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111.
Apple pomace as a substrate for bioethanol production is interesting due to its abundance and sustainable availability in varied states like Himachal Pradesh (H.P.), Jammu and Kashmir, Uttarakhand and Arunachal Pradesh, India. In the current study, apple pomace which is the main fruit industrial waste of H.P. was evaluated as feedstock for bioethanol production by the process of enzymatic saccharification using multiple carbohydrases. Microwave pretreatment of the apple pomace resulted in the efficient removal of lignin and crystalline structure of cellulose fibre. The enzymatic saccharification of the pretreated biomass was done by optimizing parameters for maximal saccharification leads to production of 27.50?mg/g of reduce, ng sugar. An enhanced ethanol yield of 44.46?g/l and fermentation efficiency of 58% by immobilized co-culture of Saccharomyces cerevisiae MTCC 3089 and Scheffersomyces stipitis NCIM 3498 under SHF as compared to fermentation performed with free yeast cells, i.e. 34.46?g/l of ethanol and 45% of fermentation efficiency.  相似文献   
112.
Polymorphism in the lengths of restriction fragments of the whole cpDNA molecule was studied in cultivated olive and in oleaster (wild olive) over the whole Mediterranean Basin. Seventy two olive cultivars, 89 very old trees cultivated locally, and 101 oleasters were scored for ten endonucleases. Moreover, maternal inheritance of cpDNA in olive was shown by analysing the progeny of a controlled cross between two parents which differed in their cpDNA haplotypes. In the whole species, three site- and three length-mutations were observed, corresponding to five distinct chlorotypes. The same chlorotype (I) was predominant in both oleasters and cultivated olive trees, confirming that these are closely related maternally. Three other chlorotypes (II, III and IV) were observed exclusively in oleaster material and were restricted either to isolated forest populations or to a few individuals growing in mixture with olive trees possessing the majority chlorotype. An additional chlorotype (V) was characterised by three mutations located in distinct parts the cpDNA molecule but which were never observed to occur separately. This chlorotype, more widely distributed than the other three, in both cultivated and wild olive, and occurring even in distant populations, was observed exclusively in male-sterile trees showing the same specific pollen anomaly. However, in the present study, no evidence was provided for a direct relationship between the occurrence of the cpDNA mutations and male sterility. It is suggested that the large geographic distribution of chlorotype V may be related to the high fruit production usually observed on male-sterile trees. These may be very attractive for birds which are fond of olive fruit and spread the stones efficiently. Probably for the same reason, people preserved male-sterile oleasters for long periods and, in several places, used male-sterile cultivars over large areas. Received: 25 November 1998 / Accepted: 19 December 1998  相似文献   
113.
In this study, physico-chemical modifications and community dynamics and functional role of the resident microbiota during composting of humid husk from a two-phase extraction system (TPOMW) were investigated. High mineralization and humification of carbon, low loss of nitrogen and complete degradation of polyphenols led to the waste biotransformation into a high-quality compost. Viable cell counts and denaturing gradient gel electrophoresis (DGGE) profiling of the 16S rRNA genes showed that the thermophilic phase was characterized by the strongest variations of cell number, the highest biodiversity and the most variable community profiles. The isolation of tannin-degrading bacteria (e.g. Lysinibacillus fusiformis, Kocuria palustris, Tetrathiobacter kashmirensis and Rhodococcus rhodochrous) suggested a role of this enzymatic activity during the process. Taken together, the results indicated that the composting process, particularly the thermophilic phase, was characterized by a rapid succession of specialized bacterial populations with key roles in the organic matter biotransformation.  相似文献   
114.
Olive pulp (OP) is a highly polluting semi-solid residue generated from the two-stage extraction processing of olives and is a major environmental issue in Southern Europe, where 80% of the world olive oil is produced. At present, OP is either discarded to the environment or combusted with low calorific value. In this work, utilization of OP as a potential substrate for production of bioethanol was studied. Enzymatic hydrolysis and subsequent glucose fermentation by baker's yeast were evaluated for OP from 10% to 30% dry matter (i.e., undiluted). Enzymatic hydrolysis resulted in an increase in glucose concentration by 75%, giving final glucose yields near 70%. Fermentation of undiluted OP hydrolysate (OPH) resulted in the maximum ethanol produced (11.2 g/L) with productivity of 2.1 g/L/h. Ethanol yields were similar for all tested OPH concentrations and were in the range of 0.49-0.51 g/g. Results showed that yeast could effectively ferment OPH even without nutrient addition, revealing the tolerance of yeast to OP toxicity. Because of low xylan (12.4%) and glucan (16%) content in OP, this specific type of OP is not a suitable material for producing only ethanol and thus, bioethanol production should be integrated with production of other value-added products.  相似文献   
115.
油橄榄孔雀斑病病原菌的鉴定   总被引:1,自引:0,他引:1  
对油橄榄孔雀斑病病原菌形态、人工培养,按种铡定和病菌来源进行了研究,经鉴定病原菌为环黑星霉[Spilocaca oleaginea (Cast.) Hugh]。分生孢子大多双胞,倒梨形至短倒棍棒形,大小19.6—21.2x8.9—9.8 m。分生孢子梗顶端有几个环痕。此病原菌由原产地带 进我国,为分布新记录。  相似文献   
116.
Olive stones are an agro-industrial by-product abundant in the Mediterranean area that is regarded as a potential lignocellulosic feedstock for sugar production. Statistical modeling of dilute-sulphuric acid hydrolysis of olive stones has been performed using a response surface methodology, with treatment temperature and process time as factors, to optimize the hydrolysis conditions aiming to attain maximum d-xylose extraction from hemicelluloses. Thus, solid yield and composition of solid and liquid phases were assessed by empirical modeling. The highest yield of d-xylose was found at a temperature of 195 °C for 5 min. Under these conditions, 89.7% of the total d-xylose was recovered from raw material. The resulting solids from optimal conditions were assayed as substrate for enzymatic hydrolysis, while fermentability of hemicellulosic hydrolysates was tested using the d-xylose-fermenting yeast Pachysolen tannophilus. Both bioprocesses were considerably influenced by enzyme loading and inoculum size. In the enzymatic hydrolysis step, about 56% of cellulose was converted into d-glucose by using an enzyme/solid ratio of 40 FPU g−1, while in the fermentation carried out with a cell concentration of 2 g L−1 a yield of 0.44 g xylitol/g d-xylose and a global volumetric productivity of 0.11 g L−1 h−1 were achieved.  相似文献   
117.
Olive fruits harvested at cherry and black stages of ripening were processed according the table olive black oxidising processing and sampled after the three main steps: storage in brine, lye treatment and thermal treatment (final product). The results show that the storage in brine contributed positively to the stabilisation of cell wall polysaccharides of olive pulp as the amounts of main polysaccharides practically were maintained in both stages of ripening. The lye treatment introduced degradation of cell walls due to the generalised loss of pectic and hemicellulosic polysaccharides and cellulose, caused by the breakage of ester and hydrogen bonds. On the other hand, the lye treatment introduced shifts in the solubilisation of polysaccharides rendering them more difficult to extract by alkali solutions and enabling their retention in the cellulosic residue, which should contribute positively to cell wall firmness. The thermal treatment introduced degradation of cellulose and increased the solubilisation of polysaccharides with a higher extent in the black olives. This work showed that the differences on the cell wall polysaccharides between stages of ripening are magnified after processing and allowed to conclude that the stage of ripening of olive fruits is determinant for obtaining a final product with adequate texture properties for table olive consumption.  相似文献   
118.
Abstract

Three specimens of the Olive Ridley Turtle (Lepidochelys olivacea) were collected in Guader (Gwatar) Bay in the Sea of Oman on 6 January, 1997. Two of them have been preserved for the Zoological Museum of Gorgan University. This is the first report of the Olive Ridley Turtle in Iranian coastal waters.  相似文献   
119.
We compared parasitic infection in a crop-raiding and a wild-foraging troop of olive baboons, Papio anubis, in Gashaka Gumti National Park, Nigeria, to quantify how crop raiding may have influenced primate-parasite interactions. We recovered gastrointestinal parasites from fecal samples from all adult individuals in both troops and processed them via formal-ether sedimentation. We compared parasitic species richness, prevalence, output, and load across troops. We recovered 9 parasite taxa. The wild-foraging troop had a significantly higher mean output than the crop-raiding troop for Physaloptera sp., Trichuris sp., and also a significantly higher total helminth load. The crop-raiding troop had a significantly higher mean output for the protozoan Balantidium coli and also showed a higher parasitic species richness, with 9 species recovered compared to the 7 recorded for the wild-foraging individuals. The changes in nutritional intake, behavior, and human proximity caused by crop raiding may have important epidemiological impacts on wild primate populations, and the nature of such impacts may vary across different taxa of parasites.  相似文献   
120.
Starting from solid wastes from two‐phase olive‐oil extraction, the pentacyclic triterpenes oleanolic acid and maslinic acid were isolated. These natural compounds were transformed into methyl olean‐12‐en‐28‐oate ( 5 ), which then was transformed into several seco‐C‐ring triterpene compounds by chemical and photolytic modifications. The triene seco‐products were fragmented through several oxidative procedures to produce, simultaneously, cis‐ and trans‐decalin derivatives, both potential synthons for bioactive compounds. The chemical behavior of the isolated fragments was investigated, and a suitable approach to several low‐molecular‐weight terpenes was performed. These are interesting processes for the value‐addition to solid waste from the olive‐oil industry.  相似文献   
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