Potensi Mikroorganisme Indigen Perairan Teluk Lampung sebagai Pendegradasi Masker Sekali Pakai (Disposable Face Mask)

To prevent the transmission of COVID-19, the World Health Organization recommends the implementation of health protocols including using disposable masks. The use of disposable face masks has an impact on the emergence of mask waste in aquatic environments which results in pollution of water sources by microfibers. Degradation by indigenous microorganisms can be one of the solutions for handling waste that is environmentally friendly and cost effective. In this study, bacteria were isolated from the coast of Lampung Bay which was polluted with plastic waste and masks. Bacterial isolates were characterized by morphological and biochemical tests before the selected one being used for degradation. After seven days of incubation, gravimetric analysis showed that the mask pieces increased in weight when compared to the control. However, the degradation process can be shown by the results of Scanning Electron Microscope (SEM) analysis which shows damage in the form of holes on the surface of the mask when compared to the new mask and the control. SEM images also showed the presence of bacterial biomass remnants attached to the surface of the mask. Based on the results of this study, Lampung Bay indigenous microorganism isolate showed potential as a degrader of disposable face masks

Pengawetan Ekstrak Pewarna Alami dari Daun dan Kulit Buah Kakao (Theobroma cacao L.)

Indonesia has abundant natural resources that are very potential and prospective as raw materials for natural dyes, one of which is the leaves and skins of cocoa pods (Theobroma cacao L.). The purpose of this study is to determine the concentration of preservatives that can effectively inhibit the biodegradation reaction of natural dyes in the extract of leaves and skins of cocoa pods. Extracts of natural dyes that have been centrifuged and preservatives was added, then stored in a closed reactor. The preservatives used are benzoic acid and chitosan. Extraction is carried out for 20 days. Every 2 days, extract was analyzed from the reactor to determine the colorant concentration using gravimetric method. Besides benzoic acid, the same experiments was also carried out on another chitosan dissolved in 2% acetic acid solution. The results showed that the addition of benzoic acid and chitosan dissolved in 2% acetic acid solution can inhibit the biodegradation of leaves and skins of cocoa pods extract. Preservative concentrations of 0.50% benzoic acid and 0.25% chitosan are effective preservatives to inhibit the biodegradation reactio

Production of Magnesium Silicate from Rice Husk with Variation of NaOH Concentration and Reaction Time Length Using Sol-gel Method

Rice husk is a by-product of rice production where as much as 9.9 million tons become organic waste. Rice husk ash, which is rich in silica, can be processed into materials that have high selling value. Magnesium silicate is one of the silica-based composite materials with the chemical formula MgSiO3 with an example of its application as a material in the manufacture of magnesium cement. The manufacture of magnesium silicate is done by sol-gel method with NaOH solvent where this method is relatively easy and uses simple equipment. This study was conducted to know the best NaOH concentration and length of reaction time to produce optimal magnesium silicate. The NaOH concentration variables used were 3 M, 5 M, 7 M, and 9 M, while the variable length of reaction time was 90 minutes and 150 minutes. The best NaOH concentration is 7M with 90 minutes of reaction time. This variable gave 49,9% yield of magnesium silicate compared to 3M with 90 minutes reaction time where it gave 17,4% yield. The analytical tests carried out were FITR where this test was carried out to confirm the formation of magnesium silicat

Limbah Partikel Keramik Platinum dan Kaca Lampu Clear Philips sebagai Additive Semen Pengeboran ditinjau Compressive Strength, Shear Bond Strength, dan Thickening Time

Ceramic and glass particle waste is generated in large quantities as a result of their extensive use in various applications. Inappropriate disposal of the waste can lead to environmental degradation and health hazards. This research utilizes ceramic and glass wastes as drilling cement additives in the oil and gas industry. The objective of this research is to study the effect of adding ceramic and glass waste on the properties of drilling cement, including compressive strength, shear bond strength, and thickening time. With composition percentage ratios of 10%, 20%, 30%, 35%, and 40% by weight of cement, the slurry was poured into 1.2x2 inch cubic molds to test compressive strength and into 1.2x2 inch cylindrical molds to test shear bond strength. The findings of this study indicate that the addition of ceramic and glass waste as a drilling cement additive has a positive effect on compressive strength, shear bond strength, and thickening time and is also effective for use as an alternative additive in drilling cement operation

Demineralisasi Batubara Berkadar Abu Tinggi dengan Leaching Menggunakan Alkali

The study was comdustred on the demineralization of Jambi coal with high ash content as an effort to improve quality. The coal selected first crushed to -80 + 115 mesh. Demineralization was carried out using leacjing process with NaOH 20, 25, and 30% (%weight). The best parameter was used in subsequent leaching process to determine the effect of temperature of 50, 70, 90oC. The result showed that the percentage of demineralization increased with increasing demineralization reduction 34

Pengaruh Kosentrasi Pencampuran Tepung Bonggol Pisang Termodifikasi untuk Pembuatan Mie Basah

Banana tuber flour is a type of non-wheat flour which has a high carbohydrate content so it has the potential to be processed into noodles. However, due to the low protein content and immature physicochemical properties, it is necessary to modify it enzymatically and mix it with wheat flour to obtain good quality noodles. This study aims to obtain enzymatically modified banana tuber flour with suitable characteristics for application in the manufacture of wet noodle products, as well as to obtain a formula (comparison of modified banana tuber flour and wheat flour) which can produce wet noodles that meet the SNI quality requirements. The treatment tested was enzymatically modified banana tuber flour substitution 10%, 20%, 30%, 40% and 0% were used as control variables. Wet noodle products were tested for water content and noodle organoleptic (smell, color and texture) according to SNI 2987:2015 wet noodle quality requirements. The results showed that the level of wet noodles met SNI standards, namely below 65%. The organoleptic test results showed that the best quality wet noodles were obtained from a combination of 10% modified banana tuber flour and 90% wheat flour with a concentration ratio of -amylase enzyme of 10%. The aroma test obtained a combination of 10% modified banana tuber flour and 90% wheat flour with a concentration ratio of -amylase enzyme of 40%

Bioconversion of Fruit Wastes into High Economic Value of Lipids using Heterotrophic Microalgae Aurantiochytrium from Mangrove Forests of Bunyu Island, North Kalimantan

Aurantiochytrium microalgae is recognized as heterotrophic microalgae enables to produce high economic value of lipids for the use in health care industries. This research presents the production of biomass containing lipids through the bioconversion of fruit waste using Aurantiochytrium microalgae. Aurantiochytrium microalgae isolate was obtained from isolated mangrove leaves in the mangrove forest of Bunyu Island, North Kalimantan. The production process takes place in three stages, namely standing culture (SC), pre-culture (PC), and main culture. The SC and PC stages took place 48 hours respectively, while the MC took place 120 hours. The source of nutrition at the main cultivation stage (MC) used monosodium glutamate (MSG) as a nitrogen source, while the carbon source was from fruit waste. Amount of 250 grams of fruit waste was mixed and blended, added with 250 ml of water and then sonicated. The mass ratio of nitrogen source and carbon source was 1:3. The maximum of observed microalgal cell diameters for each stage were 14.5 μm (SC), 19.2 μm (PC) and 25.5 μm (MC). Produced biomass in this experiment has the characteristics of a yellow emulsion liquid, pH 6.2, fishy smell and total dissolved solids (TDS) of 4,820 ppm and a wet biomass of 68 g/

Pengaruh Massa Bioadsorben dari Klobot Jagung Terhadap Penurunan Kandungan Asam Lemak Bebas (FFA), Nilai Peroksida (PV) dan Tingkat Warna Dalam Minyak Sawit Mentah (CPO)

Indonesia as an agricultural country, produces many agricultural products. In addition to agricultural products, agricultural waste is also generated throughout the year. This agricultural waste is still underutilized. One of the efforts to utilize agricultural waste is to process agricultural waste into bioadsorbent. This study aims to study the effect of the mass of bioadsorbent from agricultural waste, namely corn husks on reducing levels of free fatty acids (FFA), peroxide value (PV) and color in crude palm oil (CPO). Clean corn husks are then mashed, after which it is reacted with NaOH to remove the lignin content and neutralized with HCl, so that a bioadsorbent is obtained. Crude palm oil is heated to 80 oC, then mixed with 2 to 10 grams of bioadsorbent according to the variables used. The mixture was stirred at 500 rpm for one hour, and the temperature was maintained at 80 oC. After the adsorption process is complete, the mixture is filtered using a vacuum pump and the filtrate is taken. The filtrate obtained was analyzed for free fatty acid content, peroxide value and color. The research resulted in the more mass of bioadsorbent used, the greater the decrease in free fatty acid levels, peroxide value and color. Using 10 g of bioadsorbent can reduce FFA levels by 41.29%, reduce PV values by 54.96% and reduce color absorbance by 29.06%

Sintesis Nanohidroksiapatit Berbahan Cangkang Keong Sawah (Pila ampullacea) dengan Variasi Konsentrasi H3PO4 Menggunakan Metode Ultrasound Assisted Precipitation

Nanohydroxyapatite with the molecular formula Ca10(PO4)6(OH)2 is a calcium phosphate compound that is most widely used in biomedical applications such as bone and dental implants due to its high biocompatibility. The synthesis of nanohydroxyapatite can be carried out using CaCO3 rich materials such rice field snail shell (Pila ampullacea) with a composition of 93.4% CaCO3. The nanohydroxyapatite synthesis method used is Ultrasound Assisted Precipitation. Calcium obtained from the natural material of rice field snail shell (Pila ampullacea) was reacted with H3PO4 precursor at variable 0.3; 0.5; 0.8; 1; 1.3 M until a precipitate of nanohydroxyapatite particles was formed. To determine the effect of H3PO4 concentration, analysis was conducted on the characteristics of the synthesized nanohydroxyapatite. The SEM-EDX analysis revealed a Ca/P ratio of 1.59-1.72 with spherical particle morphology. The FTIR analysis indicated the presence of hydroxyapatite in the sample through the P-O and O-H functional groups

Pengurangan Kadar Chrom dari Limbah Cair Industri Menggunakan Sistem Sub-Surface Flow Constructed Wetland (Ssf-Cw) dengan Tanaman Akar Wangi pada Media Kerikil dan Granul Fly Ash

Sub-Surface Flow Constructed Wetland (SSF-CW) is one of the engineered of sewage treatment systems built and designed involving aquatic plants, soil or other media and related microbes, with more controlled treatment using sub-surface flow types. The purpose of this study was to determine the ability of aquatic plants to reduce of chromium (Cr) in wastewater, to understand the effect of fly media ash and gravel media in the constructed wetland system in reducing chrom  in wastewater. The Constructed Wetland was designed made of plastic with the Sub-Surface Flow Constructed Wetland (SSF-CW) model with 3 zones, zone 1 which is inlet zone and zone 3 which is outlet having dimensions of 37 x 54.5 x 60 cm, while zone 2 which is a reaction zone with dimensions 75 x 52.6 x 43.5 cm. The results showed that overall chrom removal from wastewater in RI, RII, RIII was 85.76, 93.24, and 74.69%, respectively. During the study, there was a growth of the plants, indicated by the presence of new shoots and an increase in the weight of plants. The kinetic model for reducing chromium content in wastewater at the RI, RII and RIII reactors follows the first order equation with a value of k value of 5.3411; 2,4006; and 0.1330