 14% were involved in other businesses, such as petty trading, groundnut and rice processing. The study revealed low patronage of financial services as only 18% of the respondents took loans. A high proportion (82%) of the respondents were under contract financing with companies that purchased the shea butter. This financing arrangement made it difficult for the women to expand their activities as they usually were unable to negotiate and receive competitive prices for their shea butter. Non-governmental organisations and some financial organisations were involved in providing technical support services to the producers. However, there was an absence of continuous support services in credit management. The high illiteracy rate (97%) of shea butter producers made it challenging for the women to access formal training programmes to make them aware of opportunities that exist for financing their business. There is the need for targeted collaboration among stakeholders to improve existing financing schemes. In the long term, there should be policies to standardise the activities of the shea butter industry to improve access to credit, which could lead to the sustainable growth of these enterprises.  相似文献   
148.
The purpose was to investigate the feeding value of fibrous cocoa pod husk (CPH) either fermented with Pleurotus ostreatus or supplemented with fibre-degrading multi-enzymes (Viscozyme®L?+?Pectinex®5XL) before inclusion in diets for 3-week-old finishing broilers. Growth performance and carcass yield of broilers fed diets containing 100, 200 or 300 g kg?1 of the P. ostreatus-fermented CPH or 100, 200 or 300 g kg?1 of the enzyme-supplemented CPH as well as a normal broiler finisher diet (control), were investigated in a 35-day feeding trial setup as a completely randomised design, with the seven treatments replicated three times. There were significant differences (P?P. ostreatus-fermented dried CPH up to a level of 200 g kg?1 and enzyme-supplemented dried CPH up to a level of 100 g kg?1 could be included in broiler finisher diets without any deleterious effects.  相似文献   
149.
The occurrence of African swine fever (ASF) DNA in slaughtered pigs in the major pig producing areas of Plateau state over a 2-year period was investigated. Three hundred fifty-nine pig tissue samples from five local government councils (LGCs) were analyzed by clinical signs (C/S), postmortem (PM) lesions and polymerase chain reaction (PCR). The results of diagnosis made by C/S and PM were compared to results obtained by PCR. Out of the 359 abattoir samples, 13 (3.62%) were positive by examination of C/S and PM lesions while 346 (96.38%) were negative. Jos-north LGC had the highest occurrence of PCR positive samples (31 samples); Panyam in Mangu LGC had no positive result. PCR analysis identified 53 positive samples (14.76%); more than 40 were identified on the field. Of the samples, 306 were PCR negative, thus giving a true ASF status of pigs in Plateau state. Analysis of the results, variables involved in the ASF spread and predictable effects of such findings in the pig industry in Plateau state and Nigeria as a whole is discussed.  相似文献   
150.
Skin blemishes of potato (Solanum tuberosum L.) tubers can cause severe economical losses to production. Some blemishes are due to known pathogens and others whose causes are unknown are called atypical blemishes. The present work aims at determining the origin of superficial atypical blemishes on a set of 204 tubers coming from 12 different French regions producing potato. The diversity of fungi and Streptomyces bacteria associated with blemishes was investigated by systematic isolation followed by identification by sequencing the internal transcribed spacer of the ribosomal DNA for fungi and by sequencing the 16S ribosomal DNA for bacteria. We found a high microbial diversity represented by 349 fungal isolates belonging to at least 47 different species and 21 bacterial strains of Streptomyces sp. The most represented fungi belonged to the genera Fusarium, Rhizoctonia, Alternaria, Penicillium, and Clonostachys. The pathogenicity of representative isolates was assessed in three bioassays; two bioassays based on single inoculations in previously sterilized potting mixture, and one bioassay based on both single and double inoculations under hydroponic conditions. We fulfilled the Koch’s postulates for Rhizoctonia solani AG 3 producing sclerotia. For other fungal and bacterial strains, our results did not show any causality or relationship between a single isolate or a complex and the occurrence of the blemishes. Moreover, the observation of irregular polygonal sunken corky lesions (polygonal lesions)—the most frequent atypical blemish—on non-inoculated tubers, suggested that the atypical blemishes could as well be a reaction of the plant to stressful environmental conditions.  相似文献   
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