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Cellulose-based advanced materials, such as cellulose nanocrystals (CNC), have high potential application for drug delivery system. In this study, the CNC were produced from bamboo shoots using acid hydrolysis process. The delignification of bamboo shoots was conducted using alkali and hydrogen peroxide pretreatment processes. The operating condition of the production of CNC from bamboo shoots was optimized using Response Surface Methodology (RSM) based on the yield and crystals recovery as the responses. The optimum CNC yield of 50.67 ± 0.74% with a crystals recovery of 77.99 ± 1.14% was obtained at the sulfuric acid concentration of 54.73 wt% and a temperature of 39 °C from the optimization based on the yield. This optimization has been validated to confirm the accuracy.

Due to their biocompatibility, biodegradability, and non-toxicity, lignocellulosic-derived nanoparticles are very potential materials for drug carriers in drug delivery applications. There are three main lignocellulosic-derived nanoparticles discussed in this review. First, lignin nanoparticles (LNPs) are an amphiphilic nanoparticle which has versatile interactions toward hydrophilic or hydrophobic drugs. The synthesis methods of LNPs play an important role in this amphiphilic characteristic. Second, xylan nanoparticles (XNPs) are a hemicellulose-derived nanoparticle, where additional pretreatment is needed to obtain a high purity xylan before the synthesis of XNPs. This process is quite long and challenging, but XNPs have a lot of potential as a drug carrier due to their stronger interactions with various drugs. Third, cellulose nanocrystals (CNCs) are a widely exploited nanoparticle, especially in drug delivery applications. CNCs have low cytotoxicity, therefore they are suitable for use as a drug carrier. The research possibilities for these three nanoparticles are still wide and there is potential in drug delivery applications, especially for enhancing their characteristics with further surface modifications adjusted to the drugs.

Because of their hydrophilic tendencies, the modification of cellulose nanocrystals (CNCs) is needed for applying them as a hydrophobic drug carrier. Previous studies have investigated several modification agents, such as cetyltrimethylammonium bromide. Natural surfactants, such as rarasaponins (RSs), are suitable to avoid human health and environmental issues. In this work, RSs were attached onto CNCs from bamboo shoots to enhance their hydrophobicity. The initial RS concentration and the operating temperature were studied to obtain the best conditions for the modification process, which had significances ( p -value < 5%) toward the amount of RSs linked on the CNCs ( q ) as the response. A q as high as 203.81 ± 0.98 mg/g was obtained at an initial RS concentration of 2000 mg/L and an operating temperature of 30 °C. The curcumin uptake on CNCs-RSs reached 12.40 ± 0.24%, while it was slowly released until approximately 78% in 3 days.

Due to its excellent characteristics, zeolitic imidazole framework-L (ZIF-L) is widely used in various applications, such as drug delivery, wastewater treatments and energy storage. In the synthesis of ZIF-L, the molar ratio of ligand to metal, the reaction time and the temperature are essential parameters to produce excellent ZIF-L. In this work, ZIF-L was synthesized using a facile and green synthesis method. It was statistically investigated and optimized to obtain the best operating conditions. The optimization was carried out toward the amount of adsorbed crystal violet (CV) dye (q) as the response in the statistics. The optimal ZIF-L was obtained using a molar ratio of ligand to metal of 8.2220 for 97 min at 29 °C, where the q value of the CV adsorption onto this optimal ZIF-L reached 823.02 mg/g. The obtained ZIF-L was characterized using SEM, XRD, FTIR and TGA analyses to ensure its excellent characteristics.

Calophyllum inophyllum or commonly called nyamplung in Indonesia has the potential to be used as a biodiesel feedstock due to its high oil content. The purpose of this study was to determine the effect of feed flowrate and solvent to oil mass ratio on triglycerides (TAG) and free fatty acid (FFA) contents in non-polar lipid fraction (NPLF) of C. inophyllum seed oil by using continuous counter-current extraction. The contents of TAG and FFA in NPLF of C. inophyllum seed oil each sample points in continuous countercurrent extraction equipment. It was expected that the TAG became purer and suitable for biodiesel purpose. Various factors applied in this study were the effect of solvent to oil mass ratio and the effect of n-hexane + oil to methanol feed flowrate in liter per hour. Crude C. inophyllum seed oil contained 63.91% TAG, 15.76% FFA, 12.25% monoglycerides (MAG), dan 4.66% diglycerides (DAG). Separation and purification of TAG were carried out by using a packed column with the principle of countercurrent flow using n-hexane and methanol technical grade as solvents. The product of extraction analyzed TAG content qualitatively by using TLC and quantitatively using HT-GC, while NPLF from each sample points were analyzed using HT-GC. The optimum results were obtained by using a solvent to oil mass ratio of 6 (w:w) and (n-hexane + oil) to methanol feed flowrate of 6:15 (L/h:L/h) with 92.85% content of TAG, 2.19% content of FFA and 74.79% yield of NPLF.

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To promote a minimal use of acid in the activation of bentonite and to maintain oil quality during refinery and storage, a new class of bleaching agent, cetyltrimethylammonium bromide (CTAB)-pillared bentonite (CTAB@Bent), is fabricated. The influences of three independent intercalation variables, including temperature T (40, 50, and 60 °C), time t (2, 4, and 6 h), and CTAB loading m c (0.2, 0.25, 0.33, 0.50, and 1.00%, w/w), on the β-carotene removal rate are studied. The multilevel factorial design combined with the response surface methodology and three-way analysis of variance is employed to design and optimize experiments in regard to the three independent variables. Based on the optimization results, the highest β-carotene removal rate is monitored at 71.04% (w/w) using CTAB@Bent obtained at optimum intercalation conditions (CTAB@Ben-Opt): T = 40 °C, t = 3.2 h, m c = 1.00% (w/w). The mechanism study shows that the adsorption of β-carotene onto CTAB@Bent-Opt is spontaneous and endothermic, with the governing steps of physical interaction and ion exchange between β-carotene and the cationic head of CTAB. CTAB@Bent-Opt also exhibits characteristics superior to those of commercial raw bentonite and acid-activated bentonite, indicating that a more efficient β-carotene removal can be achieved using this new bleaching agent.