Jurnal+uji+molisch+karbohidrat+patched

Introduction to the Molisch Test

The Molisch test, named after the Austrian chemist Hans Molisch, is a sensitive chemical test used for detecting the presence of carbohydrates (sugars). It is a general test that can be applied to any type of carbohydrate, including monosaccharides, disaccharides, and polysaccharides, though it is more commonly used to detect the presence of carbohydrates in a solution rather than to quantify them.

LAPORAN PRAKTIKUM KIMIA ORGANIK

Abstrak

Uji Molisch adalah reaksi kimia sensitif untuk mendeteksi kehadiran karbohidrat berdasarkan pembentukan warna ungu ketika gula terdehidrasi menjadi furfural atau hidroksimetilfurfural yang bereaksi dengan reagen α-naftol. Artikel ini menjelaskan prosedur eksperimen yang dimodifikasi (patched) untuk meningkatkan reproducibility dan keselamatan, menyajikan data kuantitatif dari sampel makanan dan polisakarida murni, serta membahas batas deteksi, interferensi, dan aplikasi analitik dalam kontrol mutu pangan. jurnal+uji+molisch+karbohidrat+patched

5. Results (Example Table)

| Sample | Patch Test Result | Conventional Molisch | |--------------|------------------|----------------------| | Glucose | Purple ring | Purple ring | | Starch | Purple ring | Purple ring | | Sucrose | Purple ring | Purple ring | | Glycine | No color | No color | | Water | No color | No color | Introduction to the Molisch Test The Molisch test,

• Include photographs of patches before/after acid addition.

4.2 Reagents

• Molisch reagent (5% α-naphthol in ethanol).
• Concentrated H₂SO₄ (caution: corrosive).

2. Abstract (150–250 words)

• Background: Molisch test is a general test for carbohydrates using α-naphthol and concentrated H₂SO₄.
• Objective: To adapt the Molisch test for patched samples (e.g., food spots, dried extracts, or surface swabs on filter paper).
• Methods: Samples were applied as a small patch on filter paper, followed by α-naphthol reagent and acid. Color development was observed.
• Results: Positive results (purple ring) were obtained with all tested carbohydrates (glucose, sucrose, starch) but not with non-carbohydrates.
• Conclusion: The patched method is simple, sample-saving, and suitable for field or preliminary testing.

V. HASIL PENGAMATAN

| No. | Tabung | Isi Sampel | Hasil Pengamatan | Kesimpulan | |:---:|:---:|:---|:---|:---| | 1 | A | Glukosa 1% + Molisch + $H_2SO_4$ | Terbentuk cincin ungu kehitaman pada bidang batas antarmuka. | Positif Karbohidrat (Monosakarida) | | 2 | B | Sukrosa 1% + Molisch + $H_2SO_4$ | Terbentuk cincin ungu jelas pada bidang batas. | Positif Karbohidrat (Disakarida) | | 3 | C | Amilum 1% + Molisch + $H_2SO_4$ | Terbentuk cincin ungu (kadang disertai gumpalan gelap karbon). | Positif Karbohidrat (Polisakarida) | | 4 | D | Aquades + Molisch + $H_2SO_4$ | Tidak terbentuk cincin ungu. Larutan tetap bening atau kuning muda. | Negatif Karbohidrat | Include photographs of patches before/after acid addition

Additional Tips for a "Patched" Variation

• If "patched" means patch clamp or patch surface (e.g., biological membrane patch), then you are applying Molisch test to a lipid-carbohydrate patch – adjust the guide:
  Use patch of membrane containing glycoproteins → detect carbohydrate presence via purple color after α-naphthol/H₂SO₄.
• If "patched" refers to software patch (unlikely for a lab journal), ignore – but clarify with your instructor.

3.1 Reagents

• Molisch’s Reagent: A solution of α-naphthol in 95% ethanol.
• Test Solution: Sample suspected to contain carbohydrates.
• Concentrated Sulfuric Acid ($H_2SO_4$): Used as a dehydrating agent.