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All Journal Journal of Food and Pharmaceutical Science Vegetalika Journal of Tropical Life Science : International Journal of Theoretical, Experimental, and Applied Life Sciences Jurnal Ilmu Dasar AL KAUNIYAH AGRICOLA Indonesian Journal of Biotechnology Bioeksperimen: Jurnal Penelitian Biologi Journal of Tropical Biodiversity and Biotechnology Omni-Akuatika Jurnal Biologi Tropis Biosaintifika: Journal of Biology & Biology Education Journal of Multidisciplinary Applied Natural Science Proceeding Biology Education Conference Berkala Penelitian Hayati Asia Pacific Journal of Sustainable Agriculture, Food and Energy (APJSAFE) Journal of Food and Pharmaceutical Sciences

Yekti Asih Purwestri

Faculty Of Biology, Universitas Gadjah Mada

Author-ID : 422725

Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Control & Systems Engineering Education Energy Environmental Science Immunology & microbiology Materials Science & Nanotechnology Mathematics Medicine & Pharmacology Neuroscience Physics Public Health Veterinary

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Articles

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Effects of Light Quality on Vegetative Growth and Flower Initiation in Phalaenopsis Kumala Dewi; Yekti Asih Purwestri; Yohana Theresia Maria Astuti; Lila Natasaputra; P. Parmi
Indonesian Journal of Biotechnology Vol 19, No 1 (2014)
Publisher : Universitas Gadjah Mada

The effects of LEDs (Light-Emitting Diodes) emitting different colours namely red, blue, red andblue, and white lights on vegetative growth and fl ower initiation of Phalaenopsis have been evaluated.Phalaenopsis“otohine/taisuco fi re bird” seedlings in vitro were subjected to different light qualities for either2 or 4 weeks, and then each seedling was planted in a plastic pot containing sphagnum and grown in thegrowth chamber under similar light quality for 3 months. For fl ower induction, mature Phalaenopsis plantshaving 4 – 6 leaves were grown for 3 months in the growth chamber under different light qualities. The leafspan, chlorophyll, gibberellin and cytokinin content were determined. In addition, the expressions of FT-likegene in the leaf, axillary bud, fl ower bud and stalk were examined.Vegetative growth was enhanced under blue, red-blue or white LEDs compared to that of the control.Gibberellin and cytokinin content increased in the seedlings subjected to white LEDs. Based on the averageof leaf span increment it was suggested that the growth of Phalaenopsis seedlings can be promoted by givingeither blue, red-blue or white LEDs. From the second experiment, it was found that fl ower induction inPhalaenopsis can be obtained in plants that had just fi nished fl owering without the application of LEDs. Theexpression of FT-like gene in the leaf as well as fl ower bud and stalk suggests that this gene is involved infl ower regulation of Phalaenopsis.

Identification of BSA B1 Bacteria and Its Potency of Purified Cellulase to Hydrolyze Chlorella zofingiensis Rifqi Zahroh Janatunaim; Radhiyah Mardhiyah Hamid; Ghea Putri Christy; Yekti Asih Purwestri; Woro Anindito Sri Tunjung
Indonesian Journal of Biotechnology Vol 20, No 1 (2015)
Publisher : Universitas Gadjah Mada

Cellulase has been widely used as biocatalyst in industries. Production of cellulase from microorganismshas many advantages such as short production time and less expense. Our previous study indicated that oneof cellulolytic bacteria from digestive tract of milkfish (Chanos chanos), namely BSA B1, showed the highestcellulase activity. The objective of this study was to determine the phylogenetic of BSA B1 strain using 16SrRNA gene sequence. Furthermore, this study also determine the specific activity of purified cellulase from BSAB1 strain and its potency to hydrolyze Chlorella zofingiensis cellulose. Cellulase was purified using ammoniumsulphate precipitation, dialysis, and ion exchange chromatography. The purified cellulase was used to hydrolyzecellulose of C. zofingiensis. The result demonstrated that BSA B1 strain was closely related with Bacillus aeriusand Bacillus licheniformis. The specific activity of the crude enzyme was 1.543 U mL-1; after dialysis was 4.384 UmL-1; and after chromatography was 7.543 U mL-1. Purified cellulase exhibited activity in hydrolyzed both CMCand C. zofingiensis. Compared to commercial cellulase, purified cellulase had lower activity in hydrolyzed CMCbut higher activity in hydrolyzed C. zofingiensis. Ethanol dehydration could potentially increase the reducingsugar yield in cellulose hydrolysis when used appropriately. Morphology of C. zofingiensis cell has changedafter incubation with cellulases and ethanol dehydration indicated degradation of cell wall.

Determination of allelopathic potential in mahogany (Swietenia macrophylla King) leaf litter using sandwich method Arnia Sari Mukaromah; Yekti Asih Purwestri; Yoshiharu Fujii
Indonesian Journal of Biotechnology Vol 21, No 2 (2016)
Publisher : Universitas Gadjah Mada

The sandwich method is a reliable screening bioassay that can be utilized to investigate allelopathic activity of leaf litter leachates. Screening the allelopathic potential of mahogany (Swietenia macrophylla King) leaf litter in plant–plant interaction using the sandwich bioassay method has not been reported. The research objectives were to determine and categorize allelopathic potential of S. macrophylla leaf litter using the sandwich bioassay method, and to determine specific activity (EC550). S. macrophylla leaf litter. The results showed that S. macrophylla leaf litter exhibited strong allelopathic activity when compared with 46 leaf litter species and was included in the top ten of allelopathic leaf litter species. Increasing S. macrophylla leaf litter concentration was concomitant with inhibition of radicle lettuce seedling growth compared with the control. According to the linear regression analysis, the effective concentration (EC50) of S. macrophylla was estimated to be 3.25 mg D.W. eq. mL-1 and was considered to have strong growth-inhibitory activity on lettuce radicle elongation. The results suggest the possibility of allelopathic potential of leaf litter in plant–plant interaction under S. macrophylla trees.

Anthocyanin, nutrient contents, and antioxidant activity of black rice bran of Oryza sativa L. ‘Cempo Ireng’ from Sleman, Yogyakarta, Indonesia Pratiwi Apridamayanti; Rarastoeti Pratiwi; Yekti Asih Purwestri; Woro Anindito Sri Tunjung; Rumiyati Rumiyati
Indonesian Journal of Biotechnology Vol 22, No 1 (2017)
Publisher : Universitas Gadjah Mada

The chemical contents and health benefits of black rice bran of some rice cultivars have been investigated. However, there has been little research on the ‘Cempo Ireng’ cultivar from Sleman, Yogyakarta. The aim of this present study was to determine the anthocyanin, antioxidant activity, and macro- and micronutrients contents of black rice bran from this local cultivar. The anthocyanin in the black rice bran was extracted using the maceration method with methanol as a solvent. The extract obtained was separated through a preparative thin layer chromatography (TLC) of silica GF254 and a mobile phase composed of n-butanol, acetic acid, and water. Two fractions were collected and analyzed for the anthocyanin content. The preparative TLC spots were separated for further detection and measurement of cyanidin 3-O-glucoside using HPLC followed by LC-MS. The antioxidant activity of the fractions were measured using the DPPH free radical scavenging method. The results showed that the anthocyanin in fraction 1 was identified as cyanidin 3-O-glucoside (66.1 ± 10.6 µg/g). The IC50 of fractions 1 and 2 were 200.96 and 218.36 µg/mL, respectively. Analysis of the macro- and micronutrients revealed that the black rice bran of ‘Cempo Ireng’ had nutrient contents comparable with other rice cultivars. Therefore, this local black rice bran can be used as a source of antioxidants and macro-- and micronutrients.

NMR metabolite comparison of local pigmented rice in Yogyakarta Dio N. Wijaya; Febri Adi Susanto; Yekti Asih Purwestri; Dyah Ismoyowati; Tri Rini Nuringtyas
Indonesian Journal of Biotechnology Vol 22, No 2 (2017)
Publisher : Universitas Gadjah Mada

Pigmented rice may have a black or red color due to higher anthocyanin content in its grain. A natural antioxidant, many studies on anthocyanin have reported its positive effects on human health. This fact has spurred the development of pigmented rice as a functional food. This study aimed to compare the metabolite profiles of black and red rice. Three black rice cultivars, namely Melik, Pari Ireng, and Cempo Ireng Sleman, and two red rice cultivars, Inpari 24 and RC 204, were used. After husk removal, grain samples were ground in liquid nitrogen and dried with a freeze dryer. The dried samples were extracted using 50% MeOD4 (in a D2O phosphate buffer pH 6 containing 0.01% TSP as an internal standard). Metabolomic analysis was performed using 500 MHz NMR followed by multivariate data analysis. An orthogonal partial least squares-discriminant analysis (OPLS-DA) model ađer PCA was constructed to discriminate between the five different cultivars. The resulting OPLS-DA score plot revealed a clear separation between black rice and red rice. The metabolites that could influence the separation of red rice and black rice were valine, threonine, alanine, glutamate, galactinol, β-glucose, α-glucose, raffinose, and fumaric acid.

Decolorization and detoxification of batik dye effluent containing Indigosol Blue-04B using fungi isolated from contaminated dye effluent Ratna Stia Dewi; Rina Sri Kasiamdari; Erni Martani; Yekti Asih Purwestri
Indonesian Journal of Biotechnology Vol 23, No 2 (2018)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijbiotech.32332

Fungi are capable of treating various synthetic dye effluents. Previously, we isolated seven strains of fungi from contaminated batik dye effluent at Banyumas, Central Java. The aims of this study were to screen the ability of these fungi to decolorize batik dye effluents containing Indigosol Blue-04B and to investigate the phytotoxicity effects of biodegraded effluent on the germination of corn seeds Zea mays L. and green bean seeds Vigna radiata (L.) Wilczek. In addition, the decolorized effluents were tested for toxic effect on the agriculturally important gram-positive and gram-negative soil bacteria Bacillus cereus and Azotobacter sp., Staphylococcus aureus and Escherichia coli, respectively. Study of decolorization showed that fungi were able to decolorize Indigosol Blue-04B batik dye effluents by 21.04% to 99.89% at room temperature after three days of incubation. The assay of phytotoxicity showed that both plumule and radicle length of Z. mays and V. radiata grown on the decolorized effluent was longer than on untreated effluent. The percentage of Z. mays and V. radiata seed germination in decolorized effluent was higher than in untreated effluent. There was no inhibition zone found around the decolorized effluent samples after incubating the bacteria for 48 hours. Aspergillus sp. 3 was the most effective for degradation and could be used for batik effluent mycoremediation processes.

Amylolytic ability of bacteria isolated from termite (Coptotermes sp.) gut Putri Dwi Mulyani; Radhiyah Mardhiyah Hamid; Rifqi Zahroh Janatunaim; Yekti Asih Purwestri
Indonesian Journal of Biotechnology Vol 23, No 1 (2018)
Publisher : Universitas Gadjah Mada

BSR 2, BSR 3, BSR 8, and BSR 9, different bacteria isolated from the termite gut, have been shown to possess cellulolytic activities, but their amylolytic ability has heretofore been unknown. This study attempted to fill in this knowledge gap. The formation of a clear zone using the iodine test showed that the bacteria were able to produce and secrete amylase. Based on the results, the best cultivation times for strains BSR 2, BSR 3, BSR 8, and BSR 9 were 6, 3, 2, and 2 d, respectively, yielding amylase activities of 2.59 ± 0.13 U/mg, 2.00 ± 0.08 U/mg, 1.67 ± 0.10 U/mg, and 1.55 ± 0.12 U/mg, respectively. BSR 2 had the highest amylase activity compared with the other bacterial isolates. The optimum ph for bacterial amylase activity of BSR 2 was 7.0, and the optimum temperature was 40°C. The molecular characterization of isolates BSR 2, BSR 3, BSR 8, and BSR 9 was based on 16S rRNA gene sequences. Isolates BSR 8 and BSR 9 were thus identified as Brevibacillus parabrevis and Brevibacillus sp. With similarities amounting to 92.48% and 95.91%, while the BSR 3 isolate was identified as Pseudomonas alcaligenes with a similarity of 94.29%, and the BSR 2 isolate could not be identified yet.

Plant growth‐promoting activity of endophytic bacteria from sweet sorghum (Sorghum bicolor (L.) Moench) Charlie Ester de Fretes; Donny Widianto; Yekti Asih Purwestri; Tri Rini Nuringtyas
Indonesian Journal of Biotechnology Vol 26, No 4 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijbiotech.64893

Application of high levels of chemical fertilizers for optimal growth of sweet sorghum causes environmental degradation. Plant growth‐promoting bacteria have biotechnological importance because they can improve the growth and health of important agronomic plants. This study aimed to isolate, characterize, and identify endophytic bacteria associated with sweet sorghum (cv. KCS105), and also to study the inoculation effects of selected isolates on sorghum growth. In this study, 35 isolates were evaluated for their ability to support plant growth. The results showed that seven isolates were diazotrophic, six were capable of dissolving phosphate, six produced IAA and could detect ACC‐deaminase activity, and three inhibited the growth of pathogenic fungi. Nine isolates exhibiting mechanisms for promoting plant growth from the Alphaproteobacteria (Devosia), Firmicutes (Bacillus, Paenibacillus, Staphylococcus), and Actinobacteria (Microbacterium, Brachybacterium) phyla were identified. In addition, the Paenibacillus sp. BB7, Bacillus sp. PIB1B, and Bacillus sp. PLB1B isolates showed increasing effects on plant growth in greenhouse tests. Endophytic bacterial isolates which display plant growth‐promoting features can potentially be employed as biofertilizer agents. They may also address environmental damage problems resulting from the use of chemical fertilizers and pesticides.

The relationship between morpho‐physiological changes and expression of transcription factors in NTT local rice cultivars as a response to drought stress Yustina Carolina Febrianti Salsinha; Alfino Sebastian; Ekris Sutiyanti; Yekti Asih Purwestri; Didik Indradewa; Diah Rachmawati
Indonesian Journal of Biotechnology Vol 27, No 1 (2022)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijbiotech.65728

Response by plants to drought occurs through a series of mechanisms that involve transcription regulation. This research was conducted to study transcription factors (TF) and physiological changes in the drought response of local rice cultivars from East Nusa Tenggara (Nusa Tenggara Timur, NTT) during drought stress. Using three NTT local rice cultivars (Boawae Seratus Malam (BSM), Gogo Jak (GJ), and Kisol Manggarai (KM)) and the fraction of transpirable soil water (FTSW) method with two treatment levels, FTSW 1 (control) and FTSW 0.2 (severe stress), we analyzed the TF expression of OsDREB1A, OsDREB2A, OsWRKY45, and OsNAC6. Based on the result, the highest level of TF expression occurred in the BSM, followed by the GJ and KM cultivars. Analysis of physiological characteristics showed an association between TF expression levels and physiological response, with the BSM cultivar showing high pigment levels, high proline content, and lower H2O2 levels. A linkage was also found in relation to water conservation, as indicated by the higher relative water content and cell membrane stability index in the BSM cultivar in contrast to lower electronic leakage and malondialdehyde percentage when exposed to drought. Based on the results, it can be concluded that the BSM cultivar can be considered as a drought‐tolerant local cultivar according to morpho‐physiological analysis. In this study, all NTT local rice cultivars showed a subtle upregulation of stress‐responsive transcription factors OsDREB1A, OsDREB2A, OsWRKY45, and OsNAC6 as responses to drought stress.

Identification of mercury‐resistant Streptomyces isolated from Cyperus rotundus L. rhizosphere and molecular cloning of mercury (II) reductase gene Wahyu Aristyaning Putri; Hanum Mukti Rahayu; Anis Uswatun Khasanah; Langkah Sembiring; Masashi Kawaichi; Yekti Asih Purwestri
Indonesian Journal of Biotechnology Vol 26, No 4 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijbiotech.65989

Streptomyces is one of mercury‐resistant bacteria which can convert Hg2+ into nontoxic Hg0 . This study aimed to identify mercury‐resistant Streptomyces present in the Cyperus rotundus rhizosphere from artisanal small‐scale gold mining (ASGM) area and clone merA gene to the cloning and expression vectors. Molecular identification was conducted using 16s rRNA gene with the maximum likelihood algorithms. Results revealed that the AS1 and AS2 strains were a group of Streptomyces ardesiacus and the BR28 strain was closed to Brevibacillus agri. The AS2 merA gene was cloned to pMD20 cloning vectors, pGEX‐5x‐1 and pET‐28c expression vectors. The transformation was successfully performed in BL21 and DH5α competent cells. The full length of the merA gene was confirmed to be 1,425 bp. This study is the first research on identifying mercury‐resistant Streptomyces and cloning the full‐length merA gene in Indonesia.

Co-Authors Abdul Rahman Siregar, Abdul Rahman Adania, Baik Aisyah Agung Endro Nugroho Alfino Sebastian Alfino Sebastian Alfino Sebastian Almunawar, Muhammad Fikri Andi Setiawan Anis Uswatun Khasanah Anjar Tri Wibowo Aprilianti, Suci Hari Ardaning Nuriliani Ari Indrianto Arnia Sari Mukaromah Bassalamah, Rizka Fahma Budi Setiadi Daryono Cahyo Wulandari Caroline Dwiseptianti Charlie Ester de Fretes Diah Rachmawati Dian Resti Setyaningrum Didik Indradewa Didik Indradewa Didik Indradewa Dio N. Wijaya Donny Widianto Donny Widianto Dwiseptianti, Caroline Dyah Ismoyowati, Dyah Ekowati, Nurhening Yuni Ekris Sutiyanti Elvani, I Sabila Endang Semiarti Erni Martani Erni Martani Erwin Nur Indiarto Fajar Sofyantoro Febri Adi Susanto Febri Adi Susanto Ghea Putri Christy Hidayat, Rheina Faticha Asyamsa Himawan, Tyas Ikhsan Hiroyuki Tsuji Hiroyuki Tsuji, Hiroyuki Ikhsan Maulana Khasanah, Anis Uswatun Ko Shimamoto Ko Shimamoto, Ko Kumala Dewi Kumala Dewi Langkah Sembiring Langkah Sembiring LANGKAH SEMBIRING Latifah, Emi Lila Natasaputra Lila Natasaputra, Lila Lisna Hidayati, Lisna Maharesi, Chesa Ekani Masashi Kawaichi Mataram, Made Bagus Auriva Muhammad Rizky Ulil Albab Mulyani, Putri Dwi Nasution, Nurlita Putri Bela Nugrahapraja, Husna Nurhidayah, Septika P. Parmi Parmi P, Parmi Pratiwi Apridamayanti Pratiwi, Apriliana Priyono, Dwi Sendi Putri Dwi Mulyani Putri Dwi Mulyani Putri Wijayanti Putri, Wahyu Aristyaning Rachman, Mifta Pratiwi Radhiyah Mardhiyah Hamid Radhiyah Mardhiyah Hamid Rahayu, Hanum Mukti Rarastoeti Pratiwi Rarastoeti Pratiwi Ratna Dewi Eskundari Ratna Stia Dewi Ratna Stia Dewi Respati Tri Swasono Retnowati, Faizah Diah Rifqi Zahroh Janatunaim Rifqi Zahroh Janatunaim Rina Sri Kasiamdari Rosy Feraningsih Patigu Rumiyati Rumiyati Rumiyati Saragih, Hendry T.S.S.G Satrijo Saloko Sebastian, Alfino Sine, Yuni Siti Nurbaiti Siti Subandiyah Sofyana, Neng Tanty Sri Widyastuti Sri Widyastuti Subiastuti, Aprilia Sufi Susanto, Febri Adi Syam, Adi Mazdi Taryono Taryono Taryono, Taryono Tri Rini Nuringtyas Tri Rini Nuringtyas Triastuti Rahayu Triyaningsih Triyaningsih Triyaningsih, Triyaningsih Wahyu Aristyaning Putri Woro Anindito Sri Tunjung Yohana Theresia Maria Astuti Yohana Theresia Maria Astuti, Yohana Theresia Maria Yoshiharu Fujii Yosi Bayu Murti Yudi Pranoto Yuka Ogaki Yuka Ogaki, Yuka Yustina Carolina Febrianti Salsinha

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