馬存強(qiáng),楊 超,周斌星,2,*,任小盈,李 靜,李發(fā)志
(1.云南農(nóng)業(yè)大學(xué)龍潤(rùn)普洱茶學(xué)院,云南 昆明 650201;2.安徽農(nóng)業(yè)大學(xué)茶與食品科技學(xué)院,安徽 合肥 230036;3.云南省保山市隆陽(yáng)區(qū)茶葉技術(shù)推廣站,云南 保山 678000)
微生物對(duì)茶葉中嘌呤生物堿代謝的研究進(jìn)展
馬存強(qiáng)1,楊 超1,周斌星1,2,*,任小盈1,李 靜1,李發(fā)志3
(1.云南農(nóng)業(yè)大學(xué)龍潤(rùn)普洱茶學(xué)院,云南 昆明 650201;2.安徽農(nóng)業(yè)大學(xué)茶與食品科技學(xué)院,安徽 合肥 230036;3.云南省保山市隆陽(yáng)區(qū)茶葉技術(shù)推廣站,云南 保山 678000)
嘌呤堿是茶葉中重要的內(nèi)含物質(zhì),常應(yīng)用于醫(yī)療保健和食品飲料等行業(yè)。在黑茶渥堆和茶葉微生物發(fā)酵期間嘌呤堿出現(xiàn)種類和含量的變化。為探究微生物與嘌呤堿代謝的關(guān)系,本文對(duì)近年國(guó)內(nèi)外相關(guān)研究進(jìn)行綜述,發(fā)現(xiàn)不同微生物單菌種發(fā)酵對(duì)嘌呤堿含量和種類影響不一,頂頭孢霉(Cephalosporium acremonium)能顯著提高茶葉中咖啡堿含量;煙曲霉(Aspergillus fumigatu)、乳酸菌(Lactobacillus)、醋酸型乳酸菌(acetic acid Lactobacillus)等對(duì)嘌呤堿含量影響不大;酵母菌(yeast)、聚多曲霉(Aspergillus sydowii)對(duì)咖啡堿有降低作用;黑曲霉(Aspergillus niger)對(duì)嘌呤堿代謝影響存在爭(zhēng)議;咖啡堿與茶葉堿存在消長(zhǎng)關(guān)系。
茶葉;微生物;嘌呤堿;咖啡堿;代謝
茶葉年人均消費(fèi)量已達(dá)0.5 kg,已經(jīng)超過(guò)咖 啡、啤酒、葡萄酒和碳酸飲料,成為第一大飲料[1]。這得益于人們對(duì)茶葉保健功效的認(rèn)識(shí)和認(rèn)可。大量在人體、動(dòng)物和實(shí)驗(yàn)室狀態(tài)下的研究表明,茶葉具有減少腰部脂肪堆積[2]、抗炎殺菌[2-3]、抗氧化[4]、減少動(dòng)脈粥樣硬化機(jī)率[5]和一定的防癌抗癌[6-8]等功效作用。這得益于茶葉中的功能成分,如茶多酚、茶色素、茶多糖、氨基酸等。嘌呤類生物堿亦是茶葉中重要的呈味物質(zhì)和功能成分。
茶葉生物堿主要為嘌呤類生物堿以及少量的嘧啶類生物堿。嘌呤類生物堿有咖啡堿(1,3,7-三甲基黃嘌呤,caffeine)、茶堿(1,3-二甲基黃嘌呤,theophylline)、可可堿(3,7-二甲基黃嘌呤,theobromine)、黃嘌呤(xanthine)、次黃嘌呤(hypoxanthine)、擬黃嘌呤(1,7-二甲基黃嘌呤,paraxanthine),以及在云南省苦茶中首次分離出的苦茶堿(1,3,7,9-四甲基尿酸,theacrine)[9]和云南普洱熟茶中分離鑒定出的8-氧化咖啡因(8-oxocaffeine)[10]。其結(jié)構(gòu)特點(diǎn)是以嘌呤環(huán)為基本骨架,嘌呤堿的種類取決于嘌呤環(huán)上甲基的位置和個(gè)數(shù)。嘧啶類生物堿有胸腺嘧啶脫氧核苷(deoxythymidine)、胸腺嘧啶(hymine)、尿嘧啶(uraci)。在普通品種中,咖啡堿占干質(zhì)量的2%~4%,可可堿約占0.05%,茶堿約占0.002%。
生物堿的種類和含量受到茶樹(shù)生長(zhǎng)的季節(jié)、品種以及茶葉加工工藝不同的影響。Wang等[11]對(duì)2009年4—9月生長(zhǎng)的茶鮮葉研究表明嘌呤類生物堿的含量隨季節(jié)起伏較大,并在8月份含量達(dá)到頂峰,咖啡堿含量相對(duì)穩(wěn)定,只有波浪狀起伏。在不同品種生物堿含量研究中,較具有代表性的為可可茶無(wú)性系品種[12],其鮮葉不含咖啡堿和茶堿,而是以可可堿為主;苦茶樹(shù)(Camellia assamica var. kucha)[13]的鮮葉中含有苦茶堿(1,3,7,9-四甲基尿酸),對(duì)咖啡堿引起的神經(jīng)系統(tǒng)興奮有抑制作用[9]。在對(duì)同為綠茶品種的龍井43號(hào)和安吉白茶的生物堿差異化研究中發(fā)現(xiàn),可可堿含量有顯著差異,咖啡堿差異明顯[14]。加工工藝的不同也造成了茶葉中生物堿含量的變化,一般咖啡堿含量高低的次序?yàn)椋杭t茶(完全發(fā)酵茶)>烏龍茶(半發(fā)酵茶)>綠茶(不發(fā)酵茶)[15]。同時(shí)也有研究表明隨著發(fā)酵程度的加深,咖啡堿和可可堿含量降低[16]。這或許與咖啡堿的存在形式、測(cè)定方法以及茶樹(shù)生長(zhǎng)地理環(huán)境、鮮葉的年齡和質(zhì)量有關(guān)(表1)。
表1 茶葉中主要嘌呤堿的功效與潛在危險(xiǎn)Table1 Efficacy and potential risks of principal purine alkaloids in tea
在普洱生茶、普洱熟茶、茯磚茶、康磚茶的加工與貯藏過(guò)程中,微生物大量參與并對(duì)茶葉的化學(xué)成分和品質(zhì)產(chǎn)生深遠(yuǎn)影響(表2)。早期普洱茶(普洱生茶)自然存放,通過(guò)自然環(huán)境中微生物類群作用以達(dá)到自然陳化[27]。對(duì)陳放15、25 年普洱生茶作微生物分離鑒定得到橙黃色游動(dòng)放線菌(Actinoplanes aurantiacus)、淡橘橙游動(dòng)放線菌(Actinoplanes pallidoaurantiacus)、絳紅褐游動(dòng)放線菌(Actinoplanes purpeobrunneus)、鏈霉屬桿菌(Streptomyces bacillaris)、卡伍爾鏈霉菌卡伍爾亞種(Streptomyces cavourensis subsp. cavourensis)、灰黑色鏈霉菌(Streptomyces cinereus)[28-29]。Zhao等[30]在2010年從60 個(gè)不同茶樣中分離出71 種真菌,鑒定出其中的63 種,分屬于19 個(gè)不同的屬,分別為曲霉屬(Aspergillus sp.)、青霉屬(Penicillium sp.)、酵母菌屬(yeast)、木霉屬(Trichoderma sp.)、芽枝霉菌屬(Cladosporium sp.)、子囊菌屬(Ascomycete sp.)和黏隔孢屬(Septogloeum sp.)、小球腔菌屬(Leptosphaeria sp.)、脈孢菌屬(Neurospora sp.)、踝節(jié)菌屬(Talaromyces sp.)、根毛菌屬(Rhizomucor sp.)、Pezia sp.、彎孢聚殼屬(Eutypella sp.)、肉座菌屬(Hypocrea sp.)、鐮刀霉菌(Fusarium sp.)、白腐菌屬(Phanerochaete sp.)、松慶病菌屬(Trametes sp.)、柯楠屬(Corynascus sp.)、犁頭霉菌屬(Absidia sp.)。普洱熟茶以云南曬青毛茶為原料,經(jīng)潮水渥堆加工而成。在普洱茶渥堆過(guò)程中分離出40余種真菌,分屬于19 個(gè)不同的屬,其中曲霉屬、青霉屬、酵母菌屬占普洱茶菌落的80%左右[31]。隨著溫度的升高,嗜熱菌在渥堆中后期大量出現(xiàn)[32],并鑒定為微小根毛霉(Rhizomucor pusilus)、牛根毛霉(Rhizomucor t a u r i c u s)、疏棉嗜熱絲孢菌(T h e r m o m y c e s lanuginosus)、埃莫森籃狀菌(Talaromyces emersonii)等嗜熱菌。黑曲霉[33]和酵母菌[34]被認(rèn)為是普洱茶的優(yōu)勢(shì)菌,并在普洱茶加工中得以應(yīng)用。茯磚茶與普洱茶同屬于黑茶范疇,以獨(dú)特的發(fā)花工序而著稱。茯磚茶中鑒定出的微生物有冠突散囊菌、間型散囊菌、匍匐散囊菌、謝瓦散囊菌、阿姆斯特丹散囊菌、赤散囊菌、散囊菌、黑曲霉、毛霉、擬青霉、草酸青霉、短密青霉、謝瓦氏曲霉、冠突曲霉等。優(yōu)勢(shì)菌群為冠突散囊菌(Eurotium cristatum(Raper & Fennell) Malloch & Cain)。冠突散囊菌在四川康磚茶中亦有檢出,對(duì)康磚茶品質(zhì)產(chǎn)生影響的微生物同時(shí)還有放線菌屬、毛霉屬和耐熱葡萄球菌等。以嶺頭單叢曬青毛茶為原料后發(fā)酵而成廣東陳香茶中的優(yōu)勢(shì)菌群分別為黑曲霉、產(chǎn)黃青霉和灰綠霉[35]。
綠茶、黃茶和白茶為不發(fā)酵或微發(fā)酵茶,加工過(guò)程應(yīng)杜絕微生物的參與,以避免污染。然而,微生物在茶的再加工與深加工有巨大應(yīng)用前景。酵母菌、真菌、細(xì)菌等三大微生物是影響紅茶品質(zhì)的最主要微生物,研究表明紅茶、烏龍茶中有益微生物的適度添加可顯著提高茶葉品質(zhì)[36]。
表2 茶葉加工中的微生物種類Table2 Major microorganism species during tea processing
3.1 自然渥堆發(fā)酵過(guò)程中嘌呤堿含量的變化
黑茶渥堆是以茶葉為基質(zhì),眾多微生物參與的固態(tài)發(fā)酵過(guò)程。在普洱茶渥堆期間,水浸出物略微下降、茶多酚含量大幅度下降、茶褐素急劇上升[37-38]。不同產(chǎn)地的普洱茶咖啡堿含量無(wú)顯著性差異。在普洱茶自然渥堆過(guò)程中,咖啡堿略有上升[39]。Wang Di等[40]研究與之相反,渥堆末期咖啡堿含量較原料有所降低。這或許與渥堆過(guò)程中優(yōu)勢(shì)菌種的差異相關(guān)。在普洱茶渥堆期間添加發(fā)酵劑可加快咖啡堿的變化,降低熟茶的生產(chǎn)周期。在利用添加鮮葉浸提物的微生物發(fā)酵實(shí)驗(yàn)中[41],浸提物的添加可降低咖啡堿的含量,而菌種不同會(huì)對(duì)咖啡堿產(chǎn)生不同的結(jié)果。
3.2 可降解咖啡堿菌株的篩選
為了生產(chǎn)低咖啡堿茶葉(咖啡堿含量小于1%),國(guó)內(nèi)外科技工作者采取熱水浸提、超臨界CO2提取、有機(jī)物萃取等物理化學(xué)方法脫去茶葉中多余的咖啡堿,或通過(guò)雜交育種選育低咖啡堿的茶樹(shù)新品種。通過(guò)茶、咖啡園土壤篩選可降解咖啡堿的菌株同樣取得可喜成果。利用咖啡堿作為唯一碳源和氮源,Gokulakrishnan等[42]從土壤中篩選出Pseudomonas sp. GSC1182菌株,該菌株在48 h內(nèi)能降解掉培養(yǎng)基中80%的咖啡堿。Brand等[43]研究發(fā)現(xiàn)微生物的咖啡堿降解效率與溫度有關(guān),曲霉菌和青霉菌等真菌在25 ℃條件下的降解率為100%,在30 ℃條件下時(shí)僅為80%。國(guó)內(nèi)同樣有相關(guān)研究[44-45],栗娜等[44]在杭州茶園篩選出對(duì)咖啡堿降解效率達(dá)100%的菌株,經(jīng)分子學(xué)鑒定為假單胞菌屬的Pseudomonas lutea。柴潔[45]以普洱茶渥堆茶樣為實(shí)驗(yàn)材料,篩選出可降解咖啡堿菌株,經(jīng)18S rDNA測(cè)序鑒定為聚多曲霉(Aspergillus sydowii NRRL250),并進(jìn)行單菌落茶葉發(fā)酵發(fā)現(xiàn),咖啡堿含量大幅度下降,至末期含量甚微;茶葉堿含量大幅度上升,末期時(shí)茶葉堿含量達(dá)2.814%??Х葔A與茶葉堿存在消長(zhǎng)關(guān)系。在微生物發(fā)酵過(guò)程中,咖啡堿存在著與植物中咖啡堿相似的降解途徑。
3.3 單菌株茶葉發(fā)酵嘌呤堿含量變化
對(duì)不同微生物單菌株發(fā)酵的研究證實(shí)不同微生物對(duì)嘌呤堿含量和種類影響不一(表3)。利用頂頭孢霉的單菌落發(fā)酵普洱茶過(guò)程中咖啡堿含量大幅度上升[46]。在Qin Jinhua等[47]研究中證實(shí)煙曲霉(Aspergillus fumigatu)對(duì)咖啡堿和可可堿的含量影響不大,黑曲霉(Aspergillus niger)可顯著降低咖啡堿的含量。Wang Xiaogang等[48]對(duì)不同微生物對(duì)茶葉發(fā)酵過(guò)程中咖啡堿及生物堿含量的研究發(fā)現(xiàn),Tieghem ACCC30005、R. arrhizus Fisher3.2893和M. circinelloides van. Tieghem AS3.2484,能夠提高發(fā)酵過(guò)程中咖啡堿的含量而酵母菌、C. albicans(Robin)Berkhout ACCC2100和C. famata(Saito)Lodder ACCC2052能夠降低發(fā)酵過(guò)程中咖啡堿的含量。這與Pasha等[49]研究酵母菌能降低紅茶發(fā)酵咖啡堿含量的結(jié)論相符。在黑曲霉發(fā)酵普洱茶過(guò)程中咖啡堿含量略有上升,與Wang Xiaogang等[48]結(jié)果不一致。Nishino等[50]通過(guò)乳酸菌和醋酸型乳酸菌對(duì)濕潤(rùn)的綠茶廢料發(fā)酵,發(fā)現(xiàn)咖啡堿含量沒(méi)有明顯變化。研究冠突散囊菌[51]對(duì)綠茶液發(fā)酵過(guò)程中的影響,在0~8 d的發(fā)酵液中咖啡堿含量保持穩(wěn)定,隨著菌絲體的產(chǎn)生,咖啡堿下降到11.97 mg/mL。
表3 不同微生物對(duì)嘌呤類生物堿的影響Table3 Effects of different microorganisms on purine alkaloids
目前,在普洱茶以及黑茶渥堆發(fā)酵與陳化過(guò)程中分離鑒定出超過(guò)71 株真菌,6 株放線菌和7類細(xì)菌。另外有5 類微生物被證實(shí)對(duì)咖啡堿有顯著降解作用。這為研究微生物與咖啡堿等嘌呤堿的關(guān)系以及低咖啡堿茶葉的生產(chǎn)提供了豐富的菌種來(lái)源。在以曬青毛茶、綠茶、紅茶等不同茶葉為基質(zhì)的微生物發(fā)酵中,黑曲霉、酵母菌、頂頭孢霉、聚多曲霉等真菌對(duì)茶葉中咖啡堿含量有顯著影響。煙曲霉、乳酸菌、醋酸型乳酸菌、冠突散囊菌等微生物對(duì)咖啡堿、可可堿等嘌呤堿含量產(chǎn)生或多或少的影響。而茶葉微生物發(fā)酵過(guò)程中,咖啡堿、可可堿、茶葉堿等嘌呤堿的代謝途徑尚不清晰;不同嘌呤堿之間的消長(zhǎng)關(guān)系和內(nèi)在聯(lián)系值得進(jìn)一步研究。
[1] RIETVELD A, WISEMAN S. Antioxidant effects of tea: evidence from human clinical trials[J]. The Journal of Nutrition, 2003, 133(10): 3285S-3292S.
[2] KUBOTA K, SUMI S, TOJO H, et al. Improvements of mean body mass index and body weight in preobese and overweight Japanese adults with black Chinese tea (Pu-erh) water extract[J]. Nutrition Research, 2011, 31(6): 421-428.
[3] HU Yongjin, JIA Junjing, QIAO Jingling, et al. Antimicrobial activity of Pu-erh tea extracts in vitro and its effects on the preservation of cooled mutton[J]. Journal of Food Safety, 2010, 30(1): 177-195.
[4] SU Yajuan, ZHANG Chenlu, WANG Yan, et al. Antibacterial property and mechanism of a novel Pu-erh tea nanofibrous membrane[J]. Applied Microbiology and Biotechnology, 2012, 93(4): 1663-1671.
[5] GONG Jiashun, PENG Chunxiu, HE Xiang, et al. Antioxidant activity of extracts of Pu-erh tea and its material[J]. Asian Journal of Agricultural Sciences, 2009, 1(2): 48-54.
[6] HOU Yan, SHAO Wanfang, XIAO Rong, et al. Pu-erh tea aqueous extracts lower atherosclerotic risk factors in a rat hyperlipidemia model[J]. Experimental Gerontology, 2009, 44(6): 434-439.
[7] ZHAO Hang, ZHANG Min, ZHAO Lu, et al. Changes of constituents and activity to apoptosis and cell cycle during fermentation of tea[J]. International Journal of Molecular Sciences, 2011, 12(3): 1862-1875.
[8] WAY T D, LIN Huiyi, KUO D H, et al. Pu-erh tea attenuates hyperlipogenesis and induces hepatoma cells growth arrest through activating AMP-activated protein kinase (AMPK) in human HepG2 cells[J]. Journal of Agricultural and Food Chemistry, 2009, 57(12): 5257-5264.
[9] 折改梅, 陳可可, 張穎君, 等. 8-氧化咖啡因和嘧啶類生物堿在普洱熟茶中的存在[J]. 云南植物研究, 2007, 29(6): 713-716.
[10] 王冬梅, 盧嘉麗, 程悅, 等. 苦茶的急性毒性與神經(jīng)藥理活性初步研究[J]. 中山大學(xué)學(xué)報(bào): 自然科學(xué)版, 2010, 49(1): 76-79.
[11] WANG L Y, WEI K, JIANG Y W, et al. Seasonal climate effects on flavanols and purine alkaloids of tea (Camellia sinensis L.)[J]. European Food Research and Technology, 2011, 233(6): 1049-1055.
[12] 何玉媚, 彭力, 李成仁, 等. 可可茶無(wú)性系品種的生化成分研究[J].廣東農(nóng)業(yè)科學(xué), 2011, 38(6): 10-13.
[13] YE Chuangxing, HIROSHI A, ZHENG Xinqiang, et al. New discovery of pattern of purine alkaloids in wild tea trees[J]. Acta Scientiarum Naturalium Universitatis Sunyatseni, 2002, 42(1): 62-65.
[14] WEI Kang, WANG Liyuan, ZHOU Jian, et al. Comparison of catechins and purine alkaloids in albi no and normal green tea cultivars (Camellia sinensis L.) by HPLC[J]. Food Chemistry, 2012, 130(3): 720-724.
[15] ZUO Yuegang, CHEN Hao, DENG Yiwei. Simultaneous determination of catechins, caffeine and gallic acids in green, Oolong, black and Pu-erh teas using HPLC with a photodiode array detector[J]. Talanta, 2002, 57(2): 307-316.
[16] KIM Y, GOODNER K L, PARK J D, et al. Changes in antioxidant phytochemicals and volatile composition of Camellia sinensis by oxidation during tea fermentation[J]. Food Chemistry, 2011, 129(4): 1331-1342.
[17] 翟心慧, 王志華, 吳清華, 等. 咖啡堿對(duì)蟾蜍坐骨神經(jīng)干動(dòng)作電位和離體心臟活動(dòng)的影響[J]. 中國(guó)應(yīng)用生理學(xué)雜志, 2008, 24(4): 397-398; 467.
[18] 崔秋, 李鼎鋒, 尉承澤, 等. 咖啡因在骨肉瘤細(xì)胞株順鉑化療中增效作用的實(shí)驗(yàn)研究[J]. 解放軍醫(yī)學(xué)雜志, 2008, 33(5): 582-583; 592.
[19] CULPITT S V, de MATOS C, RUSSELL R E, et al. Effect of theophylline on induced sputum inf l ammatory indices and neutrophil chemotaxis in chronic obstructive pulmonary disease[J]. American Journal of Respiratory and Critical Care Medicine, 2002, 165(10): 1371-1376.
[20] 原紅, 董莉, 張英民. 茶堿對(duì)慢性阻塞性肺疾病穩(wěn)定期誘導(dǎo)痰白細(xì)胞介素-8及肺功能的影響[J]. 中國(guó)實(shí)用醫(yī)藥, 2011, 6(5): 28-29.
[21] 朱崢, 周奇興, 張?jiān)气P, 等. 茶堿治療慢性阻塞性肺病急性加重期的療效[J]. 中國(guó)藥師, 2010(7): 1006-1008.
[22] XU Jiekun, KURIHARA H, ZHAO Liang, et al. Theacrine, a special purine alkaloid with sedative and hypnotic properties from Cammelia assamica var. Kucha in mice[J]. Journal of Asian Natural Products Research, 2007, 9(7): 665-672.
[23] SHILO L, SABBAH H, HADARI R, et al. The effects of coffee consumption on sleep and melatonin secretion[J]. Sleep Medicine, 2002, 3(3): 271-273.
[24] BUERGE I J, POIGER T, MüLLER M D, et al. Caffeine, an anthr opogenic marker for wastewater contamination of surface waters[J]. Environmental Science & Technology, 2003, 37(4): 691-700.
[25] 潘集陽(yáng), 廖繼武, 田徑, 等. 神經(jīng)肽Y系統(tǒng)在高劑量咖啡因, 可可堿誘導(dǎo)的大鼠焦慮行為中的作用機(jī)制[J]. 實(shí)用醫(yī)學(xué)雜志, 2011, 27(18): 3298-3300.
[26] 王園園, 楊曉絨, 莫昉, 等. 苦茶堿對(duì)大鼠的長(zhǎng)期毒性實(shí)驗(yàn)研究[J].時(shí)珍國(guó)醫(yī)國(guó)藥, 2010, 21(10): 2439-2441.
[27] HUANG Jianping, WU Chucai. Distribution of the microorganism groups in the air of forest area[J]. Scientia Silvae Sinicae, 2002, 38(2): 173-176.
[28] CHEN Y S, LIU Binglan, CHANG Y N. Bioactivities and sensory evaluation of Pu-erh teas made from three tea leaves in an improved pile fermentation process[J]. Journal of Bioscience and Bioengineering, 2010, 109(6): 557-563.
[29] CHEN C S, CHAN H C, CHANG Y N, et al. Effects of bacterial strains on sensory quality of Pu-erh tea in an improved pile-fermentation process[J]. Journal of Sensory Studies, 2009, 24(4): 534-553.
[30] ZHAO Z J, TONG H R, ZHOU L, et al. Fungal colonization of Pu-erh tea in Yunnan[J]. Journal of Food Safety, 2010 , 30(4): 769-784.
[31] 趙振軍, 童華榮, 周黎, 等. 普洱茶中真菌種群的分離與分子鑒定[J].茶葉科學(xué), 2009, 29(6): 436-442.
[32] 楊瑞娟, 呂杰, 嚴(yán)亮, 等. 普洱茶渥堆發(fā)酵中嗜熱真菌的分離和鑒定[J].茶葉科學(xué), 2011, 31(4): 371-378.
[33] XU X, YAN M, ZHU Y. Influence of fungal fermentation on the development of volatile compounds in the Puer tea manufacturing process[J]. Engineering in Life Sciences, 2005, 5(4): 382-386.
[34] ABE M, TAKAOKA N, IDEMOTO Y, et al. Characteristic fungi observed in the fermentation process for Puer tea[J]. International Journal of Food Micr obiology, 2008, 124(2): 199-203.
[35] 陳棟, 李晶晶, 方祥, 等. 廣東陳香茶后發(fā)酵過(guò)程中主要微生物種群和酶類活性變化的研究[J]. 茶葉科學(xué), 2010, 30(6): 429-434.
[36] 李萍, 劉通訊. 微生物發(fā)酵對(duì)烏龍茶內(nèi)在品質(zhì)的影響[J]. 現(xiàn)代食品科技, 2008, 24(8): 773-776.
[37] 田軍, 沈舫, 梁自達(dá), 等. 普洱茶渥堆過(guò)程中總水溶性碳水化合物和茶多酚的變化分析[J]. 價(jià)值工程, 2011(29): 313-314.
[38] ZHANG Liang, LI Ning, MA Zhizhong, et al. Comparison of the chemical constituents of aged Pu-erh tea, ripened Pu-erh tea, and other teas using HPLC-DAD-ESI-MSn[J]. Journal of Agricultural and Food Chemistry, 2011, 59(16): 8754-8760.
[39] LIANG Yuerong, ZHANG Lingyun, LU Jianliang. A study on chemical estimation of Pu-erh tea quality[J]. Journal of the Science of Food and Agriculture, 2005, 85(3): 381-390.
[40] WANG Di, ZHONG Ying, LUO Xiao, et al. Pu-erh black tea supplementation decreases quinocetone-induced ROS generation and oxidative DNA damage in Balb/c mice[J]. Food and Chemical Toxicology, 2011, 49(2): 477-484.
[41] HOU C W, JENG K C, CHEN Y S. Enhancement of fermentation process in Pu-erh tea by tea-leaf extract[J]. Journal of Food Science, 2010, 75(1): H44-H48.
[42] GOKULAKRISHNAN S, CHANDRARAJ K, GUMMADI S N. A preliminary study of caffeine degradation by Pseudomonas sp. GSC 1182[J]. International Journal of Food Microbiology, 2007, 113(3): 346-350.
[43] BRAND D, PANDEY A, ROUSSOS S, et al. Biological detoxification of coffee husk by filamentous fungi using a solid state fermentation system[J]. Enzyme and Microbial Technology, 2000, 27(1): 127-133.
[44] 栗娜, 籍保平, 李博, 等. 可降解咖啡堿菌株的篩選與鑒定[J]. 食品科學(xué), 2010, 31(21): 218-221.
[45] 柴潔. 優(yōu)勢(shì)菌株發(fā)酵普洱茶咖啡堿含量的影響[D]. 昆明: 云南農(nóng)業(yè)大學(xué), 2013.
[46] 陳華紅, 李雪玲, 巖燕, 等. 頂頭孢霉對(duì)普洱茶品質(zhì)的影響[J]. 食品科技, 2011, 36(10): 53-56; 61.
[47] QIN Jinhua, LI Ning, TU Pengfei, et al. Change in tea polyphenol and purine alkaloid composition during solid-state fungal fermentation of postfermented tea[J]. Journal of Agricultural and Food Chemistry, 2012, 60(5): 1213-1217.
[48] WANG Xiaogang, WAN Xiaochun, HU Shuxia, et al. Study on the increase mechanism of the caffeine content during the fermentation of tea with microorganisms[J]. Food Chemistry, 2008, 107(3): 1086-1091.
[49] PASHA C, REDDY G. Nutritional and medicinal improvement of black tea by yeast fermentation[J]. Food Chemistry, 2005, 89(3): 449-453.
[50] NISHINO N, KAWAI T, KONDO M. Changes during ensilage in fermentation products, tea catechins, antioxidative activity and in vitro gas production of green tea waste stored with or without dried beet pulp[J]. Journal of the Science of Food and Agriculture, 2007, 87(9): 1639-1644.
[51] 徐瑞瑞, 李立祥, 倪媛, 等. 綠茶液冠突散囊菌發(fā)酵期間品質(zhì)變化的研究[J]. 安徽農(nóng)業(yè)大學(xué)學(xué)報(bào), 2010, 37(3): 478-482.
Recent Progress in Microbial Metabolism of Purine Alkaloids in Fermented Tea
MA Cun-qiang1, YANG Chao1, ZHOU Bin-xing1,2,*, REN Xiao-ying1, LI Jing1, LI Fa-zhi3
(1. LongRun Pu-erh Tea College, Yunnan Agricultural University, Kunming 650201, China; 2. College of Tea and Food Science and Technology, Anhui Agricultural University, Hefei 230036, China; 3. Yunnan Province Baoshan City Longyang Tea Technical Extension Station, Baoshan 678000, China)
As important substances present in tea, purine alkaloids are often employed in medicine and health care as well as drinks. The kinds and contents of purine alkaloids are potentially changed during microbial fermentation of tea. After reviewing recent literature regarding the association of microorganisms with the metabolism of purine alkaloids in fermented tea, this article fi nds that different strains, when used individually to ferment tea, have different effects on the kinds and contents of purine alkaloids. C ephalosporium acremonium can substantially enhance caffeine c ontents in tea, Aspergillus fumigatu, Lactobacillus, and acetic acid Lactobacillus have little impact on the contents purine alkaloids, and yeast and Aspergillus sydowii NRRL 250 can reduce caffeine contents. However, the effect of Aspergillus niger on purine alkaloid metabolism remains controver sial. In addition, a trade-off relationship between caffeine and theophyllin e exists during tea fer mentation.
tea; microorganism; purine alkaloids; caffeine; metabolism
S571.1
A
1002-6630(2014)21-0292-05
10.7506/spkx1002-6630-201421057
2013-12-27
“十一五”國(guó)家科技支撐計(jì)劃項(xiàng)目(2007BAD58B03);保山市科技項(xiàng)目-保山市特種茶葉開(kāi)發(fā)與研究項(xiàng)目
馬存強(qiáng)(1988—),男,碩士研究生,研究方向?yàn)椴枞~加工與綜合利用。E-mail:macunqiang1208@aliyun.com
*通信作者:周斌星(1963—),男,副教授,博士,研究方向?yàn)椴枞~加工。E-mail:bxzhou01@126.com