Garuda - Garba Rujukan Digital

Phytochemical screening and determination of total phenolic and total flavonoid contents of pear peel extracts Patricia, Vinda Maharani; Saputri, Fauzia Ningrum
Farmasains : Jurnal Farmasi dan Ilmu Kesehatan Vol 4, No 2 (2019): November
Publisher : University of Muhammadiyah Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22219/farmasains.v4i2.10166

The study was carried out to investigate the presence of different phytochemicals as well as to determine the total phenolic and flavonoid contents of green pear/european pear peels and yellow pear/asian pear peels. Phytochemical screening of the pear peels was carried out following standard protocols. Total phenolic content was determined by Folin-Ciocalteu method and total flavonoid contents was determined by Aluminum Chloride Colorimetric method, measured using n-hexane, etil acetate, and methanol. Phenolics, flavonoids, tannins, alkaloids, and saponins are present in green pear and yellow pear peels. The total phenol and flavonoid contents are highest in methanol extracts in which green pear peels have a higher concentration than yellow pear peels. In conclusion, the green and yellow pear peels are rich in phenolic compounds and have great potential as natural antioxidants. Therefore, the results of this research should be considered to provide the possibility for future developments of highly functional antioxidants.

Phytochemical screening and determination of total phenolic and total flavonoid contents of pear peel extracts Vinda Maharani Patricia; Fauzia Ningrum Saputri
Farmasains : Jurnal Farmasi dan Ilmu Kesehatan Vol. 4 No. 2 (2019)
Publisher : Universitas Muhammadiyah Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22219/farmasains.v4i2.10166

The study was carried out to investigate the presence of different phytochemicals as well as to determine the total phenolic and flavonoid contents of green pear/european pear peels and yellow pear/asian pear peels. Phytochemical screening of the pear peels was carried out following standard protocols. Total phenolic content was determined by Folin-Ciocalteu method and total flavonoid contents was determined by Aluminum Chloride Colorimetric method, measured using n-hexane, etil acetate, and methanol. Phenolics, flavonoids, tannins, alkaloids, and saponins are present in green pear and yellow pear peels. The total phenol and flavonoid contents are highest in methanol extracts in which green pear peels have a higher concentration than yellow pear peels. In conclusion, the green and yellow pear peels are rich in phenolic compounds and have great potential as natural antioxidants. Therefore, the results of this research should be considered to provide the possibility for future developments of highly functional antioxidants.

Formulation and Physical Characterization of Onion (Allium ascalonicum L) Bulb Extract in Cream Using Tween 80 and Span 60 as the Emulgator Fauzia Ningrum Syaputri; Vinda Maharani Patricia
Jurnal Sains dan Kesehatan Vol. 2 No. 2 (2019): Jurnal Sains dan Kesehatan
Publisher : Fakultas Farmasi, Universitas Mulawarman, Samarinda, Indonesia

In Indonesia, it is not uncommon to find children who suffer from fever which can occur due to the change of weather from the rainy season during the dry season or vice versa. Communities in rural areas generally use onion (Allium ascalonicum L) to relieve fever in children. Cream preparations are made by varying the concentration of the emulgator to determine the effect of different concentrations of the emulgator on the physical characteristics of the cream preparation. The emulgator used is tween 80 and span 60 with a concentration of Formula 1: 3.5%, Formula 2: 3.75%, formula 3: 4%. Physical evaluations carried out in this study were organoleptic, pH, homogeneity, cream washability, cream type, viscosity, spreadability, adhesion, and freeze-thaw tests. The results of the study it can be concluded that the differences in the concentration of the emulgator can affect the physical characteristics of the cream preparation, namely in the spreading test and the adhesion test shows that F3 (4%) can reduce the spreadability of the cream preparation but can be attached to a long time when compared to F1 (3.5%) and F2 (3.75%). The physically optimal cream preparation formula is F1 and F2 because it meets all the requirements in the evaluation test. Keywords: Cream, onion, emulgator, physical characteristics

Studi Literatur Aktivitas Antibakteri Ekstrak Biji Kelor (Moringa oleifera (Lam.)) terhadap Bakteri Patogen pada Saluran Cerna Nanda Aulia Rahma; Indra Topik Maulana; Vinda Maharani Patricia
Bandung Conference Series: Pharmacy Vol. 2 No. 2 (2022): Bandung Conference Series: Pharmacy
Publisher : UNISBA Press

Abstract. The gastrointestinal tract infection is a disease that often occurs in Indonesia. This disease caused by pathogenic bacteria such as Staphylococcus aureus, Escherichia coli, and Salmonella typhi. Moringa oleifera seed is part of a Moringa oleifera that has potential as an antibacterial. This study aims to determine the potential antibacterial activity of Moringa oleifera seed extract against pathogenic bacteria in the gastrointestinal tract and determine the compounds in Moringa oleifera seed extracts and their mechanism of action as antibacterial. The research method used in this study is a systematic literature review. The results of this study indicate that Moringa oleifera seed extracts has antibacterial activity against pathogenic bacteria in the gastrointestinal tract, which is indicated by the production of MIC values and the identification of compounds that act as antibacterial. The antibacterial activity of Moringa oleifera seed extract against Escherichia coli was the most effective antibacterial activities. Moringa oleifera seed extract contains napin-1A peptide which works by inhibiting bacterial protein synthesis. Abstrak. Penyakit infeksi pada saluran cerna merupakan penyakit yang sering terjadi di Indonesia. Penyakit ini disebabkan oleh bakteri patogen seperti Staphylococcus aureus, Escherichia coli, dan Salmonella typhi. Biji kelor (Moringa oleifera (Lam.)) merupakan salah satu bagian dari tanaman kelor yang memiliki potensi sebagai antibakteri. Penelitian ini bertujuan untuk mengetahui potensi aktivitas antibakteri dari ekstrak biji kelor terhadap bakteri patogen pada saluran cerna dan mengetahui senyawa pada ekstrak biji kelor beserta mekanisme aksinya sebagai antibakteri. Metode penelitian yang dilakukan dalam penelitian ini adalah systematic literature review. Hasil dari penelitian ini menunjukkan bahwa ekstrak biji kelor memiliki aktivitas antibakteri terhadap bakteri patogen pada saluran cerna yang ditandai dengan dihasilkannya nilai KHM serta teridentifikasinya senyawa yang berperan sebagai antibakteri. Aktivitas antibakteri dari ekstrak biji kelor terhadap bakteri Escherichia coli merupakan aktivitas antibakteri yang paling efektif. Pada ekstrak biji kelor terkandung senyawa napin-1A peptida yang bekerja dengan cara menghambat sintesis protein bakteri.

Pengaruh Perbedaan Pelarut Ekstraksi terhadap Aktivitas Antioksidan Ekstrak Kulit Buah Naga yang Diekstraksi dengan Metode Ultrasound-Assisted Extraction (UAE) Jihan Hana Fauziah; Kiki Mulkiya Yuliawati; Vinda Maharani Patricia
Bandung Conference Series: Pharmacy Vol. 2 No. 2 (2022): Bandung Conference Series: Pharmacy
Publisher : UNISBA Press

Abstract. Dragon fruit peel, which has been considered waste thus far, turns out to contain extraordinary benefits, one of which is as a source of natural antioxidants that have the potential to be developed. This study aimed to determine the effect of differences in extraction solvents on the antioxidant activity of dragon fruit peel extracts (Hylocereus Polyrhizus) extracted using the Ultrasound-Assisted Extraction (UAE) method. The extraction process did using aquadest:citric acid and ethanol 96%:citric acid with a pH of 4,5 sonicated at 45 kHz for 60 minutes at 40oC. The viscous extract was tested for antioxidant activity using the DPPH method (1,1-Diphenyl-2-picrylhydrazil. The results of testing the antioxidant activity in aquadest:citric acid and ethanol 96%:citric acid with IC50 values of 133,37 ppm and 167,37 ppm, consecutively, indicated that the antioxidant activity of dragon fruit peel was in the weak-moderate category. Data analysis on antioxidant activity was carried out using the Kruskal Wallis test. The comparison results of the two solvents contained significant differences in the antioxidant activity test. Abstrak. Kulit buah naga yang selama ini hanya dianggap limbah ternyata mengandung manfaat yang luar biasa, salah satunya sebagai sumber antioksidan alami yang sangat berpotensi untuk dikembangkan. Penelitian ini bertujuan untuk mengetahui pengaruh pelarut ekstraksi yang berbeda terhadap aktivitas antioksidan ekstrak kulit buah naga (Hylocereus polyrhizus) yang diekstraksi dengan metode Ultrasound-Assisted Extraction (UAE). Proses ekstraksi dilakukan dengan menggunakan aquadest:asam sitrat dan etanol 96%:asam sitrat dengan pH 4,5 disonikasi pada 45 kHz selama 60 menit pada 40oC. Ekstrak kental dilakukan pengujian aktivitas antioksidan menggunakan metode DPPH (1,1-Difenil-2-pikrilhidrazil). Hasil pengujian aktivitas antioksidan pada pelarut aquadest:asam sitrat dan etanol 96%:asam sitrat dengan nilai IC50 berturut-turut 133,37 ppm dan 167,37 ppm menunjukkan aktivitas antioksidan dari kulit buah naga termasuk kategori sedang dan lemah. Dilakukan analisis data pada aktivitas antioksidan menggunakan uji Kruskal Wallis, dimana hasil perbandingan antara kedua pelarut terdapat perbedaan signifikan pada pengujian aktivitas antioksidan.

Karakterisasi dan Penetapan Kadar Flavonoid Total Ekstrak Kulit Kentang (Solanum tuberosum L.) Tasya Luthfiyyah; Vinda Maharani Patricia
Bandung Conference Series: Pharmacy Vol. 2 No. 2 (2022): Bandung Conference Series: Pharmacy
Publisher : UNISBA Press

Abstract. Potato (Solanum tuberosum L.) is the main staple food for humans and the fourth largest crop grown worldwide after rice, wheat and maize. Potato peel, a waste by-product of potato processing, can be considered a new source of natural antioxidants because it contains a number of antioxidant compounds such as phenolic compounds and flavonoid compounds. Based on this background, the purpose of this study was to determine the characterization of simplicia and potato peel extract and to determine the total flavonoid content of potato peel extract. The characterizations included organoleptic tests, determination of the content of soluble extracts in water and ethanol, determination of water content, drying shrinkage, determination of total ash content and acid insoluble ash content, and determination of specific weight. Extraction was carried out using the maceration method for 3x24 hours with two remacerations using 96% of ethanol. Determination of total flavonoid content was carried out using the AlCl3 method using a UV-Vis spectrophotometer and routine as a comparison. The results showed that potato peel simplicia had a faded brown color, fine powder form, characteristic smell, and tasteless. As for the results of potato peel extract, it is dark brown in color, thick, has a characteristic sweet smell, and has a bitter taste. In the water-soluble extract test the results were 32.642%, ethanol soluble extract content was 23.764%, water content was 4.5%, drying loss was 6.309%, total ash content was 4.998%, acid insoluble ash content was 1.195%, and the specific gravity of the extract was 0.7718. The total flavonoid content in potato peel extract was 15.9689 mg RE/g extract Abstrak. Kentang (Solanum tuberosum L.) merupakan makanan pokok utama bagi manusia dan tanaman terbesar keempat yang ditanam di seluruh dunia setelah padi, gandum, dan jagung. Kulit kentang yang merupakan produk sampingan limbah dari pengolahan kentang, dapat dianggap sebagai sumber baru antioksidan alami karena kulit kentang mengandung sejumlah senyawa antioksidan senyawa golongan fenolik dan flavonoid. Berdasarkan latar belakang tersebut, maka tujuanpenelitian ini yaitu untuk mengetahui karakterisasi simplisia dan ekstrak kulit kentang serta mengetahui kadar flavonoid total dari ekstrak kulit kentang. Karakterisasi yang dilakukan meliputi uji organoleptik, penetapan kadar sari larut dalam air dan etanol, penetapan kadar air, susut pengeringan, penetapan kadar abu, total dan kadar abu tak larut asam, serta penetapan bobot jenis. Ekstraksi dilakukan dengan menggunakan metode maserasi selama 3x24 jam dengan dua kali remaserasi menggunakan pelarut etanol 96%. Penetapan kadar flavonoid total dilakukan dengan metode AlCl3 menggunakan spektrofotometer UV-Vis dan rutin sebagai pembanding. Hasil penelitian menunjukkan simplisia kulit kentang memiliki karakteristik warna cokelat pudar, bentuk serbuk halus, bau khas, dan tidak berasa. Adapun untuk hasil ekstrak kulit kentang berwarna cokelat tua pekat, bentuk kental, bau khas manis, dan rasa pahit. Pada uji kadar sari larut air didapatkan hasil sebesar 32,642%, kadar sari larut etanol sebesar 23,764%, kadar air sebesar 4,5%, susut pengeringan sebesar 6,309%, kadar abu total sebesar 4,998%, kadar abu tak larut asam sebesar 1,195%, dan bobot jenis ekstrak sebesar 0,7718. Adapun kadar flavonoid total dalam ekstrak kulit kentang adalah sebesar 15,9689 mg RE/g ekstrak

Uji Aktivitas Antibakteri Ekstrak Etanol Kulit Melinjo (Gnetum gnemon L.) terhadap Pertumbuhan Bakteri Propionibacterium acnes Rodhiatul Jurdillah; Vinda Maharani Patricia; Kiki Mulkiya Yuliawati
Bandung Conference Series: Pharmacy Vol. 2 No. 2 (2022): Bandung Conference Series: Pharmacy
Publisher : UNISBA Press

Abstract. Acne can occur due to increased production of excess sebum, causing inflammation due to the activity of the bacteria Propionibacterium acnes. Propionibacterium acnes is one of the bacteria that causes acne which has an important role in the pathogenesis of acne. This study was conducted to determine the antibacterial activity of melinjo (Gnetum gnemon L.) fruit peel ethanol extract against the growth of Propionibacterium acnes, find out at what concentration can provide antibacterial activity of melinjo (Gnetum gnemon L.) fruit peel ethanol extract against the growth of Propionibacterium acnes. Extraction was made by maceration method use 96% ethanol. The results of the group identification test showed that the ethanolic extract of melinjo fruit peel was thought to have a class of compounds as antibacterial, namely polyphenols, flavonoids, saponins as well as monoterpenes and sesquiterpenes. Tests were carried out using the agar diffusion method with wells at several concentrations. The concentrations used were 10%, 15%, 20%, 25%, 50% and 80%. The test results showed that the ethanol extract of melinjo fruit peel formed an inhibition zone at a concentration of 80% with an inhibitory diameter of 13,69 mm. Abstrak. Jerawat dapat terjadi akibat peningkatan produksi sebum yang berlebih sehingga menyebabkan terjadinya inflamasi karena aktivitas dari bakteri Propionibacterium acnes. Bakteri Propionibacterium acnes merupakan salah satu bakteri penyebab jerawat yang memiliki peranan penting dalam patogenis jerawat. Penelitian ini bertujuan untuk mengetahui aktivitas antibakteri dari ekstrak etanol kulit buah melinjo (Gnetum gnemon L.) terhadap pertumbuhan bakteri Propionibacterium acnes, mengetahui pada konsentrasi berapa yang dapat memberikan aktivitas antibakteri dari ekstrak etanol kulit buah melinjo (Gnetum gnemon L.) terhadap pertumbuhan bakteri Propionibacterium acnes. Ekstraksi dibuat dengan metode maserasi menggunakan etanol 96%. Hasil uji identifikasi golongan senyawa menunjukkan bahwa ekstrak etanol kulit buah melinjo diduga memiliki golongan senyawa sebagai antibakteri yaitu polifenol, flavonoid, saponin serta monoterpena dan sesquiterpena. Pengujian dilakukan menggunakan metode difusi agar dengan sumuran pada beberapa konsentrasi. Konsentrasi yang digunakan sebesar 10%, 15%, 20%, 25%, 50% dan 80%. Hasil pengujian menunjukan bahwa pada ekstrak etanol kulit buah melinjo terbentuk zona hambat pada konsentrasi 80% dengan diameter hambat 13,69 mm.

Uji Aktivitas Antioksidan Ekstrak Kulit Buah Naga Merah (Selenicereus monacanthus (Lem.) D.R. Hunt) Menggunakan Metode DPPH (2,2-diphenyl-1-picrylhydrazyl) Yuliani Ika Pratiwi; Yani Lukmayani; Vinda Maharani Patricia
Bandung Conference Series: Pharmacy Vol. 2 No. 2 (2022): Bandung Conference Series: Pharmacy
Publisher : UNISBA Press

Abstract. Free radicals are molecules that have an unpaired electron in their outer orbital, so they are highly reactive. Free radicals can come from cigarette smoke, fast food, burning, excessive sun exposure, and air pollution which can cause chronic and degenerative diseases such as damage to cell wall membranes in all tissues. Free radicals can be fought with antioxidants. One of the natural antioxidants is dragon fruit peel (Selenicereus monacanthus) which contains secondary metabolites, one of which is phenol compounds which are thought to be antioxidants. This study aims to determine the percentage of antioxidant activity, namely the IC50 value of the red dragon fruit peel extract using 96% ethanol: citric acid and aquadest: citric acid as a solvent. Measurement of antioxidant activity was carried out using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The results of the antioxidant activity test of red dragon fruit peel extract in 96% ethanol: citric acid and aquades: citric acid solvents were 171.785 ppm and 174.381 ppm, respectively. Abstrak. Radikal bebas merupakan suatu molekul yang mempunyai elektron yang tidak berpasangan pada orbital luarnya sehingga, bersifat sangat reaktif. Radikal bebas dapat berasal dari asap rokok, makanan siap saji, pembakaran, paparan sinar matahari berlebih, serta polusi udara yang dapat timbulnya penyakit kronis dan degeneratif seperti kerusakan pada membran dinding sel hinnga semua jaringan. Radikal bebas dapat ditangkal oleh antioksidan. Salah satu antioksidan alami yaitu kulit buah naga merah (Selenicereus monacanthus) yang mengandung metabolit sekunder salah satunya adalah senyawa fenol yang diduga sebagai antioksidan. Penelitian ini bertujuan untuk mengetahui aktivitas antioksidan yaitu nilai IC50 dari ekstrak kulit buah naga merah menggunakan pelarut etanol 96%:asam sitrat dan aquadest:asam sitrat. Pengukuran aktivitas antioksidan dilakukan menggunakan metode DPPH (2,2-diphenyl-1-picrylhydrazyl). Hasil uji aktivitas antioksidan ekstrak kulit buah naga merah pada pelarut etanol 96%:asam sitrat dan aquadest:asam sitrat berturut-turut yaitu 171,785 ppm dan 174,381 ppm.

Penelusuran Pustaka Potensi Antibakteri Ekstrak Kulit Pepaya (Carica papaya l.) terhadap Bakteri Escherichia coli dan Staphylococcus aureus Adinda Fitri Salsabila; Livia Syafnir; Vinda Maharani Patricia
Bandung Conference Series: Pharmacy Vol. 2 No. 2 (2022): Bandung Conference Series: Pharmacy
Publisher : UNISBA Press

Abstract. Infection is the proliferation of infectious agents in the body caused by microorganisms such as bacteria, viruses, fungi and protozoa. Antibacterial is a substance produced by an organism that has the ability to inhibit or kill microorganisms. One of the plants that have the potential as an antibacterial is papaya. Papaya plants have several benefits such as digestion, antibacterial and treating hypertension. Almost all parts of papaya can be used such as leaves, flowers, fruit, skin and seeds. The papaya skin contains papain enzymes, saponins, alkaloids and glucosides. The research method used is the Systematic Literature Review (SLR). The purpose of this literature review is to collect and analyze the results of research on the potential of papaya peel extract as an antibacterial for Staphylococcus aureus and Escherichia coli bacteria using 96% ethanol extractant with agar diffusion antibacterial testing method. Based on the literature search, the 10% papaya peel extract concentration was more effective in inhibiting Gram-negative bacteria, namely Escherichia coli bacteria. Abstrak. Infeksi merupakan perkembangbiakan agen infeksius di dalam tubuh yang disebabkan mikroorganisme seperti bakteri, virus, jamur dan protozoa. Antibakteri merupakan substansi hasil organisme yang memiliki kemampuan dalam menghambat atau membunuh mikroorganisme. Salah satu tanaman yang berpotensi sebagai antibakteri yaitu pepaya. Tanaman pepaya memiliki beberapa manfaat seperti melancarkan pencernaan, antibakteri maupun mengobati hipertensi. Hampir seluruh bagian pepaya dapat dimanfaatkan seperti daun, bunga, buah, kulit dan bijinya. Adapun pada kulit pepaya mengandung enzim papain, saponin, alkaloid dan glukosid. Metode penelitian yang dilakukan yaitu dengan menggunakan Systematic Literature Review (SLR). Tujuan dari kajian pustaka ini untuk mengumpulkan dan menganalisis hasil penelitian terhadap potensi ekstrak kulit pepaya sebagai antibakteri terhadap bakteri Staphylococcus aureus dan bakteri Escherichia coli menggunakan ekstraktan etanol 96% dengan metode pengujian antibakteri difusi agar. Berdasarkan penelusuran pustaka menunjukan pada konsentrasi ekstrak kulit pepaya 10% lebih efektif dalam menghambat bakteri Gram-negatif yaitu bakteri Escherichia coli.

Kajian Pustaka Potensi Antibakteri Kombinasi Ekstrak Tanaman Sawo Manila (Manilkara zapota (L.) P. Royen) dengan Antibiotik Sintetik terhadap Bakteri Resisten Dwiratnasari; Vinda Maharani Patricia; Indra Topik Maulana
Bandung Conference Series: Pharmacy Vol. 2 No. 2 (2022): Bandung Conference Series: Pharmacy
Publisher : UNISBA Press

Abstract. Infection is a type of disease that mostly affects developing countries, including Indonesia. One of the causes of infectious diseases is bacteria. To reduce the population of bacteria in general use antibiotics. However, irregular use of antibiotics can lead to antibiotic resistance. Manila sapodilla plant (Manilkara zapota (L.) P. Royen) has many health benefits. One of the properties of the sapodilla manila plant is as an antibacterial. This study aims to determine the effect of the combination of synthetic antibiotics with manila sapodilla extract in inhibiting the growth of resistant bacteria. This research was conducted using a literature review study method. Then the data were analyzed related to the potential antibacterial activity of the Brown manila leaves, seeds, and pericarp. The literature study showed that the sapodilla manila plant extract produced a synergistic effect when combined with antibiotics such as tetracycline, erythromycin, ciprofloxacin, chloramphenicol, streptomycin, and kanamycin which was characterized by a decrease in antibiotic MIC when combined. In addition, an antagonistic effect was also produced when combined with the antibiotic ciprofloxacin, which was characterized by an increase in the antibiotic MIC when combined. Abstrak. Infeksi merupakan jenis penyakit yang banyak diderita oleh negara-negara berkembang termasuk Indonesia. Penyakit infeksi dapat disebabkan salah satunya yaitu bakteri. Untuk mengurangi populasi bakteri pada umumnya menggunakan antibiotik. Akan tetapi, jika penggunaan antibiotik secara tidak teratur dapat menyebabkan terjadinya resistensi antibiotik. Tanaman sawo manila (Manilkara zapota (L.) P.Royen) memiliki banyak khasiat untuk kesehatan. Salah satu khasiat dari tanaman sawo manila adalah sebagai antibakteri. Tujuan penelitian ini untuk mengetahui pengaruh kombinasi antibiotika sintetik dengan ekstrak sawo manila dalam menghambat pertumbuhan bakteri yang resisten. Penelitian ini dilakukan dengan metode studi literatur review. Kemudian data tersebut dianalisis terkait dengan potensi aktivitas antibakteri dari bagian daun, biji, dan perikarp sawo manila. Hasil studi literatur menunjukkan bahwa ekstrak tanaman sawo manila diketahui menghasilkan efek sinergis saat dikombinasikan dengan antibiotik seperti tetrasiklin, eritromisin, siprofloksasin, kloramfenikol, streptomisin, dan kanamisin terhadap bakteri Escherichia coli, Enterobacter aerogenes, dan Pseudomonas aeruginosa yang ditandai dengan adanya penurunan KHM antibiotik saat dikombinasikan. Selain itu, dihasilkan juga efek antagonis terhadap bakteri Staphylococcus aureus saat dikombinasikan dengan antibiotik siprofloksasin yang ditandai dengan adanya kenaikan KHM antibiotik saat dikombinasikan.

Title

Found 19 Documents
Search

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Title Search

Found 19 Documents Search

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Title

Found 19 Documents
Search