光合细菌固定化技术及其应用研究进展

光合细菌是地球上出现最早,且自然界中普遍存在的一种具有原始光能合成体系的原核生物,是处于厌氧环境中可以进行不放氧光合作用的细菌总称。近年来,随着经济的发展与科技进步,光合细菌已被广泛应用到社会生产生活的各个领域。本文总结了光合细菌固定化技术使用的材料和方法,对光合细菌固定化技术在废水处理、生物制氢等方面的应用进行了深入探讨。     

光合细菌固定化及对养殖水净化的研究

采用海藻酸钠进行光合细菌固定化实验,比较了固定化菌和悬浮态菌的生长和生理特性,观察其在载体中的分布,并对其净化养殖水的能力进行初步研究。结果表明,固定化大大提高了光合细菌的生长速率;粒径为3.5mm,菌初始密度为0.12mg干菌泥/L为最佳固定化条件;在生长初期,菌在载体内的分布不均匀,后期趋于一致。在固定化菌净化养殖水的研究中发现,固定化光合细菌对养殖水的净化能力大大优于悬浮态菌。     

固定化光合细菌利用有机物产氢的研究

应用固定化细胞技术包埋荚膜红假单胞菌(Rhodopseudomonas capsulata)菌株386．研究在光照下利用有机物产氢的特性。实验观察到,光照培养120小时,悬浮培养物的产氢量为68．2ml·比产氢速率为104．1ml H2/g(生物量)·h;用琼脂包埋后．其产氢能力得到改善,产氢量和比产氢速率分别达到128．4ml和l 9s．8mlH2/g·h。该菌株除可利用苹果酸外,还可利用葡萄糖、乳酸、丙酸等基质高效地产氢。基质浓度只有控制在适当水平时,才具有较高的基质转化产氢效率。此外．菌体生物量、菌龄、培养液pH、光照强度、光照／黑暗时间比以及温度对产氢过程均有不同程度的影响。     

固定化技术在促进光合细菌产氢中的应用

氢气是一种新型的清洁高效能源,制氢技术的创新是目前研究的热点。将新型的技术及材料应用到生物制氢工艺中,从而促进生物制氢技术的产氢效率和工程应用是研究的重点之一。该文阐述了光合细菌在固定化生长条件下发酵产氢的最新研究进展,从固定化技术的原理、固定化方法的应用进展及影响因素几个方面进行了综述,详细阐述了包括包埋、悬浮载体附着生长及固定生物膜法等几种固定化方法对光发酵产氢的作用,介绍了国内外用于固定化的新型材料,并对今后的研究重点及方向进行了展望。     

光合细菌的分离、鉴定和固定化及其在净化鱼池水质中的应用研究

本文报告了光合细菌的分离、鉴定及固定在载体ＰＶＡ上,用于鲤鱼育苗池中净化水质的研究结果。并验分别用固定化光合细菌、游离光合细菌和对照三组,在三个鱼池中分别放养７００尾鱼苗,每５日测鱼池水中氨态氮一次,共测６次,其结果表明,应用固定化光合细菌的鱼池、氨的去除率高达９０％以上,有明显净化鱼池水质的作用,从而有利于鱼苗的生长。     

固定化光合细菌产氢过程的基质利用动力学

研究了固定化荚膜红假单胞菌386、红假单胞菌D两菌株产氢过程基质利用的动力学特性。基质利用与产氢过程以不同的速率进行．琼脂包埋固定化细胞的产氢能力高于海藻酸钙固定化细胞,但最大产氢活性的进程迟于后者。固定化D菌株利用葡萄糖的动力学遵循一级反应,其反应常数K值为1．2×10　2h-1。宏观动力学分析表明,利用基质的产氢过程属于反应控制,扩散传质过程不构成控速步骤。386和D两个菌株固定化细胞生物反应器连续产氢系统,在以乳酸作基质时．平均产氢量分别可达到0．659L／d和0．457L／d,容积(液相)产氢率接近1．OL／L·d。     

细菌的光合器与光合色素

大部分细菌无叶绿素,不能进行光合作用,但也有相当一部分细菌能够利用光作为能源、利用CO2作为碳源、以无机物作为供红体还原CO2合成生活所需的有机物质,这些细菌称之为光合细菌。光合细菌又根据它们在光合作用过程中的供氢体是无机物还是有机物而分为两类光合营养型。以无机物为供氢体的光合细菌称为光能自养型;以有机物为供氢体的光合细菌称为光合异养型。属于光能自养型的细菌例如绿硫细菌,其光合作用过程同高等绿色植物的光合作用过程相似,所不同的是高等绿色植物光合作用是以水作为CO。的还原剂,同时放出O。;而在绿硫细菌光…     

光合细菌的特性及其开发利用

人们通常将能进行光合作用的细菌统称为光合细菌。这是在水域中最复杂的菌群之一,也是地球上最早出现具有原始光能合成体系的原核生物、它们在自然界的分布十分广泛。无论是淡水、海水或是泥土中,甚至在水温很高含硫的温泉中都有它们的存在。早在19世纪人们即发现处于静水的池沼地带,此类细菌的大量繁殖时常能使水体变红,以后又注意到它们所处的生态环境与光和硫化氢的存在有直接关系,并发现它们的光合作用不同于一般藻类或高等植物,是具有不释放氧的特点。自30年代起,经范尼尔(Van Niel)的系统研究,才     

光合细菌及其应用现状

光合细菌以其独特的生理功能及其在环境和人类生活许多方面的广泛应用,受到了微生物、水产、环境等学科的重视,本文对光合细菌在水产养殖及有机废水处理等方面的应用现状进行了综述。     

光合细菌

光合细菌是地球上出现最早的具有原始光能合成体系的原核生物,是在厌氧条件下进行不放氧光合作用的细菌的总称,因具有细菌叶绿素和类胡萝卜素等光合色素,而呈现—定颜色。     

利用光合细菌进行微生物修复：一种降低辛硫磷在养殖水中积累的低成本方法

【背景】中国是农业生产大国,渔林农牧占比庞大。有机农药无论在畜牧业还是水产养殖业都有广泛的应用。有机磷农药(Organophosphorus Pesticide,OP)是应用最广泛的有机农药,具有低毒和不易残留的优点。OP在水体中大量积累可通过生物富集作用间接影响人体健康,由此产生的生殖毒性不容忽视。光合细菌作为环境友好型水体有益菌,部分菌种具有降解有机农药的功能。【目的】自上海海洋大学明湖中分离纯化得到一株光合细菌(编号SPZ)。探究其对辛硫磷的耐受程度及降解效果,为养殖水体中有机磷农药的生物降解提供目的菌株。【方法】利用16S rRNA基因序列分析方法对目标菌株进行种属鉴定;利用紫外分光光度法测定分离菌株SPZ和标准菌株ST在不同接种量下的OD660并测定实验周期内光合细菌在不同浓度辛硫磷中OD660的变化趋势,以示辛硫磷对光合细菌的毒性作用;利用高效液相色谱法(High Performance Liquid Chromatography,HPLC)测定菌株对水体辛硫磷的降解能力;通过HPLC测定加热致死菌与活菌对水体辛硫磷的降解能力,确定菌株对辛硫磷的降解方式。【结果】16S r...     

Reconsidering the use of photosynthetic bacteria for removal of sulfide from wastewater

The feasibility of using photosynthetic sulfide-oxidizing bacteria to remove sulfide from wastewater in circumstances where axenic cultures are unrealistic has been completely reconsidered on the basis of known ecophysiological data, and the principles of photobioreactor and chemical reactor engineering. This has given rise to the development of two similar treatment concepts relying on biofilms dominated by green sulfur bacteria (GSB) that develop on the exterior of transparent surfaces suspended in the wastewater. The GSB are sustained and selected for by radiant energy in the band 720-780 nm, supplied from within the transparent surface. A model of one of these concepts was constructed and with it the reactor concept was proven. The dependence of sulfide-removal rate on bulk sulfide concentration has been ascertained. The maximum net areal sulfide removal rate was 2.23 g m-(2) day-(1) at a bulk sulfide concentration of 16.5 mg L(-1) and an incident irradiance of 1.51 W m(-2). The system has a demonstrated capacity to mitigate surges in sulfide load, and appears to use much less radiant power than comparable systems. The efficacy with which this energy was used for sulfide removal was 1.47 g day(-1) W(-1). The biofilm was dominated by GSB, and evidence gathered indicated that other types of phototrophs were not present.     

一株紫色非硫光合细菌净化养殖水体初步研究

选取从杭州养鱼塘水样中分离得到的1株紫色非硫光合细菌菌株HZ-1,利用它的纯培养物处理养殖水体,测定COD去除率和亚硝态氮降解率。结果表明,菌株HZ-1可以有效地分解水体中的污染物,去除水体中的COD,对养鱼塘水去除率达到20.99%;对养虾池水去除率达到了36.09%;菌株HZ-1可以有效地降低水体的亚硝态氮,对养鱼塘水亚硝态氮的降解率为41.18%,具有较好净化效果。     

Copper-resistant bacteria from industrial effluents and their role in remediation of heavy metals in wastewater

Six copper-resistant bacterial strains were isolated from wastewater of tanneries of Kasur and Rohi Nala. Two strains tolerated copper at 380 mg/L, four up to 400 mg/L. Three strains were identified as members of the genusSalmonella; one strain was identified asStreptococcus pyrogenes, one asVagococcus fluvialis and the last was identified asEscherichia coli. The pH and temperature optimum for two of them were 7.0 and 30 °C, respectively; four strains had corresponding optima at 7.5 and 37 °C, respectively. All bacterial isola-tes showed resistance against Ag⁺ (280–350 mg/L), Co²⁺ (200–420), Cr^VI (280–400), Cd²⁺ (250–350), Hg²⁺ (110–200), Mn²⁺ (300–380), Pb²⁺ (300–400), Sn²⁺ (480–520) and Zn²⁺ (300–450). Largesized plasmids (>20 kb), were detected in all of the strains. After the isolates were cured of plasmids with ethidium bromide, the efficiency of curing was estimated in the range of 60–90%. Reference strain ofE. coli was transformed with the plasmids of the bacterial isolates which grew in Luria-Bertani medium containing 100 mg/L Cu²⁺. The capability to adsorb and afterwards accumulate Cu²⁺ inside their cells was assayed by atomic absorption spectrophotometer; all bacterial cells had the ability to adsorb 50–80 % of the Cu²⁺ and accumulate 30–45 % Cu²⁺ inside them after 1 d of incubation.     

Isolation,identification and growth conditions of photosynthetic bacteria found in seafood processing wastewater

Four photosynthetic bacteria, isolated from 14 samples taken from seafood processing plants, were identified as species of Rhodocyclus gelatinosus, belonging to the purple, non-sulphur bacteria of the family Rhodospirillaceae. Cultivation in synthetic medium under four different conditions indicated that all four strains gave maximum carotenoid and bacteriochlorophyll synthesis under anaerobic conditions in the light, with values of 11 to 12.6 and 102 to 108 mg/g dry cell wt, respectively. These values are 87% higher than the pigment content obtained from aerobic cultivation, although the cell biomass of all strains (1.7 to 2.3 g/l) was 22 to 38% higher under aerobic conditions. Protein content was always between 32 and 43%. The specific growth rates of all isolates in aerobic cultivation (0.04 to 0.06 h^-1) were twice those in anaerobic conditions in the light. No growth occurred in anaerobic conditions in the dark.     

Identification and cultivation of photosynthetic bacteria in wastewater from a concentrated latex processing factory

Ten strains of purple non-sulfur photosynthetic bacteria, isolated from wastewater produced by a concentrated latex processing factory, were cultivated in a wastewater medium without supplementation. After 40 h cultivation, one strain SS51, decreased the COD content of the wastewater by 34%. Optimal ratio of mixed-cultivation between SS51 and SY40 was 14:7 (ml/ml), and the COD content of the wastewater was decreased by 57%. Both strains were identified as Rubrivivax gelatinosus.     

Algal photosynthetic aeration increases the capacity of bacteria to degrade organics in wastewater

Wastewater treatment is an energy-intensive process and a net emitter of greenhouse gas emissions. A large fraction of these emissions is due to intensive aeration of aerobic bacteria to facilitate break-down of organic compounds. Algae can generate dissolved oxygen at levels in excess of saturation, and therefore hold the potential to partially displace or complement mechanical aeration in wastewater treatment processes. The objective of this study was to develop an internally consistent experimental and modeling approach to test the hypothesis that algal photosynthetic aeration can speed the removal of organic constituents by bacteria. This framework was developed using a simplified wastewater treatment process consisting of a model bacteria (Escherichia coli), a model algae (Auxenochlorella protothecoides), and a single carbon source that was consumable by bacteria only. This system was then tested both with and without the presence of algae. A MATLAB model that considered mass transfer and biological kinetics was used to estimate the production and consumption of O₂ and CO₂ by algae and bacteria. The results indicated that the presence of algae led to 18–66% faster removal of COD by bacteria, and that roughly one-third of biochemical oxygen demand was offset by algal photosynthetic aeration.     

光合细菌利用工业有机废水产生5-氨基乙酰丙酸

[目的]利用本实验室筛选的5-氨基乙酰丙酸(5-aminolevulinic acid,ALA)高产紫色非硫红假单胞菌株,以味精、柠檬酸、啤酒和豆制品生产废水作为底物,进行光合细菌利用废水产生ALA并去除化学需氧量(CODcr)的研究.[方法]光合细菌培养温度为30℃,光照强度为3000 Lux,进行乙酰丙酸、甘氨酸、琥珀酸的添加与否和废水灭菌与否的处理,用比色法测定菌液光密度,ALA检测采用Ehrlich'S试剂分光光度检测法.[结果]在不添加乙酰丙酸(levulinic acid,LA)、甘氨酸和琥珀酸的条件下,菌株99-28的菌体生长在72～96 h达到稳定期,ALA产量在96h最高,在4种废水中,味精废水的ALA产量最高,CODcr去除率也最高;添加LA、甘氨酸和琥珀酸显著提高ALA产量,但CODcr去除效果不好.废水不灭菌略微降低99-28菌株的生长和CODcr的去除能力,在添加LA、甘氨酸和琥珀酸的条件下的,ALA产量明显下降.ALA高产突变菌株L-1在有机废水中的生长状况、对有机废水的CODcr去除与菌株99-28表现一致,在不添加和添加LA、甘氨酸和琥珀酸的条件下,突变株L-1的ALA产量明显比菌株99-28高.[结论]本实验室筛选的紫色非硫红假单胞菌株能利用有机废水作为底物产生ALA并降解CODcr.     

Effects of dissolved oxygen on key enzyme activities during photosynthetic bacteria wastewater treatment

Photosynthetic bacteria (PSB) wastewater treatment is a novel method that can simultaneously achieve wastewater purification and recourse recovery. Oxygen conditions can significantly influence PSB metabolism and wastewater treatment; however, the roles of key enzymes in this process have been unclear. This study investigated the effects of different oxygen conditions on respiratory enzymes (hexokinase, HK; phosphofructokinase, PFK; and pyruvate kinase, PK) and the photosynthetic enzyme RuBisCO of PSB. The results showed that HK activity was almost the highest under anaerobic condition; PFK activity was the highest (311 nmol/min∙g) and PK the most quickly reached its peak under aerobic condition; and RuBisCO activity was the highest (107 nmol/min g) under anaerobic condition. The above results illustrated that HK might simultaneously regulate PSB growth and COD degradation, and its main role might be PSB growth regulation. PFK and PK might function in COD degradation while RuBisCO might function in PSB growth. Further, oxygen was beneficial for COD degradation and detrimental for PSB growth. This study provides a theoretical basis for the development of PSB wastewater treatment.     

Immobilization of lipase on chitin and its use in nonconventional biocatalysis

Chitin was functionalized with hexamethylenediamine followed by glutaraldehyde activation, and its capacity to bind Candida rugosa lipase was investigated. The loading of 250 units g(-1) support showed to be effective, resulting in a uniform enzyme fixation with high catalytic activity. Both free and immobilized lipases were characterized by determining the activity profile as a function of pH, temperature, and thermal stability. For the immobilized lipase, the influence of the reaction temperature and substrate polarity in nonconventional biocatalysis was also analyzed. Production of butyl esters was found to be dependent on the substrate partition coefficient, which accounts the greatest value for the system butanol and butyric acid. The highest enzyme activity was found for the system butanol and caprylic acid at a reaction temperature of 40 degrees C. Under such conditions, the operational stability tests indicated that a small enzyme deactivation occurs after 12 batches, revealing a biocatalyst half-life of 426.7 h.