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"The Robusta coffee flowers were analyzed for phytochemical composition and antioxidant activity. Flower powders at three different stages were extracted successively with hexane, dichloromethane and methanol, resulting in the extracts of varying yields (1.61-16.01%). All crude extracts were constituted of flavonoids, terpenoids and alkaloids. The methanol crude extracts exhibited the best antioxidant activity on both DPPH (EC50 0.03-0.13 mg/mL) and reducing power (EC50 0.19-0.46 mg/mL). It also contained the highest amount of total phenols (28.32-139.88 mg GAE/g extract)."

"Daun laban (Vitex pinnata L.) mengandung senyawa fenol dan flavonoid yang berpotensi sebagai antioksidan. Penelitian ini bertujuan menentukan kombinasi terbaik dari pelarut Natural Deep Eutectic Solvent (NADES) berbasis glukosa–poliol untuk mengekstraksi senyawa fenol dan flavonoid total secara efisien dan ramah lingkungan menggunakan metode Ultrasound Assisted Extraction (UAE). Tiga kombinasi NADES (glukosa–gliserol, glukosa–xilitol, glukosa–sorbitol) dievaluasi berdasarkan kadar fenol total (TPC) dan flavonoid total (TFC) menggunakan spektrofotometer UV-Vis. Kombinasi glukosa–gliserol (1:3) menghasilkan TPC dan TFC tertinggi dan selanjutnya dioptimasi kondisi ekstraksinya menggunakan Response Surface Methodology (RSM) terhadap variabel waktu, rasio pelarut-serbuk, dan persentase air. Kondisi optimum diperoleh pada waktu 20,7 menit, rasio 20 mL/g, dan penambahan air 40%, dengan hasil TPC 399,860 mg EAG/g simplisia dan TFC 133,399 mg EK/g simplisia. Sebagai pembanding, maserasi etanol 70% menghasilkan TPC 294,043 mg EAG/g dan TFC 122,133 mg EK/g simplisia. Aktivitas antioksidan ekstrak optimum tergolong sedang dengan nilai IC50 metode DPPH dan ABTS masing-masing 107,227 µg/mL dan 113,155 µg/mL, serta nilai FRAP 23,784 g FeSO₄ ekuivalen/100 g ekstrak. Hasil ini menunjukkan NADES-UAE lebih efektif mengekstraksi senyawa aktif dibanding maserasi etanol 70%.

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Laban (Vitex pinnata L.) leaves contain phenol and flavonoid compounds that have potential as antioxidants. This study aims to determine the best combination of glucose-glycerol-based Natural Deep Eutectic Solvent (NADES) to extract total phenol and flavonoid compounds efficiently and environmentally friendly using the Ultrasound Assisted Extraction (UAE) method. Three NADES combinations (glucose-glycerol, glucose-xylitol, glucose-sorbitol) were evaluated based on total phenol (TPC) and total flavonoid (TFC) content using spectrophotometer UV-Vis. The glucose-glycerol (1:3) produced the highest TPC and TFC and further optimized the extraction conditions using Response Surface Methodology (RSM) on the variables of time, solvent-powder ratio, and water percentage. The optimum conditions were obtained at a time of 20,7 minutes, a ratio of 20 mL/g, and the addition of 40% water, with a TPC of 399,860 mg EAG/g dried powder and a TFC of 133,399 mg EK/g dried powder. For comparison, 70% ethanol maceration resulted in TPC of 294,043 mg EAG/g dried powder and TFC of 122,133 mg EK/g dried powder. The antioxidant activity of the optimum extract was classified as moderate with IC50 values of DPPH and ABTS methods of 107,227 µg/mL and 113,155 µg/mL, respectively, and FRAP value of 23,784 g FeSO₄ equivalent/100 g extract. These results indicate that NADES-UAE is more effective in extracting active compounds than 70% ethanol maceration."

"Tomat (Lycopersicum esculentum) merupakan salah satu tumbuhan yang mengandung fitonutrien yang merupakan antioksidan, yang berkontribusi dalam menghasilkan efek protektif terhadap penyakit kronik, seperti kanker dan penyakit kardiovaskular. Di antara semua fitonutrien tersebut, polifenol mendapat perhatian khusus, disebabkan aktivitas antioksidannya yang besar dan konsumsinya yang paling banyak dalam diet.Pada penelitian ini, kandungan fenol total ditentukan dengan metode Folin-Ciocalteau. Homogenat tomat diekstrak dengan metanol 70% sebagai pelarut. Residunya dilarukan dengan metanol 50%. Dibuat pula larutan asam galat sebagai standar pengukuran dengan kadar 0; 0.5; 1.0; 2.5; 5.0 µg/mL. Kemudian, kedua larutan diuji absorbansinya dengan spektrofotometri dengan panjang gelombang 765 nm.Hasil kandungan fenol total tomat adalah 9,405 mgGAE/100g berat segar. Terdapat perbedaan hasil dengan penelitian sebelumnya yang dapat disebabkan oleh berbagai faktor, seperti faktor pertanian, masa penyimpanan sampel, dan varietas tomat. Tomat juga memiliki kandungan fenol total yang terendah d mengkudu dan jahe dari hasil penelitian lain yang menggunakan alat dan larutan penguji yang sama pada waktu yang bersamaan.

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Tomato (Lycopersicum esculentum) is one of the plants containing phytonutrients, which are antioxidants; which contribute in producing protective effect to chronic disease, such as cancer and cardiovascular disease. Among all the phytonutrients, polifenol gets more attention, because it has good activity of antioxidant and it is the most phytonutrient consumed in diet.In this study, total phenolic content is determined with Folin-Ciocalteau method. Homogenate of tomato is extracted with metanol 70% as a solvent. The residues is dissolved with metanol 50%. We also made gallic acid solution as a measurement standard with the level of 0; 0.5; 1.0; 2.5; 5.0 µg/mL. Furthermore, we test the absorbance of both solution with spectrophotometry with wave length 765 nm.The results of total phenol content assay is 12,325 mgGAE/100g fresh weight. There is differences between this result with other reseach before which can affected by many factors, such as cultivating, sample storage, and tomato`s varieties. Tomato also has the lowest total phenol content among non and ginger from other research that used the same tools and test solution in the same time."

"Pada penelitian ini dilakukan studi kasus proses penyisihan fenol dalam limbah cair dengan teknik ozonasi katalitik menggunakan GAC dan ZAL dalam reaktor unggun diam berpemutar. Perbandingan efektivitas penggunaan katalis pada teknik ozonasi katalitik ditinjau dari kuantitas radikal hidroksil, persesntase penyisihan fenol, neraca massa ozon, perubahan pH, serta karakteristik dan kemampuan adsorpsi katalis.Hasil penelitian menunjukkan bahwa GAC lebih unggul dari ZAL dalam menyisihkan senyawa fenol di limbah cair, baik melalui proses adsorpsi tunggal maupun dengan teknik ozonasi katalitik. Pada kondisi operasi yang sama, GAC memiliki kemampuan adsorpsi fenol yang lebih baik (persentase penyisihan fenol 60,86% dengan tingkat adsorpsi 1,302 mg/g) dibandingkan dengan ZAL (persentase penyisihan fenol 15,47% dengan tingkat adsorpsi 0,287 mg/g). Dalam larutan limbah bersuasana basa (pH ≈ 10), kombinasi ozon dengan GAC mampu menyisihkan fenol sebesar 88,94% dibandingkan ozonasi katalitik menggunakan ZAL hanya mampu menyisihkan fenol sebesar 50,97%.

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In this research, a case study of elimination process of phenol compounds in waste water by catalytic ozonation using GAC and ZAL in rotating packed bed reactor was examined. The effectiveness comparison of catalysts which used in ozonation catalytic is evaluated from quantity of hydroxyl radicals, percentage of phenol degradation, the mass balance of ozone, pH changes, catalyst`s adsorption capacity, and the changes of catalyst characteristics.

The results showed that GAC is better than ZAL to eliminate phenol compounds in waste water, either through a single adsorption process as well as catalytic ozonation technique. At the same operating conditions, GAC has better ability for phenol adsorption (percentage of phenol degradation about 60,86% with the rate of adsorption up to 1,302 mg/g) compared to ZAL (percentage of phenol degradation about 15,47% with the rate of adsorption 0,287 mg/g). In waste water with alkali solution (pH ≈ 10), combination of ozone with GAC capable to remove phenol by 88,94%, compared to use catalytic ozonation using ZAL that only capable to remove phenol by 50,97%."