Imwe yeinjini dzekusimudzira hupfumi muhafu yechipiri yezana ramakore rapfuura yaive mapurasitiki. Iwo akachipa, ari nyore kugadzira, anopokana, elastic uye, kana akasununguka, akajeka, asi ane b-side, sezvo asina biodegradable, sezvo pasina chipenyu chinokwanisa kudya pazviri.
Kugara kwenguva refu, pasina kupokana, rimwe rematambudziko makuru atinotarisana nawo, sezvo makore mashoma mazana mana nemakumi mashanu anofanirwa kupfuura kuti mapolymers atange hurongwa hwekuparara pamwero wemolecular.
Zvinofungidzirwa kuti anopfuura mamirioni mazana matatu ematani epurasitiki anogadzirwa pasi rose, ayo makumi mapfumbamwe muzana kubva mumafuta uye chikamu chidiki, chingangoita gumi neshanu muzana, chichadzoserwa uye kudzoserwa pasi rose.
Pachiyero ichocho chemuchadenga, avhareji yematani mamiriyoni masere anoguma ave kuyangarara gore negore mumakungwa edu, umo anonyura, anoungana mumatope kana kuti anoguma apinzwa mucheni yezvokudya zvevanhu.
Kufanotaura kwenguva pfupi hakukurudziri zvachose, mamwe manzwi ane mvumo anofungidzira kuti panosvika 2050 kugadzirwa kwemarara epurasitiki kuchasvika mabhiriyoni gumi nematatu ematani. Chimiro icho, pasina kupokana, chinotimanikidza kutora masimba uye nhanho dzekukurumidzira.
Tinotenda muna 2016 takaona kuvepo kwemubatsiri anogona uye, sezvakamboitika kakawanda munhoroondo yesainzi, serendipity yakaita basa rakakosha. Gore rino boka remasayendisiti echiJapan rakaongorora nzvimbo dzine utachiona pafekitari inogadzirwa patsva muguta reSakai, Japan. Munguva iyi takaongorora mabhakitiriya akatorwa kubva kune polyethylene terephthalate (PET) zvakasara mukuwedzera kune chikamu (ethylene glycol uye terephthalic acid).
Vashamiswa, vakaona kuti bhakitiriya, iro rainzi Ideonella sakaiensis, raigona kushandisa PET sechinhu chikuru che carbon source. Imwe nguva gare gare zvakagoneka kuratidza kuti hutachiona hune maviri akakosha majini anogona 'kudya' PET: PETase uye mono(2-hiroexieethyl) terephthalate hydrolase.
Mhinduro ine tariro
Kuwanikwa kweketani yemetabolism kwakaita kuti zvikwanise kutsanangura kuti sei Ideonella yakamisa pekugara muchirimwa chekudzokorodza, asi chasara kuti chiburitswe ndiyo yanga iri nzira yekuti bhakitiriya rive rakashanduka kuti rishandure purasitiki, iyo yaive patented mukati. Makumi gumi emakumi mana ezana ramakore rapfuura, munzvimbo yayo yechikafu.
Utachiona hunokwanisa kushandura PET kuita poly(3-hydroxybutyrate) - inozivikanwawo sePHB - inova mhando yepurasitiki inoodza. Chikumbiro chenyaya iyi ndechekuti PET inofungidzirwa kuti inoderedza pamwero we 0,13mg per square centimita pazuva, pakupisa kwe30ºC, chiyero chekubvisa chinova 'chinononoka zvakanyanya'.
Luck rakanyemwerera patiri zvakare muna 2018 apo vaongorori vepaPostmouth University (UK) vakagadzira netsaona enzyme inosimudzira hutachiona hwePETase.
Panguva ino, yakayedzwa kutora rimwe danho kuti iwedzere kubereka kwayo ne'kuisa' enzyme inoshanduka mubhakitiriya reextremophile, rinokwanisa kushingirira tembiricha iri pamusoro pe70ºC, chimiro icho PET inonyanya kuona. Uku 'kutamisa' kunogona kukurumidzira maitiro ekudzikisira kusvika pagumi%.
Zvese zvakawanikwa izvi zvinogona kutipa zororo uye kuvhura hwindo retariro, sezvo bhakitiriya 'inodya mapurasitiki' ingave chikamu chemhinduro kudambudziko rezvakatipoteredza rinokonzerwa nemapurasitiki.
Mr Jara
Pedro Gargantilla inyanzvi paEl Escorial Hospital (Madrid) uye munyori wemabhuku akati wandei anozivikanwa.
