Arang aktif merupakan adsorben multifungsi, dapat menyerap spesi yang bermuatan positif seperti ion logam, molekul netral seperti I2 dan bermuatan negatif. Tujuan penelitian adalah membuat arang aktif dari limbah bambu yang berguna meminimalisir kandungan  logam timbal (II) dan krom (III) dari perairan. Pembuatan arang dilakukan secara konvensional menggunakan tong kedap udara dengan pemanasan selama 12 jam. Aktivasi arang dilakukan menggunakan tanur pada suhu 650oC selama 4 jam. Hasil penelitian menunjukkan bahwa aktivasi termal  menghasilkan arang aktif lebih baik dibandingkan tanpa aktivasi.  Arang yang diaktivasi dan tanpa aktivasi memenuhi SNI 06-3730-1995 tentang arang aktif teknis. Luas permukaan sebesar 494,8178 m2/g, keasaman permukaan sebesar 4,4426 mmol/g, dan kebasaan permukaan sebesar 3,4467 mmol/g. Kondisi optimum adsorpsi terhadap ion logam yaitu waktu kontak 24 jam dan pH 8 untuk Pb(II) dan pH 6 untuk Cr(III). Kapasitas adsorpsi arang aktif sebesar 3,9800 mg/g untuk ion Pb(II) dan 3,9766 mg/g untuk ion Cr(III).

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Gayam (Inocarpus fagiferus Fosb) is a tropical plant whose stem bark has been used as traditional medicine. This research aims to identify the flavonoides isolate from stem bark of gayam and identify the class of flavonoids compound as antioxidant. Extraction of 1000 g stem bark powder with 8500 mL of 96 % ethanol to yield 30 g concentrated ethanol extract. Partition of 15 g extract ethanol-water (7:3) with chloroform and n-buthanol to yield 1,5 g concentrated chloroform extract, 5,87 g concentrated n-buthanol extract and 5,63 g concentrated water extract. The flavonoids test using Wilstatter and Bate-Smith Matcalf reagent showed that n-buthanol and water extract contain flavonoids compounds. Antioxidant activity of flavonoids tested with DPPH method and lipid peroxide ammonium thiocyanate method showed that n-buthanol extract had antioxidant activity with IC50 of 24 ppm and n-buthanol extract has ability to inhibit the formation of lipid peroxide with inhibition value of 63,04 %. Separation of n-buthanol extract using thin layer chromatography preparative with chloroform as mobile phase and silica gel GF254 as stationary phase obtained four fractions. Flavonoids test showed that fraction F3 contained flavonoids compounds. FTIR analysis indicated that isolate had functional groups such as  -OH , C=O, C-O alcohol, C=C aromatic, C-H aromatic and C-H aliphatic. UV-vis spectra showed 2 peaks at ? 310 nm  and  261 nm which indicated flavonoids group of  isolfavone with hydroxyl groups at C-5 and  C-7. Antioxidant activity test with DPPH method showed that the isolate had antioxidant activity with IC50 of 1 ppm.

Cymbopogon nardus has the potential to be an essential oil, used for kitchen spice, cosmetics (aromatherapy), and cancer medicines which contains citrate, eugenol, citronellol, citronellal, geraniol, citronellyl acetate, geranyl acetate, beta-caryophyllene, limonene, and methyl eugenol. This study aimed to analyze the components of Virgin Coconut Oil (VCO) after heating and adding Cymbopogon nardus compared to commercial products. The method of making coconut oil was enzymatic and heated for about ten minutes. Analysis of VCO components after being heated and added citronella was carried out by using ultimate size difference, microscopic analysis, and Gas Chromatography-Mass Spectrometry compared with the commercial VCO product. The results showed that there was an intensity change in the similarity of ion fragments as well as microscopically and carbon content of more than 70%, hydrogen 10%. Separation of VCO components resulted in good separation among ethyl esters such as ethyl caprylate, ethyl laurate, and ethyl myristate detected for 30 minutes by gas chromatography and fragment ion similarity in mass spectrometry. Chemical components in commercial oils were lauric acid, ethyl laurate, glycerol tricaprylate, and vinyl decanoate.

Analisis kandungan logam Zn, Fe, dan Cu dalam susu formula dengan metode destruksi kering dan basah telah dilakukan. Konsentrasi logam dalam susu ditentukan dengan metode spektrofotometri serapan atom menggunakan kurva kalibrasi. Persentase perolehan kembali dari metode kurva kalibrasi terhadap ketiga logam menunjukkan hasil yang baik, masing-masing 95,13% untuk Zn; 100,83% untuk Fe dan 99,39% untuk Cu. Konsentrasi logam Zn, Fe, dan Cu dalam susu formula A, B, dan C dengan metode destruksi kering dan basah berturut-turut; sampel A yaitu 79,14 mg/kg; 78,37 mg/kg; 3,40 mg/kg dan 80,98 mg/kg; 78,83 mg/kg; 1,92 mg/kg, sampel B yaitu 58,65 mg/kg; 94,01 mg/kg; 3,87 mg/kg dan 57,73 mg/kg; 89,09 mg/kg; 2,77 mg/kg, serta sampel C yaitu 45,41 mg/kg; 76,16 mg/kg; 2,96 mg/kg dan 38,62 mg/kg; 60,53 mg/kg; 2,92 mg/kg. Kandungan ketiga logam dalam susu formula tersebut masih pada rentang standar kesehatan makanan.