19 research outputs found

    Green Synthesis of Gold Nanoparticles using Peronema canescens Leaves Extract and Their Catalytic Performance for Dyes and Nitro Compounds

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    The most interesting and well-known research in the field of gold nanomaterials synthesis is the use of "green chemistry" to prepare gold nanoparticles (AuNPs). In this study, Peronema canescens leaf extract was used as the synthesis medium to successfully produce AuNPs in a way that was cheap, quick, and good for the environment. A UV-visible spectrophotometer, particle size analysis (PSA), and transmission electron microscopy (TEM) were used to find out more about the AuNPs that were prepared. The UV-visible spectrophotometer showed a surface plasmon resonance peak at 532 nm, which proves that AuNPs exist in the solution. TEM and PSA both showed that the AuNPs were mostly spherical and had an average diameter of 14.9 nm, respectively. In the presence of NaBH4, the AuNPs were found to speed up the reduction of rhodamine B (RhB), metanil yellow (MY), and 4-nitrophenol (4-NP). The results show that the AuNPs that were prepared in a new way worked very well and could be used in catalysis

    Easy Handling Preparation of Cubic Sulfur in Aqueous Extract of Sapindus rarak rinds

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    The aqueous extract of Sapindus rarak (S. rarak) was produced by heating its rinds in demineralized water at 80 °C. The main experiment was conducted at room temperature by mixing a solution of sodium thiosulfate with the extract obtained previously. After adding dilute hydrochloric acid (10%), fine granules gradually formed in the solution and precipitated when the reaction was stopped and allowed to stand for 24 h. The analysis results showed the consistency of the X-ray diffraction (XRD) peak of the obtained material with sulfur standards. When looked at the surface using scanning electron microscopy (SEM), sulfur was found to be cube-shaped. The formation of cuboidal elemental sulfur possibly occurs due to the covering of thiosulfate ions and elemental sulfur during and after the reaction. Organic compounds were found covering sulfur through elemental and functional group analyses using energy-dispersive X-ray (EDX) and Fourier-transform infrared (FTIR) spectroscopy, respectivel

    KAJIAN BIMBINGAN TEKNIS PRAKTIKUM KIMIA PADA DUA MADRASAH ALIYAH DI BENGKULU TENGAH

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    Kajian ini dilakukan dalam rangka melakukan evaluasi untuk memperoleh informasi tentang manfaat satu kegiatan pengabdian masyarakat yang terkait dengan pengembangan kapasitas pendidikan. Kajian dilakukan melalui pengamatan langsung yang dijabarkan secara deskriptif didukung oleh kajian analisis secara kuantitatif terhadap proses transfer ilmu dan keterampilan terhadap kelompok sasaran. Kajian secara kuantitatif deskriptif dilakukan dengan menyebarkan angket yang diberikan sebelum dan sesudah pelatihan. Hasil analisis terhadap jawaban angket yang diberikan menunjukkan bahwa kegiatan yang telah dilakukan memiliki dampak yang cukup baik. Hal terlihat dari data bahwa sebelum dan sesudah pelatihan terjadi perubahan pola jawaban terhadap pernyataan yang disediakan. Secara umum dapat disebutkan bahwa terjadi penurunan persentase yang signifikan pada pilihan jawaban sangat kurang setuju (SK) dari 20,65% menjadi 0%, dan jawaban kurang setuju (KS) dari 51,63% menjadi 1,63% (penurunan sebesar 50%). Dukungan analisis ini ditunjukkan dengan adanya pergeseran pola jawaban yaitu jawaban cukup (C) naik sebesar 11,41% dari 20,11% menjadi 31.52%, sementara jawaban setuju (S) terjadi kenaikan persentase jawaban sebesar 32,07% dan sangat setuju sebesar 27,17

    Features of Vespa affinis Nest Based on X-ray Diffraction, Spectroscopic, and Surface Morphological Studies

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    The main focus of this research is to ascertain the X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopic pattern, and surface morphology of a hornet (Vespa affinis) nest. The optical microscopic (OM) analysis demonstrated that the nest presented an irregular formation of partition materials. This was confirmed via scanning electron microscopy (SEM), which revealed the presence of a unique form with a honeycomb-like pattern. Meanwhile, the materials largely consisted of carbon and oxygen elements, as was revealed by the energy dispersive X-ray (EDX) analysis, while the XRD analysis indicated that the nest was composed of amorphous materials of cellulose and lignin. Finally, the (FTIR) spectroscopy analysis revealed the presence of a number of peaks, which indicated that the material also consisted of a mixture of cellulose, hemicellulose, and lignin materials. It is envisaged that these results would widen the possibilities of fundamental scientific research on forest products, particularly the use of the V. affinis nest for further biological and chemical researc

    Potensi Daun Pacar Air (Impatiens balsamina L.) dalam Menghambat Pertumbuhan Jamur Rhizopus oryzae L.

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    Pacar air (Impatiens balsamina L.) plant belongs to the Balsaminaceae family and is used as an indigenous medicine in Asia for fingernail inflammation, fractures, and rheumatism treatments. Moreover, the antipruritic, antianaphylactic, antifungal, antibacterial, and antitumor activities of some compounds, especially phenolics and quinones from this plant have been studied extensively. Therefore, this study aims to determine the antifungal activity of Pacar air leaves (Impatiens balsamina L.) methanol extract against Rhizopus oryzae L. and the IC50 value. The results showed that an increase in the concentrations of I. balsamina L. leaves methanol extract significantly raised the fungal growth. Furthermore, the extract inhibition against R. oryzae L. at various concentrations of 0.5; 0.7; 0.9; 1.1; and 1.3% w/v were 10, 21.9, 58.06, 68.06, and 79.72%, respectively, while the IC50 value was 0.896%. Hence, the presence of naphthoquinones and other secondary metabolites are responsible for its antifungal activity. Based on these results, the antifungal potential of I. balsamina L. leaves against soft-rot fungi is useful in the future

    Reduction of 4-nitrophenol Mediated by Silver Nanoparticles Synthesized using Aqueous Leaf Extract of Peronema canescens

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    In this study, we developed an alternative of 4-nitrophenol reduction mediated by silver nanoparticles (AgNPs) which was synthesized using aqueous extract of the Peronema canescens leaf through an eco-friendly approach. The reducing 4-nitrophenol to 4-aminophenol mediated by AgNPS in the presence of sodium borohydride as a hydrogen source proceeded rapidly at room temperature without any additional treatments. The AgNPS synthesis was simple and was carried out under mild conditions. Ultraviolet–visible spectroscopy was performed to examine the properties of the obtained AgNPs, which displayed an absorption peak at 431 nm. A transmission electron microscopy analysis revealed that the AgNPs were spherical in shape and had an average particle size of 19 nm as determined by particle size analysis. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

    Aktivitas Antibakteri Secara In-Vitro Ekstrak Metanol Excoecaria cochinchinensis Lour dan Kombinasinya dengan Obat Komersial

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    The purpose of this study was to look into the antibacterial activity of methanolic extract of Excoecaria cochinchinensis as well as the effect of its combination with antibiotics on the growth of Klebsiella pneumoniae, Enterobacter aerogenes, and Staphylococcus epidermidis. The antibacterial activity test was carried out using the well diffusion method, and the combined effect of the extract and antibiotics was observed using the paper strip diffusion method. At various concentrations (25, 50, 75, 100, 150, 200, and 250 mg/mL), the extract significantly inhibited the growth of K. pneumoniae, E. aerogenes, and S. epidermidis. The inhibitory zone's diameter increased proportionally with the extract concentration. The growth of K. pneumoniae and S. epidermidis was then classified as extremely sensitive (+++) to the addition of the extract at 200 and 250 mg/mL concentrations, meanwhile, E. aerogenes’s with 250 mg/mL of the extract. Secondary metabolites such as oleanolic acid, arjunolic acid, scopoletin, kaempferol, quercetin, diterpenoid compounds, tannins, and other phenolics have been reported from E. cochinchinensis leaves and are thought to be responsible for its antimicrobial activity. The effect of the extract’s combination with antibiotics was insignificant compared to their individual activity, thereby classifying them as indifferent.Tujuan dari penelitian ini adalah untuk menyelidiki aktivitas antibakteri dari ekstrak metanol Excoecaria cochinchinensis serta pengaruh kombinasinya dengan antibiotik terhadap pertumbuhan Klebsiella pneumoniae, Enterobacter aerogenes, dan Staphylococcus epidermidis. Uji aktivitas antibakteri dilakukan dengan metode difusi sumuran, dan efek gabungan dari ekstrak dan antibiotik diamati dengan menggunakan metode difusi kertas. Pada berbagai konsentrasi (25, 50, 75, 100, 150, 200, dan 250 mg/mL), ekstrak secara signifikan menghambat pertumbuhan K. pneumoniae, E. aerogenes, dan S. epidermidis. Selain itu, peningkatan diameter zona hambat berbanding lurus dengan peningkatan konsentrasi ekstrak. Pertumbuhan K. pneumoniae dan S. epidermidis kemudian diklasifikasikan sebagai sangat sangat sensitif (+++) terhadap penambahan ekstrak pada konsentrasi 200 dan 250 mg/mL. Sementara itu, pertumbuhan E. aerogenes diklasifikasikan sebagai sangat sangat sensitif (+++) ketika diberikan 250 mg/mL ekstrak. Metabolit sekunder seperti asam oleanolik, asam arjunolik, skopoletin, kaempferol, kuersetin, senyawa diterpenoid, tanin, dan fenolat lainnya telah dilaporkan dari daun E. cochinchinensis dan diduga bertanggung jawab atas aktivitas antimikrobanya. Efek kombinasi ekstrak dengan antibiotik tidak terjadi peningkatan signifikan jika dibandingkan dengan aktivitas secara tunggal, sehingga diklasifikasikan sebagai efek indifferent

    Preliminary Synthesis of Calcium Silicates using Oil Palm Leaves and Eggshells.

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    A new synthetic procedure is described for the synthesis of calcium silicate derivatives, using natural resources such as eggshell (ES) for calcium and oil palm leaves (OPL) for silica, which do not require prepurification. The reaction is performed by directly converting two weight ratio of the precursors, ES:3OPL and ES:6OPL, to dried-powder form by heat treatment at 900 °C for two hours. The results demonstrate that the concentration of the precursors has an effect on the morphology and crystallinity of the calcium silicate derivatives, mainly Ca2SiO4 and CaSiO3. X-ray diffraction results reveal that the reaction product obtained using a 1:3 ratio is quite pure, and mainly consisted of calcium silicate in the form of Ca2SiO4. The CaSiO3 was also identified in ES:6OPL, together with a small amount of excess non-reacted crystalline silica. Furthermore, a scanning electron microscopy analysis shows that both reaction products have a coarse surface. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

    Wisata Edukasi Tanaman Obat Tradisional di Pekarangan Wisata Alam Desa Rindu Hati

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    Desa Rindu Hati terletak di Kecamatan Taba Penanjung, kabupaten Bengkulu Tengah (Benteng), Provinsi Bengkulu, terus menggali potensi wisata alam yang ada di sekitar desa. Pekarangan rumah warga dapat dijadikan objek wisata edukasi bagi pengunjung wisata desa Rindu Hati. Tanaman obat tradisional dapat menjadi pilihan yang tepat untuk ditanam di pekarangan rumah. Tanaman obat dapat membantu kebutuhan ekonomi masyarakat, terutama di desa Rindu Hati. Tidak hanya untuk tanaman obat, tapi juga untuk tanaman hias, bunga atau buah-buahan. Tanaman ini nantinya dapat diolah menjadi jamu. Mulai jamu dalam bentuk cairan dan langsung minum atau dikemas dalam bentuk bubuk. Inilah yang dimaksud mempunyai manfaat ganda, karena hasilnya dapat memberikan banyak manfaat. Tanaman obat tradisional yang terdapat di pekarangan rumah dapat disusun sedemikian rupa dan diberi label identitas untuk memudahkan pengunjung mengetahui nama, jenis, serta khasiat tanaman obat tradisional tersebut. Informasi yang tersampaikan melalui label identitas pada tanaman obat tradisional dapat membantu pengunjung mengetahui jenis dan khasiat dari tanaman obat tradisional. Kegiatan pengabdian masyarakat ini dilaksanakan terhadap warga sekitar wisata alam desa Rindu Hati Bengkulu Tengah dengan menggunakan metode penyuluhan serta pelatihan menanam tanaman obat tradisional. Tujuannya yaitu untuk menambah nilai desa wisata dan meningkatkan pengetahuan masyarakat terhadap obat tradisional. Hasil dari kegiatan ini dapat meningkatkan kesadaran keluarga di Desa Rindu Hati untuk memanfaatkan pekarangan rumah dengan melakukan penanaman tanaman obat tradisional yang bernilai wisata edukasi

    EKSTRAK BUNGA TAPAK KUDA (Ipomoea pescaprae L. Sweet) SEBAGAI MEDIUM SINTESIS NANOPARTIKEL EMAS

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    Pada penelitian ini, nanopartikel emas disiapkan melalui pendekatan green synthesis menggunakan ekstrak air bunga tapak kuda (Ipomoea pescaprae L. Sweet). Nanopartikel emas yang dihasilkan dianalisis menggunakan spektrofotometer UV-Vis, Mikroskop Leica, Particle Size Analyzer (PSA), Spektrofotometer Fourier Transform Infra-Red (FTIR) dan X-ray Difractometer (XRD). Hasil pengukuran  PSA menunjukkan ukuran partikel terbaik, diperoleh dengan menggunakan perbandingan volume 1 mL  larutan HAuCl4 dengan 9 mL ekstrak yang menghasilkan partikel dengan ukuran rata-rata 16,3 nm. Hasil penampakan dengan mikroskop cahaya, memperlihatkan partikel berbentuk bulat. Pergeseran bilangan gelombang pada spektrum infra-merah menunjukkan adanya interaksi antara metabolit sekunder dari ekstrak dengan material emas. Analisis XRD menunjukkan bahwa nanopartikel emas telah dapat dihasilkan dari kondisi reaksi ini
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