首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Safflower — production,processing and utilization   总被引:1,自引:0,他引:1  
Safflower, grown formerly for the red dye from its flowers, is now a source of oil and livestock feed. In California an average of 30,000 acres have been grown each year since 1950. It has been both a dryland and irrigated crop. The oil has had a ready market for the manufacture of alkyd resins and drying oils.  相似文献   

2.
United States annual production oi this formerly very important bast fiber has fallen from about 75,000 tons a century ago to about 2,000 tons today. Imports, too, have dropped. Other fibers, particularly abacá, have replaced it more and more.  相似文献   

3.
A corn-like cereal grass which among its 400 known varieties produces broomcorn, the principal material used in the manufacture of brooms, and important edible grains of Africa and Asia—durra, kafir, milo, shallu, kaoliang, feterita and hegari.  相似文献   

4.
The female cone-like inflorescences oi this vine are composed of scales covered with glandular hairs which produce, among other compounds, the bitter principle which has long been an indispensable ingredient in the brewing of beer. These largescale catkins have been used also in medicine because of their sedative and soporific properties, and as a tonic.  相似文献   

5.
Jute fibre is the world’s principal material in manufacturin? coarse textile for conversion into sackin? and canvas. It enters also into the production of upholstery, ru?s, carpets and roofin? fabrics. Secondary products are food from its tender shoots, medicines from its dried leaves, fuel and paper from its stems, and oil from its seeds.  相似文献   

6.
Although not the lightest known wood, balsa is the lightest commercial timber, and as such has found utilization in the manufacture of airplanes, life preservers, insulating equipment and packing crates. During recent war years Ecuador supplied 95 percent of world production but must now meet competition from wild and cultivated sources in Central America and Ceylon.  相似文献   

7.
Escherichia coli stores large amounts of highly pure product within inclusion bodies (IBs). To take advantage of this beneficial feature, after cell disintegration, the first step to optimal product recovery is efficient IB preparation. This step is also important in evaluating upstream optimization and process development, due to the potential impact of bioprocessing conditions on product quality and on the nanoscale properties of IBs. Proper IB preparation is often neglected, due to laboratory-scale methods requiring large amounts of materials and labor. Miniaturization and parallelization can accelerate analyses of individual processing steps and provide a deeper understanding of up- and downstream processing interdependencies. Consequently, reproducible, predictive microscale methods are in demand. In the present study, we complemented a recently established high-throughput cell disruption method with a microscale method for preparing purified IBs. This preparation provided results comparable to laboratory-scale IB processing, regarding impurity depletion, and product loss. Furthermore, with this method, we performed a “design of experiments” study to demonstrate the influence of fermentation conditions on the performance of subsequent downstream steps and product quality. We showed that this approach provided a 300-fold reduction in material consumption for each fermentation condition and a 24-fold reduction in processing time for 24 samples.  相似文献   

8.
Bacteroides polypragmatus, a mesophilic obligate anaerobe, was shown to simultaneously ferment glucose and cellobiose giving ethanol as a major metabolic end-product. A mixture of higher cellodextrins was also utilized. The bacterium produced a -glucosidase with a pI value of 4.2 and a molecular weight of approximately 100000 daltons. The enzyme was intracellular and functioned optimally at pH 7. The K m values obtained with p-nitrophenyl--d-glucoside and cellobiose as substrates were 0.73 mM and 100 mM, respectively. The enzyme was quite stable at elevated temperatures; in the presence of 10% glycerol (v/v), it had a half-life of 4 h at 55°C. It was also stable during long-term storage at either 4°C or-20°C, provided that 10% (v/v) glycerol was added to preparations maintained at-20°C.Abbreviations HPLC high-performance liquid chromatography - IEF isoelectric focusing - pNPG p-nitrophenyl--d-glucoside NRCC No. 25676  相似文献   

9.
Transglutaminase (EC 2.3.2.13) catalyses an acyl-transfer reaction in which the -carboxamide groups of peptide-bound glutaminyl residues are the acyl donors. The enzyme catalyses in vitro cross-linking in whey proteins, soya proteins, wheat proteins, beef myosin, casein and crude actomysin refined from mechanically deboned poultry meat. In recent years, on the basis of the enzyme's reaction to gelatinize various food proteins through the formation of cross-links, this enzyme has been used in attempts to improve the functional properties of foods. Up to now, commercial transglutaminase has been merely obtained from animal tissues. The complicated separation and purification procedure results in an extremely high price for the enzyme, which hampers a wide application in food processing. Recently studies on the production of transglutaminase by microorganisms have been started. The enzyme obtained from microbial fermentation has been applied in the treatment of food of different origins. Food treated with microbial transglutaminase appeared to have an improved flavour, appearance and texture. In addition, this enzyme can increase shelf-life and reduce allergenicity of certain foods. This paper gives an overview of the development of microbial transglutaminase production, including fermentation and down-stream processing, as well as examples of how to use this valuable enzyme in processing foods of meat, fish and plant origin.  相似文献   

10.
Arabic, tragacanth, ghatti, karaya and other commercially valuable gums are exudations of a variety of trees and shrubs in many parts of the world. Their hydrophilic and other properties render them useful in the adhesives, beverage, cosmetic, paint, papermaking, pharmaceutical, textile and other industries.  相似文献   

11.
This cementing substance between the cells of all plants is economically valuable as a jellifying, stabilizing, emulsifying and binding agent, and is extracted for those purposes principally from apple pomace and citrus peels.  相似文献   

12.
The residual failures of harmony between botanical and cultivated plant systematists is related to a review of their methodologies. Because some cultivated plant groups overlap the distinction, it is argued that special classification systems are not appropriate generally to cultivated plants. A fundamental reason for the difficulty is suggested and it is shown that this still allows, as a compromise solution, the adoption of the author's previously published flexible unified hierarchy of categories, which is figured and its relevance to the whole situation explained. Some misunderstandings between botanists and horticulturists are reviewed and explanations consistent with the previous discussion offered. These concern typification, whether cultivars require types or have synonyms and what should be done about the confusion of typical. The relationship between the Codes is clarified by an example and the matter of the gardener's species is discussed.Dedicated to the memory of JohnS. L. Gilmour.  相似文献   

13.
The aqueous extract of witch hazel twigs has long been an American household liniment, but only three concerns manufacture it today, producing over halt a million gallons annually. The more concentrated tannin-containing alcoholic extract from leaves and bark is compounded into styptic remedies.  相似文献   

14.
Accroides, Congo, damer, boea, elemi, kauri, mastic and other commercially valuable resins are exudations ot a variety of trees and shrubs in many parts of the world. Their industrial applications range from adhesives and incense through inks and oilcloth to textile sizing and wax compositions.  相似文献   

15.
16.
Cyclodextrins (CD) are cyclic α-1,4-glucans composed of glucose units, and they have multiple applications in food, pharmaceuticals, cosmetics, agriculture, chemicals, etc. CD are usually produced by cyclodextrin glycosyltransferase (CGTase) from starch. In the present study, a simultaneous conversion approach was developed to improve the yield of CD from starch by conjunction use of isoamylase with α-CGTase. The isoamylase of Thermobifida fusca was cloned and expressed in Escherichia coli BL21(DE3). The biochemical characterization of the enzyme showed that the optimum temperature and pH of the recombinant enzyme was 50 °C and 5.5, respectively, and it maintained 60 %, 85 % and 78 % relative activity at 30 °C, 40 °C and 60 °C, respectively. When the recombinant isoamylase and α-CGTase were used simultaneously to convert potato starch (15 %, w/v) into CD, the optimum conditions were found to be: 10 U of α-CGTase and 48 U of isoamylase per gram of substrate, with reaction temperature of 30 °C and pH 5.6. On the optimum condition, the total yield of CD reached 84.6 % (w/w) after 24 h, which was 31.2 % higher than transformation with α-CGTase alone. This is the first report of synchronous bioconversion of CD by both α-CGTase and isoamylase, and represents the highest efficiency of CD production reported so far.  相似文献   

17.
Several microalgae, such as species ofChlorella, Spirulina andDunaliella, are grown commercially and algal products such as -carotene and phycocyanin are available. The main focus of algal biotechnology continues to be on high value fine chemicals and on algae for use as aquaculture feeds. This paper provides the outline for a rational approach in evaluating which algae and which algal products are the most likely to be commercially viable. This approach involves some simple market analysis followed by economic modelling of the whole production process. It also permits an evaluation of which steps in the production process have the greatest effect on the final production cost of the alga or algal product, thus providing a guide as to what area the research and development effort should be directed to. An example of this approach is presented and compared with other models. The base model used here gives a production cost of microalgal biomass at about AS 14 to 15 kg–1, excluding the costs of further processing, packaging and marketing. The model also shows that some of the key factors in microalgal production are productivity, labor costs and harvesting costs. Given the existing technology, high value products such as carotenoids and algal biomass for aquaculture feeds have the greatest commercial potential in the short term.This paper was presented at the Symposium on Applied Phycology at the Fourth International Phycological Congress, Duke University.  相似文献   

18.
Pure cultures of H2/CO2- and formate-utilizing methanogens or mixed consortia of sewage sludge generated some formate from H2/CO2 at H2 partial pressure in the gas phase above 200 kPa. At decreasing H2 partial pressure the formate was taken up again and converted to methane. If methanogenesis was inhibited by bromoethanesulphonic acid (BESA) or a high redox potential (–180 to –200 mV), formate-utilizing methanogens produced high amounts of formate from H2/CO2. No formate was excreted by the species, which could only utilize H2/CO2 for methanogenesis. In contrast, H2 formation from formate was observed in cultures of Methanobacterium thermoformicicum and M. formicicum. Measurable amounts were, however, only formed if its immediate utilization for methane production was inhibited by BESA. In the light of the data on formate formation from H2/CO2 and its re-utilization by all formate-utilizing methanogens, the concept of interspecies formate transfer of Thiele and Zeikus should be reconsidered. In pure cultures of methanogens or complex ecosystems with excess H2, formate formation seemed to serve more as a means of disposal of surplus reducing power than for H2 transfer. Correspondence to: J. Winter  相似文献   

19.
Chitinases (E.C.3.2.1.14) are thought to play an important role in the defense of plants against fungal invasion. By screening a barley genomic library with a previously identified chitinase eDNA clone (clone 10), a genomic clone was isolated and characterized by DNA sequencing of the chitinase coding region and flanking sequences. This clone contains an open reading frame capable of coding for a 34 kD chitinase. Comparison of the amino acid sequence of the encoded protein with other barley chitinases suggests that the genomic clone encodes chitinase T, which has been characterized extensively by protein sequencing. Treatment of barley leaves and aleurone protoplasts with N-acetyl glucosamine oligomers which act as elicitors in other plants, did not lead to the elevation of the levels of the chitinases. However, infection of barley seedlings with the powdery mildew fungus, Erysiphe graminis, resulted in the induction of several isoforms of chitinase. The level and number of chitinase isozymes was correlated with the severity of infection. The infection-related chitinases found in barley leaves are different from those found in seeds.  相似文献   

20.
Raghavan  V.  Baruah  H. K. 《Economic botany》1958,12(4):315-345
Economic Botany - To the Indians, Malayans, or the Indonesians, betel-nut chewing is as familiar as chewing gum to the Americans. In India the use of arecanut and its cultivation constitute a...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号