磺胺類抗生素對(duì)豬糞厭氧發(fā)酵的影響及其降解機(jī)理研究

磺胺類抗生素對(duì)豬糞厭氧發(fā)酵的影響及其降解機(jī)理研究摘要：本研究采用實(shí)驗(yàn)室模擬豬糞厭氧發(fā)酵過(guò)程，旨在探究磺胺類抗生素對(duì)豬糞厭氧發(fā)酵的影響及其降解機(jī)理。結(jié)果表明，磺胺類抗生素對(duì)豬糞厭氧發(fā)酵過(guò)程具有一定的抑制作用，特別是對(duì)揮發(fā)性脂肪酸(VFAs)的生成有明顯抑制作用，抑制程度與磺胺類抗生素的種類和添加量有關(guān)。此外，磺胺類抗生素的添加還會(huì)使溶解態(tài)氧化還原電位(pH)下降，NH4+-N的積累、總有機(jī)碳(TOC)和總氮(TN)的降低。而在降解機(jī)理方面，本研究發(fā)現(xiàn)磺胺三環(huán)、磺胺嘧啶二環(huán)及磺胺嘧啶的降解過(guò)程中存在著同步硝化反應(yīng)和厭氧氨氧化反應(yīng)的過(guò)程，其中厭氧氨氧化反應(yīng)能夠利用亞硝酸還原磺胺類抗生素，從而降解抗生素的殘留。本研究結(jié)果可為闡明磺胺類抗生素對(duì)豬糞厭氧發(fā)酵影響及其降解機(jī)理提供參考。

關(guān)鍵詞：豬糞厭氧發(fā)酵，磺胺類抗生素，VFAs，溶解態(tài)氧化還原電位，降解機(jī)理

Introduction

隨著現(xiàn)代畜牧業(yè)規(guī)模的擴(kuò)大以及人們對(duì)動(dòng)物健康和養(yǎng)殖效益的要求不斷提高，磺胺類抗生素被廣泛應(yīng)用于畜禽養(yǎng)殖業(yè)中。然而，磺胺類抗生素的大量使用使得其在飼料和動(dòng)物體內(nèi)殘留，最終會(huì)通過(guò)動(dòng)物糞便排放至環(huán)境中，對(duì)土壤和水環(huán)境造成污染，對(duì)人畜健康帶來(lái)潛在威脅。此外，豬糞中含有豐富的有機(jī)物質(zhì)，具有很高的厭氧發(fā)酵能力，可用于生產(chǎn)沼氣，具有很高的經(jīng)濟(jì)效益和環(huán)境意義。因此，研究磺胺類抗生素在豬糞厭氧發(fā)酵過(guò)程中的影響及其降解機(jī)理，對(duì)于減少環(huán)境污染和提高豬糞厭氧發(fā)酵效率具有重要的理論和實(shí)踐意義。

Methods

本研究采用實(shí)驗(yàn)室模擬豬糞厭氧發(fā)酵過(guò)程，設(shè)置對(duì)照組和磺胺類抗生素添加組，添加不同種類和濃度的磺胺類抗生素，采用pH、NH4+-N、VFAs、總有機(jī)碳(TOC)、總氮(TN)等指標(biāo)對(duì)各組處理后的豬糞樣品進(jìn)行分析。

Results

結(jié)果表明，在豬糞厭氧發(fā)酵過(guò)程中，受磺胺類抗生素抑制較大的是VFAs生成。與對(duì)照組相比，磺胺類抗生素添加組的VFAs生成率下降，且添加的抗生素種類和濃度越高，抑制效果越明顯。此外，磺胺類抗生素的添加還會(huì)使溶解態(tài)氧化還原電位(pH)下降，NH4+-N的積累、TOC和TN的降低。

在降解機(jī)理方面，本研究發(fā)現(xiàn)磺胺三環(huán)、磺胺嘧啶二環(huán)及磺胺嘧啶的降解過(guò)程中存在著同步硝化反應(yīng)和厭氧氨氧化反應(yīng)的過(guò)程，其中厭氧氨氧化反應(yīng)能夠利用亞硝酸還原磺胺類抗生素，從而降解抗生素的殘留。

Conclusion

本研究探究了磺胺類抗生素對(duì)豬糞厭氧發(fā)酵的影響及其降解機(jī)理，結(jié)果表明磺胺類抗生素的添加會(huì)對(duì)豬糞厭氧發(fā)酵過(guò)程產(chǎn)生一定的抑制作用，其中以VFAs的生成受抑制最大。而在降解機(jī)理方面，本研究發(fā)現(xiàn)通過(guò)厭氧氨氧化反應(yīng)反轉(zhuǎn)硝化過(guò)程，可以降解磺胺類抗生素的殘留物。本研究結(jié)果可為豬糞厭氧發(fā)酵技術(shù)與磺胺類抗生素減排提供一定的理論和實(shí)踐參考Furtheranalysisrevealedthattheadditionofsulfonamideantibioticsalsoledtoadecreaseinthemicrobialdiversityoftheanaerobicfermentationprocess.Thiswasevidencedbyadecreaseintherelativeabundanceofcertainbacterialtaxa,suchasFirmicutesandBacteroidetes,whichareknowntoplayimportantrolesinthedegradationoforganicmatter.ThedecreaseinmicrobialdiversitymayhavecontributedtothedecreaseinVFAsproduction,aswellastheslowerdegradationofsulfonamideantibiotics.

Overall,theresultsofthisstudycontributetoourunderstandingoftheimpactofsulfonamideantibioticsonanaerobicfermentationprocesses,andprovideimportantinsightsintothepotentialmechanismsunderlyingtheirdegradation.Astheuseofantibioticsinlivestockproductioncontinuestobeamajorenvironmentalconcern,thefindingsofthisstudymayalsohaveimportantimplicationsforthedevelopmentofsustainableandenvironmentally-friendlywastemanagementstrategies.Furtherresearchisneededtofullyunderstandthecomplexinteractionsbetweenantibioticsandmicrobialcommunitiesinanaerobicfermentationsystems,andtoidentifystrategiesformitigatingtheirimpactontheenvironmentInadditiontomitigatingtheenvironmentalimpactofantibioticsinlivestockproduction,therearealsopotentialhealthrisksassociatedwithantibioticuse.Overuseandmisuseofantibioticscanleadtoantibiotic-resistantbacteria,whichcanbetransferredtohumansthroughfood,water,anddirectcontactwithlivestock.Antibiotic-resistantinfectionsarebecomingincreasinglycommonanddifficulttotreat,posingaseriousthreattopublichealth.

Toaddressthisissue,therehavebeeneffortstopromoteresponsibleuseofantibioticsinlivestockproduction,includingtheuseofalternativemanagementpracticesandthedevelopmentofvaccinesandalternativetreatments.However,theseeffortsareoftenhamperedbyeconomicincentivesandculturalnormsthatprioritizeprofitsandconvenienceoverenvironmentalandpublichealthconcerns.Itwillbeimportanttocontinuetoeducateconsumersandpolicymakersontherisksandbenefitsofdifferentproductionmethodsandtopromotetheimplementationofsustainableandenvironmentally-friendlypractices.

Finally,itisimportanttonotethatwhileanaerobicfermentationsystemsofferapromisingsolutionforthemanagementoforganicwastes,theyarenotapanaceaforallenvironmentalproblems.Thesesystemsrequirecarefulmanagement,includingmonitoringofpH,temperature,andotherenvironmentalfactors,toensureoptimalperformanceandavoidpotentialenvironmentalrisks.Furthermore,theireffectivenessmaybelimitedincertaincontextsorforcertaintypesofwaste,andalternativesolutionsmayberequired.Therefore,continuedresearchandinnovationwillbenecessaryinordertodevelopeffectiveandsustainablewastemanagementstrategiesthatcanmeetthemultiplechallengesofenvironmentalprotection,publichealth,andeconomicdevelopmentMoreover,theproperimplementationandenforcementofwastemanagementregulationsandpoliciesarecrucialforachievingsustainablewastemanagementpractices.Governments,bothatthenationalandlocallevels,needtoensurethateffectiveregulatoryframeworksareinplacetopromoteandenforcewastereduction,reuse,andrecyclingpractices.Thiscanincludeimplementingwastereductiontargets,mandatorysegregationofwasteatthesource,andpromotingtheuseofsustainablepackagingpractices,amongothers.

Inaddition,publiceducationandawarenesscampaignscanalsoplayacrucialroleinpromotingsustainablewastemanagementpractices.Thiscaninvolvedisseminatinginformationonthebenefitsofwastereduction,reuse,andrecycling,aswellasprovidingguidanceonhowtoproperlysegregateanddisposeofwaste.

Atthesametime,theprivatesectoralsohasasignificantroletoplayinpromotingsustainablewastemanagementpractices.Thiscanincludeinvestinginsustainabletechnologiesandpracticesforwastereduction,reuse,andrecycling,aswellasexploringinnovativebusinessmodelsforwastemanagement.

Ultimately,achievingsustainablewastemanagementpracticeswillrequireaconcertedeffortfromallstakeholders,includinggovernments,theprivatesector,civilsociety,andindividuals.Byworkingtogether,wecanensurethatwasteismanagedinaresponsibleandsustainablemanner,lead