地衣芽胞杆菌ACCC 01957产芽胞碳源组合研究

地衣芽胞杆菌(Bacillus licheniformis)是微生物发酵饲料常用菌。本研究旨在通过优化发酵过程中最重要的碳源因子来提高地衣芽胞杆菌菌株ACCC 01957的菌体量和芽胞产量。首先基于ACCC 01957对Biolog GenⅢ 板的71种碳源进行利用效率筛选,再采用全自动细胞生长曲线仪分析优势碳源对生物量、生长周期及产孢率的影响,并在摇瓶水平上确定最佳发酵碳源。结果表明,菌株ACCC 01957可以较好地利用25种碳源,其中N-乙酰-β-D-甘露糖胺、D-半乳糖、L-鼠李糖、肌苷、甘油、果胶、L-乳酸、吐温-40、L-天冬氨酸、L-谷氨酸和L-焦谷氨酸可以促进其生长和产孢,而D-山梨醇促生长抑产孢;在摇瓶水平上以葡萄糖和L-鼠李糖为复合碳源(添加比例为16)时,培养24 h的菌体总量为8.3×10^(8) cfu/mL,培养48 h的产孢产率高达91.19%。通过产芽胞碳源组合构建提高了地衣芽胞杆菌ACCC 01957的生长、产芽胞率和产芽胞量。

日本无刺楤木离体茎段人工促成产芽技术

在自行研制的人工气候室内,以日本无刺楤木(Aralia elatavar.inermis)休眠枝条离体茎段为试验材料进行了水培人工促成产芽实验。结果表明:不同的茎段长度处理,以20 cm茎段产芽最好,差异极显著;不同的遮光处理,以遮光处理为好,但差异不明显;不同的营养条件处理,以50 mL水+50 mL全成分营养液处理最佳,但与100 mL全成分营养液无显著差异;不同的直径茎段处理,以最粗直径(平均直径12.3 mm)最佳,与最细直径之间差异极显著;不同的树龄相同直径处理,以2年生的产芽量最大,但差异不显著;同一茎段不同的芽位处理,以两侧芽产芽较好,但无显著性差异。

青贮用黄曲霉毒素降解菌株的产芽胞条件优化

[目的]利用正交试验设计对青贮用黄曲霉毒素降解菌株N-1a产芽胞条件进行优化。[方法]以菌株的菌体生物量和芽胞形成率作为考察指标,利用单因素试验和正交试验设计优化菌株N-1a的发酵用培养基组成和培养条件。[结果]优化后的N-1a最佳产芽胞培养基组成配比为:玉米粉2.0%,黄豆饼粉1.0%,MnSO_4·H_2O 0.10%,MgSO_4·5H_2O 0.01%;最佳产芽胞条件为:p H值为7.0,发酵时间48 h,接种量4%,装液量75 m L/250 m L培养基;在该条件下,N-1a的菌体生物量为6.08×10~8cfu/m L,芽胞形成率为81.25%。[结论]菌株N-1a的摇瓶产芽胞条件为其中试生产提供了实验依据。

藏绵羊瘤胃中产纤维素酶芽胞杆菌的分离鉴定

2013年10月,采集10份四川阿坝藏族羌族自治州若尔盖藏绵羊瘤胃内容物。采用高温水浴,富集培养的方法进行芽胞杆菌的分离,并使用刚果红染色法进行产纤维素酶芽胞杆菌的初步筛选,共获得101株产纤维素酶芽胞杆菌。通过16SrRNA序列测定对分离出的芽胞杆菌鉴定出3种不同的芽胞杆菌,其中短小芽胞杆菌78株、蜡样芽胞杆菌14株、枯草芽胞杆菌9株。本研究鉴定了藏绵羊瘤胃中芽胞杆菌的组成,为进一步利用芽胞杆菌开发藏绵羊源的益生菌奠定了基础。

阿维拉霉素对肉鸡盲肠产气梭状芽胞杆菌的数量及生长性能的作用

近年来,世界上所有大型养殖场的兽医师都曾面临到这样一种困扰,十几日到二十多日龄期间,鸡群会出现生长抑制,下痢,死亡率高等疾病,其中以春夏以及季节交接期为甚.人们用各种名字来描述它:"夏季肠炎","饲料便","肉鸡高墙症","水痢","鸡只肠道菌群紊乱","鸡只肠道菌群异常增生 "等,究竟什么是它的诱发原因,如何防治该疾病呢 ?

兔产气荚膜芽胞杆菌病

1999年 4月 ,重庆某兔场突然暴发了一场拉稀病 ,其特征为泻下大量水样或血样粪便和脱水死亡。此病发生迅速 ,绝大多数病兔出现严重的腹泻或水泻 ,一般在 2 4小时内死亡 ,仅几天死亡 40多只兔子 ,并且死亡的兔子均为体格强壮成年兔。经剖检发现均有胃糜烂穿孔 ,食糜进入腹腔 ,肠壁薄而透明 ,大肠粘膜有鲜红出血斑 ,肝肿大 ,胆囊胆汁充盈 ,脾呈深褐色 ,确诊为产气荚膜芽胞杆菌引起的产气荚膜芽胞杆菌病。

基于环介导等温扩增技术的产呕吐毒素蜡样芽胞杆菌特异性检测

本研究旨在建立食品中产呕吐毒素蜡样芽胞杆菌的快速检测方法。基于产呕吐毒素蜡样芽胞杆菌合成酶基因cesB靶基因,设计4条特异性引物(2条内引物、2条外引物),建立环介导等温扩增技术(LAMP)。然后采用2株产呕吐毒素蜡样芽胞杆菌、19株蜡样芽胞杆菌和41株非蜡样芽胞杆菌验证了该LAMP具有很好的特异性。LAMP检测的灵敏度在DNA水平上达到1.49 pg/μL,纯菌的灵敏度为5×10~3 cfu/mL。人工污染米饭样品,当起始污染量为2 cfu/g时,37℃增菌培养6 h,用试剂盒法和煮沸法提取的DNA,都可以检出产呕吐毒素蜡样芽胞杆菌。采用此LAMP方法进行了72份实际样品的检测,检出2份产呕吐毒素蜡样芽胞杆菌阳性样品,与传统方法一致。因此,本研究建立的LAMP检测方法可应用于食品中产呕吐毒素蜡样芽胞杆菌的快速特异检测。

楸树嫩芽扦插繁育技术研究

为加快楸树繁育推广,采用安徽省林业科学研究院提供的"8611"和"4002"优良品种,开展了楸树芽插繁育试验。经试验发现,温棚催芽产芽量是自然萌芽量的3.38倍,双层温棚扦插成活率较高,温棚温度应控制在25～35℃条件下,30 d可生根成活,幼苗生长正常;4月上中旬是楸树出芽的高峰期,也是揪树嫩芽扦插的最佳时期;营养土应在扦插当天消毒效果最好;经调查分析,两品种芽插苗大田定植后地径、高度生长无明显差别。

南海冷泉区深海沉积物中细菌的分离培养及多样性分析

为了认识南海深海冷泉区沉积物中可培养微生物的多样性,本文以冷泉区与非冷泉区两个站点的深海沉积物为样品,通过两种培养基(R2A海水培养基和2216E培养基)直接涂布或富集后平板分离纯化,从9个样品中共得到395株菌株,并通过16SrRNA基因鉴定,分属10个属。发现产芽胞细菌分布最广、丰度最大,包括3个属、15个种。其中芽胞杆菌(Bacillus)无论是在数量还是在种类上都分布最多。并且,随着水深和沉积物深度的增加,分离到的可培养微生物丰富度降低。本研究表明,即使在冷泉区,南海深海沉积物中产芽胞细菌也比较丰富。

Application Effects of Ultra-fine Powder Shaped Maize Seed Coating Agent in Spring Sowing areas in northeast China

The research explored adaptability maize seed coating agent in spring sowing and effects of ultra-fine powder shaped areas in northeast China. The results showed that germination potential and rate both improved around 5% and the num- ber of root increased by 4% in the treatments with ultra-fine powder shaped maize seed coating agent compared with the control group without seed coating. What＇s more, the treatments with ultra-fine powder shaped maize seed coating agent took advantages in terms of fresh weight of seeding, stem diameter, and dry weight. It is notable that control effects on underground insects performed the best, with per- centage over 94%, which is more excellent relative to other agents in markets. Therefore, ultra-fine powder shaped maize seed coating agent can be widely applied in spring sowing areas in northeast China, without side effects.

Effects of Specific Gravity-based Seed Grading on Seed Germination, Seedling Emergence and Grain Yield of Hybrid Rice

Using the commercial seeds of two hybrid rice varieties including Lu- liangyou 996 and Liangyoupeijiu as the materials, four specific gravity-based seed grading treatments, Le., the specific gravity of 〈1.0 （T1）, 1.0-1.09 （T2）, 1.1-1.19（T3） and ≥1.2 （T4）, by selection with different saline solutions, and the control without seed grading （CK） were designed to study the effects of seed grading on seed germination, seedling emergence, seedling quality and grain yield. The results showed that the treatments of T2, T3 and T4 had higher or significantly higher seed germination rate, germination index and vigor index, seedling emergence rate and adult seedling rate than the CK, while T1 had significantly lower values of these traits than the CK. Compared with the CK, the number of spikelets per pani- cle was found to be the main reason for the yield increase of these treatments with high seed viability.

Development and Age Structure of Ramets of Kalimeris integrifolia Populations in the Songnen Plains, Northeast China

Kalimeris integrifolia Turcz. is a root sucker form perennial herb of Compositae. In die late period of growing season, fresh fleshy radicels grow up above the soil surface to develop root-borne buds, which in turn grow into ramets and taproot. On the basis of observation on numerous samples, methods to classify the age of ramets and buds for the root sucker herbaceous plant population and to estimate the ages of taproots were established according to their morphology. The age of ramets was classified based on the regeneration times of taproot buds. Ramets developed from new root sucker buds were classified as 1 a. After 1 a ramets died, the ramets reproduced from the taproots were 2 a, and so on. New buds from a root sucker were 0 a buds, other age classes of buds were consistent with that of ramets, i.e. buds produced from taproots of I a ramets were 1 a buds, and so on. In the hay clipping meadows of the Songnen Plains, for K. integrifolia population, there are three age classes of ramets, representing a steady age structure. The maximal age of taproots of ramets is 4 a. Among all age classes, the population productivity of 2 a ramets was the highest, and that of I a ramets was the lowest. The ramet productivity increased with ramet age. During the early period of growing season, the productivity of 3 a ramets was the highest, but after the middle of growing season, I a ramets showed the greatest relative growth rate. The population size and age structure in the next year could be accurately forecasted by the number of fresh roots with budlet and present population in late autumn. The potential population in the bud banks was more than two times of the present population, which may provide sufficient substitution in the future.

Isolation of an acid producing Bacillus sp. EEEL02: Potential for bauxite residue neutralization

Bauxite residue deposit area(BRDA)is a typical abandoned mining wasteland representing extreme hostile environment with increased alkalinity.Microbially-driven neutralization of bauxite residue,based on the microbial acid producing metabolisms,is a novel strategy for achieving rapid pH neutralization and thus improving its environmental outcomes.The hypothesis was that these extreme conditions promote microbial communities which are capable of novel ecologically relevant functions.Several alkaliphilic acid producing bacteria were isolated in this study.One strain was selected for its superior growth pattern and acid metabolism(termed EEEL02).Based on the phylogenetic analysis,this strain was identified as Bacillus thuringiensis.The optimized fermentation conditions were as follows:pH 10;NaCl concentration 5%;temperature 25℃;EEEL02 preferred glucose and peptone as carbon and nitrogen sources,respectively.Based on optimal fermentation conditions,EEEL02 induced a significant pH reduction from 10.26 to 5.62 in 5-day incubation test.Acetic acid,propionic acid and CO2(g)were the major acid metabolites of fermentation,suggesting that the pH reduction in bauxite residue may be caused by acid neutralization derived from microbial metabolism.This finding provided the basis of a novel strategy for achieving rapid pH neutralization of bauxite residue.

Continuous Production of Butanol by Bacteria of Genus Clostridium

Performance of continuous 1-butanol production process by Clostridium bacteria is complicated by alternation of acidogenic and solventogenic phases during fermentation what correlates with culture growth and sporulation, respectively. However, the strain Clostridium pasteurianum NRRL B598 showed diverse pattern of solvents production when butanol production started during exponential growth phase in batch cultivation. If cultivated under glucose limited conditions with dilution rate 0.03 hl, constant product concentration was almost achieved. By contrast, glucose non-limited continuous experiment operated with dilution rate 0.07 h-1 lead to mutually adverse oscillations of product and glucose concentrations. Regarding the process economy, glucose limited continuous cultivation seems to be superior due to utilization of total supplied glucose amount, advantageous butanol/acetone ratio and higher butanol yield.

A marked enhancement in production of amylase by Bacillus amyloliquefaciens in flask fermentation using statistical methods

A total of 126 bacterial strains were isolated from soil samples. Among them, 11 isolates were found positive for amylase production. Strain YL produced the largest zone of clearance on plate assay. The isolate YL was identified as Bacillus sp. based on morphological and physiochemical characterization. According to 16S rRNA gene sequencing data, the closest phylogenetic neighbor of strain YL was Bacillus amyloliquefaciens （99.54%）. After that, an optimization of culture conditions was carried out for the improvement of a-amylase production. Response surface methodology （RSM） was applied to evaluate the effect of medium components including wheat bran, cottonseed extract, yeast extract, starch, NaC1 and CaCl2. Three variables （wheat bran, cottonseed extract, and starch）, which were identified to significantly affect amylase production by Plackett-Burman design were further optimized using response surface methodology of Box-Behnken design （BBD）. The optimal concentrations estimated for each variable related to the maximum of amylase activity （86 kU/mL） were 10.80 g/L wheat bran, 9.90 g/L cottonseed extract, 0.5 g/L starch, 2.0 g/L yeast extract, 5.00 g/L NaCl and 2.00 g/L CaC12. The fermentation using optimized culture medium allowed a significant increase in amylase production （by 3-fold）. The improvement in the a-amylase production after optimization process can be considered adequate for large-scale applications.

Can Kponan Yam （Dioscorea cayenensis） Full Season Tuber Sprout If Planted？

In a completely randomized blocks （RCB） plot, we planted seed from the three segments of Kponan tubers： head, median and tail portions with control Krengle. Germination began 10 d and lasted 67 d. The mean sprouting rate of the Kponan full season harvest tuber was 78.1% compared to 94% in Krengle. However, the tuber germination was progressive from head to tail with a linear evolution of the top fragments with sprouting rate up to 90% similar to Krengle. The median and distal portions sprout two and three weeks later with final raising rates reaching 68% and 71%, respectively. The full season tuber of Kponan sprouts with a good rate gave good yields for any portion of the tuber. It had a sprouting gradient oriented from the proximal portion to the distal one, while yield was better for medium seeds. The sprouting delays two weeks between proximal and medium portions and three weeks between proximal and distal portions were acceptable with regards to the total cycle of eight to nine months period. Thus, its small tubers could be planted as well as the top portion of big tuber. In terms of yield, Kponan medium seed gave the best yield 34.25 t/ha and the whole Kponan tuber yield was more than Krengle. That led to a better multiplication factor for Kponan full season tuber. The type of tuber, if available, could be used as seed for yam production. That could improve its distribution and contribute to food security.

Producing Arabic Bread Enriched with Minerals and Protein

This research aims to produce Arabic bread enriched with iron, zinc, copper, magnesium and protein by the addition of ingredients such as parsley powder, oats, grape seeds, soybean meal, wheat germ, and milk powder. In this study, for enriched bread samples sensory evaluation, chemical and mineral composition determination and microbiological tests were carried out. The sensory evaluation of breads showed that both mixtures, which were enriched with grape seeds, oats, and wheat germs, have excellent quality. The chemical tests showed that the enriched breads have high fat, ash, fiber, and protein when compared with normal Arabic bread. It was noticed that the consumption of three enriched Arabic bread loaves gives us about 78.9% from our daily need of zinc, whereas the unenriched bread gives us only 48.8%, about 82.2% from our daily needs of copper, whereas the normal bread gives us only 58.8%, and 93.9% from our daily need of iron, whereas the normal bread gives us only 71.2%.

Effect of Some Bioproducts on Winter Mortality of Grafted Buds and the Number of Maiden Fruit Trees Produced in an Organic Nursery

In an organic nursery, various bioproducts were used to stimulate plant growth： Fertigo （granulated bovine manure）, Micosat, Humus UP （humic acids microbiologically enriched）, Humus Active ＋ Aktywit PM （beneficial microorganisms）, BioFeed Amin, BioFeed Quality, Tytanit, and Vinassa. One of the aims of the study was to determine the effect of these products on the ability of grafted buds of apple and sour cherry cultivars to survive the winter. Losses resulting from the freezing of buds during winter dormancy were calculated as the difference between the number of buds deemed to have taken in autumn and the number of live buds that began to develop properly in the spring of the following year. In autumn, the number of maiden trees obtained in each fertilization combination was also determined in the same nursery. The greatest tendency to die in winter was shown by apple and sour cherry buds in those combinations in which the rootstocks were supplied with a mineral fertilizer with NPK components, and the smallest where humic preparations （so-called vermiculites） were used. The type of fertilizer had an indirect influence not only on the number of grafted buds that died in winter as a result of freezing, but also on the final number of maiden trees obtained from a given area of the nursery.

Comparison of Beer Quality Produced Using Malt from Kosovo and Other Countries

Aiming to optimize the beer production process by improving the properties of beer and reducing production costs at the J.S.C. ＂Birra Peja＂ brewery, Peja, Kosovo, this study did an evaluation of beer produced using six different malts. Four of the six studied malts were produced in four European countries： Ukraine, Croatia, Serbia and Kosovo; and, the other two malts were obtained from two （2） 30：70 proportion mixtures： one from Kosovo and Ukraine and another one from Kosovo and Croatia. Chemical, microbiological, sensory and tasting analyses were carried on beers produced by these malts. The study included three working groups from： ＂Birra Peja＂; the Agricultural University of Tirana, Albania and ＂Union Brewery＂, Ljubljana, Slovenia. Chemical and microbiological tests were based on methods under the EBC （European Beer Convention） and MEBAK （Mitteleurop^iische Brautechnische Analysenkommision e.V.） guidelines. The analyses and assessments made for the quality of beer have come to the conclusion that beer produced by Croatian origin malt corresponds to a better quality beer.