Izimila Umthombo Owusizo Wemithi

Izazi zilinganisela ukuthi ingxenye yesine yayo yonke imithi yesilungu abantu abathembele kuyo yaqala—yonke noma ngokwengxenye—ingamakhemikhali atholakala ezimileni. Izishisekeli zemithi engamakhambi ehlukahlukene zivame ukuliveza leli phuzu.

Ucwaningo oluningi olwenziwa ezimileni ezisetshenziselwa ukwelapha luqondiswe ekutholeni izakhi ezelaphayo kuzo. Isibonelo esivelele salokhu yi-aspirin, etholakala kuyi-salicin, ikhemikhali etholakala emagxolweni omnyezane omhlophe.

Lapho leso sakhi eselaphayo sesitholakele esimileni, singasetshenziswa ngezilinganiso ezanele futhi ezinembe kakhudlwana. Enye incwadi ithi: “Uma ufuna amagxolo omnyezane anele ukuze uthole izinzuzo ezinikezwa yi-aspirin noma ufuna i-foxglove eyanele ukuze uthole amandla asindisa ukuphila anikezwa yi-digitalis ekuyo ungakwenza kalula kakhulu ngokusebenzisa iphilisi kunokudla leso simila ngokwaso.”

Ngakolunye uhlangothi, ukuthola leso sakhi eselaphayo bese kukhishwa sona sodwa esimileni esisetshenziselwa ukwelapha kungaba nemiphumela engemihle. Ngokwesibonelo, kungase kusho ukulahlekelwa yizo zonke ezinye izinzuzo zokunonophalisa umzimba nezokwelapha ezitholakala kwezinye izakhi ezikulesi simila. Ngaphezu kwalokho, ezinye zezilokazane ezidala izifo ziyamelana nemithi ezibulalayo.

I-quinine (isithako somuthi kamalaleveva) etholakala emagxolweni omjele, iyisibonelo semiphumela engemihle yokukhipha isakhi esisodwa eselaphayo esimileni esisetshenziselwa ukwelapha. Yize i-quinine ibulala iningi lezilokazane ezidala umalaleveva, lezo engazibulali zanda kakhulu lapho kufa ezinye. Enye incwadi iyachaza: “Lokho kumelana nemithi sekuyinkinga enkulu kwezokwelapha.”

[Izithombe ekhasini 31]

I-“aspirin” itholakala kulo mnyezane omhlophe

[Umthombo]

USDA-NRCS PLANTS Database/Herman, D.E. et al. 1996. North Dakota tree handbook

[Isithombe ekhasini 31]

Uhlobo lomuthi womjele okutholakala kuwo i-“quinine”

[Imithombo ekhasini 31]

Courtesy of Satoru Yoshimoto