在农业土壤与有机残留物的放线菌的生态研究:II。放线菌菌株酶活性的评估
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土壤学1-1土壤在农林牧、人类及生态系统中有何意义?(1)土壤是农业最基本的生产资料。
土壤是地球的皮肤,在植物生长中起到营养库的作用、养分转化和循环作用、雨水涵养作用、生物的支撑作用以及稳定和缓冲环境变化的作用;(2)土壤是陆地生态系统的重要组成部分。
保持生物活性,多样性和生产性;对水体和溶质流动起调节作用;对有机、无机污染物具有过滤、缓冲、降解和解毒作用;具有贮存并循环生物圈及地表养分和其它元素的功能。
(3)土壤是最珍贵的自然资源。
土壤资源具有再生性,质量具有可变性,资源数量具有有限性;(4)土壤资源是可持续农业的基础。
可持续发展的条件之一就是资源破坏的零或负增长。
1-2什么是土壤、土壤圈?土壤有什么功能?何谓土壤肥力?土壤是在地球表面生物、气候、母质、地形、时间等因素综合作用下所形成能够生长植物的、处于永恒变化中的疏松矿物质与有机质的混合物。
1-3土壤与地球各圈层之间有何关系?2-1 常见的成土母质有那些?什么叫残积母质、洪积母质、冲积母质、风积母质?(1)残积母质:岩石风化后,基本上未经动力搬运而残留原地的风化物;(2)洪积母质:山洪搬运的碎屑物质在山前平原的沉积物。
(3)冲击母质:风化的碎屑物质,经河流常年性流水的侵蚀、搬运、沉积在河流两岸的沉积物。
沉积物具有成层性。
(4)风积母质:风积母质是风力搬运的堆积物,也是风蚀作用的产物,没有风蚀作用也就没有风积作用。
2-2岩石风化作用分那几个阶段?各阶段有何特点?(1)碎屑阶段:1) 岩石风化的最初阶段,以机械破碎为主的物理风化占优势,只有最易淋失的Cl、S发生移动;2) 风化壳中主要是粗大碎屑,产生碎屑风化壳,释放易溶于水的简单盐类,粘土矿物以水化度低的水云母为主;3)土壤类型为石质幼年土。
(2)钙沉积或饱和硅铝阶段:1) Cl、S已流失,Ca、Mg、K、Na等仍大部分保留,部分Ca游离出来,以CaCO3的形式,淀积在岩石碎屑孔隙中;2)产生碳酸盐风化壳,粘土矿物以蒙脱石最多,还含有水云母、绿泥石等;3)土壤类型为各类型钙积土。
土壤生物多样性评价与保护研究土壤生物多样性评价与保护研究一、引言土壤是地球生态系统中最重要和最丰富的生物栖息地之一,拥有丰富的生物多样性。
土壤生物多样性是指在特定土壤环境中存在的各种微生物、真菌、细菌、蚯蚓、线虫、昆虫等的种类和数量的多样性。
土壤生物多样性对实现农业可持续发展、维持生态系统功能以及保护全球生物多样性至关重要。
因此,评价和保护土壤生物多样性成为当今环境科学研究领域的一个重要课题。
二、土壤生物多样性评价方法评价土壤生物多样性的方法多种多样,常用的方法包括直接观察法、DNA技术法、生物标志物方法等。
直接观察法是通过野外调查和实验室观察来记录不同物种在土壤中的分布情况和数量。
DNA技术法利用特定的基因序列来鉴定和定量分析土壤中的微生物和其他生物种类,这种方法可以高效且准确地评价土壤生物多样性。
生物标志物方法则是通过研究特定生物类群及其数量来评价土壤的生物多样性情况。
三、土壤生物多样性保护策略保护土壤生物多样性需要综合多种策略,包括合理利用土地资源、保持土壤健康、减少污染物排放等。
首先,合理利用土地资源是保护土壤生物多样性的基础。
通过科学的耕作方式、合理的施肥措施,可以降低土壤质量退化的风险,保护土壤生物的多样性。
其次,保持土壤健康对于维护土壤生物多样性至关重要。
保持土壤的物理、化学和生物学性质平衡,增加土壤有机质含量,可以提供良好的生境条件,维持土壤生物多样性的稳定。
此外,减少污染物排放也是保护土壤生物多样性的一个重要方面。
土壤受到化学、生物和物理性污染的威胁,这些污染物会破坏土壤的生物多样性,因此减少污染物的排放是保护土壤生物多样性的一种有效途径。
四、国际土壤生物多样性保护研究进展目前,国际上已经开展了大量的土壤生物多样性保护研究。
这些研究主要包括土壤生物多样性的评价、影响土壤生物多样性的因素、土壤生物多样性对生态系统功能的影响等方面。
同时还关注土壤有机质的积累、土壤质量的改善等关键问题。
放线菌资源及其活性物质研究概述杨勇;李昆太【摘要】放线菌是一类(G+C)含量高的革兰氏阳性细菌,以丰富的次级代谢产物出名,在医药、农林业等方面具有重要利用价值.简要概述了放线菌的资源分布、分类方法及其代谢产物生物学功能,讨论了目前放线菌开发领域存在的问题及解决办法,以期为放线菌的开发应用研究提供参考.【期刊名称】《生物灾害科学》【年(卷),期】2019(042)001【总页数】8页(P7-14)【关键词】放线菌;次级代谢产物;资源分布;分类方法;生物学功能【作者】杨勇;李昆太【作者单位】江西农业大学生物科学与工程学院/江西省农业微生物资源开发与利用工程实验室,江西南昌 330045;江西农业大学生物科学与工程学院/江西省农业微生物资源开发与利用工程实验室,江西南昌 330045【正文语种】中文【中图分类】S476.1我国是一个人口资源众多的农业大国,农业发展具有十分重要的经济基础地位,关系着国计民生与社会稳定[1]。
然而,随着植物病害的频发,农作物生长受阻、产量和品质降低,再加上人口资源不断增加,可耕地面积急剧减少,导致全世界粮食的供给问题日益突出。
植物病害主要包括细菌、真菌和病毒性病害3种,其中真菌性病害占主导地位[2],是影响世界农作物产量的重要因素。
随着工业科学的进步,化学农药对农业生产带来巨大经济效益的同时,却也导致了诸多问题,如:环境污染、人类健康日益恶化、病虫耐药性增强和破坏生态平衡等。
这些危害的恶性循环,不仅增加了农业生产成本,破坏环境生态系统,还给病虫害防治带来了极大的困难。
微生物农药是指利用微生物及其代谢物和基因产物作为防治病虫草等有害生物、促进植物生长的生物制剂,利用其进行植物病害生防具有高效、无污染、无残留等优点,且不易产生抗性,是生物防治的重要手段[3]。
放线菌是一类(G+C)含量高的生防菌,广泛分布于自然界中,具有复杂的次级代谢系统,能产生诸多结构新颖、生物活性显著的代谢产物,是新医药和新农药研制的源头,在植物病害生防中具有重要意义。
有机氮分解菌的驯化筛选及其特性研究的开题报告一、研究背景氮素作为生命活动所必需的元素之一,在土壤生态系统中起着至关重要的作用。
有机氮分解是土壤中一个重要的氮素循环过程,其主要作用是将有机氮转化为无机氮并释放出来,以供植物吸收利用。
其中,有机氮分解菌是参与这一过程的重要微生物群体之一,在土壤环境中的生物转化过程中起到了至关重要的作用。
然而,有机氮分解菌的驯化筛选及其特性研究却是目前国内外研究的重要课题之一。
目前尚无较完整的有机氮分解菌驯化筛选体系,也没有对于有机氮分解菌的种类和特性进行深入的研究。
因此,本研究旨在为有机氮分解菌的驯化筛选及特性研究提供一定的理论与实践基础。
二、研究内容及方法1.研究内容本研究将着重从以下三个方面展开:(1)有机氮分解菌的筛选与驯化优化通过土壤样品的采集、处理和分离培养等方法,利用琼脂平板法、液体培养基发酵法等技术筛选出有机氮分解菌,并通过改变不同环境条件进行驯化与优化,如pH值、温度、碳源、氮源等。
(2)有机氮分解菌的种类鉴定与分类通过分子生物学技术,如16S rDNA序列测定等,鉴定已筛选出的有机氮分解菌的分类属及系统发育地位。
(3)有机氮分解菌的生理生化特性研究对已鉴定到的有机氮分解菌进行生理生化特性的研究,如生长速率、代谢途径、酶活性以及代谢产物等研究。
2.研究方法本研究采用如下方法:(1)土壤样品的采集、处理和分离培养;(2)琼脂平板法、液体培养基发酵法等技术进行有机氮分解菌的筛选与驯化优化;(3)16S rDNA序列测定等分子生物学技术对已筛选出的有机氮分解菌进行分类鉴定;(4)生理生化特性的研究,如生长速率、代谢途径、酶活性以及代谢产物等。
三、研究意义本研究的意义主要体现在以下几个方面:(1)对有机氮分解菌的种类及特性的研究可为土壤中氮素循环过程的进一步研究提供基础,有利于了解土壤的生物地球化学循环机制。
(2)有机氮分解菌的驯化及优化技术可为生产上有机废弃物的处理及再利用提供技术支撑,有利于环境保护与可持续发展。
1.农业废弃物指什么?如何分类?答:农业废弃物也称农业垃圾,按其成分,主要包括植物纤维性废弃物(农作物秸秆、谷壳、果壳及甘蔗渣等农产品加工废弃物)和畜禽粪便两大类,是农业生产和再生产链环中资源投入与产出在物质和能量上的差额,是资源利用过程中产生的物质能量流失份额。
一般意义上的农业废弃物,主要是指农业生产和农村居民生活中不可避免的一种非产品产出。
从资源经济学的角度上看,农业废弃物是某种物质和能量的载体,是一种特殊形态的农业资源。
农业废弃物按其来源不同可分为以下几种类型:(1) 第一性生产废弃物,主要是指农田和果园残留物,如作物秸秆、果树枝条、杂草、落叶、果实外壳等。
(2)第二性生产废弃物,主要是指畜禽粪便和栏圈垫物等。
(3)农副产品加工后的剩余物。
(4)农村居民生活废弃物,包括人粪尿及生活垃圾。
2.利用农村废弃物有什么意义?答:人类在开发利用自然资源进行社会化大生产的同时,必然产生许多废弃物。
农业生产中的废弃物种类繁多,数量巨大,但仅有很少部分农业废弃物被利用,农业资源被严重破坏和浪费。
此外,种植业和养殖业只注币粮、肉、蛋、奶等产品的利用,对大量的副产品弃之不顾。
这些废弃物既是宝贵资源,又是严重污染源,若不经妥善处理排入环境,将会严重污染环境。
如如果这一状况进一步恶化,必将会制约农业生产的发展。
另一方面,农村乡镇工业迅速发展对商品能源的需求也会日益增加。
因此,如何充分有效地利用农业废弃物,将其加工转化,制成再生能源及其系列产品,不仅对合理利用农业生产与生活资源,减少环境污染,改善农村生态环境具有十分重要的意义,而且在能源日益枯竭的情况下,农业固体废弃物作为一种能源,它的利用也将产生重大的影响。
农业固体废弃物的资源化利用正在进入科学化的新阶段,合理利用和推广这些技术,必将产生良好的经济效益、生态效益和社会效益。
3.植物纤维废弃物有什么特点?答:植物纤维性废弃物主要由植物细胞壁组成,它含有大量的粗纤维和无氮浸出物,也含有粗蛋白、粗脂肪、灰分和少量其他的成分。
新疆极端环境放线菌多相分类及抑菌活性物质研究新疆东部的吐鲁番盆地和南部的塔里木盆地由于长期干旱少雨,形成了戈壁、沙漠、盐湖等极端环境。
前期微生物多样性研究发现这些极端环境中分布着丰富而独特的放线菌。
本研究以分离自吐鲁番盆地和塔里木盆地极端环境中的放线菌为研究对象,对其中的放线菌新物种进行多相分类鉴定。
以对新疆棉花生产具有严重威胁的棉花黄萎病菌(大丽轮枝菌)为指示菌,筛选获得了高抑菌活性的放线菌。
对抑菌活性好的放线菌进行了代谢产物的分离鉴定和活性追踪,获得了高抑菌活性的单体化合物和新结构类型的化合物。
通过优化发酵工艺大幅提高了活性化合物的产量,并开展了活性化合物对大丽轮枝菌抑菌机理的初步研究。
具体研究结果包括:1.通过形态、系统发育、生理生化和化学分类特征的描述和比较,对3株分离自新疆极端环境中的放线菌进行了多相分类。
放线菌TRM 46004为假诺卡氏菌科的新物种,命名为吐鲁番长丝菌(Longimycelium tulufanense),并建立了长丝菌属;嗜盐放线菌TRM 46074为假诺卡氏菌科的新物种,命名为艾丁湖链多孢菌(Streptopolyspora aydingkolensis),与近源菌株一起建立了链多孢菌属;放线菌TRM 155-22为链霉菌属的新物种,命名为阿拉尔链霉菌(Streptomyces alarensis)。
2.以对新疆棉花生产具有严重威胁的棉花黄萎病菌(大丽轮枝菌)为指示菌,对分离自吐鲁番盆地和塔里木盆地的86株放线菌进行了抑菌活性筛选,获得了11株对大丽轮枝菌具有较强抑制活性的放线菌。
在抑菌活性指导下对链霉菌新物种TRM 155-22进行了代谢产物的分离和鉴定,获得了对大丽轮枝菌有强抑菌活性的蒽酮类化合物氧蒽酮霉素和2个新结构化合物。
经活性检测,氧蒽酮霉素还对尖孢镰刀菌、金黄色葡萄球菌、白色念珠菌等多种动、植物病原菌具有强抑制作用。
3.通过单因素实验、Plackett-Burman实验和响应面实验设计,对放线菌TRM155-22产氧蒽酮霉素的发酵工艺进行了优化。
Effects of subsoiling and the return of straw on soil bacterial diversity and community structure in anirrigated sierozem farmlandWEN Meijuan,YANG Sicun *,WANG Chengbao,HUO Lin(Institute of Soil Fertilizer and Water-saving Agriculture,Gansu Academy of Agriculture Sciences,Lanzhou 730070,China )Abstract :A field experiment was conducted to study the effect of 35cm subsoiling with the return of maize straw (STS ),35cm subsoiling (ST ),and conventional rotary tillage (RT )on the soil properties,soil bacterial diversity,and the community structure at a depth of 0–20cm on irrigated sierozem in the Gansu Yellow River irrigated area in 2015—2020.Results showed that,compared with RT and ST,STS could promote soil fertility,increase bacterial OTU numbers and the bacterial Alpha diversity.The distribution characteristics of the soil bacterialcommunities were significantly different.The soil pH,organic carbon (SOC ),water content (SWC ),cation exchange capacity (CEC ),total nitrogen (TN ),and alkali-hydrolyzable nitrogen (AHN )had significant or extremely significant correlations with bacterial α-diversity.Proteobacteria,Acidobacteria,Bacteroidetes,Actinobacteria and Chloroflexi were the dominant bacterial abundant in soil under different treatments at the phyla level,compared with ST and RT.STS could significantly increase the relative abundance of Proteobacteria and深松和秸秆还田对灌耕灰钙土土壤细菌多样性和群落结构的影响温美娟,杨思存*,王成宝,霍琳(甘肃省农业科学院土壤肥料与节水农业研究所,兰州730070)收稿日期:2022-04-18录用日期:2022-06-01作者简介:温美娟(1988—),女,甘肃天水人,助理研究员,主要从事土壤耕作与土壤环境的研究。
ORIGINAL PAPERStudies on the ecology of actinomycetes in an agricultural soil amended with organic residues:II.Assessment of enzymatic activities of Actinomycetales isolatesMokni-Tlili Sonia •Belguith Hafedh •Hassen Abdennaceur •Gargouri AliReceived:27February 2010/Accepted:10November 2010/Published online:17March 2011ÓSpringer Science+Business Media B.V.2011Abstract The main objective of this investigation was to study the enzymatic activities of Actinomycetales strains isolated from an agricultural soil amended with different amounts of municipal solid waste compost (MSWC)or farmyard manure (FM).For this purpose,the hydrolytic activities of carboxymethyl cellulase,xylanase,pectinase,amylase,chitinase and protease were tested for 75isolates of Sterptomyces ,Amycolatopsis and Nocardioides from dif-ferent sources (unamended soil,amended soil with FM or MSWC,FM and MSWC)at temperature ranging between 30and 50°C.It was shown that the highest rate of enzymes producer’s strains was registered at 30°C,and decreased gradually to annul at 50°C,with the exception of the MSWC strains origin.It was also shown that the percentage of strains producers of enzymes isolated from soil amended with MSWC appeared higher than the one registered for those isolated from control and amended with FM soils.Applica-tion of MSWC increases the number of enzymes producer-actinomycetes in the soil and then it improves its fertility.Keywords Actinomycetales ÁSoil amendment ÁMSW compost ÁFarmyard manure ÁHydrolytic activitiesIntroductionBecause are foremost producers of a large number of anti-biotics,enzymes and several other bioactive compounds,Actinomycetales ,Gram positive filamentous soil bacteria were commonly used in several industrial applications (Ben Ameur et al.2006;Goshev et al.2005;He et al.2010;Kumar and Kannabiran 2010;Qiu et al.2010).Streptomy-ces ,major members of the bacterial order Actinomycetales (see Part I of this paper)which play an important role in soil ecology (Xu et al.1996),are heterotrophic feeders.They utilize both simple and complex molecules as nutriment by the secretion of a hydrolytic enzymes variety.Among them,proteases (EC 3.4.21.19),a -amylases (EC 3.2.1.1),CMCase (EC 3.2.1.4),xylanases (EC 3.2.1.8),pectinases (EC 3.2.1.15)and chitinases (EC 3.2.1.14)have been widely studied over the past few years (Deng et al.2010;Feng et al.2010;Kolcuoglu et al.2010;Lee et al.2010;Li et al.2010;Poosarla et al.2010).These enzymes degrade plant polysaccharides such as cellulose,hemicellulose,starch,and animal com-pounds such as chitin.Enzymes with high thermal capacity were particularly attracted the attention of most researchers because of their considerable potential for numerous industrial applications.One extremely valuable advantage of conducting biotechno-logical processes at elevated temperatures is reducing the risk of contamination by common mesophiles.It can also increase the efficiency of the degradation process of substrate.Indeed,the substrates and products solubility increased and the med-ium viscosity decreased allowing an increase of the diffusion coefficients of substrates and therefore the reaction rate (Krahe et al.1996;Kumar and Swati 2001).For example,in the paper industry the wood used for the production of the pulp is treated at high temperature and basic pH,which implies that the enzymatic procedures require proteins exhibiting a highM.-T.Sonia (&)ÁH.AbdennaceurLaboratoire de Traitement et Recyclage des Eaux Use´es,Centre des Recherches et des Technologies des Eaux,Technopole de Borj Cedria,BP 273,8020Soliman,Tunisie e-mail:mt_sonia@yahoo.frB.Hafedh ÁG.AliLaboratoire de Ge´ne ´tique Mole ´culaire des Eucaryotes,Centre de Biotechnologie de Sfax,BP ‘‘K’’,3038Sfax,TunisiaWorld J Microbiol Biotechnol (2011)27:2251–2259DOI 10.1007/s11274-011-0688-4thermostability and activity in a broad pH range(Jacques et al. 2000).Treatment with xylanase at elevated temperatures disrupts the cell wall structure.This,as a result,facilitates lignin removal in the various stages of bleaching(Haki and Rakshit2003).Such enzymes are widely employed in food(Van der Maarel et al.2002),detergent(Abidi et al.2008),animal feed(Silva and Smithard2002),agriculture(Lorito et al. 1993),medicine(Emami and Diamandis2007),biotech-nology(Gupta et al.2002),textile(Milagres and Prade 1994),pulp and paper(Chen et al.1997)and waste man-agement(Aloise et al.1996)applications.Considering the importance of these enzymes and knowing that cellular components of thermophilic organ-isms(enzymes,proteins and nucleic acids)are also ther-mostable(Haki and Rakshit2003),there is ongoing interest in the isolation of new bacterial strains producing hydrolases suitable at high temperature for new industrial applications.In this study and at light of our previous work concerning the identification of the Actinomycetales dominant groups in soil(Part I of this paper),the present study aims atfirst to determine and to understand the effect of bacteria origin(soil, municipal solid waste compost(MSWC)or farmyard manure (FM))on their enzyme activities,and secondly to evaluate the capacity of Actinomycetales isolates to the decomposition of substrate that can be found in soil and organic amendments. This study was started by a screening of75Actinomycetale s isolates,originated of control or amended agricultural soil, producers of proteases,of amylases,of CMCase,of xylanases, of pectinase and of chitinases activities.Materials and methodsSoil and organic amendmentsThe soil samples were collected from an openfield in the experimental farm of the Agronomic National Institute of Tunis(see Fig.1—Part I of this paper).We recall here briefly that soil was treated with MSWC applied at40t ha-1(C40), 80t ha-1(C80)and120t ha-1(C120)and FM at40t ha-1 (F40)and120t ha-1(F120).Samples were collected from each plot,thoroughly and aseptically mixed to give homogenous samples,and stored directly at4°C prior to use.Isolation of actinomycetesA total of24soil,MSWC and FM samples were suspended in sterile water(10%)and agitated for30min at420rpm. The supernatant were serially diluted and plated on the glycerol–arginine–agar which contained(g l-1)glycerol—20,Arginine—2.5,NaCl—1,CaCO3—0.1,FeSO4Á7H2O—0.1,MgSO4Á7H2O—0.1,Agar—20.All colonies showing distinctive morphological characters were selected,purified and cryopreserved at-80°C in the appropriate liquid medium supplemented with20%of glycerol.The morphological characterization of isolates was investi-gated basing to Bergey’s ManualofDeterminativeBacteriology information(Lechevalier1989).The molecular characteriza-tion was done on the basis of PCR–RFLP-sequencing of16S rDNA gene methods(see part I of this paper).Revelation of hydrolytic enzymes on agar platesAmong281actinomycete strains isolated from agricultural soil,FM and MSWC,a collection of75strains were ran-domly isolated:15isolates from each treatment:soil T (untreated soil),soil C,soil F,MSWC and FM.Selected strains were spotted onto agar plates(20g l-1,pH7)con-taining:soluble starch(Sigma S2630),chitin(Fluka22719), xylan from oat spelts(Fluka95590),CMC(Sigma C4146) pectin(Sigma P9135)or gelatin(Sigma G9391)(all1%)and yeast extract(5g l-1).Enzymes activities were revealed, after5days of incubation,by the appearance of clear zones using iodine for amylase activity,Congo red for CMCase and xylanase activities and1%CTAB for pectinase activity. Chitinase and protease activities were revealed directly by the appearance of a clear zone by producer colonies.Different activities were tested at temperature ranging between30and50°C.Then,thermophilic Actinomycetales producers of enzymes were selected.Fermentation conditionsCultures which were able to produce clear zones for different enzymes in the agar plates at different temperature were sub-jected to submerged fermentation.Selected cells were culti-vated for9days(pH7,30°C)in250-ml Erlenmeyerflasks, maintained under agitation(150rpm),containing50ml of the growth medium composed of:carbon source(starch,chitin, xylan,gelatin,manure or compost),1%;K2HPO4,5g l-1; KH2PO4,1g l-1;(NH4)2SO4,1.4g l-1;Tween80,2ml; MnSO4ÁH2O,0.161g l-1;ZnSO4ÁH2O,0.21g l-1; CuSO4Á5H2O,0.051g l-1;CoSO4Á7H2O,5910-4g l-1 and FeSO4Á7H2O,0.051g l-1.The pH was adjusted to7 before autoclaving.After sterilization,the medium was completed by the addition of6ml of5%MgSO4Á7H2O and 10ml of3%CaCl2ÁH2O(Nisole et al.2006). Preparation of crude enzyme extracts and enzymatic assaysCulture media(1ml)were harvested every24h during 9days and centrifuged at7,000g for10min.Supernatants were than used as crude enzyme preparation.Amylase, chitinase and xylanase activities were determined using astandard assay at50°C for30min by measuring released reducing sugars from1%appropriate substrate(w/v)in 100mM phosphate buffer,pH7.The amount of released reducing sugars was determined by the dinitrosalicylic acid (DNS,Sigma D0550)method(Miller1959).D-Glucose, N-acetyl-D-glucosamine and xylose were used as standards. The absorbance at540nm(A540)was measured using a spectrophotometer(UV–VIS Dualbeam Model2700). One unit of enzyme activity was defined as the amount of enzyme that released1l mol of reducing sugars, expressed in glucose(for amylase),in N-acetyl-D-gluco-samine(for chitinase)and in xylose(for xylanase) equivalents per minute under the specified conditions. Protease assay with azocasein(Sigma A2765-56)hydro-lysis was performed according to the protocol described by Lee et al.(1995)with the modifications made by Abidi et al.(2007).The commercial azocasein(Sigma Chemical Co.,St.Louis,USA)was dissolved at5%(w/ v)solution in100mM phosphate buffer,pH7.Aliquots (150l l)of suitably diluted enzyme solution were added to50l l of5%(w/v)azocasein in reaction buffer (100mM phosphate,pH7)and the mixture was incu-bated at50°C for30min.The reaction was stopped by adding600l l of10%(w/v)trichloroacetic acid(TCA) and left for15min on ice,followed by centrifugation at 13,000rpm for5min to remove the precipitated protein. Supernatant(600l l)was neutralized by adding700l l of NaOH(1M)and the absorbance at440nm(A440)was measured.One unit of protease activity(UP)was defined as the amount of enzyme leading to an increase in absorbance(A440)of0.1per hour under the assay conditions.Results and discussionIsolation of actinomycetesIt was shown in the part I of this paper that the Actinomycetales isolates collection is composed by three families:Streptomycetaceae(72%),Pseudonocardiaceae (23%)and Nocardioidaceae(5%).A number of62 isolates from the above identified families and13 Actinomycetales isolates unidentified by sequencing method were selected to perform the enzymatic activi-ties tests(Table1).Some of these isolates,especially those belonging to Streptomycetaceae family were known by their important metabolic activities(Strepto-myces coelicolor,Streptomyces longisporoflavus)and can be involved in the degradation of several polymers present in the organic matter composition(antibiotic and enzymes;Bielen et al.2009;Usuki et al.2009).Revelation of hydrolytic enzymes on agar plates Enzymatic activity tests on agar plates were made for the 75selected strains.i.e.Fig.1showed the test result for some isolates originated from compost.A good zone of clearance,appeared within5days of incubation at pH7 and30°C,indicated that these strains can produce the following hydrolytic enzymes:CMCase,xylanase,amy-lase,pectinase,chitinase and protease.The ratio of the zone of CMC,starch,pectin and gelatin hydrolysis to the colonies diameter is high,indicating a good diffusibility of the enzymes.Figure2showed the enzyme-producers-strains rates versus the tested incubation temperatures(30,37,45and 50°C)for different strains origin(soil,MSWC or FM)and tested enzyme.It was clearly deduced that the enzymes production was strongly dependent on the work tempera-ture and on the isolates origin.Then,some either the tested enzyme:•The highest enzymes-producers-strains rate was recorded at30°C whatever the substrate and the origin of strains.It varied between20%,in the case of soil F-strains producer of pectinase(Fig.2d)and100%for the soil T and C-strains producer of CMCase(Fig.2a).For this same temperature of30°C,tested Strepromyces strains were rather producer of CMCase(strains rate[70%)and xylanase(strains rate[50%)than the other enzymes(strains rate\60%),except for those obtained from FM and MSWC.•A slight increase of temperature from30to37°C reduces the enzyme-producers-strains.As function of the origin,this decrease of the producer-strains ratio can be more or less important.Activities of FM-Strains were sharply decreased and almost totally inhibited whereas they were maintained(Fig.2a,b)or increased (Fig.2c–f)in the case of MSWC-isolates.For strains isolated from T,C and F soils,their activities were slightly decreased.•Beyond37°C,only some strains isolated from MSWC continued to produce enzymes.For45°C,the strain rate production decreased to reach nearly50%.This rate does not exceed15%for50°C.•The ratio of producer strains originated from amended soils(C and F)was more important than the one registered for soil T-strains.•Whatever the work temperature,the enzyme-producer-strains ratio is almost the highest for the one isolated from MSWC than those isolated from FM and soils T,C and M.The effect of temperature on reducing the strains pro-ducer enzymes number can be explained by the inhibitionof strains growth and/or activities(Fig.2).Indeed,the data illustrated in the9th edition of Bergey’s Manual(Cross 1989)showed that the majority of Actinomycetales are mesophilic.They grow for temperature ranging between25 and30°C.If temperature increases,only MSWC-strains maintain their activities(Fig.2).Indeed,the MSW composting process occurred in a temperature ranging from25to60°C. According to Albrecht(2007)the bacteria isolated from mature compost showed a large spectrum of growth and of activity in a wide range of pH and of temperature.Since,the actinomycetes appeared during the thermophilic phase as well as the cooling and maturation phase of composting process,these bacteria having a larger spectrum of tem-perature for the conversion of a wide range of natural substrates(cellulose,lignin)as compared to those from FM and soil(Chroni et al.2009;Huang et al.2010;Ryckeboer et al.2003;Tuomela2000).On the other hand,the effect of the isolate source on the enzymatic production can be attributed to its chemical composition.Since the studied amendments contained a high proportion of organic matter with respect to soilTable1Presentation of the species most related to tested isolates References of tested isolates Most related species Phylogenetic groupT1S.venezuelaeT2S.globisporus-subsp.globisporusT3,T4,T6,C5S.albidochromogenesT5S.flavofuscusT7Actinobacterium RG-51T8S.narbonensisT9,T14,T15,M14S.spiroverticillatusT10S.exfoliatesM1,M15,FM15S.claviferM2S.fradiaeM3S.sp.B267M4S.sp.Nm5M5,M11,FM8S.coelicolorM6S.sp.3004M7S.sp.AHW3M9S.sp.P3562M10,C2,C7S.spectabilis Streptomycetaceae C1,C4,C14,FM12,MSWC15S.longisporoflavusC3,FM2,FM3S.cavourensisC22S.sp.L42FM1,FM10,MSWC3S.collinusFM4S.sp.3004FM5,FM7S.californicusFM11,MSWC8,MSWC10S.sp.CHR28FM14,MSWC5,MSWC6,MSWC7,MSWC14S.sacchariMSWC1S.aureusMSWC2,MSWC4S.sp.A528MSWC9S.sp.AB654MSWC11S.griseoaurantiacusMSWC12S.azureusFM9Amycolatopsis sp.WX001Pseudonocardiaceae M8FM6FM13Nocardioides albus NocardioidaceaeT11,T12,T13,M12,M13,C6,C8,C9,C10,C11,C12,C13,MSWC13Unidentified(724g/kg in manure,404g/kg in compost and 17.5g/kg in soil;as reported by Ben Achiba et al.2009),it is likely that such medium more favored the development of strains able to produce enzymes serving to their mineralization.This fact can explain the highest registered ratios of FM and MSWC originated strains producer enzymes,especially for 30°C (Fig.2).At the same temperature,it appears that the proportion of enzyme-producers strains from MSWC is the higher compared to the one isolated from soil (Fig.2).This agree the results of Chroni et al.2009,Huang et al.2010and Tuomela et al.2000showing that Actinomycetales origi-nated from compost were considered among the bacteria responsible to the efficient degradation of cellulose and lignin.This was also observed for other bacteria originated from organic residues (Garcia-Gil et al.(2000);Madejon et al.(2003);Crecchio et al.(2004)and Benzarti et al.(2007)).In the case of CMCase and xylanase,the behavior of MSWC strains is due to the high content of cellulose,hemicellulose and lignin in the organic residues (Huang et al.2010;Kumar et al.2010;Paredes et al.2002).Indeed,the microbial metabolism must be adapted to the envi-ronmental conditions.In the same way,it was observed that the percentage of enzyme-producing strains originated from soil amended with MSWC is the higher compared to the one of theafedcb13245612345761765432654321 12345211a: MSWC7, 2a: MSWC2, 3a: MSWC1, 4a: MSWC4, 5a: MSWC10, 6a: MSWC81b: MSWC9, 2b: MSWC2, 3b: MSWC1, 4b: MSWC4, 5b: MSWC10, 6b:MSWC12, 7b: MSWC81c: MSWC9, 2c: MSWC2, 3c: MSWC1, 4c: MSWC4, 5c: MSWC10, 6c:MSWC12, 7c: MSWC81d: MSWC1, 2d: MSWC2, 3d: MSWC9, 4d: MSWC12, 5d: MSWC10, 6d: MSWC41e: MSWC9, 2e: MSWC2, 3e: MSWC1, 4e: MSWC4, 5e: MSWC101f: MSWC9, 2f: MSWC2Fig.1Enzymatic activities of some Streptomyces isolates shown on agar plates containing CMC,xylan,starch,pectin,chitin or gelatin (all 5g l -1):yeast extract (5g l -1)and agar (20g l -1);pH 7.0,T 30°C.CMCase (a ),xylanase (b ),amylase (c ),pectinase (d ),chitinase (e )and protease(f )MSWC:strains isolated from municipal solid waste compostother soils.Thisfinding was corroborated by several studies indicating that the enzyme activities were stimu-lated by the addition of organic amendments in soils (Crecchio et al.2004;Serra-Wittling et al.1996).More-over,Pascual et al.(1998)showed that the organic amendment sufficiently added to a semi-arid soil increased significantly the enzymatic activity for at least 360days.Therefore,the addition of mature compost to soil improves soil quality,promotes plant development and reduces the number of diseases caused by pathogens in soil(Cotxarrera et al.2002).For enzymatic production point of view,this compara-tive and qualitative investigation was often completed with a quantitative study by using broth culture(Ding et al. 2004;Techapun et al.2002;Yue et al.2008).Basing on the above presented results(Fig.2),the strain MSWC1originated from compost and affiliated to Streptomyces aureus with similarity about99%(see part I),was selected to determine its productive capacity of enzymes.Indeed, MSWC1present the ability to produce enzymes in all tested temperature on agar plates.Production of hydrolases in submerged culturesStreptomyces sp.MSWC1was cultivated on broth liquid medium under the above mentioned conditions and growth conditions yielding highest extracellular hydrolase activi-ties were optimized.It was shown(Mokni-Tlili et al.2010) that Streptomyces sp.MSWC1produced a large amount of extracellular enzymes in growth medium with suitable substrate and reached the maximum level after5days in the case of amylase activity(300IU ml-1)and3days for chitinase(110IU ml-1),xylanase(12,100IU ml-1)and protease(290IU ml-1)activities.The originality of these findings was that the production values for xylanase and chitinase activities were more important compared to those found in other studies using other Streptomyces strains (Ding et al.2004;Techapun et al.2002;Yue et al.2008). The substitution of the appropriate substrates with compost or manure decreases slightly the xylanase and chitinase and sharply the other enzymes production(Table2).This was attributed to the toxic effects exerted by the heavy metals, especially present in compost(Mokni-Tlili et al.2010). Despite this effect on enzyme production,the presence of these microorganism permit to valorize of biological wastes for the production of value-added products. ConclusionThis work investigated the assessment of enzymatic activities of Actinomycetales isolated from an agricultural soil amended with MSWC and FM and amendments.It was clearly shown that the enzymes production was strongly dependent on the incubation temperature and on the iso-lates origin.Then,some either the tested enzyme:•The highest enzymes-producers-strains rate was recorded at30°C whatever the substrate and the origin of strains.The increase of temperature decreases thepercentage of enzyme-producer-strains.For45°C,the active strains rate decreased to reach nearly50%.This rate does not exceed15%for50°C.•The ratio of producer strains originated from amended soils(C and F)was more important than the one registered for soil T.In addition,whatever the work temperature,the enzyme-producer-strains ratio is almost the highest for the one isolated from MSWC than those isolated from FM and soils T,C and M.Therefore,MSWC appeared clearly as a stimulator of enzymatic activities and a potential source of a thermotolerant enzyme-producing Streptomyces havinga wide industrial and biotechnological interest.On the other hand,it was shown that Streptomyces sp. MSWC1is able to produce hydrolases efficiently in the appropriate substrate,in manure and in compost.The high content of toxic heavy metals,especially in the compost, does not affect too much the hydrolase production by Streptomyces MSWC1strain,which is especially efficient in producing xylanase and chitinase activity.These hydrolytic activities produced by Streptomyces are impor-tant in the regulation of the ecosystem.In fact,they cata-lyze several essential reactions for the life processes of micro-organisms in soils.Therefore,they play a key role in the stabilization of soil structure,in the decomposition of organic wastes,organic matter formation and in nutrient cycling.Acknowledgments The present study is a part of the1999–2006 research program‘‘Municipal solid waste treatment and compost agricultural re-use’’which isfinancially by the Tunisian State Sec-retariat of Scientific Research and Technology.ReferencesAbidi F,Limam F,Marzouki MN(2007)Purification and character-ization of an alkaline protease Prot1from Botrytis cinerea.Assay as biodetergent catalyst.Appl Biochem Biotechnol141:361–376 Abidi F,Limam F,Marzouki MN(2008)Production of alkaline proteases by Botrytis cinerea using economic raw materials: assay as biodetergent.Process Biochem43:1202–1208 Albrecht R(2007)Co-Compostage de boues de station d’e´puration et de de´chets verts:Nouvelle me´thodologie du suivi des transfor-mations de la matie`re organique.The`se de Doctorat,Universite´Paul Cezanne AIX-Marseille III,p20Aloise PA,Lumme M,Aynes CA(1996)N-Acetyl-D-glucosamine production from chitin-waste using chitinases from Serratia marcescens.In:Muzzarelli RAA(ed)Chitin enzymology.Grottammare Edizioni,Ancona,Italy,pp581–594Ben Achiba W,Gabteni N,Lakhdar A,Du Laing G,Verloo M,Jedidi N,Gallali T(2009)Effects of5-year application of municipal solid waste compost on the distribution and mobility of heavy metals in a Tunisian calcareous soil.Agric Ecosyst Environ 130:156–163Ben Ameur Mehdi R,Sioud S,Fourati Ben Fguira L,Bejar S, Mellouli L(2006)Purification and structure determination ofTable2The maximum yield for tested enzymesMaximal enzymatic activity(IU/ml)Adequate substrat FM MSWCChitinase11010555 Prote´ase2904440 Amylase30012560 Xylanase12,10010,0009,400four bioactive molecules from a newly isolated Streptomyces sp.TN97strain.Process Biochem41:1506–1513Benzarti S,Hamdi H,Aoyama I,Jedidi N,Hassen A,Dahmane A (2007)Assessment of the effect of repetitive municipal solid waste compost application on soil using physico-chemical analyses,solid-phase bioassays and microbial activity charac-terisation.Jpn J Environ Toxicol10:19–30Bielen A,Cetkovic H,Long PF,Schwab H,Abramic M,Vujaklija D (2009)The SGNH-hydrolase of Streptomyces coelicolor has (aryl)esterase and a true lipase activity.Biochem91:390–400 Chen C,Adolphson R,Dean F,Eriksson K,Adamas M,Westpheling J(1997)Release of lignin from kraft pulp by a hyperthermo-philic xylanase from Thermotoga maritema.Enzyme Microb Tech20:39–45Chroni C,Kyriacou A,Georgaki I,Manios T,Kotsou M,Lasaridi K (2009)Microbial characterization during composting of bio-waste.Waste Manage29:1520–1525Cotxarrera L,Trillas-Gay MI,Steinberg C,Alabouvette C(2002)Use of sewage sludge compost and Trichoderma asperellum isolates to suppress Fusarium wilt of tomato.Soil Biol Biochem 34:467–476Crecchio C,Curci M,Pizzigallo MDR,Ricciuti P,Ruggiero P(2004) Effects of municipal solid waste compost amendments on soil enzyme activities and bacterial genetic diversity.Soil Biol Biochem36:1595–1605Cross T(1989)Growth and examination of actinomycetes-some guidelines.In:Williams ST,Sharpe ME,Holt JG(eds),Bergey’s Manual of Systematic Bacteriology,vol.4,Williams&Wilkins, Baltimore,pp2340–2343Deng A,Wu J,Zhang Y,Zhang G,Wen T(2010)Purification and characterization of a surfactant-stable high-alkaline protease from Bacillus sp.B001.Bioresour Technol101:7100–7106 Ding CH,Jiang ZQ,Li XT,Li LT,Kusakabe I(2004)High activity xylanase production by Streptomyces olivaceoviridis E-86.World J Microb Biot20:7–10Emami N,Diamandis EP(2007)New insights into the functional mechanisms and clinical applications of the kallikrein-related peptidase family.Mol Oncol1:269–287Feng B,Huang HZ,Zhou WB,Kang LP,Zou P,Liu YX,Yu HS,Han BQ,Li YY,Zhang LL,Zhang T,Ma BP(2010)Substrate specificity,purification and identification of a novel pectinase with the specificity of hydrolyzing the a-1,4-glycosyl residue in steroidal saponin.Process Biochem45:1383–1392Garcia-Gil JC,Plaza C,Soler-Rovira P,Polo A(2000)Long-term effects of municipal solid waste compost application on soil enzyme activities and microbial biomass.Soil Biol Biochem 32:1907–1913Goshev I,Gousterova A,Vasileva-Tonkova E,Nedkov P(2005) Characterization of the enzyme complexes produced by two newly isolated thermophylic actinomycete strains during growth on collagen-rich materials.Process Biochem40:1627–1631 Gupta R,Beg QK,Lorenz P(2002)Bacterial alkaline proteases: molecular approaches and industrial applications.Appl Micro-biol Biotechnol59:15–32Haki GD,Rakshit SK(2003)Developments in industrially important thermostable enzymes(rev).Bioresour Technol89:17–34He F,Yang Y,Yang G,Yu L(2010)Studies on antibacterial activity and antibacterial mechanism of a novel polysaccharide from Streptomyces virginia H03.Food Control21:1257–1262 Huang DL,Zeng GM,Feng CL,Hu S,Lai C,Zhao MH,Su FF,Tang L,Liu HL(2010)Changes of microbial population structure related to lignin degradation during lignocellulosic waste composting.Bioresour Technol101:4062–4067Jacques G,Frederic DL,Joste LB,Viviane B,Bart D,Fabrizio G, Benoit G,Jean-marie F(2000)An additional aromatic interac-tion improves the thermostability and thermophilicity of amesophilic family11xylanase:structural basis and molecular study.Protein Sci9:466–475Kolcuoglu Y,Colak A,Faiz O,Belduz AO(2010)Cloning, expression and characterization of highly thermo-and pH-stable maltogenic amylase from a thermophilic bacterium Geobacillus caldoxylosilyticus TK4.Process Biochem45:821–828Krahe M,Antranikian G,Markel H(1996)Fermentation of extrem-ophilic microorganisms.FEMS Microbiol18:271–285Kumar S,Kannabiran K(2010)Antifungal activity of Streptomyces VITSVK5spp.against drug resistant Aspergillus clinical isolates from pulmonary tuberculosis patients.J Med Mycol20:101–107 Kumar HD,Swati S(2001)Modern concepts of microbiology.Vikas Publishing House Pvt Ltd,New DelhiKumar M,Ou YL,Lin JG(2010)Co-composting of green waste and food waste at low C/N ratio.Waste Manage30:602–609 Lechevalier HA(1989)Nocardioform actinomycetes.In:Williams ST, Sharpe ME,Holt JG(eds),Bergey’s Manual of Systematic Bacteriology.vol.4,Williams&Wilkins,Baltimore,pp2348–2404 Lee CH,Kim HS,Kwon GS(1995)Purification and characterization of an alkaline protease produced by a Xanthomonas sp.YL-37.J Microbiol33:115–119Lee BH,Kim BK,Lee YJ,Chung CH,Lee JW(2010)Industrial scale of optimization for the production of carboxymethylcellulase from rice bran by a marine bacterium,Bacillus subtilis subsp.subtilis A-53.Enzyme Microbial Technol46:38–42Li AN,Yu K,Liu HQ,Zhang J,Li H,Li DC(2010)Two novel thermostable chitinase genes from thermophilic fungi:cloning, expression and characterization.Bioresour Technol101:5546–5551 Lorito M,diPietro A,Hayes CK,Woo SL,Harman GE(1993) Antifungal,synergistic interaction between chitinolytic enzymes from Trichoderma harzianum and Enterobacter cloacae.Phyto-pathol83:721–728Madejon E,Burgos P,Lopez R,Cabrera F(2003)Agricultural use of three organic residues:effect on orange production and on properties of a soil of the‘‘Comarca Costa de Huelva’’(SW spain).Nutr Cycle Agroecosyst65:281–288Milagres AMF,Prade RA(1994)Production of xylanases from Penicillium janthinellum and its use in the recovery of cellulosic textilefibers.Enzyme Microb Tech16:627–632Miller GL(1959)Use of dinitrosalicylic acid reagent for determina-tion of reducing sugars.Anal Chem31:426–428Mokni-Tlili S,Ben Abdelmalek I,Jedidi N,Belghith H,Gargouri A, Abdennaceur H,Marzouki MN(2010)Exploitation of biological wastes for the production of value-added hydrolases by Strep-tomyces sp.MSWC1isolated from municipal solid waste compost.Waste Manage Res28:828–837Nisole A,Lussier FX,Morley KL(2006)Extracellular production of Streptomyces lividans acetyl xylan esterase A in Escherichia coli for rapid detection of activity.Protein Expres Purif46:274–284 Paredes C,Bernal MP,Cegarra J,Roig A(2002)Bio-degradation of olive mill waste water sludge by its co-composting with agricultural wastes.Bioresour Technol85:1–8Pascual JA,Hernandez T,Garcia C,Ayuso M(1998)Enzymatic activities in an arid soil amended with urban organic wastes: laboratory experiment.Bioresour Technol64:131–138 Poosarla V,Giridhar T,Chandra S(2010)Production of novel halo-alkali-thermo-stable xylanase by a newly isolated moderately halophilic and alkali-tolerant Gracilibacillus sp.TSCPVG.Process Biochem45:1730–1737Qiu Z,Shi P,Luo H,Bai Y,Yuan T,Yang P,Liu S,Yao B(2010)A xylanase with broad pH and temperature adaptability from Streptomyces megasporus DSM41476,and its potential applica-tion in brewing industry.Enzyme Microbial Technol46:506–512 Ryckeboer J,Mergaert J,Coosemans J,Deprins K,Swings J(2003) Microbiological aspects of biowaste during composting in a monitored compost bin.J Appl Microbiol94:127–137。