Saturday, November 9, 2019
Poem Essay
India Williams Mrs. Holzmeister English 1102 February 8, 2010 The Theme of Love in Helen Farries ââ¬Å"Magic of Loveâ⬠and John Frederick Nims ââ¬Å"Love Poemâ⬠The word Love is a strange feeling that can be one of the most exciting things someone will ever experience. Itââ¬â¢s a feeling of warm, personal deep affection that one has for another person or thing. In Helen Farries poem ââ¬Å"Magic of Loveâ⬠she is very straightforward about how love makes someone feel ââ¬Å"It can comfort and bless/ it can bring happinessâ⬠(601). But in John Frederick Nimââ¬â¢s poem ââ¬Å"Love Poemâ⬠he uses metaphors to talk about love and you have to pay close attention to what he is saying. The theme of these two poems is love and the opposing views of the authorââ¬â¢s views of love. Helen Farries creates the image of love being magical. Love can make people feel good; make you feel bubbly and all warm inside, ââ¬Å"like the sun, it can warm your heartsâ⬠(601). She goes on to create an image that love is a gift, one that you can give and receive, ââ¬Å" Itââ¬â¢s a gift you can give every day that you live/ And when given, it comes back to you! â⬠(601). In John Frederick Nims poem he creates the picture of a clumsy person, ââ¬Å" My clumsiest dear, whose hands shipwreck vasesâ⬠(601), but people still see her beauty. Even though she is very clumsy he loves her anyway. In the first stanza of the poem you start to think that maybe this poem isnââ¬â¢t talking about love because of how he describes her as ââ¬Å" a bull in chinaâ⬠and ââ¬Å" a bur in linenâ⬠(601). Just when you think the poem isnââ¬â¢t about love, he changes directions and give her some praise, ââ¬Å"The refugee uncertain at the door/ You make at home; deftly you steady/ The drunk clambering on his undulant floorâ⬠(601). He loves her in spite of her flaws. In ââ¬Å"Magical Loveâ⬠, Farries uses informal diction. She uses plain, common, everyday kind of language that we all can understand. There are no riddles to try to decipher or to understand the meaning ââ¬Å"When love lights the way, there is joy in the dayâ⬠(601). In Nims ââ¬Å"Love Poemâ⬠he uses formal diction. With formal diction the poem comes across, as it should. He is seen as almost arrogant. He can do no wrong but his lovely lady has a lot of flaws but nonetheless he loves her in spite of them. He uses metaphors, ââ¬Å" In traffic of wit expertly maneuver/ And keep us, all devotion, at your kneesâ⬠(602) to get his point across. In both of these poems the common ground is Love. One-poem talks directly about how magical love makes you feel, and the other indirectly talks about love. They both say the same thing in two different ways. All the ups and down makes love between two people very beautiful. Works Cited Farries, Helen. ââ¬Å"Magic of Love. â⬠The Compact Bedford Introduction to Literature. Ed. Micheal Meyer. 8th ed. Boston: Bedford/ St. Martinââ¬â¢s, 2009. 601. Nims, John Frederick, ââ¬Å"Love Poem. â⬠The Compact Bedford Introduction to Literature. Ed. Micheal Meyer. 8th ed. Boston: Bedford/ St. Martinââ¬â¢s 2009. 601-602.
Thursday, November 7, 2019
Documentary analysis Essays
Documentary analysis Essays Documentary analysis Essay Documentary analysis Essay Food Inc. , a 2008 documentary film directed and produced by Robert Keener, exposes the secrets about how food is processed. Robert Keener is famous for exposing facts and controversies that are rarely discussed. He is also known for his authenticity and his desire to reveal the truth. Keener has received several awards for his films. Food Inc. Even influenced some food policy decisions. His documentary, Food Inc. , talks about the industrialization of the food system in America. The documentary is targeted towards the general public. The documentarys main focus or argument is that the agricultural business in America produces food that is both harmful to the environment and to the consumers while also being abusive to animals and workers. The documentary is informative. Its main objective is to inform the viewers about the secrets that are deliberately hidden from them. The documentary uses specific rhetorical appeals to support its objectives like, ethos. It provides statistics that show how much the food industry has changed over the years in America. It also interviews farmers that have firsthand knowledge of the food industry. The documentary also uses the pathos rhetorical appeal. The documentary shows scenes where animals are being treated inhumanely. For instance, dozens of cows were being kept in dirty pens. The cows could barely move and were covered in feces. The documentary also shows scenes where consumers suffer from the neglect of the companies that process the food. For example, a mother was talking about how her 2 year old son was killed because of E. Coli that he contracted from eating a contaminated hamburger. Moreover, there were also other children who were killed because of eating contaminated meat. The documentary also discussed how workers are being treated poorly. There are scenes showing illegal immigrant workers being arrested but the companies that hired them and brought them to America are not being questioned. This also stirs emotional response from the viewers. Another rhetorical appeal that was used is logos. It is logical that consumers will suffer the consequences of neglect. The documentary also provided a logical reason why companies do this. The reason is that it lessens the cost of production at the same mime, maximizes profits. Through the use of ethos, pathos and logos, the director was able to prove that the food industry produces food that is both harmful and abusive to the animals, consumers and workers. Food Inc. Is an eye opener. It shows the flaw of the food system in America. It unveils the truth that is deliberately hidden by the food processing companies to urge consumers to buy their products. Food is one of the most important commodities in the world. Consumers have the right to know where their food comes from and how it is processed.
Tuesday, November 5, 2019
Assessing the strengths and weaknesses of globalization
Assessing the strengths and weaknesses of globalization Globalization can be defined in a variety of ways since it is a very important term as it influences the global economies. It can be defined as the movement toward communications, financial, economic, and trade integration. Globalization entails opening out beyond nationalistic and local perspectives to a wider outlook of an interdependent and interconnected world through free transfer of goods, services, and capital over national frontiers. Globalization is a term that is frequently employed to place a trend in the direction of increased flow of ideas, money, goods, and services across national borders and the resultant consolidation of the global economy (Waters 2001, pg.36). Globalization is closely related to international trade which can be defined as the exchange of goods, services, and capital across territories or national border. The increase in the international trade enhances the continuance of globalization. If there were no international trade, then apparently nations w ould not get access to the variety of goods and services produced in different nations of the world (World Bank 2008, pg.56). It has been found that globalization does not involve unhindered labor movement, and as intimated by some economists, globalization may hurt fragile or smaller economies if practiced indiscriminately. Globalization is generally recognized as being goaded by a combination of technological, political, economic, biological and socio-cultural factors. From some other perspective, globalization can refer to the multinational circulation of languages, popular culture, or ideas by acculturation (Tomlinson 1999, pg. 123). This paper will provide an outstanding analysis of the weaknesses and strengths the term globalization. Strengths of globalization Supporters of globalization contend that globalization can possibly better the world economically by solving many problems which are deep-seated for example poverty and unemployment. According to the economic theory, inc reased globalization will lower the wage of unskilled labor in developed nations and raise the wage of unskilled labor within the developing nations as the two groups start to trade with each other. Globalization generates resources and encourages the transfer of ideas that can be utilized for both individual and community improvement. Among many other things, globalization makes rural economic diversification and agricultural productivity gains more achievable. Globalization also makes environmental stewardship, improved conditions of living, and food security more attainable. Due to globalization, the marginal can now get the opportunity to exhibit themselves in the world market (Bauman 1998, pg.121). Globalization encourages the industrialized nations to provide significant market places for exports of poor individuals within poor countries. The global agricultural and food companies can assist the third world countries incorporate required safety, and quality practices by gettin g access to markets in developed nations. Since globalization means delocalization of various enterprises within the word, many people can get access to many industries and in due course globalization promotes economic growth in the global world, brings about competition among companies, enables producers and retailers to reduce the prices of various commodities so that consumers can afford them and therefore increases the demand on the commodities. Because of the increased efficiency, the welfare is raised by offering more affordable goods and services such that the purchasing power is increased. Globalization reallocates capital and labor to more efficient and effective lines of production. Globalization helps poor countries by infusions of technology and foreign capital which enhances economic development. The economic development due to globalization brings modern ways of connecting people, from roads to electricity to telecommunications. The global companies offer training to e mployees and provide time, money and talent that helps them to address needs of the community, lifting communal and individual aspirations and providing ways for accomplishing them. Since globalization brings about spreading of prosperity, it enables various countries to possess conditions in which respect for human right and democracy can flourish (Appadurai 1996, pg.65).
Saturday, November 2, 2019
The Bretton Wood's institutions play a big role in intervening with Essay
The Bretton Wood's institutions play a big role in intervening with internal affairs of developing countries. How successful hav - Essay Example This is through regular monitoring and rigid policies especially on nations with weak institutions. On the other hand, foreign investment for poor nations should be limited to acquiring manageable loans and grants that do not collapse the economies. This will increase excellence both African and Asian nations in terms of economic prosperity. Development entails the well-being of a nation or individual in various forms. This may include economic, social or political development and the way it affects the citizens of such a country. Similarly, development may also encompass the gradual advancement or growth that leads to the progress in other sectors of the nation in terms of Gross Domestic Product (GDP) and exports among others. Other fundamental areas include education, health and governance in the context of the provision of services for the benefit of the citizenry. Therefore, the involvement of Bretton Woodââ¬â¢s institutions such as IMF, World Bank and IBRD ensure there is a f inancial regulation and fair dispensation of funds to sponsor developmental projects. Such institutions also participate in the regulation of the systems that oversee the monies dished to nations especially the third world countries (Szirmai 45). On that account, there are several ways, which education development, through funds acquired from Bretton Woodââ¬â¢s institutions has helped the advancement of nations. This is manifested in the increase of public schools and literacy levels where there participation of IMF and World Bank is high. In other words, education is now associated with sustainable development that permits people to gain skills, knowledge and skills. Other benefits include values and attitudes that are meant indicate a sustainable future where everyone thrives. Similarly, educational development has meant that matters of sustainable prosperity are translated in areas of learning and teaching for the purpose of students and society. In the same breadth, Bretton W oodââ¬â¢s institutions have given funds to support the reduction of poverty, biodiversity and sustainable consumption to education an enjoyable venture (Tiwari 167). This is manifested in a nations such India, Indonesia, Vietnam and Singapore where financial aid is boosting the education standards of most schools. In this case, the IMF and World Bank has dispensed funds in the ministries of education to facilitate standards of education. Therefore, this has translated to competencies of imagination, critical thinking and decision making skills in a mutual may for kids. This is also apparent in teachers and tutors who get motivation from governmental and non-governmental ventures. However, when it comes to economic development in terms of assistance from Bretton Woodââ¬â¢s institutions, there are interesting issues. This suggests that economic development entails concerted and sustained actions that are used by policymakers in the promotion of the living standards including eco nomic health. In the same breath, y in failed states mostly found in Africa such as Somalia and Democratic Republic of Congo, economic development refers to qualitative and quantitative alterations in the economy (Mbaku 134). Therefore, IMF and World Bank have not been successful in their development ventures because of several reasons. For example, issues such as bad governance policies, corruption and civil wars have hampered the efforts of Bretton
Thursday, October 31, 2019
Henry Essay Example | Topics and Well Written Essays - 750 words
Henry - Essay Example On approaching, he sees that the new owner of the hotel, which has been occupied up since World War II, is carrying boxes from the basement that contain personal items-clothing, photos, diaries and wedding memorabilia that belonged to Japanese families who had earlier been evacuated to internment camps during the war. Henry is taken back to his childhood by these small items, with a strong pull of memories though he tries as much as he can to resist it (Ford 308). This opening scene shows us to Henry present life, which gives the framework for the story in this Jamie Fordââ¬â¢s debut novel. This frame story suddenly leads the reader to the story line in 1942at Rainier Elementary school. Henry was just twelve years old and is under a scholarship. In this school, he is the only Chinese the rest are all whites. Henryââ¬â¢s father who is a Chinese and immensely proud of sending his son to a white school, do not at any time expect or allow anybody to be mistaken on Henryââ¬â¢s nationality. In the national consciousness, the events of Pearl Harbor are still fresh and Henryââ¬â¢s father is passionately against the Japanese and so he always sends Henry to school with a shirt with a button declaring ââ¬ËI am a Chineseââ¬â¢. This is the first moment of many depicts Henryââ¬â¢s already difficult relationship with his father (Ford 112). The tension between Henryââ¬â¢s American perspective and his fatherââ¬â¢s traditionalism Chi nese values is one of the major themes in the novel. He is struggling to live with his father. His life as a Chinese in an all-white school seems to be smooth, but the button provokes teasing by several of his class bullies, and his work-study job serving lunch becomes part of the day he dreaded the most. He arrives in the kitchen one day and finds a young Japanese lady, Keiko Okabe, also assigned for same shift. Being the only Japanese student in the school also, Keiko
Tuesday, October 29, 2019
Compare the powers of the federal government under the Articles of Essay
Compare the powers of the federal government under the Articles of Confederation to the powers of the federal government under the United States Constitution - Essay Example The US constitution gave powers to the federal government over issues of the national concern while the state government handled the issues of domestic concern. Regardless of that the Articles are not widely used, it is still a part of the United States constitution and still used from time to time to complement the United States Constitution. Although the Articles were the perfect constitution drafted, it still has some similarities with the U.S. constitution. First, both of them are federal U.S. documents. The central government is still the one in charge of the value of money and not the states. Both constitutions have defined term limits for the different offices in the government and they can borrow coins and set up a federal post office. The documents have a provision that can allow the government to establish an army and declare war on other countries and does not allow one state to enter into war by itself (Vile 34). However, as stated earlier, Article of Confederation had its flaws but the constitution came along and ratified the problems. As provided by the Articles, the federal government had very little power to make or enforce laws. Nine out of thirteen states needed in order to pass the laws. Only the states could have the privilege to create and operate courts. However, under the Constitution, the federal government is able to enforce and interpret the laws. Only fifty percent plus one vote and the signature from the president is required to pass laws. The executive branch headed by the president chooses the cabinet that checks on power of judiciary and legislature. The Article of Confederation allowed the federal government to borrow and spend funds, but it had not power to raise or level taxes of any kind (Vile 55). It also had no power to control trade agreements among the states or internationally. Each state entered into its
Sunday, October 27, 2019
Effects of Cor and US on Taxol Production of Taxus x Media
Effects of Cor and US on Taxol Production of Taxus x Media SUMMARY OF PROPOSED RESEARCH INCLUDING KEY GOALS For scientifically qualified assessors: Taxol is a natural diterpenoid alkaloid first isolated from the inner bark of pacific yew, Taxus brevifolia (Wani et al., 1971) and widely use in the pharmaceutical industry as the antitumor agents. However, low taxol content, high cost of extraction and the destruction of yew trees spark a major environmental controversy and cause a problem to fulfil its growing demand. The application of plant tissue culture technique has appeared as an eco-friendly method and feasible approach for commercial supply, but the production rate of this secondary metabolite are still very low. Only 10% of taxol secreted in the extracellular medium of T x media suspension cultures (Wickremesinhe and Arteca, 1993). These problems prompted a great effort to discover and identify the alternative means to enhance the mass production of taxol in plant cell cultures. In this study, elicitation using coronatine (Cor) and ultrasound (US) will be used for synthesis and transport of taxol. Cor is a toxin produced by Pseudomonas syringae and can act as a plant growth regulator and stimulates the defence mechanism in plants. Meanwhile, Low-intensity US is a physical or mechanical stimulus that can enhance the cellular transporter activity and trigger the pathway of defence-related secondary metabolites. It is hypothesized that the taxol accumulation in Taxus x media culture is higher than control (unelicited) and single treatment after treated with Cor and low- energy US. The experiment will use two-stage suspension culture and longitudinally young stem as the explant. The effect of these two elicitors on biomass production and taxol production will be analysed. At the end of this study, it is expected that the taxol production and cell growth will show positive result after elicited with Cor and low-energy US. This study will be a significant endeavour in enhance the release of taxol through elicitation approach. For lay readers: Secondary metabolites are chemicals produced by plants and do not have any physiological functions, but use as flavour, food colours, fragrances and pharmaceutical study. Taxus species are one of the medicinal plants that can produce natural anti-cancer agents known as taxol. However, over exploitation of natural sources of taxol from bark, stem, roots and needles put yew trees as an endangered species. Besides, the low yield and slow growth of yew trees limit its potential as a viable source of taxol. Thus, it is important to find alternative method to increase the taxol production in Taxus sp. The production of taxol from Taxus x media can be greatly enhanced through elicitation. Elicitation is a method to stimulate the gene expression of enzymes responsible for the synthesis of secondary metabolites. The substance used in stimulating the production of exuded compound is called elicitor. Elicitor is formed inside or outside of plant cells and imitate as a stress to activate the pla nt defence systems and cause qualitative and quantitative changes in the secondary metabolite content. Two elicitors that will be used in this study are Coronatine (Cor) and low-energy ultrasound (US). Plants use Cor to build defensive compounds and as growth regulators. US, on the other hand can stimulated the cell membrane permeabilization and encourage the release of taxol to culture medium. Plant cell cultures will be used to retrieve the secondary metabolite on demand by maintain the growth of plant cells in aseptic condition with appropriate supply of nutrients. It is expected that the accumulation of taxol treated with elicitors is higher than the untreated culture. This study will provide a good understanding about the effect of elicitors in activate the chemical defence system in plants and directly stimulate the production of taxol. RESEARCH Outcomes / Products What is the proposed outcome of your project: It is expected that all treatments will give significant increase of taxol accumulation when compared with control. Combination between Cor and US exposure will improve the extracellular and cell-associated taxol production. The expected taxol production from the treatment of both Cor and US is 20 to 50% higher than control. Elicitation of Taxus x media using Cor and US also will enhance the cell growth. The use of suspension culture will be one of the reasons that improve the accumulation of taxol and can be a good strategy for the continous production of taxol. Why is it important? Taxol is well known anti-cancer drug derived from natural source of Taxus species. However, direct extraction from yew trees has subjected them as an endangered species. On the other hand, the process of extraction and purification of taxol is also time consuming and not economically feasible. Thus, plant tissue culture is a promising approach to obtain this secondary metabolite. However, one of the main problems in increase the taxol production is instability in the synthesis of secondary metabolite. In order to maximize the yield of taxol, the combination of biotic and abiotic elicitor can be a good strategy. Besides, the elicitation approach is also more economical beneficial compare with other methods such as precursor feeding, phytohormone regulation and biotransformation. US is a simple but effective elicitor while Cor is expected has the similar biological activity as methyl jasmonate (MeJA), the most common elicitor used in stimulate secondary metabolites. The results from th is study can provide a fundamental understanding of the effects of US in combination with Cor on the production of secondary metabolite and plant cell culture. Understanding how Taxus x media cell culture react with these two elicitors can provide a a beneficial in link the growth rate with the production of taxol. DETAILS OF RESEARCH PROJECT Introduction and Background: Taxus species are medicinal plants and members of the Taxaceae family that can produce taxol, a chemotheraphy drug used widely in cancers treatment. FDA approval of taxol in 1992 and a series of success of taxol in clinical test for various cancers led to massive demand for this active substance. The increase of demand was expected since taxol also useful to combact non-canceorus disorders, such as polycystic kidney disease (Woo et al., 1994). However, it is difficult to perform large-scale culture because of the difficulty to gain this active compound from natural source. Three mature, century-old yew trees would produce only 1 g of taxol. It is estimated that about 10 tons of bark or felling of 3000 trees was needed to yield 1 kg of purified taxol to treat 500 cancer patients. Besides, the natural source of taxol from yew trees is only about 0.01% to 0.06% (Sung et al., 2005). All these concerns have prompted extensive efforts in find the method that can increase the mass productio n taxol. Taxus x media is choose for this study since it is good starting materials for the taxol production via biotechnological technique. Besides, the amount of taxol produce by this cultivar is the highest among other Taxus species (Table 1). The elicitation approach has been one of the most promising strategies in improve the mass production of taxol and other secondary metabolites in cell cultures (Roberts ND Shuler, 1997). The idea of using elicitor arise from the defence pathway utilize by plant in deal with environmental stress, pathogenic microorganisms, insects and higher herbivorous predators by stimulate the production of offensive chemicals like secondary metabolites. One of the most commonly studied and effective biotic elicitor is methyl jasmonate (MeJA). However, the report that Cor resemble the biological activity of the jasmonic acid gives an idea that the mode of action between these two compounds could be similar. The chemical structure of Cor is more stable than MeJA because of the rigid cis-orientation in its bi-cyclic skeleton. This lead to the higher levels of induction in the production of secondary metabolites by plant cells treated with Cor when compare with those treated with natural JA. Although Cor stimulated paclitaxel production with less efficiency than MeJA, it resulted in higher paclitaxel excretion to the liquid phases of culture medium. Besides that, there are not many reports about the influence of Cor on the production of secondary metabolite in plant cell suspension culture. Table 1: Content (wt %) of selected taxanes in different species of Taxus plants (Lin Lidong, 2003) The combination of biotic and abiotic elicitor had synergistic effects to taxol production in many reports. Thus, it is expected that the combine use of Cor with a physical stimulus like US might increase the yield of taxol in the Taxus culture. Generally, the abiotic elicitors use in experimental studies is chemical agents, heavy metals and biochemical agents like polysaccharides and organic acid. The use of US to biotechnology is relatively new and not many reports can be found on the effects of US in increase the useful secondary metabolites. This simple and effective elicitor can activate cells or enzymes and induced plant defence metabolism by ultrasonic waves. High intensity US waves can bring detrimental effect to cells, enzymes and other biological materials. Meanwhile, low intensity US waves can change the cellular metabolism, improve the mass transfer of reagents and enhance the release of intracellular products from cultured cells by increase the membrane permeability. The use of US will not disrupt the culture process and allow continuous use of cellââ¬â¢s biosynthetic capacity (Kilby and Hunter, 1990). US deserve an extensive research regarding its effects in plant secondary metabolite due to its wide application in biological field. The combination of Cor and US has great prospect and economic benefits in enhance the taxol production at low cost. Until now, there is no study or information about the effect of Cor and US and their combination on the Taxus species. Work which has led up to the project: The production of taxol using cell cultures were first reported by Christen et al., in 1989. Cell suspension cultures can emit secondary metabolites into growth medium. For instance, the production of resveratrol in the medium was higher than in the cell (Zamboni et al., 2009). Work by Kajani et al., in 2010 on Taxus baccata L cell culture showed that 74.9 % of total taxanes was exuded to growth medium (5. 584 mg/ L). Roberts et al., in 2003 reported that suspension culture of Taxus canadensis secreted more than 90% of the total taxol to the medium after treated with cell wall enzymes. Cell culture of Taxus chinensis emitted 90% of the total paclitaxel in medium with chitosan (Zhang et al., 2007). Komaraiah et al., in 2003 reported that up to 70% of the plumbagin in Plumbago rosea cell culture were released into the medium. Taxol accumulate at high level (1.5 mg/L) in the second phase of growth Previous research by J. Wu and L. Lin in 2003 on the application of US as a physical stimulus and MeJA in increase the mass production of taxol in Taxus chinensis becomes a fundamental reference for this study. Their study showed that the taxol yield was increased about 1.5- to 1.8-fold with 2 minutes US exposure once or twice during a 4 week culture period. Meanwhile, the total taxol after treated with MeJA increase about 5-fold. The percentage of extracellular taxol and cell-associated taxol also showed significant increase. The taxol production from combination between US and MeJA treatment was 20 to 50% higher than each of the treatment used alone. Another research by Wu and Lin in 2002 found that low energy US can play a role as abiotic elicitor to trigger the plant defence responses and induce the production of plant metabolite in cell cultures. Apart from that, US also can increase the cell membrane permeabilization to increase the efficiency of intracellular product release. In their previous study, they found that the combination of US stimulation and in situ solvent extraction in a Lithospermum erythrorhizan cell culture led to 2 to 3-fold increases in the yield of shikonin. Tamogami and Kodama reported in 2000 that Accumulation of flavonoid phytoalexins in rice occurred when treated with Cor. This shown that the effect of Cor on flavonoid production was greater than that of JA or its precursor, 12-oxo-phytodienoic acid (OPDA). Cor also gave positive result in the alkaloid production in Eschscholzia californica cell cultures (Haider et al., 2000). The previous work by also showed the greater increase in the accumulation of glyceollins, the phytoalexins of soybean (Glycine max. L.), in soybean cell suspension cultures after treated with Cor. Besides, the effect of Cor in induced the phytoalexin productin was greatly better when compared with JA and MeJA. (Fliegmann et al., 2003; Lauchli et al, 2002). Aims of the project: To study the biological and synergistic effects of Cor and US on the taxol production of Taxus x media cell culture. (d) Experimental design and methods to be used in investigating this problem: Cell culture establishment Approximately 1.0 cm long section of longitudinal young stem of Taxus x media will be wash with distilled water and soak in 70% (v/v) ethanol for 30 to 60 seconds. After that, the stem will be surface sterilized by immersion in 1.5% sodium hypochlorite with a few drops of Tween 20 for 20 to 30 minutes. After sterilization, the explants will be rinsed 3 times with sterile distilled water. Next, the longitudinally halved stem sections will be placed with the inner cut surface in contact with the solid Gamborgââ¬â¢s B5 media to induce calli. The media supplemented/ fortified with 3.0% sucrose (w/v), 0.8% agar (w/v), 1 mg/L 2,4-Dichlorophenoxyacetic acid (2,4-D) and 0.5 mg/L 6-Benzyladenine (BA), at pH 5.5. All of the cultures will be placed in darkness at 25oC for 25 days. To obtain a homogenous callus, several subcultures of calli will be done every 3 weeks. The snow, friable and massive callus will be used as the inoculums for cell suspension culture. Cor treatment The same media without agar will be used for cell suspension culture. About 10 g of fresh weight of callus will be used as the inoculums and inoculated into 300 mL conical flasks containing 100 mL liquid growth B5 medium and placed on orbital shakers (120 rpm) at 25oC in darkness. 1 uM Cor will be added to the shake-flask culture on day 7 post inoculation since the Taxus cell culture is expected to be in the middle of a rapid growth phase, which is usually a favourable time for elicitor treatment in most plant cell cultures. 3) US treatment An ultrasonic cleaning bath will be used to sonicate the cells in Erlenmeyer flasks from the shake-flask culture (Lin et al., 2001). The bath will had a fixed frequency of 38.5 KHz and variable power levels. The bath temperature wwill be maintained at 25à ±0.5oC. The culture will be sonicated at level 2 US power (corresponding to 13.7 mW/ cm3 in the culture) once (on day 5, 9, or 16) or twice (day 5 and day 9) for 2 min each time (total US energy of each exposure = power x period = 1.64 J/cm3). The US power and exposure period will be selected based on the study by Lin et al., (2001) and Lin and Wu in 2002. Determination of cell density The cells in the shake-flasks will be separated from the medium by filtration through a Whatman filter paper under vacuum. The wet cell mass will be rinsed thoroughly with deionized water and then dried at 50oC in an oven to constant weight. Taxol extraction and determination The taxol content in powdered dried cell and medium in the culture flasks will be extracted by methods previously described by Wu and Lin (2003). The dried cells will pulverized and suspended in 10 mL methanol, filtered and air-dried. After that, the cells will be re-dissolved in dichloromethane: water (1:1, v/v) followed by centrifugation at 5000 rpm. Dichloromethane phase will be collected, air-dried and re-dissolved in 100 à µL methanol (HPLC grade) and filtered passing through a 0.45 à µm syringe filter, before being injected to HPLC. The taxol content in the extract solution will be quantified by HPLC system, equipped with a C-18 column of 25 x 4.6 mm dimension. Taxol will be eluted with a linear gradient of acetonitrile and water (45: 55, v/v)/ at a flow rate of 1 mL/min with UV detection at 227 nm. Identification of taxol will be accomplished by comparison of retention times with authentic standard. Statistical analysis The results will be analyzed statistically by one-way ANOVA analysis and Duncan multiple range tests. The data will be presented as the mean value à ± standard deviation (SD) of three independent experiments.
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