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All Journal Jurnal Dikdas Jurnal Kreatif Tadulako Online Kreatif agriTECH Unnes Science Education Journal Jurnal Penelitian Pendidikan IPA (JPPIPA) Jurnal Akademika Kimia Chimica et Natura Acta Indonesian Journal of Chemistry JANGKA Husada Mahakam: Jurnal Kesehatan Abdi Dosen : Jurnal Pengabdian Pada Masyarakat Jurnal Pendidikan Guru (JPG) Panrannuangku Jurnal Pengabdian Masyarakat Journal for Lesson and Learning Studies Jurnal Kajian Pariwisata Media Eksakta Jurnal Akademika Kimia Mahakam Nursing Journal (MNJ) Jurnal Cendekia Ihya Mitra Sains Jurnal Akademika Kimia
Siti Nuryanti
Department Of Chemistry, Faculty Of Teacher Training And Education, Tadulako University, Jln. Soekarno-Hatta Km 8, Palu
Religion Agriculture, Biological Sciences & Forestry Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Decision Sciences, Operations Research & Management Education Engineering Environmental Science Health Professions Languange, Linguistic, Communication & Media Library & Information Science Materials Science & Nanotechnology Mathematics Medicine & Pharmacology Nursing Physics Public Health Social Sciences Other

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Antioxidant Activity Test of Red Spinach’s Extract (Blitum rubrum) in Ethanol Solvent and Water Solvent with DPPH Nur A. O. Buhang; Siti Nuryanti; Daud K. Walanda
Jurnal Akademika Kimia Vol. 8 No. 3 (2019)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2019.v8.i3.pp153-159

Abstract

The study of red spinach antioxidants (Blitum rubrum) in two types of solvents i.e ethanol and water has been performed. The purpose of this study was to determine the antioxidant activity of red spinach extract from Tinombo Selatan district, Central Sulawesi. Red spinach was macerated in ethanol and water to obtain variations of extract concentrations of 20, 40, 60, and 80 mg/L. Free radicals used were DPPH reagents while vitamin C was used as a positive control. The measurement of absorbance of red spinach’s extract was conducted by spectrophotometric. The results showed that IC50 extract of red spinach in ethanol and water were 51.404 mg/L and 52.227 mg/L, while the value of IC50 vitamin C in ethanol and water solvent was 43.241 mg/L and 140.507 mg/L. Based on the IC50 red spinach’s extract in ethanol and water have strong antioxidant activity.
Analysis of Vitamin C in Kecombrang (Etlingera elatior) Lis K. Djaledje; Mery Napitupulu; Siti Nuryanti
Jurnal Akademika Kimia Vol. 8 No. 4 (2019)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2019.v8.i4.pp214-217

Abstract

Flower kecombrang contains nutrient that are beneficial to the community's nutritional improvement one of vitamin C is needed by the body and as a source of antioxidants. This study aims to determine the levels of vitamin C in flower buds and blooms. Analysis of vitamin C levels in the sample was performed by titration of the iodimetric method. The results of analysis, obtained levels of vitamin C in buds kecombrang flowers were 26.40 mg/100 g and the bloom was 44.26 mg/100 g. The data above showed that vitamin C levels in flower kecombrang increased based on the level of maturity.
Antioxidant Activity Test of Ethanol and Water Extracts of Celery (Apium graveolens L.) Nurmiati Nurmiati; Siti Nuryanti; Tahril Tahril
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2020.v9.i2.pp93-101

Abstract

This study aimed to determine the antioxidant activity of ethanol and water extracts of celery (Apium graveolens L.). Antioxidant activity test in this study used DPPH (2,2-diphenyl-1-picrylhydrazine) as a source of free radicals and vitamin C as a positive control. The antioxidant activity of celery extracts was analyzed using a UV-VIS spectrophotometer. Celery powder was extracted by firstly the maceration method using different solvents (ethanol and water) and secondly with the decoction method using water solvents. Celery extract was tested for antioxidant activity with various concentrations of 20, 40, 60, and 80 ppm. The results obtained that water extract (maceration) had a very strong antioxidant power with 23.713 ppm of IC50 values, for ethanol extract (maceration) had a strong antioxidant power with 59.492 ppm of IC50 value, water extract (dekok) had also a very strong antioxidant with 77.446 ppm of IC50 value, and vitamin C had a very strong antioxidant power with 15.631 ppm of an IC50 value. Based on the IC50 value obtained, the water extract by the maceration method was very good to be used as a source of natural antioxidants, because it had a very strong antioxidant activity value which was equivalent to vitamin C.
Emulsion Stability Tes and Effect of HNO3 Concentration in the Internal Phase on Cadmium Ion Extraction using Liquid Membrane Emulsion Technique Sahida Sahida; Baharuddin Hamzah; Siti Nuryanti
Jurnal Akademika Kimia Vol. 9 No. 1 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2020.v9.i1.pp34-39

Abstract

Study on the emulsion stability and cadmium ion extraction tests was performed using the liquid membrane emulsion technique. This study aimed to determine the emulsion stability between the membrane phase and the internal phase with the variation of the ratio (2:1, 1:1, 2:3, and 1:2), and to determine the maximum conditions of cadmium ion extraction in a solution including the various concentration of HNO3 solution 1, 1.5, 2, and 2.5 M. This study is a laboratory experimental method using benzoyl acetone compound as cation carrier, kerosene as membrane phase, HNO3 solution as the internal phase, span-20 and span-80 as surfactants, and cadmium solution as the sample solution. Cadmium ion concentration in the external phase was determined by UV-VIS spectrophotometer. The result showed that the emulsion stability test which produced the most stable emulsion was in the ratio of the membrane phase and the internal phase 1:1. In addition, the concentration of the HN03 solution resulted in a maximum extraction percentage of 1.5 M with an extraction percentage was 95.28%.
Analysis of Calsium (Ca) and Potassium (K) Levels in Candlenut Shells (Aleurites moluccana Willd) Megawati T. H. Romu; Siti Nuryanti; Siti Aminah
Jurnal Akademika Kimia Vol. 9 No. 1 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2020.v9.i1.pp58-62

Abstract

Candlenut shell (Aleurites moluccana Willd) is a waste produced from processing candlenut plants with a fairly hard texture. The use of candlenut shells as fertilizer, especially in Central Sulawesi, has not been done so much. The aim of this study was to determine the levels of calcium (Ca) and potassium (K) in candlenut shells. Calcium and potassium levels were determined using an atomic absorption spectrophotometer (AAS). The results show that the average calcium level in the candlenut shell is 0.315 ± 0.09%, while the average potassium level is 0.090 ± 0.01%. The results of Ca and K in candlenut shell are expected to be used as raw material for fertilizer production.
Analysis of Flavonoid Levels in Tin (Ficus carica Linn) Fruit Rahmasita Rahmasita; Siti Nuryanti; Supriadi Supriadi
Jurnal Akademika Kimia Vol. 10 No. 1 (2021)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2021.v10.i1.pp32-35

Abstract

Tin fruit is an essential source of bioactive components such as phenol, benzaldehyde, and flavonoids due to the antioxidant properties. Analysis of flavonoid levels on Tin (Ficus carica Linn) fruit was carried out using Uv-Vis spectrophotometry. This study aimed to determine the total flavonoid levels found in Tin (Ficus carica Linn) fruit with a variety of samples of raw, half-ripe, and riped. Extraction of chemical content in Tin (Ficus carica Linn) was carried out by maceration method with ethanol 70%. Total flavonoid levels of the extracts sample were determined through absorption measurements at a wavelength of 520 nm and 700 nm. The results showed that total flavonoid levels in raw, half-ripe, and ripe fruits are 5.778 × 103, 3.056 × 103, and 3.707 × 103 mg/L, respectively, or equivalent to 17334 × 103, 9.168 × 103, and 11.121 × 103 mg/100g, respectively.
Co-pigmentation of Anthocyanin Jamblang Fruit (Syzygium cumini) with Acetic Acid and Alum Chintia N. Barani; Siti Nuryanti; Paulus H. Abram
Jurnal Akademika Kimia Vol. 10 No. 4 (2021)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2021.v10.i4.pp237-246

Abstract

This study aimed to determine the effect of temperature on the stability of anthocyanin jamblang after co-pigmentation with acetic acid and alum. The extraction of Jamblang fruit used the maceration method with n-hexane, ethyl acetate, and ethanol-HCl 0.5% solvents. The total anthocyanin obtained was 70.64 mg/L. Anthocyanin of jamblang fruit was co-pigmented with acetic acid and alum in a concentration of 2.5%; 5%; 7.5%; and 10%, then be heated at various temperatures and heating times. At a temperature of 80 ℃ for 150 minutes, every 30 minutes, absorbance was measured. At a temperature of 60 ℃, the heating was carried out for 225 minutes, and every 45 minutes, absorbance was measured. At a temperature of 40 ℃, the heating was carried out for 300 minutes, and every 60 minutes, absorbance was measured. Absorbance measurements were taken using a UV-VIS spectrophotometer. The results showed that co-pigmentation of anthocyanin occurred proved by shifting λ max from 470 nm (unco-pigmented extract) to 500 nm (co-pigmented extract acetic acid) and 540 nm (co-pigmented extract alum). Acetic acid and alum co-pigments maintained the stability of anthocyanin jamblang at a heating temperature of 60 ℃. It can be seen from decreased absorbance, which is not so significant compared to the decrease at temperatures of 40 and 80 ℃, accompanied by anthocyanin's fading color, which is co-pigmented with acetic acid and alum during the heating process.
Study of Conceptual Change in Chemistry for Class XI Science High School Students Hartarti Uminah; Ijirana Ijirana; Siti Nuryanti
Jurnal Akademika Kimia Vol. 11 No. 2 (2022)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2022.v11.i2.pp77-82

Abstract

Varied initial concepts can be an obstacle or support in understanding a new concept. The study of changes in students' chemical concepts was carried out on thermochemical material. This study aimed to examine changes in students' thermochemical concepts in each subject of high, medium, and low ability. Qualitative descriptive research with mixed methods was conducted on SMAN 1 Bumi Raya Morowali, Central Sulawesi students. The study began by giving an initial test to all students of class XI IPA 1 and 2, as many as 60 students, to obtain initial concept data and the basis for grouping subjects on each ability criterion (high, medium, and low). Every two people from each ability group in semi-structured interviews. Thermochemical material is re-taught using a metacognitive skill learning model and given a final test and interview to get concept data after learning to assess conceptual changes. Five concepts become variables in this study: the heat of reaction, enthalpy of reaction in a calorimeter, Hess's law, energy diagrams, and bond energies. The results showed that concept changes occurred in all high, medium, and low ability subjects. Changes in students' conceptions occurred in the concepts of the heat of reaction, reaction enthalpy, calorimeter, Hess's law, energy diagrams, and bond energy. The most significant conceptual change occurred in the subject of medium ability and low ability, namely the concept of bond energy.
Service Excellence dan Servicescape: Faktor Dominan Dalam Menciptakan Kepuasan Tamu Hotel Amran, Ali; Restiani Widjaja, Yani; Nuryanti, Siti
Jurnal Kajian Pariwisata Vol 1 No 1 (2019): Jurnal Kajian Pariwisata
Publisher : LPPM STP ARS Internasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.51977/jiip.v1i1.135

Abstract

ABSTRAK Service excellence dan servicescape merupakan dua hal penting yang dapat mempengaruhi kepuasan tamu hotel. Tujuan penelitian ini adalah untuk mengetahui pengaruh service excellence dan servicescape terhadap customer satisfaction tamu hotel. Metode yang digunakan dalam penelitian ini adalah metode survey dengan mengambil objek penelitian 96 tamu yang menginap di hotel Villa Lemon Lembang Jawa Barat. Penentuan responden diambil menggunakan metode non probability sampling dengan teknik Accidental sampling. Jenis penelitian ini yaitu penelitian deskriptif verifikatif menggunakan analisis regresi berganda. Penelitian ini menunjukkan hasil bahwa tingkat service excellence sangat tinggi, sedangkan tingkat servicescape dan customer satisfaction tinggi. Pengujian hipotesis menunjukkan bahwa service excellence berpengaruh signifikan terhadap customer satisfaction secara parsial dan servicescape berpengaruh signifikan terhadap customer satisfaction secara parsial. Sedangkan secara simultan service excellence dan servicescape berpengaruh terhadap customer satisfaction. Antara variabel service excellence dan servicescape, variabel yang paling dominan mempengaruhi customer satisfaction yaitu service excellence. Manfaat penelitian ini bagi pelaku wisata hotel yaitu dengan menyadari bahwa service excellence dan servicescape sangat penting dalam meningkatkan kepuasan tamu hotel. Kata kunci: service excellence, servicescape dan customer satisfaction
Generic Science Skills Profile of High School Students in Working on Chemistry Questions Based on Gender Mustapa, Kasmudin; Nuryanti, Siti; Al Gifary, Muhammad
Journal for Lesson and Learning Studies Vol. 6 No. 3 (2023): October
Publisher : Universitas Pendidikan Ganesha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jlls.v6i3.60966

Abstract

The exploration of generic science skills in solving chemistry problems can be influenced by various factors, one of which is gender bias in the learning process. This research aims to measure students' generic skills in solving chemistry problems based on gender. This study is quantitative descriptive research with a pre-experimental method using a One-Shot Case Study design. The sample consists of 20 eleventh-grade students, with 10 male students and 10 female students, selected based on gender and the taught material. Data collection techniques include measurement techniques, observation techniques, and interview techniques. The data analysis technique used is quantitative descriptive analysis. The results of the research show difference in the scores of generic science skills between female and male students. Female students have higher scores in direct observation indicators (80 vs. 79) and logical inference (83 vs. 79). However, there is no significant difference in the cause-and-effect law indicator (74 vs. 74). Meanwhile, male students have a slight advantage in the abstraction indicator (67 vs. 66) and concept building (76 vs. 74). Of the five indicators examined in the form of tests, the abstraction indicator obtains the lowest score, while the highest score is in the logical inference indicator. From these results, there is no significant difference in the generic science skills of male and female students.
Co-Authors A. Ma’ruf Afadil Agustin Tiwow Al Gifary, Muhammad Ali Amran Amran Rede Anang Wahid M.Diah Arun Haryanto Arwansyah Asmaul Husna B, Supriadi Baharuddin Hamzah Barau, Fitri Chairil Anwar Chintia N. Barani Cynthia L. Radiman Daini, Dinda Ulan Daud Karel Walanda Dewi Satria Ahmar Dhamayanti, Noviasri Diniyanti, Diniyanti Edi Sukamto Ergina, Ergina Frantauansyah, Frantauansyah Hartarti Uminah I Made Tangkas Ijirana Indarini Dwi Pursitasari Indarini Dwi Puspitasari Irwan Irwan Jamaludin M Sakung Jeane Maria Mustika Tonahi Jusman Lapatta Karmila Karmila Kasmudin Mustapa Laksono Trisnantoro Lamalat, Tri Sulistiyawati Latupeirisa, Veronica Purnama Sari Lilik Suparwati Lis K. Djaledje Ma’ruf, Ahmad Magfirah, Magfirah Male, Kasmir Sy. Marungkil Pasaribu Megawati T. H. Romu Mery Napitupulu Minarni R.J Minarni Rama Jura Mitha Widya Ningrum Moh. Azhar Afandy Muhamad A. Martoprawiro Muhammad Agus Muljanto Muhammad Silmi Hi Abubakar Nesia Andriana Nirwan Syafrin Nur A. O. Buhang Nur, Kurniati Nurbaeti Nurbaeti Nurdin Rahman Nurfadila, Safna Nurhasan, Abdul Kodir Nurmiati Nurmiati Nursucianti, Nursucianti Paulus H. Abram Pratiwi, Tia Putri Radiansah, Roy Rahmasita Rahmasita Rahmawati, Rahmawati Rasmun, Rasmun Ratman Ratman Ratman Ratman Robiansyah, Yal S, Afadil Sabirin Matsjeh Sahida Sahida Saldi, Heri Salsabila, Unik Hanifah Setianingsih, Rahmadiana Siti Aminah Siti Nurbaya Sitti Rahmawati Somang, Olivia Inrawati I. Sri Mulyani Sabang SRI RAHAYU Sri Wahyuni Sriyulaningsi, Sriyulaningsi Sriyundiyati, Ni Putu Sudarmo, I Gede Suhardi Suhardi Suherman Suherman Suherman Suherman Sulhajir, Wahyuni Supriadi Supriadi Suwiyarsa, I Nyoman Tahril Tri Joko Raharjo U.B., Sitti Nadira Ubaidah, Nurcholis Al Winarti Winarti Yani Restiani Widjaja, Yani Restiani Yuli Nurmayanti Yuma Ardian Allu Yusuf Kendek Yusuf Kendek Yusuf Kendek