M\u1ed9t \u0111\u0129a th\u1ee9c \u0103n \u0111\u1ec3 l\u00e2u th\u00ec s\u1ebd sinh ra m\u1ed9t s\u1ed1 sinh v\u1eadt nh\u1ecf b\u00e9. C\u00f3 khi ch\u00fang ta ch\u1ec9 bi\u1ebft th\u1ee9c \u0103n b\u1ecb bi\u1ebfn ch\u1ea5t nh\u01b0ng l\u1ea1i kh\u00f4ng th\u1ec3 nh\u00ecn th\u1ea5y nh\u1eefng sinh v\u1eadt nh\u1ecf b\u00e9 n\u00e0y. \u0110\u00f3 ch\u00ednh l\u00e0 b\u1edfi v\u00ec th\u1ecb l\u1ef1c c\u1ee7a ch\u00fang ta ch\u01b0a \u0111\u1ea1t \u0111\u1ebfn m\u1ee9c \u0111\u00f3. N\u1ebfu nh\u01b0 \u0111\u1eb7t th\u1ee9c \u0103n d\u01b0\u1edbi k\u00ednh hi\u1ec3n vi \u0111\u1ec3 ki\u1ec3m tra th\u00ec k\u1ebft qu\u1ea3 s\u1ebd khi\u1ebfn m\u1ecdi ng\u01b0\u1eddi ng\u1ea1c nhi\u00ean. Ho\u00e1 ra trong \u0111\u00f3 c\u00f3 h\u00e0ng ngh\u00ecn h\u00e0ng v\u1ea1n sinh v\u1eadt nh\u1ecf b\u00e9. Ch\u00fang ta g\u1ecdi nh\u1eefng sinh v\u1eadt nh\u1ecf b\u00e9 n\u00e0y l\u00e0 vi sinh v\u1eadt. V\u1eady th\u00ec vi sinh v\u1eadt trong th\u1ee9c \u0103n xu\u1ea5t hi\u1ec7n b\u1eb1ng c\u00e1ch n\u00e0o?<\/p>\n\n\n\n
Th\u1ef1c t\u1ebf \u0111\u1eb7t ra tr\u01b0\u1edbc m\u1eaft ch\u00fang ta l\u00e0, trong th\u1ee9c \u0103n v\u1ed1n kh\u00f4ng c\u00f3 vi sinh v\u1eadt, sau n\u00e0y ch\u00fang m\u1edbi sinh s\u00f4i ra. B\u1edfi v\u1eady, l\u00fac \u0111\u1ea7u m\u1ecdi ng\u01b0\u1eddi cho r\u1eb1ng vi sinh v\u1eadt l\u00e0 t\u1ef1 nhi\u00ean xu\u1ea5t hi\u1ec7n t\u1eeb trong th\u1ee9c \u0103n, h\u1ecdc thuy\u1ebft n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 thuy\u1ebft s\u1ea3n sinh t\u1ef1 nhi\u00ean c\u1ee7a vi sinh v\u1eadt.<\/p>\n\n\n\n
V\u00e0o th\u1ebf k\u1ec9 XVII, nh\u00e0 nghi\u00ean c\u1ee9u sinh v\u1eadt c\u1ee7a Italia ph\u1ee7 nh\u1eadn c\u00e1ch n\u00f3i n\u00e0y. \u00d4ng \u0111\u00e3 l\u00e0m m\u1ed9t cu\u1ed9c th\u1ef1c nghi\u1ec7m. Cu\u1ed9c th\u1ef1c nghi\u1ec7m nh\u01b0 sau: trong hai b\u00ecnh \u0111\u1ec1u \u0111\u1ec3 th\u1ecbt, m\u1ed9t b\u00ecnh m\u1edf n\u1eafp, c\u00f2n b\u00ecnh kia d\u00f9ng mi\u1ebfng v\u1ea3i m\u1ecfng b\u1ecbt k\u00edn. Sau m\u1ed9t th\u1eddi gian th\u00ec c\u00f3 ru\u1ed3i bay v\u00e0o trong b\u00ecnh m\u1edf n\u1eafp, ti\u1ebfp sau \u0111\u00f3 sinh ra d\u00f2i, c\u00f2n b\u00ecnh b\u1ecbt v\u1ea3i kia l\u1ea1i v\u1eabn kh\u00f4ng th\u1ea5y ru\u1ed3i v\u00e0 d\u00f2i. R\u00f5 r\u00e0ng th\u1ecbt thiu th\u1ed1i kh\u00f4ng th\u1ec3 xu\u1ea5t hi\u1ec7n ru\u1ed3i. Ru\u1ed3i ch\u1ec9 c\u00f3 th\u1ec3 l\u00e0 k\u1ebft qu\u1ea3 sinh s\u00f4i c\u1ee7a \u0111\u1eddi tr\u01b0\u1edbc. Cu\u1ed9c th\u1ef1c nghi\u1ec7m n\u00e0y c\u1ee7a Leidy \u0111\u00e3 ph\u1ee7 nh\u1eadn thuy\u1ebft s\u1ea3n sinh t\u1ef1 nhi\u00ean. Nh\u01b0ng nh\u1eefng ng\u01b0\u1eddi gi\u1eef \u00fd ki\u1ebfn ng\u01b0\u1ee3c l\u1ea1i th\u00ec cho r\u1eb1ng, ru\u1ed3i l\u00e0 lo\u00e0i \u0111\u1ed9ng v\u1eadt \u1edf b\u1eadc cao t\u01b0\u01a1ng \u0111\u1ed1i n\u00ean kh\u00f4ng th\u1ec3 t\u1ef1 nhi\u00ean ph\u00e1t sinh, nh\u01b0ng kh\u00f4ng c\u00f3 ngh\u0129a l\u00e0 vi sinh v\u1eadt c\u0169ng kh\u00f4ng th\u1ec3 t\u1ef1 nhi\u00ean ph\u00e1t sinh. T\u1ea1m th\u1eddi th\u00ec \u00fd ki\u1ebfn c\u1ee7a hai b\u00ean gi\u1eb1ng co v\u1eabn ch\u01b0a ng\u00e3 ng\u0169.<\/p>\n\n\n\n
\u00cdt l\u00e2u sau, khi b\u01b0\u1edbc v\u00e0o th\u1ebf k\u1ec9 XVIII. Cha c\u1ed1 c\u1ee7a \u0111\u1ea1o Thi\u00ean ch\u00faa \u0111\u1ed3ng th\u1eddi l\u00e0 nh\u00e0 nghi\u00ean c\u1ee9u sinh v\u1eadt c\u1ee7a Anh, John – Niderhan c\u0169ng \u0111\u00e3 l\u00e0m m\u1ed9t cu\u1ed9c th\u1ef1c nghi\u1ec7m \u0111\u1ec3 \u1ee7ng h\u1ed9 thuy\u1ebft s\u1ea3n sinh t\u1ef1 nhi\u00ean. \u00d4ng \u0111\u1ec3 n\u01b0\u1edbc th\u1ecbt c\u1eebu \u0111un n\u00f3ng tr\u00ean l\u1eeda 5 ph\u00fat, cho v\u00e0o trong b\u00ecnh v\u00e0 d\u00f9ng g\u1ed7 m\u1ec1m \u0111\u1eady k\u00edn. Theo l\u00ed thuy\u1ebft th\u00ec trong tr\u01b0\u1eddng h\u1ee3p n\u00e0y, vi sinh v\u1eadt v\u00e0 ru\u1ed3i trong kh\u00f4ng kh\u00ed kh\u00f4ng c\u00f3 c\u00e1ch n\u00e0o chui v\u00e0o trong b\u00ecnh \u0111\u01b0\u1ee3c, c\u0169ng kh\u00f4ng th\u1ec3 c\u00f3 vi sinh v\u1eadt n\u00e0o sinh s\u00f4i \u0111\u01b0\u1ee3c. Nh\u01b0ng sau v\u00e0i ng\u00e0y, k\u1ebft qu\u1ea3 ki\u1ec3m tra l\u1ea1i ho\u00e0n to\u00e0n tr\u00e1i ng\u01b0\u1ee3c l\u1ea1i: trong n\u01b0\u1edbc th\u1ecbt c\u1eebu c\u00f3 r\u1ea5t nhi\u1ec1u vi sinh v\u1eadt \u0111ang ho\u1ea1t \u0111\u1ed9ng. V\u1eady l\u00e0 thuy\u1ebft ph\u00e1t sinh t\u1ef1 nhi\u00ean \u0111\u00e3 t\u00ecm ra \u0111\u01b0\u1ee3c nh\u1eefng ch\u1ee9ng c\u1ee9 m\u1edbi.<\/p>\n\n\n\n
Ch\u00ednh v\u00e0o th\u1eddi \u0111i\u1ec3m n\u00e0y, \u1edf Italia \u0111\u00e3 xu\u1ea5t hi\u1ec7n m\u1ed9t nh\u00e0 khoa h\u1ecdc t\u00ean l\u00e0 Lazzaro Spallanzani. Spallanzani cho r\u1eb1ng, khuy\u1ebft \u0111i\u1ec3m c\u1ee7a Niderhan c\u00f3 th\u1ec3 xu\u1ea5t hi\u1ec7n \u1edf kh\u00e2u \u0111un n\u00f3ng trong 5 ph\u00fat n\u00e0y, n\u1ebfu nh\u01b0 5 ph\u00fat kh\u00f4ng \u0111\u1ee7 \u0111\u1ec3 gi\u1ebft ch\u1ebft t\u1ea5t c\u1ea3 c\u00e1c vi sinh v\u1eadt \u1edf trong b\u00ecnh, v\u1eady th\u00ec k\u1ebft qu\u1ea3 n\u00e0y l\u00e0 b\u00ecnh th\u01b0\u1eddng. B\u1edfi v\u1eady, \u00f4ng Spallanzani \u0111\u00e3 ph\u1ecfng theo ph\u01b0\u01a1ng ph\u00e1p c\u1ee7a Niderhan \u0111\u1ec3 l\u00e0m m\u1ed9t cu\u1ed9c th\u1ef1c nghi\u1ec7m, \u00f4ng \u0111\u1ed5 n\u01b0\u1edbc th\u1ecbt c\u1eebu v\u00e0o trong m\u1ea5y b\u00ecnh, sau khi \u0111un n\u00f3ng b\u1ecbt k\u00edn mi\u1ec7ng b\u00ecnh, trong \u0111\u00f3 m\u1ed9t b\u00ecnh \u0111un n\u00f3ng 5 ph\u00fat, c\u00e1c b\u00ecnh c\u00f2n l\u1ea1i \u0111un n\u00f3ng 1 gi\u1edd.<\/p>\n\n\n\n
V\u00e0i ng\u00e0y sau, Spallanzani \u0111\u00e3 ki\u1ec3m tra, nh\u1eadn th\u1ea5y trong b\u00ecnh \u0111\u1ef1ng n\u01b0\u1edbc th\u1ecbt c\u1eebu \u0111un n\u00f3ng 5 ph\u00fat th\u00ec c\u00f3 \u0111\u1ea7y vi sinh v\u1eadt, c\u00f2n trong b\u00ecnh \u0111\u1ef1ng th\u1ecbt c\u1eebu \u0111un n\u00f3ng 1 gi\u1edd th\u00ec kh\u00f4ng c\u00f3 s\u1ef1 t\u1ed3n t\u1ea1i c\u1ee7a b\u1ea5t k\u00ec vi sinh v\u1eadt n\u00e0o. S\u1ef1 vi\u1ec7c \u0111\u1ebfn \u0111\u00e2y \u0111\u00e3 \u0111\u01b0\u1ee3c ch\u1ee9ng minh r\u1ea5t r\u00f5 r\u00e0ng r\u1ed3i, nh\u01b0ng Niderhan \u0111\u00e3 ph\u1ea3n k\u00edch l\u1ea1i: “\u0110un n\u00f3ng 1 gi\u1edd kh\u00f3 m\u00e0 l\u00e0m cho vi sinh v\u1eadt sinh s\u00f4i t\u1ef1 nhi\u00ean s\u1ee3 m\u00e0 ch\u1ebft h\u1ebft s\u1ea1ch \u0111\u01b0\u1ee3c, h\u01a1n n\u1eefa, Spallanzani d\u00f9ng ph\u01b0\u01a1ng ph\u00e1p khi \u0111un n\u00f3ng b\u1ecbt k\u00edn b\u00ecnh, e r\u1eb1ng \u0111\u00e3 \u0111\u1ea9y h\u1ebft kh\u00f4ng kh\u00ed trong b\u00ecnh ra ngo\u00e0i, trong tr\u1ea1ng th\u00e1i ch\u00e2n kh\u00f4ng th\u00ec vi sinh v\u1eadt t\u1ed3n t\u1ea1i l\u00e0m sao \u0111\u01b0\u1ee3c\u201d?<\/p>\n\n\n\n
Hi\u1ec3n nhi\u00ean l\u00e0 Niderhan \u0111\u00e3 \u0111u\u1ed1i l\u00ed, do vi sinh v\u1eadt \u0111\u00e3 c\u00f3 th\u1ec3 ph\u00e1t sinh t\u1ef1 nhi\u00ean th\u00ec s\u1ebd kh\u00f4ng c\u1ea7n t\u1edbi \u0111i\u1ec1u ki\u1ec7n n\u01b0\u1edbc \u0111\u00e3 \u0111un n\u00f3ng bao l\u00e2u, v\u1ea5n \u0111\u1ec1 ch\u1ec9 l\u00e0 trong tr\u1ea1ng th\u00e1i ch\u00e2n kh\u00f4ng th\u00ec k\u1ebft qu\u1ea3 th\u1ef1c nghi\u1ec7m li\u1ec7u \u0111em l\u1ea1i c\u00f9ng m\u1ed9t k\u1ebft qu\u1ea3 kh\u00f4ng. Trong tr\u01b0\u1eddng h\u1ee3p n\u00e0y, Spallanzani khi ti\u1ebfn h\u00e0nh cu\u1ed9c th\u1ef1c nghi\u1ec7m ti\u1ebfp theo, \u0111\u1eb7c bi\u1ec7t ch\u00fa \u00fd khi b\u1ecbt k\u00edn b\u00ecnh tr\u00e1nh \u0111\u1ec3 kh\u00f4ng kh\u00ed l\u1ecdt ra ngo\u00e0i, k\u1ebft qu\u1ea3 ch\u1ee9ng minh l\u00e0 ho\u00e0n to\u00e0n gi\u1ed1ng nhau, nh\u01b0 v\u1eady, cu\u1ed1i c\u00f9ng Niderhan \u0111\u00e3 kh\u00f4ng th\u1ec3 n\u00f3i v\u00e0o \u0111\u00e2u \u0111\u01b0\u1ee3c n\u1eefa.<\/p>\n\n\n\n