固态发酵生产腺苷酸脱氨酶

对多株曲霉产腺苷酸脱氨酶的性能进行了比较,发现米曲霉3.800(Aspergillus oryzae)产酶水平较高。该菌株固态发酵产酶的适宜培养基为：以麸皮为主原料,蔗糖2％,鱼粉2％,（NH4）2SO4 0．1％,柠檬酸钠0．2％,MgSO4 0.05%,吐温－80 0．1％,含水量50％。最佳的培养条件为：250mL三角瓶装20g培养基,在28－30℃培养60h。在优化条件下,培养物酶活可达到1543．48u/g鲜曲。     

产环氧化物水解酶的黑曲霉菌种分离和发酵条件的研究

从土壤中筛选出一株能将苯基环氧乙烷立体选择性水解为R－苯基乙二醇的环氧化物水解酶的黑曲霉SQ－6。对其产酶发酵条件进行了研究,最佳碳,氮源分别为2．0％蔗糖和2．0％玉米浆,最适初始pH为4．0,该酶不需诱导,同时还研究了其他发酵条件对产酶的影响,使用含酶细胞进行底物苯基环氧乙烷转化。产物（R）－苯基乙二醇转化率为41％,ee值为99％。     

CN—92植酸酶产生菌的诱变选育及产酶条件的研究

以无花果曲霉IFFI2227为出发菌株,通过NTGT和Co60复合诱变处理,获得5株产植酸酶活力比出发菌株高2．1～2．5倍的高产菌株。其中1株CN－92菌产酶性能稳定,研究了该菌株的最适产酶条件：培养温度30℃,培养基起始pH6．0培养时间72h。适宜于该菌株产植酸酶的优良固体培养基组成为：麸皮、豆饼粉、硫酸铵及少量无机磷,培养基含水率51％。葡萄糖、乳糖和MH4Cl、NH4NO3等不同程度地抑制植酸酶的合成,微量元素如Mn,Zn,Cu等对产酶无促进作用。     

产低温脂肪酶非极端细菌的筛选、产酶发酵及粗酶性质研究

目的：筛选产低温脂肪酶非极端细菌菌株,扩大脂肪酶的应用范围。方法：利用维多利亚蓝B平板显色法和摇瓶发酵法,从土壤中筛选产脂肪酶菌株,通过菌落形态和菌体特征观察初步对菌种进行鉴定,并对该菌株的产酶发酵培养基进行了优化。结果：得到一株产低温脂肪酶非极端细菌菌株sybc—li一1,该菌株适宜产酶培养基（％）为淀粉1、牛肉浸膏1、NaNO3 0．08、CaCl2 0．04、MgSO4 0．04、橄榄油2和OP1;初始DH8、30℃、200r／min培养72h,脂肪酶活力可高达到30．2U／mL;所产脂肪酶粗酶最适作用温度20℃,最适pH9．5,0℃时仍能保持70％的酶活性,属于低温酶;该酶与目前报道的低温脂肪酶相比,有较好的热稳定性,粗酶在pH8．5、70℃条件下保温60mla,酶活力损失30％。结论：该菌株为自然环境中筛选的非极端细菌,所产脂肪酶为低温脂肪酶,在开发应用上有良好的前景。     

微生物酶拆分方法生产D-泛酸的手性中间体D-泛解酸内酯

筛选到一株产D－泛解酸内酯水解酶的串珠镰孢霉菌（Fusarium moniliforme SW-902)。产酶条件研究表明,用甘油作碳源,蛋白胨作氮源,初始pH8.0,温度26℃,摇瓶培养3d,产酶量最高。在60L和1000L发酵罐中通风发酵45－47h,产酶量为6－8g干菌体／L,D－泛解酸内酯水解酶酶活力达到0．87－0．92IU／g干菌体。该酶的最适反应温度为55℃,最适反应pH为7．0－7．5。在酶不对称水解泛解酸内酯过程中,对溶液加酶量5％－10％,底物浓度10％－20％,控制水解率20％－30％,水解效果最好。     

嗜碱芽孢杆菌NTT33产碱性β-甘露聚糖酶发酵条件的研究及高产菌株选育

研究了嗜碱芽孢杆菌（ａｌｋａｌｏｐｈｉｌｉｃＢａｃｌｕｓｓｐ．）ＮＴＴ３３发酵产生胞外碱性β－甘露聚糖酶的条件,其最佳碳源为１％槐豆角,最佳氮源为１％蛋白胨＋０．２％酵母膏,发酵培养３６ｈ产酶量最高（达６１．３υ／ｍＬ）。甘油,葡萄糖,甘露糖等对产酶有强的阻遏作用。该菌株经紫外诱变处理后,采用透明圈法初步筛选出在含葡萄糖和不含葡萄糖的槐豆胶培养基上同时产生透明圈的菌株,进一步测定其产酶进程曲线,最后筛选到一株（ＮＴＴ３３－ｒ６）部分消除葡萄糖代谢阻遏高产β－甘露聚糖酶的菌株,其酶活力比出发菌株提高５０％,,达到９６．３Ｕ／ｍｌ;。     

白腐真菌AH28-2菌株发酵合成漆酶初步研究

从224个野外采集的真菌样品中筛选分离到一株产漆酶活性较高菌株AH28－2,经初步鉴定为白腐真菌,采用单因子相互比较法,研究了该菌株最适发酵产酶条件。应用添加有1g／LKraft木素的液体发酵培养基,接种量5％（V／V）,初始pH8．5,装液量为50％,28℃、150r/min摇瓶振荡培养4－5d,漆酶酶活水平达20184IU／L。     

高产超氧化物歧化酶菌株发酵条件的研究

从1348株芽孢杆菌(Bacillus cereus)中分离和选育出高产超氧化物歧化酶(superoxide dismutase)菌株C328,并进行了产酶条件的研究。结果表明,该菌株最佳产酶的最适温度为30～35℃,培养基最适起始pH为8．0～8．5。金属离子Cd^2 、Mn^2 、Zn^2 ,表面活性剂吐温80、司班80、琥珀酸钠和无机盐CaCl2、CaCO3对产酶有抑制作用。适宜浓度的K2HPO4、EDTA、金属离子Fe^3 和表面活性剂NaAC对产酶有明显的促进作用。发酵培养用250mL三角瓶以30mL装液量酶活力最高。适宜种龄为8～12h,适宜接种量为0．9％～3％,最佳接种量为1％～2％。     

碱性普鲁兰酶产生菌选育和发酵条件的研究

从儿童食品中分离筛选到1株产碱性普鲁兰酶活性较高的菌株,编号为SX－12,初步鉴定为芽孢杆菌Bacillus sp.,研究了SX－12原生质体制备与再生最佳条件,其原生质体经紫外线诱变处理,选育出产碱性普鲁兰酶的高产菌株SX－12C67,酶活由出发菌株的2．42U/mL提高到6．87U／mL,提高了约1．8倍,在此基础上对产酶条件进行了优化,优化后的最佳发酵培养基为：可溶性淀粉3％,蛋白胨1．0％,酵母膏0．5％,K2HPO42％,MgSO4.7H2O0.05%MnCl20.0001%,最适p;H9.5,最适温度40℃,初步研究了酶的部分性质,酶反应的最适pH,温度分别为10．0－10．5和55℃,在55摄氏度反应条件下,酶在pH6.0-11.0的范围内都具有一定的活性,Ca^2 ,Mn^2 ,Mg^2 等离子是酶的激活性,Zn^2 ,Hg^2 等离子是抑制剂。     

嗜碱芽孢杆菌XE22-4-1碱性弹性蛋白酶发酵条件的研究

从西藏天然碱湖中筛选到一株产碱性弹性蛋白酶 (alkalineelastase)菌株 ,最适生长pH为 1 0 0 ,经鉴定为Bacillussp .,编号XE2 2 4 1。该菌产酶最适碳源为 2 %葡萄糖 ,氮源为0 2 5%酵母粉 ,豆饼粉对发酵产酶有促进作用。 2L发酵罐实验表明 ,溶解氧是影响该菌株产酶的重要因素。通过提高通气量和改变搅拌速度 ,该菌株可在发酵 48h内达到产酶高峰 ,酶活力最高达 2 66u mL     

L-山梨糖流加发酵高效生产2-酮基-L-古龙酸

实验充分利用混合菌系氧化葡萄糖酸杆菌(Gluconobacter oxydans)和蜡状芽孢杆菌(Bacillus cereus)混合发酵的优良特性,通过在发酵过程中间歇流加L-山梨糖的方法,实现了在自动控制温度、pH和溶氧的条件下,高效发酵L-山梨糖生成2-酮基-L-古龙酸(2-KLG)的目的。结果表明：当将L-山梨糖的终浓度调高到14％(w／v)时,2-KLG产量为130mg／mL左右,转化率达90％,发酵周期40—60h之间。结论：发酵过程中间歇流加L-山梨糖可以解除高浓度糖对产酸的抑制作用,提高了糖的转化率,但是发酵周期略有延长。     

产弹性蛋白酶细菌的发酵动力学研究

基于14L的发酵罐分批发酵实验数据,建立了发酵过程菌体生长、产物生成及基质消耗随时间变化的数学模型。Logistic方程、Luedeking—Piret方程能够很好地分别描述产弹性蛋白酶菌体生长;发酵产酶过程和基质消耗过程。并将3个动力学模型的预测值和实验值进行了比较,所建立的分批发酵动力学模型能较好地反映弹性蛋白酶分批发酵过程。     

菊糖芽孢乳杆菌DS2-18中试规模的D-乳酸发酵研究

研究了菊糖芽孢乳杆茵DS2的突变株DS2-18在中试规模的D-乳酸发酵.在容积为300L自控发酵罐中,DS2-18茵在合适的发酵条件下,即培养基组成(g/L):葡萄糖120,玉米浆8,蛋白胨6,豆粕水解液100,接种量8%(v/v),发酵温度40℃,以轻质碳酸钙作为中和剂调pH 5～6,发酵期间交替不通气和通气,发酵6...     

抗菌活性海洋真菌HN4-13的鉴定及其发酵优化

[目的]鉴定一株来源于连云港近岸海域沉积物并具有分泌抗菌活性代谢产物的真菌菌株HN4-13,优化其合成抗菌活性物质的发酵条件.[方法]通过形态学观察及ITS序列分析方法对菌株HN4-13进行鉴定;通过基础发酵培养基筛选、碳氮源及无机盐的单因素试验,继而采用正交试验设计优化其合成抗菌活性物质的发酵条件.[结果]菌株HN4-13被鉴定为黄柄曲霉(Aspergillus flavipes),其分泌抗菌活性产物的发酵条件为:4％蔗糖、0.5％蛋白胨、0.1％ KCl、0.06％ NaH2PO4、28℃、1％接种量、160 r/min培养9d.[结论]实验结果为进一步分离纯化菌株HN4-13所产抗菌活性代谢产物提供了基础.     

Bioconversion of grape must into modulated gluconic acid production by Aspergillus niger ORS-4.410

AIMS: Analysis of regulators for modulated gluconic acid production under surface fermentation (SF) condition using grape must as the cheap carbohydrate source, by mutant Aspergillus niger ORS-4.410. Replacement of conventional fermentation condition by solid-state surface fermentation (SSF) for semi-continuous production of gluconic acid by pseudo-immobilization of A. niger ORS-4.410. METHODS AND RESULTS: Grape must after rectification was utilized for gluconic acid production in batch fermentation in SF and SSF processes using mutant strain of A. niger ORS-4.410. Use of rectified grape must led to the improved levels of gluconic acid production (80-85 g l(-1)) in the fermentation medium containing 0.075% (NH4)2HPO4; 0.1% KH2PO4 and 0.015% MgSO4.7H2O at an initial pH 6.6 (+/-0.1) under surface fermentation. Gluconic acid production was modulated by incorporating the 2% soybean oil, 2% starch and 1% H2O2 in fermentation medium at continuously high aeration rate (2.0 l min(-1)). Interestingly, 95.8% yield of gluconic acid was obtained when A. niger ORS-4.410 was pseudo-immobilized on cellulose fibres (bagasse) under SSF. Four consecutive fermentation cycles were achieved with a conversion rate of 0.752-0.804 g g(-1) of substrate into gluconic acid under SSF. CONCLUSIONS: Use of additives modulated the gluconic acid production under SF condition. Semi-continuous production of gluconic acid was achieved with pseudo-immobilized mycelia of A. niger ORS-4.410 having a promising yield (95.8%) under SSF condition. SIGNIFICANCE AND IMPACT OF THE STUDY: The bioconversion of grape must into modulated gluconic acid production under SSF conditions can further be employed in fermentation industries by replacing the conventional carbohydrate sources and expensive, energy consuming fermentation processes.     

解淀粉芽孢杆菌3-2发酵羽毛产氨基酸

【目的】建立废弃羽毛液体发酵工艺,优化发酵条件,提高羽毛降解率及氨基酸产量,研发新型、高效复合氨基酸肥料。【方法】利用解淀粉芽孢杆菌3-2发酵羽毛,探究温度、发酵时间、羽毛含量、单一碳源、复合碳氮源、金属离子等对废弃羽毛降解效果以及发酵液中氨基酸种类和含量的影响。【结果】废弃羽毛降解率与氨基酸总产量呈负相关。随着发酵时间延长,羽毛降解率增加,当发酵温度为37°C、羽毛添加量为1%、以乳糖为外加碳源、添加Mg2+时,羽毛降解率最高,达到81.92%。随着羽毛添加量增加,氨基酸总含量也增加(在20%范围以内),当发酵温度为37°C、降解时间为108 h、羽毛添加量为10%、乳糖添加量为0.5%、不添加复合碳氮源、不添加金属离子时,氨基酸的种类最全(富含17种氨基酸),总含量最高,达到20.861 g/kg。【结论】利用解淀粉芽孢杆菌3-2发酵废弃羽毛生产氨基酸复合肥料是一种可靠、环保、经济的方法,获得的氨基酸肥料营养齐全。研究结果为新型复合氨基酸肥料的研发提供技术支撑。     

Effects of nutrients on the production of AK-111-81 macrolide antibiotic by Streptomyces hygroscopicus

The influence of different carbon and nitrogen sources on the production of AK-111-81 nonpolyenic macrolide antibiotic by Streptomyces hygroscopicus 111-81 was studied. Substitution of glucose with lactose or glycerol significantly affected maximal antibiotic AK-111-81 productivity as the growth rate was close to that of the basal fermentation medium. Addition of ammonium succinate to the fermentation medium markedly increased the antibiotic productivity as the growth rate was low. Divalent ions as Mn2+, Cu2+, Fe2+ stimulated AK-111-81 antibiotic biosynthesis. These results allow us to develop a new fermentation medium showing 6-fold increase of AK-111-81 antibiotic formation compared with the basal fermentation medium.     

Inhibitory effects of Mannich bases of heterocyclic chalcones on NO production by activated RAW 264.7 macrophages and superoxide anion generation and elastase release by activated human neutrophils

Some chalcones exert potent anti-inflammatory activities. Mannich bases of heterocyclic chalcones inhibited nitric oxide (NO) production in lipopolysaccharide and interferon-γ stimulated RAW 264.7 macrophages. Also Formyl-Met-Leu-Phe and cytochalasin B induced superoxide anion generation (O2·-) and elastase release in human neutrophils. Mannich bases of heterocyclic chalcone analogs exhibited potent inhibitory effects on NO production with IC(50) values ranges between 10.5 and 0.018 μM, O2·- generation (IC(50) 39.87-0.68 μM) and elastase release (IC(50) 39.74-0.95 μM). Compound 29 (IC(50) 0.055 μM) and 34 (IC(50) 0.018 μM) were showed excellent inhibition on NO production. On the other hand, compounds 2 and 8 showed potent inhibition on O2·- generation and elastase release. Therefore, these four compounds may be new leads for development of anti-inflammatory activities. The structure-activity relationships are also discussed.     

假丝酵母99-125脂肪酶的发酵工艺研究

对假丝酵母99-125脂肪酶的发酵工艺条件进行了一系列研究。选择了合适的培养基成分并进行优化 ,获得了最优的摇瓶培养基配方 (% ,W/V) :豆油 4.0 ,全脂豆粉 4.0 ,K₂HPO₄0.1,KH₂PO₄ 0.1。产酶水平能达到 5000IU/mL。在 30L发酵罐上进行初步放大实验 ,其产酶水平能达到 8100IU/mL。在1m³发酵罐上进行中试放大 ,产酶水平可达到 8000IU/mL。     

Production of lactic acid with loofa sponge immobilized Rhizopus oryzae RBU2-10

Lactic acid production by Rhizopus oryzae RBU2-10 immobilized in loofa sponge was evaluated. Shape and texture of loofa sponge, which was obtained from the mature dried fruit of Luffa cylindrica, remained intact after its treatment with buffers of varying pH and following its repeated autoclaving for up to four cycles (121 degrees C, 20 min per cycle). The medium having four pieces of loofa sponge (1.008 cm(3)) per 100 ml medium and inoculated with 3 x1 0(6) spores ml(-1) resulted maximum production (80.75 g l(-1)) of lactic acid in 48 h of fermentation. Repeated batch fermentation for lactic acid production could be carried out for 10 cycles. Remarkably higher levels of productivity (1.66-1.84 g l(-1)h(-1)) was obtained during first five cycles of fermentation with a maximum productivity (1.84 g l(-1)h(-1)) obtained during third cycle of fermentation.