Garlic waste—including straws, bulbs, and skins—is an agricultural residue contributing to household waste. Rich in cellulose, garlic waste can be converted into various value-added products through proper processing. In this study, cellulose was extracted from garlic waste using alkaline treatment to investigate the influence of sodium hydroxide (NaOH) concentration on the characteristics of the resulting cellulose. NaOH solutions with varying concentrations of 2%, 7%, 14%, and 20% were used during the alkalization process. FTIR spectra revealed transmittance changes with increasing concentration, indicating a reduction in lignin content. The resulting cellulose exhibited needle-like structures, and garlic fibers with amorphous morphology showed cleaner surfaces at a NaOH concentration of 20%. The highest extract yield from the alkalization process was 62.7%, achieved at a NaOH concentration of 2%. These findings demonstrate the potential of garlic waste as a cellulose source and its applicability for producing derivative products such as thin films, optical fibers, and bioplastic raw materials.

Rice bran oil (RBO) is a by-product of rice processing with a good fatty acid profile and high oxidative stability. This study aims to optimize the bleaching stage of the rice bran oil refining process to determine the minimum levels of carotenoids in RBO by using the Response Surface Methodology (RSM). This research used the Central Composite Design (CCD) experimental design with three variables: bleaching temperature (50, 80, 1100C), bleaching time (20, 40, 60 minutes), and activated carbon concentration (0.4, 0.8, 1.2%). As a result, the model was enhanced to explain the correlation of each variable and the different data variations. This study employed the Derringer method to determine the most optimal variable variation that produces the lowest carotene levels. This study found that the optimal carotene level was 4.87 mg/kg with an activated carbon concentration of 1.18%, temperature of 500C, and time of 53.155 minutes.

The daily abundant generation of fruit peel waste potentially triggers environmental problems if no appropriate management is performed. Besides, fruit peel waste can be a valuable source for functional enzyme production. This study aims to investigate the use of molasses and palm sugar as sugar source during anaerobic fermentation of banana and papaya peel waste to produce functional enzymes. The fermentation was subjected to biomass at various banana peels to papaya peels mass ratio for 3 months. The feed consisted of sugar:biomass:water, and their mass ratio was kept constant at 1:3:10. Both brown functional enzyme cocktails obtained from the fermentation using palm sugar and molasses as carbon source were acidic with pH of 3.7 and 4.4, respectively. The amylase, protease, and lipase activities of the functional enzyme cocktails was maximum when the biomass mixture contained four portions of banana peel and one portion of papaya peel. In addition, molasses was found to be the better sugar source than palm sugar for producing functional enzymes from aerobic fermentation peel fruits comprises banana and papaya peels. This study proved that fruit peel waste can be converted to valuable functional enzymes as one of the solutions of fruit peel waste management Keywords: anaerobic fermentation; carbon source; enzyme activity; functional enzyme; organic waste

The body needs antioxidants to combat free radicals and guard against their damaging effects on healthy cells that might result in degenerative disorders. Several degenerative diseases include hypertension, heart disease, diabetes, stroke, and cancer. The human body can deal with free radical attacks caused by radiation, stress, cigarette smoke, and environmental pollution, so it requires additional external antioxidants to protect against free radical attacks. Chalcone is a compound that has an α,β-unsaturated carbonyl system, which makes chalcone compounds have biological activity. Chalcone compounds may be used in pharmacology as antioxidants, antifungals, antibacterial agents, anticancer agents, and for other biological activities. This study aims to synthesize a chalcone derivative, namely 3-(2-oxo-2-phenylethylidene)indolin-2-one and 5-chloro-3-(2-oxo-2-phenylethylidene)indolin-2-one containing a chloro substituent, as well as test the potential of these compounds as antioxidants. The reflux method of claisen-schmidt condensation of isatin and acetophenone was used to create chalcone derivatives. Spectroscopy was used to characterize the produced chemicals (UV-VIS, IR, and LCMS) and their antioxidant activity using the DPPH method. This study showed that the antioxidant activity of 3-(2-oxo-2-phenylethylidene)indolin-2-one and 5-chloro-3-(2-oxo-2-phenylethylidene)indolin-2-one compounds is very weak at low concentrations.

Health and environmental problems related to plastic food packaging are general problems. Edible film as food packaging from organic and edible materials can be a solution by increasing its structure and content. Modification of edible film from the protein of Velvet bean (Mucuna pruriens) with gelatin and alginate to modify the structure of the film and the addition of green tea leaf extract as an antioxidant. Edible films are made by combining constituent materials with the addition of a crosslink method. The addition of green tea leaf antioxidant concentration on nutritional properties, chemical properties, and shelf life of edible films through the DPPH method and antimicrobial tests showed good changes. The addition of gelatin, alginate, and green tea leaves to the mechanical and morphological properties of the film showed good indications. The effect before and after the addition of green tea leaves on the chemical structure of the edible film (OH‑ group) using FTIR analysis shows indications through changes in spectra. Modified velvet bean film with gelatin, alginate, and green tea leaves can potentially be applied in the food industry as food packaging.

Red cabbage and white cabbage contain several beneficial compounds, such as anthocyanins that can scavenge free radicals. The study aimed to determine the effect of drying on anthocyanin content and antioxidant activity in red cabbage and white cabbage. Each cabbage will be given two pretreatments, namely: (1) drying, and (2) without drying. Maceration extraction using a mixture of water and methanol 50:50 (v/v) acidified with 7% citric acid with a liquid to solid mass ratio of 1:4 (w/v) and with a controlled temperature of 60°C for a period of 1 h. Cabbage extract was examined for anthocyanin content by differential pH method and antioxidant activity was tested by DPPH method. The results showed anthocyanin content in crude fresh red cabbage extract 64.124 mg/L, crude dried red cabbage extract 210.74 mg/L, crude fresh white cabbage extract 0.445 mg/L, crude dried white cabbage extract 0.584 mg/L. The antioxidant activity (IC50) of crude fresh red cabbage extract, crude dried red cabbage extract, crude fresh white cabbage extract, and crude dried white cabbage extract were 54,317 ppm, 49,464 ppm, 131,878 ppm, and 107,069 ppm, respectively. The optimum results were crude dried red cabbage extract with a yield of 25.2%, anthocyanin content of 210.74 mg/L, IC50 value of 49.464 ppm.

TiO2 nanoparticles, a semiconductor photocatalyst is widely used in various applications especially for water treatment. The common problems for the application are separating the nanoparticles from the water body and recovering it to be reused. This research was conducted to investigate the aggregation and sedimentation properties of TiO2 nanoparticles via chemical addition. The experiment was carried out for 5 hours by varying the pH, ionic strength, and the addition of organic matter such as rhodamine B, methylene orange, and humic acid. The results indicate that pH and ionic strength greatly affect the TiO2 sedimentation process. Sedimentation can be formed properly when the solution is at pH 1 and 14, this happens because pH is close to the isoelectric point. Meanwhile, ionic strength with a concentration of 0.1 M gave the most optimal results in TiO2 sedimentation. In the presence of ionic strength with the appropriate concentration, the thickness of the electrical double layer particles can be reduced so the attractive force increases and sedimentation occur. Meanwhile, in the presence of organic matter, rhodamine B, methylene orange, and humic acid did not significantly affect the formation of TiO2 sedimentation.Keywords: titanium dioxide, sedimentation, ionic strength, isoelectric point, water treatment

Lemongrass (Cymbopogon citratus) is a medicinal plant with various biological activities such as antibacterial, antifungal, antiprotozoal, anti-inflammatory, and antioxidant. This study aimed to encapsulate lemongrass bioactive in alginate/chitosan complex by enhancing the properties of CaCl2 crosslinked incorporated with tween 80 by ionic gelation method. The hydrogel was prepared by mixing alginate solution (2% w/v) and chitosan solution (1% w/v) with a ratio (1:1 v/v). Tween 80 (2% v/v) was added as a dissolution enhancer and CaCl2 as a crosslinker agent. The formulation varying by concentration of CaCl2 (0.1M to 0.3M) and lemongrass extract (2% to 12%). Encapsulation lemongrass with alginate-chitosan beads is characterized to determine encapsulation efficiency, swelling study, morphology, functional groups, and release study. The results showed that encapsulation efficiency ranged from 74.81% to 83.07%. Encapsulation efficiency increased with the addition of CaCl2 and lemongrass extract concentration. The swelling ratio ranged from 27.29 to 37.81, it will decrease with the addition of CaCl2 and lemongrass extract concentration. The Scanning Electron Microscopy (SEM) analysis of hydrogel beads shows a polyhedral shape, porous, and rough surface which indicates bioactive of lemongrass trapped on the beads. The Fourier Transform Infrared Spectroscopy (FTIR) results show new peaks at 1734 cm-1 as carbonyl stretch vibrations in ketones, aldehydes, and carboxylic acids, indicating the addition of lemongrass extract. Bioactive of lemongrass extract loaded alginate-chitosan beads was successfully released as much as 87.12% at pH 6.8. This study suggested the strong potential alginate-chitosan beads as an encapsulating agent for lemongrass extract using the ionic gelation method, and it has potential as a drug delivery system.Keywords: encapsulation; lemongrass; alginate; chitosan; CaCl2

Chitinolytic mold, such as Mucor circinelloidesis can be utilized to produce chitinase enzyme for shrimp shell’s chitin hydrolysis into N-acetylglucosamine (NAG). For that purpose, entrapment of chitinase on agar as a carrier could be an alternative way to improve NAG production. This study aimed to investigate the stability of immobilized semi-purified chitinase on agar for multiple cycles fermentation to produce NAG. In this study, 0.6 mL of semi-purified chitinase enzyme was immobilized into 3% of agar matrices and tested for four fermentation cycles to obtain highest NAG concentration and good enzyme activity. The results indicate that the immobilized chitinase could be used for 6 hours fermentation or three fermentation cycles. The NAG concentration produced after three cycle were 1042.22 ± 16.20 ppm. Besides, the immobilized enzyme was considerably stable up to the third cycles with activity value of about 4.74 U/mL.Keywords: agar; immobilized;NAG; repeated fermentation

The chemical composition of potatoes includes carbohydrates, protein, fiber, vitamins, and minerals. The composition of vitamins and minerals in potatoes is higher than wheat flour. Brownish color in potato flour has reduced consumer's interest, so it needs to be modified to improve the color and physicochemical properties of flour. Researchers are trying to modify the blanching process using hydrogen-rich water. Because hydrogen-rich water has antioxidants that can prevent the browning process (oxidation) potato flour, cheaper, safer, and healthier than chemical compounds. The purpose of this study was to optimize the blanching process for potato flour modification. Variation of the process used is soaking time at 30, 45, 60, 75, and 90 minutes. The optimal results of water content, ash content, reducing sugar content, protein, color, and swelling power were obtained at 75 minutes are 6.7%, 2.68%, 0.26%, 7.1%, 81.17, and 7 g/g. The quality of the modified potato flour met the physicochemical parameters of the flour according to the SNI standard for flour, except ash content. The quality of potato flour produced almost equals as the quality of wheat flour, so it needs to be considered as a substitute for wheat flour and is friendly for diabetics.Keywords: potatoes, modified flour, physicochemical properties, wheat