Key Engineering Materials Vol. 840

Abstract: The research of adsorption of Cu²⁺ metal ion on dithizone-immobilized natural bentonite (DNB) had been carried out. The experiment was begun by the activation of natural bentonite with HCl 4 M and dithizone-immobilized on activated bentonite surface. This study included synthesis and characterization of dithizone-immobilized bentonite and its application in adsorption of Cu²⁺ metal ions. The type of interaction occurred in the adsorption was tested by sequential desorption. The result showed that dithizone successfully immobilized on activated natural bentonite (ANB). The optimum conditions for Cu²⁺ metal ions adsorption using dithizone-immobilized natural bentonite are at pH 5; 0.1 g mass of adsorbent, with interaction time 60 min, and the initial concentration of ion at 80 ppm. Kinetics and adsorption isotherm studies suggest that the capacity, of the dithizone-immobilized natural bentonite in adsorbing Cu²⁺ metal ion is significantly improved compared to activated natural bentonite. The adsorption of Cu²⁺ metal ions by activated natural bentonite was through several interactions dominated by electrostatic interaction (82%). Otherwise, the interaction of dithizone-immobilized natural bentonite with Cu²⁺ metal ions in the sequence were dominated by the mechanism of complex formation of (75%). The result shows that the immobilization of dithizone changes the type of electrostatic interaction into complex formation.

Abstract: Photocatalysis is a promising solution for the degradation of dyes since this substance give a negative impact on the environment. In this study, Ni_0.5V_0.5Fe₂O₄ nanophotocatalyst was prepared simultaneously using sol-gel and freeze-drying methods. After the freeze-drying process, the sample was subjected to calcination treatment and subsequently characterized using the techniques of X-ray Diffraction (XRD) and Scherrer calculation method, FTIR, DR spectroscopy, and TEM analysis. The results of XRD characterization indicated that material consists of Ni_0.5V_0.5Fe₂O₄ spinel as a major crystalline phase. Then, TEM analysis proved that the grain size of this spinel is in the range of 20 nm. Crystallite size calculation using Scherrer equation proved that the size is 34.06 nm, DRS analysis indicated that bandgap energy of spinel Ni_0.5V_0.5Fe₂O₄ is suitably utilized and FTIR spectra analysis implied that the prominent acid sites are Lewis acid. Furthermore, results of dyes photodegradation indicated that Ni_0.5V_0.5Fe₂O₄ nanocatalyst is active for remazol golden yellow degradation until 45% conversion under sunlight irradiation for 100 min.

Abstract: The TiO₂/Fe₃O₄ nanoparticle has been successfully synthesized and the material is then applied as a photocatalyst to reduce Pb(II). The Fe₃O₄ was synthesized through sono-coprecipitation method using NH₄OH as a precipitating agent. The coating TiO₂ onto Fe₃O₄ was performed respectively via hydrolysis reaction and sol-gel process using ammonium sulfate and TTIP as a reagent of TiO₂. This study investigated several parameters such as the effect of time, equilibrium state and material responsiveness toward ultraviolet light. The XRD measurement indicated the presence of Fe₃O₄ and TiO₂ while TEM image displayed the photocatalyst had a nanosized particle with approximately 60 nm in size. An activity test at pH 4, the equilibrium of photoreduction process showed at 60 minutes. The kinetic parameter of Pb(II) reduction at various catalyst presented that TiO₂/Fe₃O₄ nanoparticle had better reduction rate constant than that of TiO₂. Reusing of TiO₂/Fe₃O₄ photocatalysts showed the results of Pb (II) photoreduction were not significantly decrease and the results of photocatalysis were still better than TiO₂.

Abstract: Pectin is a derivative polysaccharides biopolymer that can be used as a material for an edible film. In this study, pectin edible film was made from a thin layer of edible pectin. The physical properties of the edible films such as elongation of the break, tensile strength, and the swelling degree were observed when carbonate hydroxyapatite (CHA) was added to the pectin edible film. In order to study the loading and release behavior of the pectin edible film, cinnamaldehyde (2 wt%) was also added to the film used as a drug sample. Cinnamaldehyde is known as a derivative compound of cinnamon bark. The edible film was made by mixing pectin (0.015 g/mL) and carbonate hydroxyapatite (CHA). Various concentration of carbonate hydroxyapatite (1, 3, 5, 7 wt%) was diluted in water and stirred using tween 80 and glycerol for about 1.5 h at a temperature of 70 °C. Then, cinnamaldehyde was added to the mixture and stirred for 30 minutes. The mixture was dried in an oven at a temperature of 50 °C for 15 h and stored in the desiccator. The experiment results showed that the tensile strength of pectin edible film was increased when more concentration of CHA added to the film, but the elongation of break and swelling were decreased. These results indicate that the addition of carbonate hydroxyapatite (CHA) affects the properties of pectin edible film significantly but does not affect the thickness of the film.

Abstract: Bioethanol is considered as the most promising prospective renewable energy source. One of the most potential lignocellulose material for bioethanol feedstock is spent media (SM) of edible mushroom. Pleurotus ostreatus is more selective to degrade lignin than holocellulose component, therefore the SM is very compatible as a bioethanol feedstock. This study was observed the influence of variation of cultivation time of oyster mushroom (P.ostreatus) into the SM chemical content and its ethanol production yield by using simultaneous saccharification and fermentation method. The results showed that the difference of cultivation time did not show the significant result on SM chemical content, except the hot water soluble extractive content. The highest hot water soluble extractive content was found in SM with 110 days of cultivation time (27.68%). The highest hydrolysis rate was found at 90 days of cultivation time (15.65%) and 48 and 72 hours saccharification time (14.77% and 14.78%). The highest reducing sugar content was found at 110 days of cultivation time (4.89 g/L). The highest ethanol content was found in SM with a combination of 90 days cultivation time and 48 hours saccharification time (1.696 g/L). The 90 days cultivation time was enough to produce SM that can be used as raw material for bio-ethanol production.

Abstract: Inulinase is an enzyme that catalyzes the reaction involving the hydrolysis of inulin into fructose and/or small fructooligosaccharides by cutting the β-2,1 terminal. The present study aimed to determine the inulolytic activity of extracellular inulinase, extracted from L. casei AP, when grown under different conditions. Extracellular inulinase was extracted from the growth supernatant of L. casei AP, following which the extract was subjected to the qualitative inulinase test; inulinase activity was determined under growth conditions involving different combinations of pH and temperature. The results showed that L. casei AP had inulinolytic ability; therefore, it degraded inulin both in inulin media and inulin extract. The optimum activity of inulinase occurred at the combination of a temperature of 41 °C and pH of 5, with the activity of 20.53 in inulin media and 17.73 in inulin extract.

Abstract: Twenty goats were given a basal feed of Pennisetum purpureum cv Mott (odot grass) and supplemented with protein-based feed ingredients namely calliandra calothyrsus and soybean meal (SBM). The proportion of calliandra feed substitution and soybean meal is T1 = odot grass (ad libitum) + 100% soybean meal; T2 = odot grass (ad libitum) + 25% calliandra + 75% soybean meal; T3 = odot grass (ad libitum) + 50% calliandra + 50% soybean meal; T4 = odot grass (ad libitum) + 75% calliandra + 25% soybean meal; and T5 = odot grass (ad libitum) + 100% calliandra. The amount of feed supplementation given is based on daily protein requirements (gram/DM) per day according to animal body weight. The feed given contained iso protein (CP) and iso energy (TDN) to determine the effect of substitution of soybean meal with calliandra The parameters observed were intake and nutrient digestibility of feed. Data obtained from the results of the study analyzed variance using a one-way analysis of variance, then if the results show significant differences, it will be analyzed further with Duncan's new multiple range test. The results showed that substitution of calliandra did not have a significant effect (P> 0.05) on nutrient intake (g/kg BB^0,75/day), except for intake of ETN, it shows a significant effect (P< 0.05). Calliandra substitution had a significant effect (P<0.05) on feed nutrient digestibility, with the highest digestibility being T2 treatment (25% calliandra substitution).

Abstract: Synthesis of 4-(5-bromo-4-hydroxyphenyl-3-methoxy)-2-butanone and its potential test as fruit flies attractant has been done. All of products were analyzed by FT-IR GC-MS, and ¹H-NMR. Synthesis of 4-(5-bromo-4-hydroxyphenyl-3-methoxy)-2-butanone was carried out in three steps reaction. First, the bromination of vanillin was performed using KBrO₃ and HBr in acidic condition. Second, aldol condensation of 5-bromovanillin with acetone using base catalyst NaOH 20%. Third, 4-(5-bromo-4-hydroxyphenyl-3-methoxy)-2-butanone was synthesized by reacting the reduction reaction of condensation aldol products with NaBH₄ and NiCl₂.6H₂O in methanol solvent in mild condition. Based on FT-IR, GC-MS and ¹H-NMR analyses, the synthesis of 4-(5-bromo-4-hydroxyphenyl-3-methoxy)-2-butanone has been successfully by selective hydrogenation reaction with 68% yield. Testing the result as attractant of fruit fly indicated that synthesized compound can be used as attractant.

Abstract: The aim of the study was to evaluate the use of Calliandra leaves (Calliandra calothyrsus) as a protein source in the Kacang goat’s diet and as an alternative to substitute the use of soybean meal (SBM) in goat’s diets. The proportion of C. calothyrsus feed substitution and SBM is T1 = odot grass (ad libitum) + 100% SBM; T2 = odot grass (ad libitum) + 25% C. calothyrsus + 75% SBM; T3 = odot grass (ad libitum) + 50% C. calothyrsus + 50% SBM; T4 = odot grass (ad libitum) + 75% C. calothyrsus + 25% SBM; and T5 = odot grass (ad libitum) + 100% C. calothyrsus. The last 10 days, collections was conducted include total collections of feeding, the residue of the feed, and feces. The parameters observed were intake and nutrient digestibility of dry matter (DM), crude protein (CP), neutral detergent insoluble nitrogen (NDIN) (% CP), and acid detergent insoluble nitrogen (ADIN) (% CP). Data obtained from the study were analyzed using a one-way analysis of variance, then if the results show significant differences, it will be analyzed further with Duncan's new multiple range test. The results showed that C. calothyrsus substitution treatment of 25 to 100% (T2, T3, T4, T5) gives noticeable influence (P<0.05) for nutrient intakes, excretion (feces), and digested nutrients. The highest intake and digestible fraction of N-NDF, N-ADF, NDIN, and ADIN is the T5 treatment, which is the replacement of SBM with 100% C. calothyrsus (P<0.05).

Abstract: The distribution of root and bulb parasitic nematode in garlic crops at various elevation and the effect of abiotic factors on their distribution were investigated. The survey was done at the centers of garlic production area in Central Java, Indonesia. Soil abiotic factors such as temperature, pH, and C-Organic were measured in each location of sampling. Nematodes were analyzed using incubation and white head tray technique modification. Correlation and regression were used to determine the effect of abiotic factors. The results showed that the five locations with different elevations were positive for Ditylenchus dipsaci distribution. These nematodes were found in various elevation with different populations in the range of 8.00-16.67 nematodes per 100 g of soil and 14.34 to 26.67 nematodes per 2 g of bulb. The highest density of the nematode population both in bulb and soil was in Tegal at elevation <1000 m a.s.l. while the lowest nematode population both in soil and root were found in Temanggung at an elevation of 1000-1200 m a.s.l. Abiotic factors, such as temperature has a positive correlation with D.dipsaci nematode populations in bulb and soil, while pH has a negative correlation with nematode populations. C-organic has a positive correlation in abundance of nematode populations in the soil and negative in abundance of nematode populations in bulb.