Papers by Ruth Chrisnasari
E3S web of conferences, 2023
The purpose of this study was to determine the effect of Organic and Non-Organic Balinese Cacao (... more The purpose of this study was to determine the effect of Organic and Non-Organic Balinese Cacao (Theobroma cacao L.) storage duration on chemical and microbiological levels in order to know the exact storage period to get a good substrate for fermentation. This research is the first step in preparing Specialty Cocoa. Chemical parameters such as reducing sugar, total sugar, protein content, moisture content, and pH along the pod storage were determined in this study. The ideal substrate condition for cocoa fermentation was suggested on the 4 th d, in which the pulp contained total sugar of 12.5 % and moisture content of 86 %. Meanwhile, the statistical analysis was done to test whether the duration of pod storage has a significant effect on the presence of bacteria related to fermentation. The test showed that the duration of pod storage did not have a significant effect on either lactic acid bacteria or acetic acid bacteria content (P value > 0.05). Nevertheless, the research found that lactic acid bacteria content was up to 1.9 log CFU mL-1 and acetic acid bacteria content was up to 2.72 log CFU mL-1 during the 5 d of pod storage.
CALYPTRA, Mar 1, 2018
Minyak kelapa dapat mengalami ketengikan selama proses penggunaan. Ketengikan pada minyak kelapa ... more Minyak kelapa dapat mengalami ketengikan selama proses penggunaan. Ketengikan pada minyak kelapa dapat terjadi karena proses oksidasi. Untuk mencegah proses oksidasi pada minyak, umumnya digunakan senyawa antioksidan. Antioksidan sintetik sangat umum digunakan sebagai pengawet minyak komersial, namun antioksidan sintetik diketahui dapat menyebabkan gangguan kesehatan. Untuk itu, pada penelitian ini dilakukan studi penambahan antioksidan alami dari ekstrak kasar daun teh hitam terhadap mutu minyak kelapa yang diberi perlakuan untuk mempercepat ketengikan. Daun teh hitam diekstraksi menggunakan 3 jenis pelarut yang berbeda untuk menentukan pelarut terbaik dalam mengekstrak antioksidan dari daun teh hitam yang memberikan aktivitas antioksidan tertinggi. Didapatkan bahwa pelarut terbaik dalam mengekstrak daun teh hitam adalah etanol 96% dengan aktivitas antioksidan sebesar 75,01%. Ekstrak kasar daun teh hitam sebanyak 0,01% (v/v) kemudian digunakan untuk perlakuan pada minyak kelapa dalam mencegah kerusakan minyak. Dilakukan pengujian terhadap beberapa parameter fisik dan kimia minyak kelapa, diantaranya angka iodium, angka peroksida, angka TBA, serta perubahan warna dan viskositas. Hasil pengujian parameter fisik dan kimia minyak kelapa menunjukkan bahwa penambahan ekstrak kasar daun teh hitam dapat menghambat laju oksidasi minyak dibandingkan dengan kontrol (tanpa penambahan ekstrak kasar). Berdasarkan hasil penelitian, efisiensi antioksidan dari ekstrak kasar daun teh hitam adalah sebesar 1,5. Abstract -Coconut oil can undergo rancidity during the usage. Rancidity in coconut oil can occur due to the oxidation process. Antioxidant mostly used to prevent oil oxidation. Synthetic antioxidant usually used as a preservative in commercial oil, however synthetic antioxidant had been known to cause several health problems. Therefore, this research was aimed to study the addition of antioxidant from crude extract of black tea leaves in coconut oil quality which treated to accelerate its rancidity. Black tea leaves were extracted using 3 different solvents to determine the best solvent to extract the antioxidant from black tea leaves which gave the highest antioxidant activity. The best solvent to extract the black tea leaves was found to be ethanol 96% with the antioxidant activity of 75,01%. As much as 0,01% (v/v) crude extract of black tea leaves then used for treatment to prevent the deterioration of coconut oil. The oil quality was assessed by measuring iodine value, peroxide value, TBA value and the change in colour and viscosity. The results showed that the addition of crude extract from black tea leaves delayed the oxidation rate in coconut oil compared to the control (without extract addition). The antioxidant efficiency of crude extract from black tea leaves was 1,5.
UNEJ e-Proceeding, Oct 1, 2014
The influence of bentonite modification by cationic surfactant hexadecyl-trimethyl-ammonium bromi... more The influence of bentonite modification by cationic surfactant hexadecyl-trimethyl-ammonium bromide (HDTMA-Br) and tetramethyl ammonium hydroxide (TMAOH) on its capability to immobilize lipase was studied. Modification of bentonite was conducted by the adding of 4-6% (v/v) HDTMA-Br and TMAOH respectively. The obtained immobilized lipases then were characterized to observe the optimum pH and temperature as well as their stability during reuse application. The observed results show that there is no significant difference between the variations of HDTMA-Br concentrations to the percentage of immobilized enzyme which can immobilize lipase up to 75-78%. However, the best concentration of TMAOH is 4% (v/v) which can immobilize lipase up to 97.95%. The obtained immobilized lipases on HDTMA-Br-modified bentonite show the optimum catalytic activity on reaction temperature of 35-40 o C and pH of 7.5. In other hand, the optimum catalytic activity of immobilized lipases on TMAOH-modified bentonite is 40 o C of incubation temperature and pH of 7. The immobilized lipases on both HDTMA-Br and TMAOH modified bentonite are stable enough so it could be re-used four times before its activity decreased by 48,565% and 46.83 % respectively.
Microbiology Indonesia, Mar 1, 2013
Two different process configurations, simultaneous saccharification and fermentation (SSF) and se... more Two different process configurations, simultaneous saccharification and fermentation (SSF) and separate hydrolysis and fermentation (SHF), were compared for ethanol production from Shorgum bicolor grain. Optimization modeling for glucoamylase and Zymomonas mobilis concentration in both of SSF and SHF were carried out to obtain optimal concentration of ethanol production. The optimum condition was achieved using 0.021 % v/v of glucoamylase and 30.19% v/v of Zymomonas mobilis for SHF. In contrast, the optimum condition for SSF was 0.021 % v/v of glucoamylase and 17.51% v/v of Zymomonas mobilis. The model predicted SHF processing to be superior. The superiority of SHF over SSF was confirmed experimentally, the result showed ethanol yield of SHF was 134.80 g/L and ethanol yield of SSF was 115.66 g/L after 72 hours incubation time. A high similarity was observed between the predicted and experimental results, demonstrating the accuracy of the model.
![Research paper thumbnail of The effect of fermentation process on physical and chemical characteristics of pitaya (Hylocereus polyrhiuzus [F.A.C. Weber] Britton & Rose) stem flour](https://attachments.academia-assets.com/117484136/thumbnails/1.jpg)
IOP conference series, Jun 1, 2019
Research interest on fiber has increased rapidly in the last decade due to its complexity and fun... more Research interest on fiber has increased rapidly in the last decade due to its complexity and functional properties towards the human body. In this research group, pitaya (Hylocereus polyrhiuzus [F.A.C. Weber] Britton & Rose) stem flour is a promising candidate as new food resources since it contains a high amount of fiber and vitamin C as well as demonstrates both antioxidant and antibacterial activities. However, this pitaya stem flour has very low solubility in water that makes its application in food product very limited. In this study, pitaya stem flour has been fermented by Trichoderma reesei in a variation of inoculum concentration (3 % and 5 %) and fermentation time (24 to 60 h). The fermentation processes reduce the ash and water content of the flour, increase the soluble fiber content as well as its solubility. During the fermentation, the colour of the flour has changed. It becomes brighter and brownish. The best fermentation condition marked by its highest soluble fiber content is achieved by 3 % (w/v) of T. reesei inoculum with 60 h incubation time.
Red pitaya fruit and peel have been widely explored for food products due to their functional pro... more Red pitaya fruit and peel have been widely explored for food products due to their functional properties. However, the stem still has limited use. This work was aimed to determine the proximate and phytochemical properties of red pitaya stem by processing it as flour and applied it as food products. The different drying temperature (40, 50, 60ºC) on the flouring process was conducted to determine the best drying condition. The best drying temperature was then used to prepare the flour by using whole stem (epidermis and cortex)
Journal of Mathematical and Fundamental Sciences, Aug 1, 2016
Thermophilic bacteria producing chitinase were collected from Prataan hot spring, East Java, Indo... more Thermophilic bacteria producing chitinase were collected from Prataan hot spring, East Java, Indonesia and screened. The isolated bacterium was analyzed using 16S rRNA gene sequencing analysis and identified as Paenibacillus sp. The molecular identification was confirmed through morphological and physiological analyses. The production of chitinase was conducted at various incubation times, temperatures, pH and concentrations of colloidal chitin. The optimum condition of the isolate to produce the highest chitinase was 0.9% (w/v) of colloidal chitin (pH 7.0) at 48 °C for 24 hours. The obtained chitinases were optimally active at 55 °C and pH 6.0-7.0. The chitinases were gradually purified by ammonium sulfate precipitation, Sephadex G-100 gel filtration, followed by DEAE-cellulose ion exchange chromatography (IEC). The purification method gave a purification factor of 9.43 and a yield of 2.68%. Two protein fractions were obtained from sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE) with molecular weights of 68 and 82 kDa.
CALYPTRA, 2019
Coconut oil can be used to fulfill the high demand for cooking oil in Indonesia. The quality of c... more Coconut oil can be used to fulfill the high demand for cooking oil in Indonesia. The quality of coconut oil can decrease because of oxidation. Oxidation can be prevented by adding natural antioxidant such as green tea. The objective of this research was to optimize the process of metabolite extraction with highest antioxidant activity. The solvent used for extraction were ethanol 96%, asetonitril 50% and acetone 25%. Green tea extract was analyzed quantitatively using Total Phenolic Compound (TPC) and 2,2-diphenyl-1-pichrylhydraziyl (DPPH). The crude extract from green tea from maceration using ethanol 96% gave the highest inhibition at about 90,8 ± 0,71%. Thin Layer Chromatography (TLC) analysis showed existence of catechin and myrecetin in the extract. As much as 0,01% was applied as natural antioxidant in coconut oil. The quality of coconut oil observed by iodine value, peroxide value, TBA value, colour and viscosity changed. The result showed that the addition of green tea extract can prevent oxidation rate with efficiency of 1,5.
Paenibacillus sp. isolat D merupakan salah satu bakteri penghasil kitinase termostabil yang berpo... more Paenibacillus sp. isolat D merupakan salah satu bakteri penghasil kitinase termostabil yang berpotensi untuk digunakan di industri konversi kitin. Penelitian ini bertujuan untuk mengetahui tipe gen-gen pengkode kitinase yang ada pada Paenibacillus spp. dan dari tipe-tipe tersebut dapat dibuat degenerate primer untuk mendeteksi keberadaan gengen pengkode kitinase pada Paenibacillus sp. isolat D melalui teknik Polymerase Chain Reaction (PCR). Degenerate primer digunakan dengan mempertimbangkan adanya keterbatasan informasi mengenai sekuen lengkap dari genom isolat D, adanya codon bias, dan variabilitas pada daerah conserved gen pengkode kitinase. Pengelompokan hasil identifikasi gen-gen pengkode kitinase dari database Paenibacillus spp. di National Center of Biotechnology Information (NCBI) menunjukkan bahwa kitinase Paenibacillus spp. tersebar pada dua famili glikosil hidrolase (GH) yaitu GH18 dan GH19. Adapun sembilan kelompok conserved domain spesifik teridentifikasi dari kelompok GH18. Degenerate primer didesain dengan HYDEN dan Geneious R8 dari tiga kelompok domain terbesar. Tiga pasang degenerate primer yang diperoleh yaitu ChiA_8915_2, ChiD_5915_1, dan GH19_5915_1 digunakan untuk deteksi dengan PCR. Berdasarkan hasil analisis dengan teknik PCR menggunakan ketiga pasang primer degenerate dan hasil analisis sekuensing, keberadaan gen-gen pengkode kitinase pada Isolat D belum dapat ditentukan. Dari tiga pasang primer tersebut, hanya pasangan primer ChiA_8915_2 yang diketahui dapat mendeteksi gen pengkode kitinase yaitu pada domain target yaitu ChiA.
Applied microbiology and biotechnology, Mar 18, 2024
Lipoxygenases (LOXs) catalyze dioxygenation of polyunsaturated fatty acids (PUFAs) into fatty aci... more Lipoxygenases (LOXs) catalyze dioxygenation of polyunsaturated fatty acids (PUFAs) into fatty acid hydroperoxides (FAHPs), which can be further transformed into a number of value-added compounds. LOXs have garnered interest as biocatalysts for various industrial applications. Therefore, a high-throughput LOX activity assay is essential to evaluate their performance under different conditions. This study aimed to enhance the suitability of the ferrous-oxidized xylenol orange (FOX) assay for screening LOX activity across a wide pH range with different PUFAs. The narrow linear detection range of the standard FOX assay restricts its utility in screening LOX activity. To address this, the concentration of perchloric acid in the xylenol orange reagent was adjusted. The modified assay exhibited a fivefold expansion in the linear detection range for hydroperoxides and accommodated samples with pH values ranging from 3 to 10. The assay could quantify various hydroperoxide species, indicating its applicability in assessing LOX substrate preferences. Due to sensitivity to pH, buffer types, and hydroperoxide species, the assay required calibration using the respective standard compound diluted in the same buffer as the measured sample. The use of correction factors is suggested when financial constraints limit the use of FAHP standard compounds in routine LOX substrate preference analysis. FAHP quantification by the modified FOX assay aligned well with results obtained using the commonly used conjugated diene method, while offering a quicker and broader sample pH range assessment. Thus, the modified FOX assay can be used as a reliable high-throughput screening method for determining LOX activity. • Modifying perchloric acid level in FOX reagent expands its linear detection range • The modified FOX assay is applicable for screening LOX activity in a wide pH range • The modified FOX assay effectively assesses substrate specificity of LOX Keywords Fatty acids • FOX assay • High-throughput screening • Hydroperoxides • Lipoxygenase * Tom A. Ewing
Biotechnology Advances, Dec 1, 2022
Lipoxygenases (LOXs) are enzymes that catalyze dioxygenation of polyunsaturated fatty acids into ... more Lipoxygenases (LOXs) are enzymes that catalyze dioxygenation of polyunsaturated fatty acids into fatty acid hydroperoxides. The formed fatty acid hydroperoxides are of interest as they can readily be transformed to a number of value-added compounds. LOXs are widely distributed in both eukaryotic and prokaryotic organisms, including humans, animals, plants, fungi and bacteria. Compared to eukaryotic enzymes, bacterial enzymes are typically easier to produce at industrial scale in a heterologous host. However, many bacterial LOXs were only identified relatively recently and their structure and biochemical characteristics have not been extensively studied. A better understanding of bacterial LOXs' structure and characteristics will lead to the wider application of these enzymes in industrial processes. This review focuses on recent findings on the biochemical characteristics of bacterial LOXs in relation to their molecular structure. The basis of LOX catalysis as well as emerging determinants explaining the regio-and enantioselectivity of different LOXs are also summarized and critically reviewed. Clustering and phylogenetic analyses of bacterial LOX sequences were performed. Finally, the improvement of bacterial LOXs by mutagenesis approaches and their application in chemical synthesis are discussed.
KELUWIH: Jurnal Sains dan Teknologi, Feb 28, 2020
Starch-degrading enzymes not only can be found in bacteria and fungi, but also in plants. Some pl... more Starch-degrading enzymes not only can be found in bacteria and fungi, but also in plants. Some plants that produce starch-degrading enzymes are germinated grain of sorghum, maize, and mung bean. pH and temperature are factors that can affect the activity of enzyme. Effect of pH and temperature to starch-degrading enzyme activity of these 3 cereal grains are reported in this research. Grain of sorghum, maize, and mung bean were germinated for 2 days and dried to produce malt. Enzymes from these 3 different malts were extracted using 7 buffers with different pH (4
E3S Web of Conferences
The high industrial demand for thermostable chitinase with new and desirable characteristics has ... more The high industrial demand for thermostable chitinase with new and desirable characteristics has led to the exploration of chitinolytic bacteria from extreme environments. Therefore, this study aimed to isolate, screen, and identify chitinase–producing bacteria from Ijen hot spring, Indonesia. The highest chitinolytic activity bacterium was identified by 16S rRNA gene sequencing and its characteristics were confirmed by morphological and physiological analyses. Chitinase production activity of selected bacterium under variation of agitation and aeration as well as its chitinase properties were characterized afterward. Twelve chitinolytic bacterial colonies were isolated and screened for their growth activity on Thermus colloidal chitin medium, in which chitin was used as the sole carbon source. Among these twelve isolates, isolate B2 showed the highest chitinolytic activity. The molecular, morphological, and physiological analyses confirmed that isolate B2 belonged to Bacillus liche...
Pemanfaatan enzim Glukosa Oksidase (GOD) terus berkembang baik dalam bidang industri maupun dalam... more Pemanfaatan enzim Glukosa Oksidase (GOD) terus berkembang baik dalam bidang industri maupun dalam bidang medis, biosensor, dan sebagainya. Secara teknis sangat sulit untuk memisahkan enzim dan produk dan mendapatkan kembali enzim yang aktif diakhir reaksi, sehingga dilakukan imobilisasi enzim. Salah satu bahan alam yang dapat digunakan untuk imobilisasi adalah bentonit. Untuk meningkatkan kemampuan bentonit dalam mengimobilisasi enzim, dilakukan modifikasi bentonit berupa penambahan surfaktan Tetrametil Ammonium Hidroksida (TMAOH). Penambahan surfaktan pada bentonit menggunakan TMAOH dilakukan dengan memanaskan campuran bentonit dan TMAOH pada suhu 75oC selama 5 jam. Penambahan TMAOH dilakukan dengan perbandingan bentonit alam : larutan Tetrametil Ammonium Hidroksida (TMAOH) adalah 1 - 5 gram : 100 mL dan konsentrasi Tetrametil Ammonium Hidroksida (TMAOH) adalah 0,75% - 5,0% (v/v). Imobilisasi enzim GOD dilakukan dengan cara mencampurkan larutan enzim dengan bentonit teraktifkan den...
INTERNATIONAL CONFERENCE ON INFORMATICS, TECHNOLOGY, AND ENGINEERING 2021 (InCITE 2021): Leveraging Smart Engineering
Hydrochloric acid was used to prepare bentonite carrier for xylanase immobilization from Trichode... more Hydrochloric acid was used to prepare bentonite carrier for xylanase immobilization from Trichoderma reesei as green biocatalyst. The process to produce xylanase from Reutealis trisperma was carried out for 72 hours in batch fermentation at initial pH of 6.0. The xylanase activity was 205.9±0.84 U/mL. It was then purified and analyzed using SDS-PAGE and found to be 26 and 32 kDa. The purification yield was 31.32 %. The bentonite carrier with 140 mesh particle size was pretreated at various HCl concentration. The impurities consist of several ions were successfully replaced by H + ion as confirmed by FTIR spectra. The carrier was used to immobilize xylanase and the best carrier used in immobilization was bentonite with 2M HCl concentration pretreatment. The best final immobilization was 87.765 % and the leaching was 0.059 %. The biocatalyst can be proposed as green biocatalyst to reduce chlorine used in pulp bleaching.
CALYPTRA, Mar 1, 2018
Minyak kelapa dapat mengalami ketengikan selama proses penggunaan. Ketengikan pada minyak kelapa ... more Minyak kelapa dapat mengalami ketengikan selama proses penggunaan. Ketengikan pada minyak kelapa dapat terjadi karena proses oksidasi. Untuk mencegah proses oksidasi pada minyak, umumnya digunakan senyawa antioksidan. Antioksidan sintetik sangat umum digunakan sebagai pengawet minyak komersial, namun antioksidan sintetik diketahui dapat menyebabkan gangguan kesehatan. Untuk itu, pada penelitian ini dilakukan studi penambahan antioksidan alami dari ekstrak kasar daun teh hitam terhadap mutu minyak kelapa yang diberi perlakuan untuk mempercepat ketengikan. Daun teh hitam diekstraksi menggunakan 3 jenis pelarut yang berbeda untuk menentukan pelarut terbaik dalam mengekstrak antioksidan dari daun teh hitam yang memberikan aktivitas antioksidan tertinggi. Didapatkan bahwa pelarut terbaik dalam mengekstrak daun teh hitam adalah etanol 96% dengan aktivitas antioksidan sebesar 75,01%. Ekstrak kasar daun teh hitam sebanyak 0,01% (v/v) kemudian digunakan untuk perlakuan pada minyak kelapa dalam mencegah kerusakan minyak. Dilakukan pengujian terhadap beberapa parameter fisik dan kimia minyak kelapa, diantaranya angka iodium, angka peroksida, angka TBA, serta perubahan warna dan viskositas. Hasil pengujian parameter fisik dan kimia minyak kelapa menunjukkan bahwa penambahan ekstrak kasar daun teh hitam dapat menghambat laju oksidasi minyak dibandingkan dengan kontrol (tanpa penambahan ekstrak kasar). Berdasarkan hasil penelitian, efisiensi antioksidan dari ekstrak kasar daun teh hitam adalah sebesar 1,5. Kata Kunci : antioksidan alami, daun teh hitam, ekstraksi antioksidan, minyak kelapa Abstract-Coconut oil can undergo rancidity during the usage. Rancidity in coconut oil can occur due to the oxidation process. Antioxidant mostly used to prevent oil oxidation. Synthetic antioxidant usually used as a preservative in commercial oil, however synthetic antioxidant had been known to cause several health problems. Therefore, this research was aimed to study the addition of antioxidant from crude extract of black tea leaves in coconut oil quality which treated to accelerate its rancidity. Black tea leaves were extracted using 3 different solvents to determine the best solvent to extract the antioxidant from black tea leaves which gave the highest antioxidant activity. The best solvent to extract the black tea leaves was found to be ethanol 96% with the antioxidant activity of 75,01%. As much as 0,01% (v/v) crude extract of black tea leaves then used for treatment to prevent the deterioration of coconut oil. The oil quality was assessed by measuring iodine value, peroxide value, TBA value and the change in colour and viscosity. The results showed that the addition of crude extract from black tea leaves delayed the oxidation rate in coconut oil compared to the control (without extract addition). The antioxidant efficiency of crude extract from black tea leaves was 1,5.
KELUWIH: Jurnal Sains dan Teknologi, 2022
Okra is one of vegetable that rarely used by Indonesian people, whereas it is healthty because of... more Okra is one of vegetable that rarely used by Indonesian people, whereas it is healthty because of its high antioxidant and fiber content. Water kefir is a fermented product that used fruit and vegetables as its substrate.This study aims to determine the type of okra treatment (soaked and juiced) and honey concentration (0%, 4% and 8%) on physicochemical, microbiology and organoleptic characteristics of water kefir. This study used a randomized group design method with variations on okra treatment and concentration of honey. Based on the results of physicochemical tests, okra treatment and honey concentration have an interaction and significantly influence the parameters of total sugar, total dissolved solids, lactic acid levels, total acid, pH, antioxidant activity, ethanol levels, total LAB and total yeast. Organoleptic test showed okra treatment and concentration of honey significantly influence the parameters of color, flavor, taste and aftertaste. Soaked okra kefir with 8% honey is the best result using the effectiveness index based on psycochemical and organoleptic test. The best treatment has a characteristic product of light yellow, less acidic aroma, quite sweet taste, less alcoholic taste and not bitter aftertaste.
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Papers by Ruth Chrisnasari