cJun NH2 terminal Kinase (JNK) merupakan protein kinase family MAPK yang berperan dalam j alur pensinyalan penyakit metabolisme, salah satunya dalam regulasi faktor resiko obesitas. Penelitian in bertujuan untuk mengeksplorasi potensi asemanan dan glukomanan dalam menghambat JNK sebagai antidiabetes.metode pendekatan molecular docking digunakan untuk mengidentifikasi interaksi antara senyawa asemanan dan glukomanan terhadap protein JNK. Asemanan dan glukomanan berikatan di sisi aktif yang berbeda satu sama lain. Residu sisi aktif asemanan berada di close gate protein JNK, sedangkan glukomanan menunjukkan sisi aktif jalur ikatan inhibitor dari JNK. Asemanan dan glukomanan menghambat aktivitas JNK dengan berikatan di sisi non-katalitik dan diprediksi penghambatan protein JNK oleh kedua senyawa secara alosterik yang dapat merubah konformasi protein JNK. Selain itu, asemanan berikatan dengan kuat terhadap protein JNK dengan jenis ikatan hydrogen, interaksi hidrofobik dan elektrostatik dengan energi ikatan yang lebih rendah dari glukomanan -JNK. Penelitian disimpulkan bahwa senyawa asemanan dan glukomanan berpotensi sebagai antiobesitas dengan peranannya sebagai inhibitor terhadap protein JNK.

Porang tubers are an agricultural product from one of the endemic plants in Southeast and East Asia, which found in the Indonesian forest and is a vital source of glucomannan. The simple processing of porang tubers is made into chips, ground using mechanical milling followed by air fractionation. However, porang flour from mechanical milling still has high impurities, such as calcium oxalate more than 2% and not safe for human consumption. The polishing process using a centrifugal grinder is needed to remove impurities that still attached to the glucomannan cells by the friction principle. The purpose of this study was to investigate the effect of the polishing cycle on physicochemical properties of porang flour. The experimental design used polishing historical data and process was conducted in two replication. The results showed the polishing cycle had a significant effect (p < 0.05) on the glucomannan content, viscosity, degree of whiteness, calcium oxalate content, starch content, protein content, and fat content. The best of polished porang flour was obtained on the 5 times of polishing cycle based on multiple attributes calculations.

This study aimed at investigating the effects of polishing conditions on the physicochemical properties of polished yellow konjac flour (PYKF) with a centrifugal mill using Central Composite Design-Response Surface Methodology (CCD-RSM). Micro-mill milled yellow konjac flour (MMYKF) mass and polishing cycles were the independent variables, with four observed responses (calcium oxalate, viscosity, degree of whiteness (DoW), and glucomannan). The lower limit (-1) and upper limit (+1) for MMYKF mass in this study are 10 and 15 kg, respectively, while the -1 and +1 for the polishing cycle are three times, and seven times, respectively. The optimum prediction occurred at 10 kg of MMYKF mass and six times the polishing cycle with the following characteristics: 0.52 ±0.00% w.b. calcium oxalate, 20362.00 ±16.00 cP viscosity, 62.22 ±0.01 DoW, and 69.43 ±0.02% d.b. glucomannan content, which agreed with the verification data with p-value >0.05 for all observed responses using the paired T-test. Polishing using a centrifugal mill is feasible and promises to be scaled up to industrial scale for yellow konjac flour polishing before the wet extraction process.

Polished yellow konjac (Amorphophallus muelleri Blume) flour (PYKF) from the centrifugal milling process still contains a relatively high level of impurities that may be harmful to health, especially calcium oxalate. The extraction process using ethanol is needed to reduce the amount of impurities surrounding the glucomannan granules and hence to improve the purity of the latter. This study was aimed at determining the effects of process conditions including ethanol concentration, solvent to flour ratio and extraction time on the physicochemical properties of purified yellow konjac flour (PrYKF) using Response Surface Methodology. The desired characteristics of PrYKF were low calcium oxalate content and a high degree of whiteness (DoW), viscosity, and glucomannan content. The calcium oxalate content, viscosity, and glucomannan content of PrYKF were affected by ethanol concentration, solvent to flour ratio, and extraction time. In contrast, the DoW was only affected by ethanol concentration. The prediction of the optimum condition by Design-Expert was found at 46.36% of ethanol concentration, 8.33 mL/g of solvent to flour ratio, and 63.01 mins. Under these conditions, the characteristics were as follows: 0.12±0.00%w.b. calcium oxalate, 68.76±0.00 DoW, 29012±0.00 cP viscosity, and 84.59±0.00% d.b. glucomannan content. The actual verification was closely related (p > 0.05) compared to the Design-Expert software prediction by paired t-test. The fast maceration is a successful method to improve the characteristics of PYKF to PrYKF in a shorter time.

Persicaria odorata (Synonym of Polygonatum odoratum and Polygonum minus) leaves, locally known as Kesum leaves, is one of Indonesia's biodiversity species, particularly on Kalimantan Island, and it is contained a high concentration of essential oils. The extraction of essential oil from Kesum leaves commonly uses various methods, including solvent extraction, steam distillation, hydro-distillation, supercritical fluid extraction, microwave-assisted extraction, ultrasonic-assisted extraction, and so on, with various extract characteristics produced. Several studies reported that Kesum leaves essential oil has numerous advantages, including anti-bacterial, hepatoprotective, anti-tyrosinase, antioxidant properties, and so on. Future research will require additional and new techniques, particularly non-thermal extraction technology and other bioactivity tests, to improve yield and maintain the essential oil composition of Kesum leaves.