Helmina Br. Sembiring
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View article: Microwave-assisted enzymatic production of cosmetic ester 2-ethylhexyl oleate and myristate
Microwave-assisted enzymatic production of cosmetic ester 2-ethylhexyl oleate and myristate Open
The enzymatic microwave-assisted cosmetic esters production from esterification of fatty acids with 2-ethylhexanol using enzyme lipase as a biocatalyst was developed. The parameters of enzyme weight, molar ratio, reaction time and microwav…
View article: Fatty acid methyl ester (FAME) production from sludge solid waste as K2O/SiO2 catalyst
Fatty acid methyl ester (FAME) production from sludge solid waste as K2O/SiO2 catalyst Open
The demand for primary energy sources such as oil continues to increase in line with population growth and technological advancements. The use of biodiesel as an alternative fuel has been widely considered to replace fossil fuels, which ar…
View article: Isolation and Identification of Flavonoid Compound from the Rambutan Stem Bark (Nephelium lappaceum L.)
Isolation and Identification of Flavonoid Compound from the Rambutan Stem Bark (Nephelium lappaceum L.) Open
Flavonoids derived from the stem barks of Rambutan (Nephelium Lappaceum L.) have been extracted. The extraction of Rambutan stem bark was performed by maceration using a methanol solvent. The concentrated methanol extract was diluted in et…
View article: Antioxidant Activity Assay of Eucalyptus pellita Leaf Extract
Antioxidant Activity Assay of Eucalyptus pellita Leaf Extract Open
In pharmacy, eucalyptus leaves are used for various pharmacological activities because they contain phenolic compounds. This study aims to detect phytochemical compounds and test the antioxidant activity of Eucalyptus pellita leaf extract.…
View article: Analysis of Methamphetamine Using Necrophagous Insects For Forensic Entomotoxicology Applications
Analysis of Methamphetamine Using Necrophagous Insects For Forensic Entomotoxicology Applications Open
The high use of methamphetamine (MA) has resulted in many cases of overdose leading to death, where bodies are generally found after several days which complicates the investigation so that a forensic entomotoxicological analysis using ins…
View article: Training in the Manufacture of Softener Fragrance Aroma Therapy in Tembung Village, District Percut Sei Tuan
Training in the Manufacture of Softener Fragrance Aroma Therapy in Tembung Village, District Percut Sei Tuan Open
Tembung Village, Percut Sei Tuan District, Deli Serdang Regency, North Sumatra Province, is a densely populated area. There are more than 200 laundry businesses. The potential for laundry business actors to produce softener and aromatherap…
View article: Isolation and Identification of Flavonoids from Mundu Plant Leaves (Garcinia Dulcis (Roxb.) Kurz)
Isolation and Identification of Flavonoids from Mundu Plant Leaves (Garcinia Dulcis (Roxb.) Kurz) Open
Isolation and identification of the flavonoid compounds found in the leaves of the mundu plant (Garcinia dulcis (Roxb.) Kurz) have been carried out. The leaves of the mundu plant were extracted by maceration with methanol solvent. The conc…
View article: Isolation and Identification of Phenolic Compounds from Ebony Plant Leaves (Diospyros celebica Bakh.)
Isolation and Identification of Phenolic Compounds from Ebony Plant Leaves (Diospyros celebica Bakh.) Open
Isolation of phenolic compounds from Ebony plant leaves (Diospyros celebica Bakh .) was done by maceration technique with methanol solvent. The concentrated extract of methanol dissolved with distilled water and partition was extracted wit…
View article: Material Design of Bimetallic Catalysts on Nanofibers for Highly Efficient Catalytic Reduction of 4-Nitrophenol
Material Design of Bimetallic Catalysts on Nanofibers for Highly Efficient Catalytic Reduction of 4-Nitrophenol Open
In this study, CuO-TiO2 nanofiber catalysts were fabricated by an electrospinning process, followed by thermal annealing at various temperatures ranging from 300 to 700 °C. The phase transformation from CuO to metallic Cu was carried out t…
View article: Waste Passion Fruit Peel as a Heterogeneous Catalyst for Room-Temperature Biodiesel Production
Waste Passion Fruit Peel as a Heterogeneous Catalyst for Room-Temperature Biodiesel Production Open
A low-cost, green, and highly active catalyst which could transesterify oil under ambient conditions is required to reduce the biodiesel production cost. A novel heterogeneous catalyst derived from the waste agroproduct has been developed …
View article: Isolation of phenolic compounds from Eucalyptus citriodora leaves
Isolation of phenolic compounds from Eucalyptus citriodora leaves Open
A phenolic compound has been isolated from the leaves part of Eucalyptus citriodora through maceration, fractionation, and chromatography analysis. The structural elucidation of the isolated compound was carried out using spectroscopy tech…
View article: Calcium carbonate from chicken eggshells as adsorbents
Calcium carbonate from chicken eggshells as adsorbents Open
Further research is needed to try to utilize calcium carbonate from chicken eggshells as an adsorbent. The use of chicken eggshells as adsorbent is expected to minimize the amount of waste generation and reduce environmental pollution. Thi…
View article: Use of milling equipment goat filth as fertilizer which mixed with dolamits in the village persadanta Scub-District Barusjahe Districts Karo
Use of milling equipment goat filth as fertilizer which mixed with dolamits in the village persadanta Scub-District Barusjahe Districts Karo Open
This community service aims to increase insight into the use of goat manure as fertilizer mixed with dolomite with very minimal expenditure of money using equipment provided by the USU Community Service Team in 2019 which was carried out i…
View article: Fungal contamination spices from Indonesia with emphasis on Aspergillus flavus
Fungal contamination spices from Indonesia with emphasis on Aspergillus flavus Open
Filamentous fungi were isolated from ten spices collected from markets in Indonesia. The aim was to enumerate fungal contamination and to determine the toxigenicity of Aspergillus flavus strains on each of the spices. Viable fungal populat…
View article: Antibacterial Activities of Rough Lemon (Citrus jambhiri Lush) Rind Essential Oil
Antibacterial Activities of Rough Lemon (Citrus jambhiri Lush) Rind Essential Oil Open
The isolation of rough lemon (Citrus jambhiri Lush) rind essential oil has been done by using hydrodistillation method and paper disk diffusion test for antibacterial activity test. 2.3 gram (1.51%) of essential oil was obtained from 450 g…
View article: Facile Method to Synthesize N-Graphene Nano Sheets
Facile Method to Synthesize N-Graphene Nano Sheets Open
Oriental Journal of Chemistry is a peer reviewed quarterly research journal of pure and applied chemistry. It publishes standard research papers in almost all thrust areas of current chemistry of academic and commercial importance. It prov…
View article: Synthesis of CMC from Palm Midrib Cellulose as Stabilizer and Thickening Agent in Food
Synthesis of CMC from Palm Midrib Cellulose as Stabilizer and Thickening Agent in Food Open
Oriental Journal of Chemistry is a peer reviewed quarterly research journal of pure and applied chemistry. It publishes standard research papers in almost all thrust areas of current chemistry of academic and commercial importance. It prov…
View article: Isolation and Characterization of Flavonoids Isolated from Leaves of Benalu Jeruk (Scurrula fusca G. Don) as Antioxidant
Isolation and Characterization of Flavonoids Isolated from Leaves of Benalu Jeruk (Scurrula fusca G. Don) as Antioxidant Open
Two flavonoids were isolated from leaves of Benalu Jeruk (Scurrula fusca G. Don) by extracting the leaves powder with methanol.The methanol extract was partitioned with ethyl acetate.The ethyl acetate extract was then partitioned further w…