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1、<p>  β-環(huán)糊精包合皮革防霉劑TCMTB的研究</p><p>  摘要:本文通過單因素實(shí)驗(yàn)與正交實(shí)驗(yàn)研究了用β-環(huán)糊精包合皮革防霉劑2-(硫氰基甲基硫代)苯并噻唑(TCMTB)的工藝。當(dāng)β-環(huán)糊精投入量為4.00克時(shí),通過改變TCMTB的加入量、包合時(shí)間、包合溫度,得到作為皮革緩釋長效防霉劑的最佳包合條件: TCMTB加入量為1.00克、包合時(shí)間為2小時(shí)、包合溫度為55℃,此條件下可獲得較高的包

2、合率產(chǎn)物,并對產(chǎn)物進(jìn)行了表征。應(yīng)用實(shí)驗(yàn)表明,防霉劑包合物的防霉性能優(yōu)良,且防霉時(shí)間比原藥明顯延長。</p><p>  關(guān)鍵詞:β-環(huán)糊精;2-(硫氰基甲基硫代)苯并噻唑;包合物;皮革;防霉劑</p><p>  Study on the antifungal agent of leather about β-cyclodextrin inclusion technology for TC

3、MTB</p><p>  Abstract: This paper takes a research on β-cyclodextrin inclusion technology for 2-(benzothiazolylthio)methyl ester through single factor experiment and orthogonal experiment. When the adding am

4、ount of β-cyclodextrin is 4.0000g, by changing the adding amount of TCMTB, inclusion time and inclusion temperature, we got the optimal conditions about the slow-release antifungal agent of leather as follows: the adding

5、 amount of TCMTB was 1.0000g, inclusion time was 2 h and inclusion temperature was 55℃</p><p>  Key words: β-cyclodextrin; 2-(benzothiazolylthio)methyl ester; Inclusion complex; Leather; Antifungal agent<

6、/p><p>  我國是皮革生產(chǎn)大國,據(jù)2005年統(tǒng)計(jì),皮革工業(yè)每年可為國家出口創(chuàng)匯達(dá)120多億美元。然而在制革生產(chǎn)中使用的原料皮富含蛋白質(zhì),脂肪等營養(yǎng)物質(zhì),具備微生物的生長條件,因而在保存過程中易發(fā)生霉變。因此需要進(jìn)行防霉處理。皮革上常用的防霉劑如五氯酚鈉、乙萘酚、對硝基苯酚等,因毒性太大而逐漸被淘汰和禁用。目前在國外,以2-(硫氰基甲基硫代)苯并噻唑(TCMTB)為有效成分的皮革防霉劑被廣泛使用[1],它與酚類物

7、質(zhì)相比,TCMTB防霉性能極佳,且用量少,是一種高效、廣譜、低毒、性價(jià)比高的防霉劑[2]。但如果直接使用,則藥效散發(fā)快,持續(xù)時(shí)間短,產(chǎn)生局部毒性大。環(huán)糊精是一種中空的桶狀化合物[3],外表面親水而內(nèi)表面疏水,這種憎水性內(nèi)腔可與很多油溶性物質(zhì)結(jié)合成復(fù)合物,增大油溶性物質(zhì)在水中的溶解性,形成具有緩釋作用的微囊,它已在醫(yī)藥、食品、農(nóng)藥、化肥的緩釋上得到較好的應(yīng)用[4][5][6],但是可用于皮革的緩釋型防霉劑很少見有報(bào)到。本文研究利用β-環(huán)糊

8、精對藥品的優(yōu)良包合與緩釋作用,對皮革防霉劑TCMTB進(jìn)行包合,研制使用方便、安全,可用于皮革的緩釋型防霉劑。</p><p><b>  1 實(shí)驗(yàn)</b></p><p>  1.1主要儀器與試劑</p><p>  主要儀器:JJ-1型定時(shí)電動(dòng)攪拌器,金壇市華峰儀器有限公司;真空旋轉(zhuǎn)蒸發(fā)儀SHZ-C,鞏儀市英峪予華儀器廠;超凈工作臺YJ-87

9、5A,蘇州三興凈化科技有限公司;電熱恒溫培養(yǎng)箱DHP350,武漢瑞華儀器設(shè)備有限責(zé)任公司。</p><p>  主要試劑:β-環(huán)糊精(β-CD),陜西禮泉化工有限實(shí)業(yè)公司;2-(硫氰基甲基硫代)苯并噻唑(TCMTB),江蘇宏陽化工有限公司。 </p><p><b>  1.2包合率的測定</b></p><p>  在萬分之一的賽多利斯分析天

10、平上準(zhǔn)確稱取上述一定質(zhì)量的β-環(huán)糊精包合物,加50mL二氯甲烷溶解,放入超聲波清洗器冷凝回流震蕩30min,靜置冷卻,抽濾,將所得濾液放入旋轉(zhuǎn)蒸發(fā)儀中蒸出二氯甲烷,稱出剩下的TCMTB重量,即為包合物中所包合的TCMTB的重量。</p><p>  1.3 TCMTB包合物制備方法</p><p>  將去離子水按實(shí)驗(yàn)設(shè)定條件加熱至實(shí)驗(yàn)溫度,再加入4克β-環(huán)糊精制成飽和溶液,用盡可能少的二

11、氯甲烷溶解一定量的TCMTB,緩慢滴加到β-環(huán)糊精飽和溶液中,攪拌反應(yīng)至實(shí)驗(yàn)時(shí)間,趁熱取出,放置至室溫,在冰箱3~5℃下冷藏24h,抽濾,沉淀物用少量去離子水洗滌,再用二氯甲烷淋洗兩次,于40℃真空干燥得淡黃色粉末狀包合物。</p><p>  1.4單因素影響實(shí)驗(yàn)</p><p>  1.4.1 不同TCMTB投入量對包合率的影響</p><p>  固定β-環(huán)糊

12、精加入量為4.00g,反應(yīng)溫度為50℃,反應(yīng)時(shí)間為2h,分別考察TCMTB加入量為0.60g、0.80g、1.00g、1.20g、1.40g、1.60g、1.80g時(shí)得到包合物的包合率,結(jié)果見圖1。</p><p>  1.4.2 不同反應(yīng)時(shí)間對包合率的影響</p><p>  固定β-環(huán)糊精加入量為4.00g, TCMTB加入量為1.00g,反應(yīng)溫度為50℃,分別考察反應(yīng)時(shí)間為0.5h、

13、1.0h、1.5h、2.0h、2.5h、3.0h、3.5h時(shí)得到包合物的包合率,結(jié)果見圖2。</p><p>  1.4.3不同溫度對包合率的影響</p><p>  固定β-環(huán)糊精加入量為4.00g, TCMTB加入量為1.00g,反應(yīng)時(shí)間為2h,分別考察反應(yīng)溫度為40℃、45℃、50℃、55℃、60℃、65℃、70℃時(shí)得到包合物的包合率,結(jié)果見圖3。</p><p&

14、gt;  1.5 正交實(shí)驗(yàn)設(shè)計(jì)</p><p>  依據(jù)單因素實(shí)驗(yàn)得出的初步實(shí)驗(yàn)結(jié)果,考察TCMTB加入量、反應(yīng)時(shí)間、反應(yīng)溫度3個(gè)因素對包合率的影響,各取3個(gè)水平設(shè)計(jì)L9(34)正交實(shí)驗(yàn),見表1.</p><p><b>  1.6 應(yīng)用實(shí)驗(yàn)</b></p><p>  由于皮革上霉菌的種類,隨皮革種類和環(huán)境的不同而有所不同,故本防霉效果實(shí)驗(yàn)選

15、用的測試菌種為皮革行業(yè)較常出現(xiàn)的黑曲霉、黃曲霉、青霉、根霉、毛霉5種霉菌為代表,用無菌移液管移取5mL上述五種霉菌的孢子懸浮液于錐形瓶中,塞上棉塞,在超聲波清洗機(jī)中震蕩10min,使霉菌孢子充分分散,然后放入冰箱中保存。采用平板菌落計(jì)數(shù)法進(jìn)行計(jì)數(shù),使1mL菌液中含霉菌孢子數(shù)為2.0×106個(gè)。將防霉劑原藥和包合物分別與幾種表面活性劑及溶劑混合均勻,加水配成含TCMTB都為0.3%的乳液。將經(jīng)防霉劑處理后的皮片(包括空白對照),

16、每個(gè)樣品做兩組平行樣,噴灑上述供試菌孢子懸浮液,然后懸掛在恒溫恒濕箱中,每四天觀察其霉變情況,由皮片表面長霉程度判斷防霉劑防霉性能的高低[9][10]。評價(jià)標(biāo)準(zhǔn)及防霉結(jié)果分別見表3和表4。</p><p><b>  表1 因素水平表</b></p><p><b>  因素</b></p><p><b>  

17、水平 </b></p><p>  TCMTB加入量/g 包合時(shí)間/h 包合溫度/℃</p><p>  A B C</p><p>  1 0.80 1.5 50</p><p>  2 1.00

18、 2 55</p><p>  3 1.20 2.5 60</p><p><b>  2 結(jié)果與討論</b></p><p>  2.1單因素影響實(shí)驗(yàn)分析</p><p>  環(huán)糊精可以包接油性客體物質(zhì)的原因是:在水溶液中,環(huán)糊精親脂

19、腔體中的水分子形成氫鍵的傾向得不到滿足,因而比溶液中的水分子具有更高的熱焓。所以,親脂性藥物整個(gè)分子能通過置換環(huán)糊精腔體內(nèi)的水分子來降低體系能量,這是形成包合物的原因。因此環(huán)糊精可以在水溶液中選擇性地與有機(jī)小分子結(jié)合,借范德華力、氫鍵、偶極互相作用而形成具有不同穩(wěn)定性的包合物。結(jié)合包合原理,為了提高反應(yīng)活性,提高結(jié)合常數(shù),使包合過程向正方向進(jìn)行,需找出合適的反應(yīng)條件,選擇了TCMTB投入量、包合時(shí)間、包合溫度這3種主要影響因素進(jìn)行討論。

20、</p><p>  2.1.1 TCMTB加入量的影響分析</p><p>  TCMTB的用量影響到所得產(chǎn)品的包合率和成本。因?yàn)棣?CD的空腔最大容納TCMTB有一飽和量。TCMTB加入量的影響如圖1所示,當(dāng)TCMTB加入量從0.60g到1.00g時(shí),隨著TCMTB投入量的增加,包合率基本保持不變,都在70%以上,此后,再增加TCMTB投入量,包合率不斷減少。這是由于提高TCMTB的投

21、入量,雖然可以使包合物中TCMTB的絕對量稍有提高,但同時(shí)有大量的藥物游離在外,所以TCMTB投入量為1.0000g為最佳。</p><p>  圖1 TCMTB加入量對包合率的影響</p><p>  2.1.2 包合時(shí)間的影響分析</p><p>  β-CD包合TCMTB的過程,實(shí)際就是水分子與TCMTB分子在范德華力的作用下,相互置換的重排和移去過程,會有

22、一個(gè)時(shí)間的平衡過程。包合時(shí)間的影響如圖2所示,包合時(shí)間由0.5h提高到2h時(shí),包合率增加很快,但是在2h以后,再延長包合時(shí)間,包合率提高不再明顯。這是因?yàn)樵黾影蠒r(shí)間能為β-環(huán)糊精和TCMTB提供更多的相互碰撞機(jī)會,有利于包合物的生成,提高包合率。但當(dāng)包合物充分形成后,β-CD的空腔已經(jīng)飽和,再增加包合時(shí)間,對促進(jìn)包合物的生成效果甚微,故選擇2h包合時(shí)間最佳。</p><p>  圖2 包合時(shí)間對包合率的影響&

23、lt;/p><p>  2.1.3包合溫度的影響影響分析</p><p>  通過對包合物形成過程的熱力學(xué)分析,環(huán)糊精分子空腔無論是在固相還是在水溶液中并非是空著的而是結(jié)合有水分子。由于范德華力和疏水鍵互相作用、氫鍵和釋放能量,電荷轉(zhuǎn)移和π-π堆積都是包合物形成和穩(wěn)定的驅(qū)動(dòng)力。伴隨包合物的形成會有明顯的熱量變化,因此溫度也是影響包合過程的重要因素。包合溫度過低,則β-環(huán)糊精在水中溶解度較小,不

24、利于包結(jié)絡(luò)合過程,此時(shí)ka迅速下降,影響包合向產(chǎn)物方向進(jìn)行。隨溫度的升高β-環(huán)糊精溶解度增加,包合溫度的影響如圖3所示,由圖3可知,在40~55℃之間,包合率隨溫度的升高而增加,在55℃包合率最高。但是當(dāng)包合溫度上升至70℃時(shí),包合率反而急劇降低。 這是因?yàn)樵谝欢囟确秶鷥?nèi),提高包合溫度能增加β-環(huán)糊精的溶解度,并為TCMTB的絡(luò)合提供動(dòng)能,促進(jìn)二者的相互碰撞幾率,有利于包合物的生成。但當(dāng)包合達(dá)到平衡后,過高的溫度又促進(jìn)了已形成的包合物

25、中的TCMTB的分子熱運(yùn)動(dòng),導(dǎo)致包合物的解絡(luò),故溫度為55℃為宜。</p><p>  圖3 包合溫度對包合率的影響</p><p>  2.2 正交試驗(yàn)結(jié)果與分析</p><p><b>  表2 均勻試驗(yàn)結(jié)果</b></p><p><b>  因素</b></p><p&

26、gt;  試驗(yàn)號 包合率(%)</p><p>  A B C</p><p>  1 1 1 1 71.45 </p><p>  2 1 2 2 78.37 </p><p>  3

27、 1 3 3 76.54 </p><p>  4 2 1 2 75.48 </p><p>  5 2 2 3 77.14 </p><p>  6 2 3 1 75.37 </

28、p><p>  7 3 1 3 63.79 </p><p>  8 3 2 1 68.74 </p><p>  9 3 3 2 71.52 </p><p>  k1 75.45 70.24

29、 71.85</p><p>  k2 76.00 74.75 75.12</p><p>  k3 68.02 74.48 72.49</p><p>  R 7.98 4.51 3.27</p><p>  通過單因素實(shí)驗(yàn)和正交實(shí)驗(yàn)得出的結(jié)果表明,在制備防霉劑TCMTB包合物的過程中,T

30、CMTB加入量、包合時(shí)間、包合溫度都是影響包合率的顯著因素,在這3個(gè)影響因素中,TCMTB加入量是最主要的影響因素,而包合時(shí)間和包合溫度是次要條件,包合的最佳工藝條件為A2B2C2,即TCMTB加入量為1.00g,包合時(shí)間2h,包合溫度55℃。在此最佳條件下包合率可達(dá)78.76%。</p><p>  2.3應(yīng)用實(shí)驗(yàn)評價(jià) </p><p>  表3 掛片法實(shí)驗(yàn)評價(jià)標(biāo)準(zhǔn)</p>

31、;<p>  樣品上霉菌的生長情況 霉菌抗性表示 防霉力評定等級 </p><p>  樣品表面霉菌不生長 - 0級</p><p>  試樣表面有微量菌絲(<10%) + 1級</p><p>  霉

32、菌少量生長(10%~30%) ++ 2級 </p><p>  霉菌大量生長(30%~60%) +++ 3級</p><p>  試樣表面布滿霉菌(>60%) ++++ 4級</p><p>  表4 掛片法加速實(shí)驗(yàn)結(jié)

33、果(天) (溫度 28℃)</p><p>  4天 8天 12天 16天 20天 24天 28天 </p><p>  1 2 1 2 1 2 1 2 1 2 1 2 1 2 </p><p>

34、  TCMTB原藥 - - - - - - - - - - + + + ++ </p><p>  TCMTB包合物 - - - - - - - - - - - - - -</p><p>  空白對照 + + + ++

35、++ +++ +++ +++ ++++ ++++ ++++ ++++ ++++ ++++ </p><p>  從表4中可以看出,防霉劑進(jìn)行包合后,其對霉菌的抑制時(shí)間相較于原藥大大延長,這是由于TCMTB防霉劑原藥在防霉抑菌時(shí)會很快釋放,抗菌效果難以持久,最終導(dǎo)致失效。而TCMTB被包合進(jìn)入β-環(huán)糊精空腔成為微膠囊后,它通過微膠囊的緩慢釋放而延長防霉時(shí)間,防霉劑由于高分子物質(zhì)的保護(hù)作用而使藥劑性能更為穩(wěn)定。

36、所以防霉劑包合物比原藥藥效散發(fā)慢,持續(xù)時(shí)間長,相應(yīng)降低了毒性和腐蝕性。</p><p><b>  3 結(jié) 論</b></p><p>  通過單因素實(shí)驗(yàn)和正交實(shí)驗(yàn),得到β-環(huán)糊精包合皮革防霉劑TCMTB的最佳工藝條件為:TCMTB加入量為1.0000g、包合時(shí)間為2h、包合溫度為55℃。然后對反應(yīng)產(chǎn)物進(jìn)行了熱重分析,證明β-CD-TCMTB包合物已經(jīng)形成。最后將TC

37、MTB包合物與TCMTB原藥進(jìn)行皮革防霉實(shí)驗(yàn)對比,證明了包合后的TCMTB防霉劑比原藥的藥效散發(fā)慢,對霉菌的抑制持續(xù)時(shí)間長。</p><p><b>  參考文獻(xiàn):</b></p><p>  [1]辜海彬,陳武勇.皮革防霉及防霉劑的研究進(jìn)展[J].中國皮革.2005,33(1):12-15.</p><p>  [2]李志堅(jiān),楊偉和,邱美堅(jiān).

38、皮革防霉劑的現(xiàn)狀與發(fā)展[J].廣東化工.2002,(2):14-15.</p><p>  [3]程霜.β-環(huán)糊精和染料木黃酮包合作用的研究[J].食品科學(xué).2006,(2):94-99.</p><p>  [4]周立斌,陳莉等. β-環(huán)糊精對芳香族氨基酸的包合作用研究[J].離子交換與吸附.2005,(2):159-167.</p><p>  [5]陳洪燕,萬

39、明.β-環(huán)糊精包合纈草揮發(fā)油的工藝研究[J].中國醫(yī)院藥學(xué)雜志.2005,(4):336-337.</p><p>  [6]Park CW, Kim SJ, Park SJ, et al. Inclusion complex of Conjugated Linoleic Acid(CLA) with Cyclodextrins[J].JagriFoodChem.2002,(50):2977-2983.</

40、p><p>  [7]葛艷蕊,王奎濤等.β-環(huán)糊精玫瑰香精微膠囊的制備[J].河北科技大學(xué)學(xué)報(bào).2004,(4):14-16.</p><p>  [8]程霜,杜凌云.β-環(huán)糊精和染料木黃酮包合作用的研究[J].食品科學(xué).2006,(2):94-99.</p><p>  [9]李志堅(jiān)等.皮革防霉劑TCMTB乳油的評價(jià)試驗(yàn)[J].廣州化工.2002,(2):34-36.

41、</p><p>  [10]文武等.新型皮革防霉劑3號藥效的研究[J].中國皮革.2002,(13):29-32.</p><p>  【責(zé)任編輯 王文深】</p><p><b> ?。ㄓ⑽陌?) </b></p><p>  Two regulations promulgated for implementat

42、ion is in the party in power for a long time and the rule of law conditions, the implementation of comprehensive strictly strategic plan, implementation in accordance with the rules and discipline to manage the party, st

43、rengthen inner-party supervision of major initiatives. The two regulations supporting each other, the < code > adhere to a positive advocate, focusing on morality is of Party members and Party leading cadres can se

44、e, enough to get a high</p><p>  The first party committee is mainly responsible for people, views of experts and scholars and grassroots party organizations and Party members. Approved by the Central Commit

45、tee of the Communist Party of China, on 7 September 2015, the general office of the Central Committee of the Party issued a notice to solicit the provinces (autonomous regions, municipalities) Party, the central ministri

46、es and commissions, state ministries and commissions of the Party (party), the General Political Departmen</p><p>  Discipline to protect the party's purpose. 8 of these regulations, a total of three ser

47、ies, Chapter 15, 178, more than 24000 words, after the revision of the regulations a total of 3 series, Chapter 11, 133, 17000 words, divided into "general" and "special provisions" and "Suppleme

48、ntary Provisions" Part 3. Among them, add, delete, modify the provisions of the proportion of up to nearly 90%. 1, the general general is divided into five chapters. The first chapter to the regulations of the guidi

49、ng </p><p>  10 categories of acts of violation of discipline integration revised into 6 categories, respectively, in violation of the punishments for acts of political discipline "in violation of disci

50、pline behavior of punishment" in violation of integrity of disciplinary action points "of violation punishments for acts of mass discipline" "the violation of work discipline, punishment" in viol

51、ation of discipline of life behavior punishment "6 chapters. 3, annex" Supplementary Provisions "clear authority mak</p><p>  Material; (III) harboring co personnel; (4) to the organization to

52、 provide false information, to hide the fact; (5) the him against the acts of the organization review. "< rule > add this clause to the Constitution requires more specific, the previous no punishment in accord

53、ance with the definite list and put forward clear punishment in accordance with. (4) about organizing or participating in superstitious activities as < Regulations > about engage in activities of feudal superstitio

54、n obstructi</p><p>  Human and the organizer shall not hold the corresponding position in the sorority; shall not borrow machine woven "network" and engage in kiss sparsely, round and round the gan

55、gs, but not "align" "Jieyi Gold Orchid" behavior. The third is to emphasize here that shall be organized to participate in the initiative to set up the villager, Alumni Association, comrades in arms.

56、The so-called 16 spontaneous was established mainly means without registration. Therefore, Party members include leading cad</p><p>  Expelled from the party. Party members and cadres of the spouses, childre

57、n and their spouses does the actual work and get salary or although the actual work but to receive significantly beyond the same rank salary standard, Party members and cadres informed fails to correct, in accordance wit

58、h the provisions of the preceding paragraph. "(3) about the gifts, gifts misconduct from handling practices in recent years, engaged in official cadres received gifts, gifts problems more prominent. This has</p&g

59、t;<p>  Main responsibility for poor discipline terms. (1) the new party organization comprehensive strictly the main responsibility of the party does not fulfill the 21 or perform poor disciplinary terms < New

60、 Regulations > has a lead people to pay attention to the new terms, that is, in chapter ten "on the violation of work discipline behavior punishment" increase in the one hundred and fourteenth "party fa

61、il to perform comprehensive strictly the main responsibility of the party or to perform comprehe</p><p>  And early method in combining Ji, increase accountability efforts. One is to two regulations within t

62、he party important basis, adhere to the party constitution duties, with strict discipline to maintain the constitution authority. The second is to adhere to high standards and keep the bottom line, adhere to Ji Yan in la

63、w and discipline, the discipline and rules quite in front, grasping grasping small, easily blame, comprehensive use of supervision and discipline of "four kinds of form" in the di</p><p>  Regulati

64、ons and discipline regulations of < < New Revision of the Communist Party of China clean fingered self-discipline criterion > and < Chinese Communist Party Disciplinary Regulations > is the Party Central C

65、ommittee in the new situation to promote the comprehensive strictly root of the lift, the regulations of the party construction of keeping pace with the times. We should study and implement the Standards > and < &g

66、t; as the primary political task, adhere to the party constitution duties, a</p><p>  District Ordinance < < rule > the constitution of discipline integration into a political discipline, organizati

67、on and discipline, honesty and discipline, discipline of the masses, work discipline, discipline, emphasize discipline, focusing on established rules, to draw the party organizations and Party members do not touch the bo

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