Chemical Compositions of the Leaf Essential Oils of <i>Aralia spinosa</i>from Three Habitats in Northern Alabama

Aralia spinosa leaves were collected from three different habitats in north Alabama. The leaf essential oils were collected by hydrodistillation and analyzed by gas chromatography / mass spectrometry (GC-MS). The most abundant components of A. spinosa essential oils were the sesquiterpenes germacrene D (28.0% - 37.3%), (E)-caryophyllene (8.2% - 15.7%), and α-humulene (1.9% - 4.9%);the monoterpene myrcene (up to 15.1%), and the fatty-acid-derivative (2E)-hexenal (trace to 28.9%). Fatty-acid derivatives and monoterpene hydrocarbons were more abundant in samples from suburban Huntsville than those from “natural” habitats (Monte Sano Mountain, Wheeler National Wildlife Refuge), while sesquiterpene hydrocarbons were more abundant in the natural/wild samples.

Effect of Cassava Leaf (<i>Manihot esculenta </i>) Level in Guinea-Pigs (<i>Cavia porcellus </i>) Meal on the Physico-Chemical and Techno-logical Properties of Its Meat

The present study was carried out to evaluate the effect of different rates of dried cassava leafs in diet as replacement of protein sources on the weight gain and carcass yield of guinea-pigs, as well as on the physico-chemical and technological properties of guinea-pigs’ meat. A total of forty-eight (48) eight-week-old guinea-pigs were divided in a completely randomized experimental design, in four groups and fed with the experimental foods. These experimental foods were formulated as follows: cassava-leaf (Manihot esculenta) powder was incorporated at concentrations of 0%, 8%, 10% and 12% respectively in replacement of protein sources for R0, R1, R2 and R3. Each treatment consisted of a group of 12 guinea pigs per paddock (6 males and 6 females). The initial weight (IW), final weight (FW), daily weight gain (DWG) and total gain (TG) were evaluated. At the 22nd week, animals of each group were sacrificed by bleeding, then skinned and eviscerated. Carcasses were cut, and some parts (loin, thigh and shoulder) were collected, deboned and analysed. The highest FW and carcass yield (CY) were obtained with the use of 10% cassava leafs (R2): 556 g (FW), 42.65% (CY) for males and 529.17 g (FW), 37.39% (CY) for females. The incorporation of 8% (R1) and 12% (R3) cassava leafs led to a significant increase (P < 0.05) in protein levels in the loins (22.89%) and shoulders (22.43%) of females and the thighs (21.68%) and shoulders (21.09%) of males. However, protein levels of male fed with R3 in the various parts studied were higher than females fed with the same diet. The study of the technological parameters of guinea-pig’s meat showed that the incorporation of 8% and 12% cassava leafs in the diet resulted in a significant decrease in the water holding capacity and technological yield in the different parts studied. These results show that, the incorporation of cassava leafs in guinea-pigs’ diet made it possible to obtain good growth (R2) and meat of good technological quality.

Study on Chemical Characteristics of Rainfall in Tobacco-Growing Regions of Chenzhou, Hunan Province

In order to clarify the chemical properties of rainfall in typical tobacco areas in Chenzhou City, Hunan Province, and analyze its potential for soil and flue-cured tobacco planting, rainfall samples in 2020 were collected by rainfall instruments in Fangyuan Town and Aoquan Town of Guiyang County, and the chemical properties that are closely related to the quality of flue-cured tobacco were determined, such as pH, EC, total nitrogen (TN), nitrate nitrogen (), ammonium nitrogen () and ion concentrations (K+, Na+, Ca2+, Mg2+, , Al3+, , Cl−,). The results show that the pH values of rainfall samples at Fangyuan and Aoquan monitoring sites are in the range of 4.92 - 6.17 and 4.93 - 5.69 respectively, with an average of 5.27 and 5.27 respectively. The acid rain characteristic is very obvious, which is mainly dominated by . The variation of rainfall EC has seasonal characteristics. EC is low from January to September, in the range of 6.09 - 56.72 and 11.83 - 30.93 μS/cm respectively, besides, it is high from October to December, in the range of 102.63 - 174.60 and 25.05 - 86.37 μS/cm respectively. The annual deposition of TN was 22.19 and 20.76 kg/hm2/yr respectively, which were higher than that in the western regions with less human disturbance, but lower than or equal to that in the developed agricultural regions in eastern China. The proportion of in the annual deposition of TN was higher than that of at two monitoring sites, with an average of 56.51% and 38.86% respectively. Ammonia volatilization from agricultural activities contributed more to rainfall nitrogen content. The ratios of ammonium nitrogen to nitrate nitrogen deposition at two monitoring points were 1.84, 1.81, 1.86 and 1.34, 1.46, and 1.29 during the whole year, summer and autumn, winter and spring respectively. The ratio is higher in summer and autumn than in winter and spring. The weighted average equivalent concentrations of the main ions at two monitoring sites were 238.88 μeq/L and 211.21 μeq/L respectively, and the orders of the ion concentrations were slightly different. Both the concentrations of and are higher, while Mg2+, and Al3+ are lower. , and are mainly from human activities with a contribution rate between 91.90% and 99.35%. Ca2+ mainly comes from soil and ground dust, besides, Cl− and Mg2+ mainly come from marine sources and K+ mainly comes from terrestrial sources. In general, the acidic rainfall and higher concentration are beneficial to reducing the high pH value of soil in Aoquan tobacco area and improving the quality of flue-cured tobacco. Higher concentrations of and in rainfall are not conducive to the improvement of flue-cured tobacco quality, because of the high content of soil available sulfur in Chenzhou tobacco area and the characteristics of flue-cured tobacco’s preference for ammonium.

Component Composition of Essential Oils <i>Curcuma longa</i>L. (Zingiberaceae) Introduced in Uzbekistan

This article presents the results of studying the component composition of essential oils of leaves and rhizomes of C. longa grown in Uzbekistan. The chemical composition of essential oils of vegetative organs of the Curcuma longa (Zingiberaceae) plant introduced in Uzbekistan was studied for the first time. Essential oils of the plant were isolated by hydrodistillation, their chemical composition was studied by chromatography-mass spectrometry. In the composition of essential oils of leaves and rhizomes C. longa L., introduced in the Tashkent oasis, found 27 and 16 components, respectively, among which the leaf is dominated by α-fellandren (33.79%), α-terpinolene (24.28%), n-cymene (12.27%), eucalyptol (9.77%), and in the rhizomes-6-(1,3-dimethyl-buta-1,3-dienyl)-1,5,5-trimethyl-7-oxa-bicyclo [4.1.0] hept-2-EN (22.77%), α-curcumene (4.11%), 2,6,6,9-tetramethyl-tricyclo [5.4.0.0(2.8)] undec-9-EN (3.81%), α-zedren (1.14%), as well as 3 components that were not identified (the mass spectrum did not match the library data) their mass fraction was 47.47%, 10.41% and 3.46%. The composition of leaves and rhizomes of C. longa differ quantitatively and in quality. For example, α-curcumene in percentage content is more contained in rhizomes, and α-fellandren, which is the dominant content in leaves, is not found in the underground part.

3种类型烟草种质资源烟叶生物碱等化学成分差异性分析

为筛选能为科研、生产和育种利用的优异烟草种质资源。对来源于国内外的141份烤烟、18份白肋烟和6份雪茄烟的烟叶常规化学成分和主要生物碱进行检测、比较和聚类分析。结果表明:总糖和还原糖含量以烤烟最高,总氮、烟碱和氧化钾以白肋烟种质最高。总植物碱和烟碱含量以烤烟种质自来黄2243最高,雪茄烟种质Dutch(Ohio)最低;降烟碱和烟碱转化率以烤烟种质平板柳叶最高,以烤烟种质二性子和白肋烟种质Burley11B最低。聚类分析将165份种质分成4类,烤烟种质主要集中在第1和第4类,其主要特征是总糖和还原糖含量较高,烟碱转化率较低;第2类的总糖和还原糖含量低,总氮、总植物碱和氧化钾含量高;第3类的烟碱和总植物碱含量低,降烟碱含量高,烟碱转化率高。不同类型种质资源的化学成分和生物碱差异明显,筛选出的不同梯度烟碱的种质可为烟碱的进一步研究提供材料支撑。

不同尺寸和结构的烟梗吸湿特性及其成因

【目的】研究细梗、中等梗、拐头的吸湿特性及其成因,以优化不同尺寸和结构的烟梗分组加工技术。【方法】采用自主研制的烟梗热湿特性分析装置考察3种烟梗的吸湿特性,使用扫描电镜观测样品表皮和梗横断面的微观结构,利用连续流动分析仪检测烟梗的化学组成。【结果】细梗、中等梗、拐头吸湿能力依次降低,随着空气湿度的增大,吸湿速率和平衡含水率增大,其吸湿曲线符合Weibull模型。细梗、中等梗、拐头表皮的气孔数量依次减少;中等梗和细梗横断面的气孔明显大于拐头的气孔。细梗、中等梗、拐头的总糖、还原糖和总植物碱含量依次减少,蛋白质含量依次增加。【结论】细梗、中等梗、拐头的吸湿速率与其孔隙发达程度正相关,且吸湿速率随着空气湿度的增大而增大;拐头、中等梗、细梗的平衡含水率依次增大,原因是其总糖(或还原糖)含量依次增大,提供了更多的水分吸附位点。不同尺寸和结构烟梗的吸湿特性差异明显,有必要按照尺寸和结构对烟梗进行分组加工。

有机肥+生物炭+微生物菌剂配施对烤烟多酚和化学成分的影响

以云烟87为研究对象,采用三因素三水平正交试验设计,设置3个生物炭(900、1800、2700 kg/hm^(2))、3个微生物菌剂(30、60、90 kg/hm^(2))和3种有机肥(羊粪肥、芝麻饼肥、菜籽饼肥)组合成9个处理,并以无机肥为对照处理,研究了上述因素对烤后烟叶多酚类和常规化学成分的影响。结果表明:生物炭施用量是影响烤烟的多酚和化学成分含量的主效因素,随着生物炭施用量的增加,烟叶的总糖、还原糖及各种多酚类物质含量均有所增加,施用2700 kg/hm^(2)生物炭的整体表现较优。微生物菌剂也是重要的影响因素,随着微生物菌剂施用量的增加,烟叶的总糖、还原糖、多酚类、绿原酸含量均有所增加,施用60 kg/hm^(2)微生物菌剂的整体表现较优。施用有机肥的影响则较小,其中,羊粪肥的表现相对较好。综上,最佳组合方式为2700 kg/hm^(2)生物炭+60 kg/hm^(2)微生物菌剂+羊粪肥,并且将其可应用于凉山产区烤烟的施肥管理中。

生物有机肥与化肥减量配施对土壤养分及烟叶产质量的影响

为减少化肥的过量施用,提高湖南宜章植烟土壤肥力和烟叶生产效益,以烤烟品种‘K326’为材料,采用田间试验研究了不同比例生物有机肥与化肥减量配施对土壤养分及烟叶产量与品质的影响。结果表明:增施适当比例生物有机肥配合化肥减量能不同程度地改善土壤肥力质量,促进烟株的生长。随着生物有机肥比例的增加与化肥用量的减少,烤烟的各项生长农艺性状、感官评吸质量、产量、产值以及上等烟比例呈先升后降的趋势。其中,以减量20%化学追肥的T2处理对烟株的生长和烟叶的品质表现最好。与常规施肥的对照(CK)相比,烟草株高、有效叶片数和最大叶面积分别增加8.24%~17.00%、13.81%~23.22%和12.63%~16.86%,C3F烟叶中总糖和钾含量分别达到26.51%~30.01%和2.16%~2.86%,C3F和B2F烟叶的感官评吸质量分别提高1.67%~2.98%和3.12%~4.10%,烟叶产量、上等烟比例和产值分别提高3.76%~6.58%、3.38%~3.79%和8.24%~9.58%。研究结果为湘南植烟区应用生物有机肥与化肥减量配施提供了科学参考依据。

山东省不同类型烟叶质量特征差异及原因分析

为明确山东省不同类型烟叶质量特征差异及原因,本研究连续3年采集山东烟区烟叶样品,分析不同类型烟叶物理特性、化学成分和感官评吸质量,通过相关分析,解析影响评吸质量的主要因素。结果表明:中、上部叶物理特性方面,香吃味型最好,香味型居其次,吃味型最低,表现在部分吃味型中、上部叶发育过旺,叶片大小、单叶重、叶面密度超出适宜范围。化学成分方面,香味型中部叶化学成分协调性最好,香吃味型中部叶居于其次,吃味型中部叶最低,主要是部分吃味型烟叶淀粉、氯离子含量高且钾氯比低;3种类型上部叶化学成分协调性基本一致。感官评吸质量方面,中部叶质量得分为香味型最高,香吃味型其次,吃味型最低,差异主要体现在香气质、余味、杂气、刺激性等指标;3种类型上部烟叶评吸质量差异不明显。相关分析表明,叶宽对中部叶评吸质量产生显著负效应,叶长、叶片厚度对上部叶评吸质量产生显著负效应;钾和钾氯比对中部叶评吸质量产生显著正效应,而还原糖、硫、氯离子、纤维素、半纤维素产生显著负效应;还原糖、总糖对上部叶评吸质量产生显著正效应,而烟碱、纤维素产生负效应。吃味型中部叶评吸质量较低,与其叶片发育过旺及硫、氯含量较高有关;3种类型上部叶评吸质量无显著差异,但其原因各有不同,香味型、香吃味型上部叶虽然钾含量高、氯离子含量低,但总糖含量低、烟碱含量高,糖碱比协调性变差,而吃味型上部叶钾含量低、氯离子含量高,总糖含量高、烟碱含量低,糖碱比协调。因此,需针对不同类型烟叶的问题,采取相应农艺措施,提高烟叶质量。

箱式烘烤烟叶化学成分变化与温湿度耦合分析

为研究箱式烘烤过程中烤烟质量形成和温湿度场的时空耦合关系,采用传感器实时监测烤房不同位点的温湿度,构建温、湿度场云图,分析主要化学成分变化,并基于层次分析法对烤后烟叶质量进行综合评价,揭示箱式烘烤过程中温、湿度场与箱体内烤烟质量形成的关系。结果表明,箱体内不同层面的温度分布呈现下层温度最高,中层次之,上层最低。随着烘烤进程的推进,箱体内部各层面高温区的分布模式呈现从四周向中心聚集的趋势;箱体内不同层面湿空气由箱体中层向箱体上层移动,从定色前期至干筋期,在箱体内上层面逐渐形成相对高湿环境,箱体内同一层面湿空气的分布遵循中心高四周低的规律。箱式烘烤过程中,箱体下层较中、上层温度高且湿度偏低,淀粉降解量大,烘烤结束时烟叶淀粉含量降为3.88%;总糖和还原糖含量显著低于其他层面;蛋白质降解速率快;总氮含量总体变化平缓;香气物质积累量大,为1 308μg/g。箱式烘烤箱体内不同层面烟叶烤后质量评价结果显示,下层烤烟综合评分为0.817,中层烤烟为0.765,上层烤烟为0.721,箱体下层的烤后烟叶质量最优。以上结果表明,位于箱体下层烟叶环境温度高、相对湿度低,其淀粉降解量大,香气物质及总糖和还原糖转化积累量高,烤后烟品质优。

增施微藻和牛粪有机肥对土壤化学性质和细菌群落以及烤烟产质量的影响

【目的】研究增施微藻和牛粪有机肥对烟草生长、产质量及土壤细菌群落的影响。【方法】设置微藻、牛粪有机肥、微藻+牛粪有机肥和空白对照(CK)4个田间试验处理,监测烟株农艺性状、烤后烟叶产量和化学成分,测定土壤化学性质,运用荧光定量PCR、Illumina Miseq测序等分子生物学技术分析土壤细菌群落丰度和组成。【结果】与CK相比,增施微藻+牛粪有机肥可显著增加土壤硝态氮、溶解性有机碳、有效磷和速效钾含量,改善土壤pH;烟株圆顶期株高和叶数显著增加,烤后烟叶中总氮、钾、烟碱、总糖和还原糖含量以及氮碱比和钾氯比显著增加,烟叶产量和产值分别提高13.70%和16.78%;可提高土壤细菌群落多样性,优化土壤细菌群落结构,其中芽孢杆菌属(Bacillus)的相对丰度升高,提升了土壤细菌群落抑制青枯病害的能力。典型对应分析结果表明:土壤pH以及硝态氮和速效钾含量是影响土壤细菌群落结构组成的关键因素。【结论】增施微藻和牛粪有机肥可提高土壤养分含量,活化土壤有益微生物,提高细菌群落抑制青枯病菌的能力,改善土壤微生态环境,促进烟草生长,提高烟叶产量和品质。

云南师宗烟区土壤养分与烟叶化学成分研究

为探明云南师宗烟区植烟土壤养分以及烟叶化学品质指标的含量状况,为其烤烟生产合理布局和科学精准施肥提供依据。采集师宗县7个乡镇地区土壤样品和烟叶样品分别110份,分析其土壤养分和烟叶品质,并进行了评价。结果表明,该地区随海拔升高,土壤pH和有效钙降低,海拔对其他土壤养分和烟叶品质无显著影响。师宗烟区土壤pH整体适宜烟株生长,60%处于最适宜范围;土壤有机质92.7%属于“高”和“极高”范围。大量元素总氮总体含量85.5%属于“高”和“极高”范围,碱解氮含量大部分中等(63.9%),23.1%属“极高”范围,13%含量“低”;全磷和全钾缺乏,处于“低”和“极低”范围,分别占71.8%和90.7%;但速效磷和速效钾占“中等”及以上的比例达98.2%和78.1%。中微量元素整体含量较高,但有效硫和有效钼含量分别有29.6%和25.9%处于“低”和“极低”水平,有效钙和有效镁100%处于“高”及以上水平,有效铜、有效铁、有效锰和水溶性氯含量丰富;烟叶含糖量较高,其他基本符合优质烟叶的标准。该地区应注意钾、硫肥的施用,减少钙和镁投入。

基于感官品质与常规化学成分的加热卷烟用烟叶原料评价

为提升加热卷烟产品品质及稳定性,提出一种基于感官品质与常规化学成分的加热卷烟用烟叶原料评价方法。首先计算烟叶原料与基准样品感官品质的相似度,其次采用灰色关联法分析烟叶原料常规化学成分与感官品质的关联关系,再次基于隶属度模糊综合评判评价烟叶原料的适宜性,最后通过重复性实验和分类实验验证该方法的一致性和准确性。结果表明:总氮、烟碱与感官评价各指标的关联度相对较大,两糖差与感官评价各指标的关联度相对较低,可将总氮、烟碱作为加热卷烟烟叶原料评价时的主要关注指标;该评价方法可将22种烟叶原料样品划分为加热卷烟导向型烟叶模块、辅助型烟叶模块和主体型烟叶模块,且其一致性较好、分类较准确,能够应用于配方设计及维护。

采收成熟度对雪茄茄衣烟叶晾制质量的影响

为探讨雪茄茄衣烟叶适宜采收成熟度,研究了不同采收成熟度对茄衣中部烟叶主要农艺性状及晾制后物理指标、化学成分及外观质量的影响。结果表明,随着采收成熟度的提高,鲜烟叶SPAD值和含水率降低,色度值升高;晾制后烟叶叶片厚度、叶面密度和拉力值先升高后降低;两糖比先增加后降低,氮碱比和钾氯比降低;成熟度和油分得分升高,支脉粗细和支脉平伏度得分降低。综合考虑物理特性、化学成分和外观质量,茄衣中部烟叶适宜采收成熟度的外观特征为叶色绿黄(绿中微带黄),主脉1/3变白,支脉1/4变白,茸毛少部分脱落。

雪茄茄芯和茄衣烟叶不同区段化学成分和品质差异性分析

为明确雪茄烟叶不同区段的品质差异,以雪茄品种德雪1号发酵后分拣出的一等茄衣和茄芯烟叶为材料,对叶基至叶尖5个不同区段的常规化学成分、中性香气成分、烟草特有亚硝胺(TSNAs)及前体物含量进行测定,并进行感官评吸鉴定。结果表明,雪茄烟叶不同区段化学成分差异显著,还原糖、总糖含量在叶尖和近叶尖区段相对较高,总氮和蛋白质含量在近叶基区段较高,烟碱含量自叶基到叶尖先升高后降低。茄芯、茄衣烟叶的中性香气成分含量从叶基至叶尖均先增加后减少,其中茄芯烟叶在叶中区段最高,茄衣在近叶基区段最高。2种类型雪茄烟叶的TSNAs含量从叶基至叶尖均持续下降,但降幅不同,茄芯、茄衣烟叶叶尖较叶基分别下降68.25%、30.19%。除刺激性外,2种烟叶的6项感官质量指标得分及总分从叶基至叶尖均表现为先升高后降低,以叶中和近叶尖区段较优。综上,雪茄烟叶以叶中和近叶尖区段香气浓郁,有害成分低,评吸质量较好。

主成分分析法在山东上部烟质量评价中的应用

本研究旨在运用主成分分析法对山东地区上部烟叶的质量进行综合评价,以便为该地区烤烟质量的准确评估提供科学依据。研究以山东10个主要植烟县2020年和2021年间105份B2F等级烟叶样品为材料,通过应用标准化法和主成分分析法对这些烟叶样品的物理特性和化学成分指标进行归类处理,并对各植烟县样品的上部烟叶质量进行分类。研究发现,单叶重与叶长和叶宽、叶片密度与叶片厚度、总糖与还原糖、烟碱与氮间极显著正相关,且主成分特征向量一致,可分别归为一类指标。根据物理特性评价结果,可将山东产区上部烟分为三类,根据化学成分评价结果,可将山东产区上部烟分为两类。综合考虑物理特性和化学成分评价结果,山东产区上部烟叶可分为四类。其中沂源、五莲、临朐为一类,兰陵、沂水、莒县、莱芜为一类,淄川、黄岛为一类,诸城则单独构成一类。

雪茄烟叶烟灰白度与其常规化学成分之间的相关性研究

[目的]研究雪茄烟叶中常规化学成分与烟灰白度的关系。[方法]对国内外77个雪茄烟样的总糖、还原糖、总氮、烟碱、钾、氯含量及其烟灰白度进行测试,并应用相关性分析和逐步回归分析方法进行分析。[结果]国内外不同产区雪茄烟叶常规化学成分与烟灰白度差异明显,雪茄烟叶烟灰白度与烟叶中的钾和总糖含量呈极显著负相关,与烟叶中烟碱含量呈显著负相关。[结论]该研究对提高雪茄燃烧质量和烟灰白度具有一定参考意义。

烟秆生物质炭基肥施用对烤烟产质量的影响

为探讨烟秆生物质炭基肥施用对烤烟产质量及病害发生的影响,以烤烟品种‘红花大金元’、‘K326’、‘云烟87’为研究对象,设置1个常规施肥处理(CK)和3个烟秆生物质炭基肥不同施用量处理(T1为400 g/株,T2为500 g/株,T3为600 g/株),测定不同品种及处理下的烤烟生育期、农艺性状、发病率、经济性状、化学成分。结果表明:(1)与对照处理相比,施入烟秆生物质炭基肥均能延长烤烟‘红花大金元’、‘K326’、‘云烟87’的各生育期,且能显著提高烤烟的株高、茎围、有效叶片数、最大叶长和叶宽,其中‘红花大金元’的施用量为600 g/株、‘K326’和‘云烟87’的施用量为500 g/株时对烟株生长发育促进效果最佳。(2)施用烟秆生物质炭基肥处理的烟草花叶病、野火病和气候性斑点病发病率显著低于对照处理,其中‘红花大金元’和‘K326’的施用量为600 g/株、‘云烟87’的施用量为500 g/株时烟株病害发生率最低。(3)施用烟秆生物质炭基肥处理的烟草产量、均价、中上等烟比例和产值显著高于对照处理,其中‘红花大金元’的施用量为600 g/株、‘K326’和‘云烟87’的施用量为500 g/株时对提高烟株产质量促进效果最佳。(4)施用烟秆生物质炭基肥处理后,‘红花大金元’能显著降低烟叶总糖、还原糖含量,并且使得烟叶总氮、氧化钾和水溶性氯含量更适宜,‘K326’和‘云烟87’能使烟叶总糖、还原糖、总氮、烟碱、氧化钾和水溶性氯含量显著趋于适宜范围,其中‘红花大金元’的施用量为600 g/株、‘K326’和‘云烟87’的施用量为500 g/株时烟株烟叶化学成分含量最适宜。综上,‘红花大金元’施用600 g/株、‘K326’和‘云烟87’施用500 g/株的烟杆生物质炭基肥对烟株生长效果最佳。

醇化烟叶关键微生物类群与风格特色的相关性

分别选取清香型(云南玉溪)、浓香型(湖南郴州)和中间香型(贵州遵义)醇化1年的C2F烟叶,测定烟叶的主要化学成分;利用相似度检验分析烟叶微生物群落差异物种,随机矩阵理论构建分子生态网络;运用Mantel分析烟叶主要化学成分与微生物群落的相关性,结果表明:清香型、中间香型和浓香型烟叶微生物群落结构存在显著差异,浓香型烟叶细菌及真菌群落ɑ多样性指数最高;烟叶显著富集的关键细菌类群为假单胞菌属(Pseudomonas)、肠杆菌属(Enterobacter)和鞘氨醇单胞菌属(Sphingomonas);关键真菌类群为链格孢属(Alternaria)、根霉菌属(Rhizopus)和桑帕约氏酵母菌属(Sampaiozyma);以浓香型烟叶微生物分子生态网络规模最大,结构复杂且相对稳定。总糖与还原糖含量显著影响烟叶微生物群落的多样性与结构,清香型及中间香型烟叶内关键微生物类群均与总糖、还原糖含量呈显著正相关,而浓香型烟叶关键微生物类群均与总糖、还原糖含量呈显著负相关。

不同醇化时间片烟原料化学成分特点与差异分析

烟叶醇化是去除烟叶青杂气、改善烟叶吸食品质的重要环节之一。为研究不同醇化时间对片烟常规化学成分含量及化学成分协调性的影响,本研究以醇化0、12、24、36个月的B3F片烟作为试验材料,将烟叶烘干打碎过筛后进行化学成分的测定,采用显著性方差分析研究不同醇化时间片烟原料质量成分及各种化学指标的比值之间的差异,从中选取最佳醇化时间的片烟,并筛选出关键醇化质量指标。结果表明:不同醇化时间的片烟原料成分之间存在差异,其中总氮、总植物碱、还原糖、总糖、钾含量存在差异,氯、淀粉含量不存在差异;随着时间的延长,总植物碱、总氮的含量先增加后减少再增加,还原糖、总糖的含量先减少后增加,钾含量逐渐增加,氯和淀粉含量变化幅度不大。总体而言,醇化12个月的片烟与醇化0、24、36个月的片烟的质量成分数值差异较大。另外,结合我国优质烟叶化学成分指标,就片烟原料化学质量特点来看,本研究中醇化时间24个月左右的烟叶品质最佳。