Struktur Dan Komponen Arang Serta Arang Aktif Tempurung Kemiri

Cara aktivasi arang menentukan kekhususan penggunaan arang aktif yang dihasilkan. Secara umum dikenal dua cara aktivasi arang untuk menghasilkan arang aktif yaitu cara fisika dan kimia. Penelitian ini bertujuan untuk mengetahui struktur dan komponen penyusun arang dan arang aktif tempurung kemiri. Tempurung kemiri dikarbonisasi menggunakan tungku drum untuk menghasilkan arang, selanjutnya arang diaktivasi di dalam retort listrik menggunakan aktivator panas selama 120 menit pada suhu 550C, 650C, dan 750C dan aktivator uap air selama 90 dan 120 menit pada suhu 750C. Sampel uji tempurung kemiri, arang dan arang aktif dikarakterisasi strukturnya yang meliputi gugus fungsi, kristalinitas dan porositas dengan menggunakan Fourier Transform Infra Red (FTIR), X-Ray Difractometer (XRD) dan Scanning Electron Microscope (SEM). Selain itu, senyawa kimia masing-masing sampel uji diidentifikasi menggunakan Pyrolisis Gas Chromatograph Mass Spectrometer (Py-GCMS) Hasil mengindikasikan bahwa proses aktivasi menyebabkan terjadinya Perubahan pola gugus fungsi, peningkatan kristalinitas, pembukaan pori dan reduksi senyawa kimia. Semakin tinggi suhu aktivasi diikuti oleh peningkatan kristalinitas, diameter pori dan reduksi senyawa kimia arang aktif. Aktivasi menggunakan uap air menghasilkan arang aktif dengan pori yang relatif lebih bersih

Biological Activities Afforded by the Extract From Raru Bark to Inhibit Action of Alpha- Glucosidase Enzymes

Raru (Shoreabalanocarpoides Sym) signifies one of the tree species that grows widespread in Sumatra Island. Its bark portion is commonly used by local villagers as additional ingredient mixed to nira (sugar palm juice). This addition is intended to make the juice more durable and also to enrich its taste after the juice is previously fermented to become traditional toddy beverage or the so-call “tuak”. Local villagers believe that raru bark can reduce the level of blood sugar. As the relevance, the research was conducted to confirm that the extract from raru bark could afford its biological activities to inhibit alpha-glucosidase enzyme through its characterization, quantification, and isolation of its boactive compound. The extraction was performed using two methods (i.e.reflux and maceration techniques). Result revealed that the bark extract obtained from both techniques contained polyphenol compounds: flavonoid, saponin and tannin. Further, raru-bark extract from the reflux and maceration techniques could inhibit the action of alpha glucosidase enzymes on carbohydrate substrate ( i.e. p -nitrophenil-α-D-glucopyranose), at respectively 90.67% and 97.33%. Meanwhile, the inhibition activities afforded by the patented drug as a control (i.e. glucobay) equaled to 97.05%. Assesment using UV-VIS spectroscopy, showed that the maximum spectrum of bioactive compound in the extract was at the wave length of 288.6 nm. Scrutiny using FTIR spectroscopy could identif y the presence of aromatic groups in the compound, containing -OH, C-H, C=C, C-O and C-H bond types. Analysis using GC-MS exhibited that the compound had molecular weight of 390 with molecular structure as C20H22O8. Ultimately, data analysis scrutiny with the aid of NMR judged the most plausible compound as bioactive was 4-Glucosyl-3, 4', 5-trihydroxystilbene

Lignin and Cellulose Changes of Betung Bamboo (Dendrocalamus asper) pretreated Microwave Heating

This study highlighted the effect of microwave pretreatment on betung bamboo on the chemical structural and morphological changes. The hydrothermal condition was performed in varying power loading (330, 550, and 770 W) and microwave irradition time (5-12.5 min). FTIR spectroscopy, X-Ray diffraction and SEM-EDS analysis were utilized to confirm the characteristic changes after pretreatment. The results showed that the severe pretreatment condition tended to increase the carbohydrate losses. From FTIR spectra, microwave pretreatment tended to decrease absorbancy of functional group bands. After microwave pretreatment for 12.5 min (770 W), the band around 1736 cm-1 (C=O in xylan) disappeared in the samples. The syringil propane unit was lower than that of guaiacyl lignin under microwave pretreatment. The disruption of the structure of the cell wall increased the accessibility of cellulase to lignocellulose. Except microwaving for 5 min (330 W), the microwave heating caused carbon and oxygen increasing compared to untreated samples. The increase in crystallinity index of pretreated bamboo suggested the selective degradation of amorphous components.

BIOAKTIVITAS ZAT EKSTRAKTIF KULIT Acacia auriculiformis A. Cunn. ex Benth. TERHADAP RAYAP TANAH (Coptotermes curvignathus Holmgren)

This research was undertaken mainly to isolate and identify antitermitic substances that may be prospective as wood natural preservative from the bark of Acacia auriculiformis A. Cunn. ex Benth. The woodmeal of the samples were extracted with acetone. The acetone extract was then fractionated into n-hexane soluble fraction, ethyl ether soluble fraction, ethyl acetate soluble fraction, and insoluble fraction. The antifeedant bioassay test was carried out by treating paper discs with extracts at six level of concentration i.e. 0%, 2%, 4%, 6%, 8%, and 10% (w/w). The bioassay test revealed that ethyl ether soluble fraction exhibited high toxicity to subterranean termite Coptotermes curvignathus Holmgren (concentration of 4% has been indicated very strong activity). Keywords: Bioactivity, extractives, Acacia auriculiformis, termites, Coptotermes curvignathu

ARANG AKTIF SEBAGAI BAHAN PENANGKAP FORMALDEHIDA PADA KAYU LAPIS

ABSTRACTThis paper discusses the activated charcoal from jati (Tectona grandis L.f) sawdust used as catching agent of formaldehyde on plywood glued with urea formaldehyde. The activated charcoal was produced in a stainless steel retort with electrical heater at temperature of 8500C by using NH4HCO3 0.25 % as activating agent with reaction time of 90 minutes. To reduce formaldehyde emission from plywood, activated charcoal were added to urea formaldehyde adhesives at four levels i.e 0, 2, 4, 6 and 8 %.  FTIR, XRD and SEM were used to evaluate the structure of activated charcoal.  The results showed that the yield of activated charcoal was 53.11 %, moisture content 1.43 %, ash content 7.07 %, volatile matter 6.07 %, and fixed carbon 86.85 %. The adsorptive capacity of iodine 1196.6 mg/g, benzene 21.75 %, formaldehyde 48.12 % and methylene blue 319.18 mg/g and surface area 1183.4 m2/g. The quality of activated charcoal especially the adsorptive capacity of iodine has met the commercial standard requirement of the Japanese Standard. The structure of activated charcoal was polar, amorphous and macropore with pore diameter range from 1.3 – 1.6 m, degree of crystalinity 26.0 %, the height (Lc) and wide (La) were 2.47 and  13.42 nm. The number (N) of aromatics layer was 7.0.The free formaldehyde content of urea formaldehyde resin and the emission of formaldehyde from plywood decreased as the concentration of activated charcoal increased, and the bonding strength of plywood met the Indonesian and Japanese Standard requirement.  Keywords: activated charcoal, jati, structure, iodine, formaldehyde, plywoo

ARANG AKTIF SEBAGAI BAHAN PENANGKAP FORMALDEHIDA PADA KAYU LAPIS

ABSTRACTThis paper discusses the activated charcoal from jati (Tectona grandis L.f) sawdust used as catching agent of formaldehyde on plywood glued with urea formaldehyde. The activated charcoal was produced in a stainless steel retort with electrical heater at temperature of 8500C by using NH4HCO3 0.25 % as activating agent with reaction time of 90 minutes. To reduce formaldehyde emission from plywood, activated charcoal were added to urea formaldehyde adhesives at four levels i.e 0, 2, 4, 6 and 8 %.  FTIR, XRD and SEM were used to evaluate the structure of activated charcoal.  The results showed that the yield of activated charcoal was 53.11 %, moisture content 1.43 %, ash content 7.07 %, volatile matter 6.07 %, and fixed carbon 86.85 %. The adsorptive capacity of iodine 1196.6 mg/g, benzene 21.75 %, formaldehyde 48.12 % and methylene blue 319.18 mg/g and surface area 1183.4 m2/g. The quality of activated charcoal especially the adsorptive capacity of iodine has met the commercial standard requirement of the Japanese Standard. The structure of activated charcoal was polar, amorphous and macropore with pore diameter range from 1.3 – 1.6 m, degree of crystalinity 26.0 %, the height (Lc) and wide (La) were 2.47 and  13.42 nm. The number (N) of aromatics layer was 7.0.The free formaldehyde content of urea formaldehyde resin and the emission of formaldehyde from plywood decreased as the concentration of activated charcoal increased, and the bonding strength of plywood met the Indonesian and Japanese Standard requirement.  Keywords: activated charcoal, jati, structure, iodine, formaldehyde, plywoo

HIDROLISIS ENZIMATIS DAN MICROWAVE BAMBU BETUNG (Dendrocalamus asper (Schult.f.)) SETELAH KOMBINASI PERLAKUAN PENDAHULUAN SECARA BIOLOGIS DAN MICROWAVE

Enzymatic and acid microwave-assisted hydrolysis of a newly combined biological and microwavepretreatment was developed to evaluate the reducing sugar yield of betung bamboo fibers. In previous parallelstudy of single (biological or microwave) pretreatment, the improvement of reducing sugar yield of microwaveassistedacid hydrolysis has been reported previously. The cellulase of 10 and 20 FPU/g substrate was appliedin the enzymatic hydrolysis of pretreated biomass using a shaking incubator at 50°C and 150 rpm for 48 hours.In the microwave-assisted acid hydrolysis, 1.0% sulfuric acid concentration was used either with or without theactivated carbon aditionat microwave hydrolysisat 330 watt for 7.5-12.5 minutes. There was an improvement inreducing sugar yield of bamboo pretreated biological-microwave pretreatment after microwave assisted-acidhydrolysis compared to enzymatic hydrolysis. This hydrolysis performance improvement was greater than that ofthe single pretreatment (biological or microwave pretreatment). Bamboo pretreated by biological-microwavepretreatment (5% inoculum loading and irradiated for 5 minutes at 330 W) showed the highest reducing sugaryield after microwave hydrolysis for 12.5 minutes (16.65% per dry biomass or 18.92% per dry substrate). Asmuch as 27.21% of hollocellulose can be converted to reducing sugar or 23.84% of theoritical maximumreducing sugar yield. The benefical effect of activated carbon addition in microwave assisted acid hydrolysiswas the reduction of brown compound even though oligomer adsorption caused the decreasing of reducing sugaryield.Keywords: betung bamboo, brown compound, combination of biological and microwave pretreatment, enzymaticand acid-microwave hydrolysis, reducing sugar yiel

The Influence Of Reactant Ratio (Eupcalyptus Lignin – Sodium Bisulfite) And Initial Ph Towards Characteristcs Of Sodium Lignosulfonate

Eucalyptus lignin was isolated from kraft black liquor through by acidification using H2SO4. Sulfonation of eucalyptus lignin produced sodium lignosulfonate (SLS) which can be used as dispersants, and emulsifier. In this research, sulfonation was carried out towards lignin with mass ratio of eucalyptus lignin-NaHSO3 (b/b) of 1:0.4, 1:0.5, and 1:0.6, and initial pH of 5, 6, 7, 8. Studies on the effect of various ratio of eucalyptus lignin versus NaHSO3 (1 based on w/w) and initial pH of 5,6,and 7 for the sulfonation reaction showed an  increasing yield and improved purity of SLS obtained.  However, no significant result was observed on the application of initial pH  7 and 8 toward increasing of SLS yield and purity.  The highest SLS  yield of 83.8% with  purity of 82.9% was obtained under condition of initial pH at 7 and the mass ratio of eupcayptus lignin over NaHSO3 was 1:0.5.  The resulted SLS was light brown, water soluble, with  pH level between 6.3 and 7.24, and released sulfur-like odor.Key words: lignin, kraft black liquor,  sodium lignosulfonate

Kajian Struktur Arang dari Lignin

Tulisan ini membahas struktur arang dari lignin pada suhu karbonisasi yang berbeda. Proses pembuatan arang lignin dilakukan pada suhu 200, 300, 400, 500, 650, 750 dan 850°C dalam suatu retort yang terbuat dari baja tahan karat yang dilengkapi dengan pemanas listrik Untuk mengetahui Perubahan struktur arang yang terjadi dilakukan analisis dengan menggunakan FTIR, XRD dan SEM. Hasil analisis XRD menunjukkan bahwa jarak antar ruang lapisan aromatik (d) dan lebar lapisan aromatik (La) menurun dengan makin meningkatnya suhu karbonisasi, sedangkan untuk tinggi lapisan aromatik (Lc), derajat kristalinitas (X) dan jumlah lapisan aromatik (N) meningkat dengan makin naiknya suhu karbonisasi. Spektrum FTIR dari arang lignin menunjukkan bahwa antara suhu 300-500°C terjadi Perubahan struktur kimia dari bahan baku secara nyata. Ikatan OH, dan C=C alifatik menurun dengan naiknya suhu, sedangkan struktur eter dan aromatik makin berkembang. Pada suhu 850°C arang yang dihasilkan mempunyai struktur aromatik yang permukaannya mempunyai gugus C-O-C, C=O dan C- H. Analisis SEM menunjukkan bahwa jumlah dan diameter pori arang meningkat dengan makin naiknya suhu karbonisasi. Kualitas arang yang baik diperoleh pada suhu karbonisasi 500°C yang menghasilkan derajat kristalinitas sebesar 33,90 %, tinggi lapisan aromatik 3.21 nm, lebar lapisan aromatik 10,96 nm, jumlah lapisan aromatik 8,67, jarak antar lapisan aromatik d(002) = 0,35 nm dan d(100) = 0,21 nm dengan diameter pori arang antara 12,6 mm. Arang ini mempunyai sifat keteraturan yang tertinggi, permukaannya bersifat polar, kaku, keras dan struktur porinya makropor

The Characteristic Changes of Betung Bamboo (Dendrocalamus Asper) Pretreated by Fungal Pretreatment

The fungal pretreatment effect on chemical structural and morphological changes of Betung Bamboo was evaluated based on its biomass components after being cultivated by white rot fungi, Trametes versicolor. Betung bamboo powder (15 g) was exposed to liquid inoculum of white rot fungi and incubated at 270C for 15, 30 and 45 days. The treated samples were then characterized by FT-IR spectroscopy, X-Ray diffraction and SEM-EDS analyses. Cultivation for 30 days with 5 and 10% loadings retained greater selectivity compared to that of the other treatments. FTIR spectra demonstrated that the fungus affected the decreasing of functional group quantities without changing the functional groups. The decrease in intensity at wave number of 1246 cm-1 (guaiacyl of lignin) was greater than that at wave number of 1328 cm-1 (deformation combination of syringyl and xylan) after fungal treatment. X-ray analysis showed the pretreated samples had a higher crystallinity than the untreated ones which might be due to the cleavage of amorphous fractions of cellulose. The pretreated samples have more fragile than the untreated ones confirmed by SEM. Crystalline allomorph calculated by XRD analysis showed that fungus pretreatment for 30 days has transformed triclinic structure of cellulose to monoclinic structure