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101.
菌株F3从土壤中筛选得到,具有产生转糖基β-半乳糖苷酶(β-galactosidase) 的特性。根据形态观察及18S rDNA序列分析,菌株F3被鉴定为扩张青霉(Penicillum expansum)。通过单因子试验和正交试验,对菌株F3产生转糖基β-半乳糖苷酶的培养基组成及发酵条件进行了优化。优化后的培养基组成为葡萄糖2%、酵母粉1%、蛋白胨1.5%、氯化钠0.3%。在初始pH 6.0,28?℃培养40?h时,其产酶量为2?245.2?U/L, 比优化前提高约3倍。菌株F3产生的转糖基β 半乳糖苷酶以pH 4.5缓冲液配制的30%乳糖为底物,50?℃反应24?h,低聚半乳糖产量为30.6%,其中80%以上为三糖。
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102.
Lucía del Sol González-Forte Javier I. Amalvy Nora Bertola 《International Journal of Polymer Analysis and Characterization》2019,24(1):63-74
The incorporation of antimicrobials in foods by means of the use of films where they are entrapped collaborates to decrease their diffusion rate. In this work, the physicochemical properties of starch-based films loaded with 1% wt. natamycin were analyzed, and the antifungal activity of these films was evaluated against Penicillium spp..
Variations in the properties of films with 1% natamycin were minimal, leading to the conclusion that this material could be applied to avoid mold development on the surface semi-hard cheeses. Corn starch-based films containing natamycin at 1% w/w inhibited the Penicillium spp. growth in a solid matrix. 相似文献
103.
Costa Silgia A. Pessoa Adalberto Roberto Inês C. 《Applied biochemistry and biotechnology》1998,(1):629-639
The partitioning of xylanase produced byPenicillium janthinellum in aqueous two-phase systems (ATPS) using poly(ethylene glycol) (PEG) and phosphate (K2HPO4/KH2PO4) was studied employing a statistical experimental design. The aim was to identify the key factors governing xylanase partitioning.
The interactions of five factors (PEG concentration molecular weight, concentration of buffer K2HPO4/KH2PO4, pH, and NaCl concentration) and their main effects on the partition coefficient (K) were evaluated by means of a 25 full-factorial experimental design with four center points. The %PEG, %NaCl, and pH were the most important factors affecting
the response variable (K). Response surface methodology (RSM) was adopted and an empirical second-order polynomial model was
constructed on the basis of the results. The optimum partition conditions were pH 7.0, PEG = 8.83% and NaCl = 6.02%. Adequacy
of the model for predicting optimum response value was tested under these conditions. The experimental xylanase partition
coefficient (K) was 2.21, whereas its value predicted by the model was 2.33. These results indicate that the predicted model
was adequate for the process. PEG molecular weight and phosphate concentration did not affect the xylanase partition coefficient. 相似文献
104.
Saulute Budriene Natalija Gorochovceva Tatjana Romaskevic Lyubov V. Yugova Aldona Miezeliene Gervydas Dienys Asta Zubriene 《Central European Journal of Chemistry》2005,3(1):95-105
β-galactosidase from Penicillium canescens was immobilized on chitosan, sepharose-4B, foamable polyurethane and some other carriers. The highest yield of immobilization
(up to 98%) was obtained by using chitosan as a carrier. The optimum pH and temperature were not significantly altered by
immobilization. High stability of immobilized β-galactosidase during storage was demonstrated. Efficient lactose saccharification
(over 90%) in whey was achieved by using immobilized β-galactosidase. 相似文献
105.
Native fungal biomass of fungiAbsidia orchidis, Penicillium chrysogenum, Rhizopus arrhizus, Rhizopus nigricans, and modified spruce sawdust (Picea engelmanii) sequestered metals in the following decreasing preference pb>Cd>Ni. The highest metal uptake was qmax = 351 mg Pb/gA. orchidis biomass. P.chrysogenum biomass could accumulate cadmium best at 56 mg Cd/g. The sorption of nickel was the weakest always at < 5 mg Ni/g. The spruce
sawdust was modified by crosslinking, oxidation to acidic oxoforms, and by substitution. The highest metal uptake was observed
in phosphorylated sawdust reaching qmax = 224 mg Pb/g, 56 mg Cd/g, and 26 mg Ni/g. The latter value is comparable to the value of nickel sorption by wet commercial
resin Duolite GT-73. Some improvement in metal uptake was also observed after reinforcement of fungal biomass. 相似文献
106.
Two highly oxygenated polyketides, penilactones A and B (1 and 2), containing a new carbon skeleton formed from two 3,5-dimethyl-2,4-diol-acetophenone units and a γ-butyrolactone moiety, together with five known compounds (3-7) were isolated from an Antarctic deep-sea derived fungus Penicillium crustosum PRB-2. Penilactones A and B possess antipodal absolute stereochemistries. Their structures were elucidated by spectroscopic methods, and their absolute configurations were assigned by single-crystal X-ray diffraction and CD analyses. A plausible biogenetic pathway for 1-2 is proposed. 相似文献
107.
伍燕 《黔西南民族师范高等专科学校学报》2013,(4):122-124
从大自然中分离到的菌种因为生境不同,其生理特性等并不为人类生产所实用,所以要对其进行诱变、筛选以得到合适的工程菌种,该类微生物已在我们的生产、生活中占据了重要的地位。 相似文献
108.
Tao Liu Songya Zhang Zhanlin Li Yu Wang Zaixing Chen Jiao Bai 《Natural product research》2016,30(9):1025-1029
A new polyketide, penicillolide (1) was isolated from the fermentation broth of the marine-derived fungus Penicillium sacculum GT-308. Compound 1 is a polyketide with a unique carbon skeleton. The structure of this compound was established via extensive spectroscopic analyses including 1D-, 2D-NMR, and HRESI-MS. 相似文献
109.
播散性马尔尼菲青霉病嗜侵犯单核巨噬细胞系统,主要为骨髓、肝(枯否细胞)、脾、淋巴结和肺(尘细胞),引起一系列相应病变和症状:在骨髓最常引起巨噬细胞增生性炎,并吞噬大量病原体,但却无肿痛表现;但当引起化脓性溶骨性病变和波及关节引起关节炎时则出现该病唯一的自发性疼痛。本文报告6例并复习文献发现3例有骨及关节肿痛的病例。患者为中青年人,具有较强的炎症反应能力;同时都有骨外脓肿形成,好发生于扁骨和下肢关节;病灶都能培养出马尔尼菲青霉,但病变局部病原数量较少,组织中不易找见,必须用霉菌特殊染色,用免疫酶染色找抗原则更敏感;该病治疗不彻底易复发,需长期积极抗霉菌治疗。 相似文献
110.
研究了红树林植物尖瓣海莲叶内生真菌Penicillium sp.B21次级代谢产物。 用硅胶柱层析、制备薄层层析和重结晶等方法,从该菌发酵液的乙酸乙酯萃取相中首次分离获得5个单体化合物,运用现代波谱技术、单晶X射线衍射以及文献数据对照,鉴定其结构分别为8-羟基-6甲基-1-甲氧羰基酮(1)、大黄素(2)、ω-羟基大黄素(3)、(3R,4S)-6,8-二羟基-3,4,5-三甲基-3,4-二氢异香豆素(4)和3,6,8-三羟基-3,5,7-三甲基-3,4-二氢异香豆素(5)。 首次获得了sclerotinin B单晶结构。 相似文献