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PENETAPAN KADAR MINERAL KALSIUM, KALIUM, MAGNESIUM, DAN NATRIUM PADA SELADA ROMAINE (Lactuca sativa var.
longifolia Lam.) ORGANIK DAN NON-ORGANIK SECARA SPEKTROFOTOMETRI SERAPAN ATOM
ABSTRAK
Selada romaine merupakan salah satu varietas dari selada yang merupakan tumbuhan yang berasal dari suku compositae. Tanaman ini banyak dikenal masyarakat sebagai lalapan. Kandungan gizi dari selada ini antara lain sebagai sumber mineral, pro-vitamin A, vitamin C, dan serat. Selain ditanam secara non-organik tanaman ini juga dapat ditanam secara non-organik. Banyak keuntungan yang dapat diperoleh dengan mengonsumsi sayuran organik dibanding sayuran non-organik. Di antaranya rasa lebih manis, tekstur lebih renyah, segar lebih lama, dan paling penting bebas dari residu bahan kimia yang membahayakan kesehatan. Tujuan dari penelitian ini adalah untuk mengetahui kadar mineral kalsium, kalium, magnesium, dan natrium pada selada romaine organik dan non-organik serta mengetahui perbedaan kadar mineral antara selada romaine organik dan non-organik.
Untuk mengetahui kadar mineral kalsium, kalium, magnesium, dan natrium pada selada romaine yang diteliti dilakukan penetapan kadar menggunakan spektrofotometer serapan atom nyala udara-asetilen. Analisis kuantitatif kalsium, kalium, magnesium, dan natrium dilakukan pada panjang gelombang berturut-turut 422,7 nm, 766,5 nm, 285,2 nm, dan 589,0 nm.
Hasil penelitian menunjukkan bahwa kadar mineral kalsium, kalium, magnesium, dan natrium dalam selada romaine organik adalah (109,2111 ± 0,2454) mg/100g; (575,8676 ± 0,8555) mg/100g; (151,8046 ± 0,1241) mg/100g; (10,9818 ± 0,2097) mg/100g. Serta kadar mineral kalsium, kalium, magnesium, dan natrium dalam selada romaine non-organik adalah (66,3873 ± 0,4059) mg/100g; (366,3379 ± 1,0117) mg/100g; (97,2027 ± 0,1702) mg/100g; (5,2111 ± 0,2533) mg/100g. Hasil uji statistik yaitu uji beda rata-rata kadar mineral antara selada romaine organik dan non-organik menunjukkan bahwa terdapat perbedaan yang signifikan kadar masing-masing mineral kalsium, kalium, magnesium, dan natrium antara selada romaine organik dan non-organik dengan tingkat kepercayaan 99%.
Kata kunci : selada romaine (Lactuca sativa var. longifolia Lam.), organik, non-organik, kalsium, kalium, magnesium, natrium, spektrofotometer serapan atom
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DETERMINATION OF CALCIUM, POTASSIUM, MAGNESIUM AND SODIUM LEVEL IN ORGANIC AND INORGANIC ROMAINE LETTUCE (Lactuca sativa var. longifolia Lam.) BY
ATOMIC ABSORPTION SPECTROPHOTOMETRY
ABSTRACT
Romaine lettuce is one of varieties of lettuce which is a local plant of the compositae. This plant is well known as vegetables are eaten raw. Nutrients content of this lettuce are as minerals resources, pro-vitamin A, vitamin C, and fiber. Aside from inorganically grown, these plants can also be grown organically. Many benefits can be obtained by eating organic vegetables than inorganic vegetables. It included sweeter taste, crisper texture, fresh for longer, and most importantly free from chemical residues that harms health. The purpose of this study are to determine mineral content of calcium, potassium, magnesium, and sodium in the organic and inorganic romaine lettuce and also knowing the difference between mineral content of the organic romaine lettuce and the inorganic romaine lettuce.
To determine the mineral content of calcium, potassium, magnesium, and sodium in romaine lettuce under study were conducted by using atomic absorption spectrophotometer with air-acetylene flame. Quantitative analysis of calcium, potassium, magnesium, and sodium were perfomed at 422.7 nm, 766.5 nm, 285.2 nm, and 589.0 nm wave length.
The results showed that the levels of the minerals calcium, potassium, magnesium, and sodium in the organic romaine lettuce were (109.2111 ± 0.2454) mg/100g; (575.8676 ± 0.8555) mg/100g; (151.8046 ± 0.1241) mg/100g; and (10.9818 ± 0.2097) mg/100g. As well as the levels of the minerals calcium, potassium, magnesium, and sodium in the inorganic romaine lettuce were (66.3873 ± 0.4059) mg/100g; (366.3379 ± 1.0117) mg/100g; (97.2027 ± 0.1702) mg/100g; and (5.2111 ± 0.2533) mg/100g. The results of statistical tests that test the average difference between the mineral content of the organic romaine lettuce and the inorganic romaine lettuce showed that there were significant difference of each mineral contents of calcium, potassium, magnesium, and sodium between the organic romaine lettuce and inorganic romaine lettuce with a level of confidence 99%.
Keywords : romaine letuce (Lactuca sativa var. longifolia Lam.), organic, inorganic, calcium, potassium, magnesium, sodium, atomic absorption spectrophotometer
