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All Journal Microbiology Indonesia WARTAZOA Indonesian Bulletin of Animal and Veterinary Sciences JURNAL AGROINDUSTRI HALAL Makara Journal of Science Bioma : Jurnal Ilmiah Biologi
Stella Magdalena
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Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Decision Sciences, Operations Research & Management Education Engineering Immunology & microbiology Industrial & Manufacturing Engineering Medicine & Pharmacology Social Sciences Veterinary

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Utilization of Natural Products as Functional Feed Magdalena, Stella; H, Natadiputri G; F, Nailufar; T, Purwadaria
Indonesian Bulletin of Animal and Veterinary Sciences Vol 23, No 1 (2013)
Publisher : Indonesian Animal Sciences Society

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (196.216 KB) | DOI: 10.14334/wartazoa.v23i1.957

Abstract

The use of antibiotics as feed additive improves performance in livestock. However, scientific data related to the use of antibiotics in feed merge spreading of bacterial resistance in animal and human bodies, therefore the usage of antibiotics in animal production is restricted. This condition raise the utilization of natural antibiotic as functional feed such as phytogenics (essential oil, flavonoid, saponin, and tannin), enzyme, probiotic, and prebiotic to improve the livestock’s performance, quality, and health. Functional feeds increase profitability in animal husbandry production and its use is feeds are expected to be functional foods that may have positive effects in human nutrition. Key words: Functional feed, phytogenic, enzyme, probiotic, prebiotic
Isolation and Characterization of New Antibiotics from Indonesian Coastal Marine Bacteria VERONICA VERONICA; BIBIANA W LAY; STELLA MAGDALENA
Microbiology Indonesia Vol. 8 No. 3 (2014): September 2014
Publisher : Indonesian Society for microbiology

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (150.82 KB) | DOI: 10.5454/mi.8.3.1

Abstract

Antibiotics are organic compounds produced by various microorganisms and have the ability to inhibit the growth or kill other microorganisms. However, the irrational application of antibiotics lead to resistance of microorganisms so that they become ineffective. The objectives of this study were to isolate and characterize new antibiotics from Indonesian coastal marine bacteria. In this study, a total of 141 isolates consisting of seven Streptomyces sp. isolates and 134 isolates of other marine bacteria, were obtained from Indonesian coastal regions. Based on antimicrobial activity assay, four Streptomyces sp. and five marine bacteria isolates showed antimicrobial activity towards Bacillus cereus and Staphylococcus aureus with the diameter of inhibition of 3-12 mm. Further, antimicrobial compounds were produced successfully extracted with six organic solvents, such as 1-butanol, dichloromethane, n-hexane, chloroform, and toluene. The best solvent to extract antimicrobial compounds from Streptomyces sp. isolates was 1-butanol, while the best solvent to extract antimicrobial compounds from other marine bacteria isolates could not be specified. Antimicrobial compounds were successfully separated by thin layer chromatography with mobile phase used were 1-butanol, acetic acid, and water at a ratio of 4:1:2 and retention values obtained at 0.50 and 0.63.
Isolation and Identification of Bacteria from Raw Materials Contaminated by Rope-producing Bacteria ANASTASIA ASRI WIDYASARI; STELLA MAGDALENA; BIBIANA WIDIYATI LAY
Microbiology Indonesia Vol. 9 No. 3 (2015): September 2015
Publisher : Indonesian Society for microbiology

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (328.587 KB) | DOI: 10.5454/mi.9.3.3

Abstract

Ropey bread is a bacterial spoilage condition of bread. The spoilage involved in ropey bread is primarily due to Bacillus subtilis. Several studies have shown that rope spoilage can be controlled using antimicrobial agents such as acetic acid, lactic acid, and quaternary ammonium cations (QACs/quats). This research consisted of five main steps: isolation, identification, confirmation, and molecular characterization of bacteria from raw materials contaminated by rope-producing bacteria, and antimicrobial test against rope-producing bacteria. The confirmation test was done in order to determine the rope-producing ability of isolates suspected as Bacillus sp. There were two different treatments in this test. In the first treatment, the inoculums were mixed with bread dough. In the second treatment, each slice of loaf was placed into a petri dish, uniformly soaked with inoculums. The first treatment did not show rope spoilage for all of the loaves, however, 6 of 11 loaves in the second treatment developed rope. The largest inhibition halos for antimicrobial test were produced by quats. This means quats is the strongest antimicrobial agent against rope-producing bacteria. The molecular characterization showed that all of the suspected isolates had 98–99% similarity to Bacillus subtilis.
The Genetic Diversity of Endophytic and Phyllosphere Bacteria from Several Indonesian Herbal Plants Soka, Yogiara Susan; Magdalena, Stella; Rachelia, Devi
Makara Journal of Science Vol. 16, No. 1
Publisher : UI Scholars Hub

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Abstract

Herbal plants have been believed by Indonesians to be an alternative medicine to treat illnesses. The bioactive compounds in the plant can be derived from secondary metabolites or from endophytic and phyllosphere bacteria which coexist within medicinal plants. A total of 18 endophytic bacteria and 32 phyllosphere bacteria were isolated from the herbal plants of Citrus sp., Pluchea indica, Curcuma longa, Nothopanax scuttelarium, Piper crocatum, and Andrographis paniculata. About 72% of endophytic bacteria isolates have proteolytic activity and about 11% have lipolytic activity. On the other hand, about 59% of phyllosphere bacteria isolates have proteolytic activity and about 19% have lipolytic activity. Phylogenetic diversity analysis was conducted by using the amplified ribosomal DNA restriction analysis (ARDRA) method and the sequence of 16S rDNA was digested with endonuclease restriction enzymes: MspI, RsaI, and Sau961. The diversity of endophytic and phyllosphere bacterium from the samples of herbal plants was high. Bacteria isolated from the same herbal plant does not always have a close genetic relationship except for the bacteria isolated from the P. indica plant which showed a close genetic relationship with each other
Pengaruh Konsentrasi Gula terhadap Sifat Fisikokimia dan Sensori Biskuit Labu Kuning (Cucurbita Moschata) Agus, Theresia Felita; Magdalena, Stella; lestari, Diana
JURNAL AGROINDUSTRI HALAL Vol. 9 No. 2 (2023): Jurnal Agroindustri Halal 9(2)
Publisher : Universitas Djuanda

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30997/jah.v9i2.5502

Abstract

Biscuit is a snack based on wheat flour. Excessive use of wheat flour makes an increasing import of wheat from other countries. as a solution is to use yellow pumpkin flour for substitution. Yellow pumpkin (Cucurbita moschata) contains high protein, fiber, and also β-carotene as a source of antioxidants. Yellow pumpkin flours were mixed with wheat flour in 3 ratios. The ratio of pumpkin flour and wheat flour are 2:3, 1:1, and 3:2 and also divided into 2 sugar contents, which are 120 g and 60 g. Water content analysis result was 2,57%, which has met SNI requirements with the maximum at 4%. The most preferred biscuit was 2:3 sample with 60 g sugar. Yellow pumpkin biscuits were acceptable in the organoleptic test. The higher yellow pumpkin flour concentration, the color was darker and the texture was easy to break. Proximate analysis for the best formulation was 57,11% carbohydrate, 6,93% protein, 28,68% for fat, water content 4,78% and ash content 2,50%. The total energy was 514 Calories/100 g value and the energy from fat was 258 Calories/100 g. Biskuit merupakan salah satu makanan ringan berbasis tepung terigu. Tingginya penggunaan tepung terigu meningkatkan impor gandum dari negara lain. Sebagai salah satu solusinya adalah penggunaan tepung labu kuning. Labu kuning (Cucurbita moschata) merupakan tanaman yang tinggi serat dan protein serta beta karoten sebagai antioksidan. Penelitian ini menggunakan 3 ratio tepung labu kuning : tepung terigu sebesar 2:3, 1:1, 3:2 dan dengan dua konsentrasi gula yaitu 120 g dan 60 g. Analisis kadar air menghasilkan nilai dengan rata-rata 2,57% dimana telah memenuhi SNI yaitu maksimum 4%. Hasil organoleptik menyatakan biskuit dengan perbandingan 2:3 dan gula 60 g paling disukai. Tepung labu kuning dalam formulasi biskuit dapat diterima secara organoleptik oleh masyarakat. Hasil analisis warna dan daya patah menunjukkan penggunaan tepung labu kuning tinggi menyebabkan warna gelap dan mudah patah. Analisis proksimat pada formulasi terbaik menunjukkan 57,11% karbohidrat, 6,93 % protein, dan 28,68% lemak. Kandungan kadar air 4,78%, dan kadar abu 2,50%. Energi total adalah 514 Kalori /100g dan energi dari lemak menunjukkan hasil 258 Kalori/100g.
INDUCTION ENDOSPORE FORMATION OF Bacillus subtilis KM16 AS A PROBIOTIC CANDIDATE BY OPTIMIZATION OF THE GROWTH CONDITIONS Magdalena, Stella; Geraldine, Adelaide; Yogiara
BIOMA : Jurnal Ilmiah Biologi Vol. 13 No. 1 (2024): April 2024
Publisher : Prodi Pendidikan Biologi, FPMIPATI, Universitas PGRI Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26877/bioma.v13i1.418

Abstract

Probiotics are living microorganisms which have beneficial effects. One of the benefits is enhancing immunity. Therefore, probiotics are often supplemented into food, medical, and aquaculture products. B. subtilis KM16 as endospore-producing bacteria have been known to increase probiotic resistance to confront the unstable conditions of the digestive tract. Spore formation of Bacillus is supported by the optimal condition of growth medium and incubation periods. The sufficient availability of carbon, nitrogen, and mineral source in the growth medium, and environmental conditions can support the formation of optimal endospores. This research aimed to determine the suitable sugar composition of a medium and optimum incubation time suitable for endospores formation of B. subtilis KM16. Glucose and maltose were utilized as a carbon source in several concentration as a growth medium for B. subtilis KM 16. The incubation time was 48 and 72 hours. The viable number of vegetative cells was not significantly different for the type of sugar and incubation periods. Based on the glucose concentration, 0.2% glucose exhibited the uppermost number of cells, while 1% glucose concentration caused the decrease of vegetative cells. In this study, 0.2% glucose with 48 hours incubation period showed the highest percentage of sporulation frequencies, up to 48%, but it was not significantly different from the other glucose concentration. The medium that contains 0.2% glucose with 48 hours incubation period is the best medium for the utilization of B. subtilis KM16 cells and spores as probiotic candidates.
Co-Authors Agus, Theresia Felita ANASTASIA ASRI WIDYASARI BIBIANA W LAY Bibiana W Lay Devi Rachelia Diana Lestari, Diana Geraldine, Adelaide Nailufar F Natadiputri G H Purwadaria T Rachelia, Devi Soka, Yogiara Susan VERONICA VERONICA Yogiara Yogiara Yogiara