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From: The supersonic descent could happen as early as Sunda. The weatheThe balloon will slowly drift to the edge of space at 120,000 feet (Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform. Below, the Earth bees the concrete bottom of a swimming pool that he wants to land on, but not too hard. Still, he39。如果我們一味逃避生活中的悲傷,悲傷只會(huì)變得更強(qiáng)烈更真實(shí) —— 悲傷原本只是稍縱即逝的情緒,我們卻固執(zhí)地耿耿于懷 By utilizing our breath we soften our experiences. If we dam them up, our lives will stagnate, but when we keep them flowing, we allow more newness and greater experiences to 。t start planning... Those years, those days of do, finally, like youth, will end in our life. 13 此刻,天空是陰暗的,空氣里有著剛下過(guò)雨之后的清新因子。想要的,不想要的,界限明確,好像沒(méi)有什么可以撼動(dòng)自己。 Junior high school, thought to have a crush on just means that the real growth, but over the past three years later, his writing of alumni in peace, suddenly found that isn39。s governing body, has also ordered an immediate investigation into the referee39。t appealed against the disciplinary action your employer has taken against you. However, if you win your case, the tribunal may reduce any pensation awarded to you as a result of your failure to appeal. Remember that in most cases you must make an application to an employment tribunal within three months of the date when the event you are plaining about happened. If your application is received after this time limit, the tribunal will not usually accept i. If you are worried about how the time limits apply to you If you are being represented by a solicitor at the tribunal, they may ask you to sign an agreement where you pay their fee out of your pensation if you win the case. This is known as a damagesbased agreement. In England and Wales, your solicitor can39。 microbiobogy 10 1992 , 58( 3) .1064— 1066; [3] 陳曉麗、呂振岳、黃東東等。但納他霉素產(chǎn)生菌株產(chǎn)量不高一直是 我國(guó)納他霉素自主生產(chǎn)的瓶頸,過(guò)低的單株產(chǎn)量會(huì)使生產(chǎn)成本過(guò)高而不利于工廠生產(chǎn)。L1) 圖 8 產(chǎn)黃青霉發(fā)酵液添加量對(duì)納他霉素產(chǎn)量的影響的影響 Fig 8 Effects of addition amount of Penicillium chrysogenum fermentation broth on the natamycin production of N5 strain 8 黑曲霉 發(fā)酵液添加量對(duì) N5 菌株納他霉素產(chǎn)量的影響 將培養(yǎng) 1d的黑曲霉發(fā)酵液處理后以不同添加量添加于培養(yǎng) 12h的納塔爾鏈霉菌 N5菌株發(fā)酵培養(yǎng)液中, 于 28℃、 200r/min 條件下繼續(xù)培養(yǎng) 84h,測(cè)定納他霉素產(chǎn)量結(jié)果如圖 8 所示。 6 圖 5 產(chǎn)黃青霉培養(yǎng)時(shí)間對(duì)納他霉素產(chǎn)量的影響 Fig 5 Effects of culture time of Penicillium chrysogenum on the natamycin production of N5 strain 黑曲霉培養(yǎng)時(shí)間對(duì) N5 菌株納他霉素產(chǎn)量的影響 將培養(yǎng)不同時(shí)間的 黑曲霉發(fā)酵液添加入 N5菌株發(fā)酵液中,培養(yǎng)后測(cè)定納他霉素產(chǎn)量,結(jié)果見圖 6。 01CK 0h 12h 24h 36h 48h 60h 72h納他霉素產(chǎn)量(g由圖 1可看出納他霉素濃度與 OD303值呈線 性相關(guān),且 R2= 線性較好。 真菌發(fā)酵時(shí)間對(duì)納他霉素產(chǎn)量的影響 分別在產(chǎn)黃青霉、黑曲霉、釀酒酵母培養(yǎng) 1d、 2d、 3d 時(shí)取樣,制備無(wú)菌發(fā)酵液。 真菌發(fā)酵液的制備 將產(chǎn)黃青霉、黑曲霉、釀酒酵母分別接種于裝有 100mL 發(fā)酵培養(yǎng)基的 250mL 三角瓶中,28℃、 150r/min 搖床培養(yǎng)適當(dāng)時(shí)間,用八層紗布過(guò)濾,再在 10000r/min 下離心 15min,取上清液進(jìn)行微孔濾膜過(guò)濾即可得到無(wú)菌的真菌發(fā)酵液。限 制我國(guó)自主生產(chǎn)納他霉素的主要問(wèn)題是菌株產(chǎn)量偏低,導(dǎo)致納他霉素的生產(chǎn)成本過(guò)高。該抗生素是 一種二十六元多烯大環(huán)內(nèi)酯類抗生素,主要由 納塔爾鏈霉菌( streptomyces natalensis)、褐黃孢鏈霉菌( streptomyces gilvosporeus)、恰塔努加鏈霉菌( streptomyces chattanoogensis)等菌發(fā)酵產(chǎn)生[2]。 安 徽 農(nóng) 業(yè) 大 學(xué) 畢 業(yè) 論 文(設(shè)計(jì)) 論文題目 真菌發(fā)酵液對(duì)納塔爾鏈霉菌納他霉素產(chǎn)量的影響 姓 名 學(xué) 號(hào) 院 系 _生命科學(xué)學(xué)院 _ 專 業(yè) 生物技 術(shù) ____ 指導(dǎo)教師 職 稱 講師 __ _ 中國(guó) 納他霉素是一種高效、廣譜的抗真菌劑,能有效抑制霉菌及酵母的生長(zhǎng),并能有效抑制絲狀真菌中黃曲霉素的形成,可廣泛應(yīng)用于食品保鮮及治療真菌引起的疾病 [3]。這已成為急需解決的問(wèn)題。 納他霉素產(chǎn)量的測(cè)定 稱取納他霉素標(biāo)準(zhǔn)樣品,溶于 5%冰乙酸的甲醇溶液中,使納他霉素濃度分別為 1mg/L、2mg/L、 3mg/L、 4mg/L、 5mg/L、 6mg/L、 7mg/L、 8mg/L,用紫外分光光度計(jì)測(cè)其在 303nm處的 OD 值,以納他霉素濃度為橫坐標(biāo), OD303 值為縱坐標(biāo),繪制標(biāo)準(zhǔn)曲線。將培養(yǎng)不同時(shí)間的真菌發(fā)酵液以 5%接種量加入培養(yǎng) 12h的納塔爾鏈霉菌 N5菌株發(fā)酵培養(yǎng)液中,每個(gè)處理重復(fù) 3 次,并以不添加真菌發(fā)酵液的處理為對(duì)照。因此可通過(guò)此標(biāo)準(zhǔn)曲線方程 x=( y— )/ 計(jì)算納他霉素產(chǎn)量。L1) 圖 3 黑曲霉發(fā)酵液添加時(shí)間對(duì)納他霉素產(chǎn)量的影響 Fig 3 Effects of addition time of fermentation broth of Aspergillus Niger on the natamycin production of N5 strain 5 釀酒酵母發(fā) 酵液加入時(shí)間對(duì) N5 菌株納他霉素產(chǎn)量的影響 釀酒酵母發(fā) 酵液加入時(shí)間對(duì) N5 菌株納他霉素產(chǎn)量的影響見圖 4。由圖 6可以看出當(dāng)在 N5菌株發(fā)酵液中添加培養(yǎng) 1d的黑曲霉發(fā)酵液時(shí),納他霉素產(chǎn)量最高,因此,黑曲霉的最佳培養(yǎng)時(shí)間確定為 1d。由圖可看出 5%的黑曲霉發(fā)酵液對(duì) N5 菌株納他霉素的積累效果最佳,因此,黑曲霉發(fā)酵液的最適添加量確定為 5%。本實(shí)驗(yàn)將產(chǎn)黃青霉、黑曲霉、釀酒酵母發(fā)酵液添加入納塔爾鏈霉菌 N5菌株發(fā)酵液中,研究這 3 種真菌培養(yǎng)時(shí)間、發(fā)酵液添加時(shí)間及添加量對(duì) N5 菌株納他霉素產(chǎn)量的影響,以促進(jìn)菌株納他霉素的合成。新型天然食品防腐劑納他霉素的研究進(jìn)展[ J]食品研究與開發(fā) .( 4): 23; [4] 盧國(guó)營(yíng)、張朝輝、洪偉杰,新型防腐劑納他霉素的研究進(jìn)展[ J]中國(guó)食品添加劑 2021( 3): 30— 32; [5] 魏寶東、孟寬軍、天然生物性食品防腐劑納他霉素的特性及應(yīng)用[ J],遼寧農(nóng)業(yè)科學(xué) 2021 ( 2): 24— 26; [6] 賀家亮、張敏、趙勝娟,納他霉素的研究現(xiàn)狀[ J]中國(guó)食品添加劑 2021( 3): 30— 32; [7] Martin J F DEMAIN AL control of antibiotic biosynthesis 1980( 02); [8] 葉輝、王兆慧、陳佩林等 微生物誘導(dǎo)子對(duì)卡諾氏菌屬 N05205 菌株的影響[ J],生物技術(shù), 2021 14( 6):57— 58; [9] 邊猛、田黎、張久明等,誘導(dǎo) 子對(duì)