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Abstrak :
Palm Kernel Meal is solid waste from Palm Oil extraction (Ng, 2003). Akubuo & Eje (2002) reported that mechanical extraction produced Palm Kernel Oil (PKO) dan Palm Kernel Meal (PKM). Perez (1997) mentioned that Palm Kernel Meal contains rich arginin, leusin, and sistein matters. Hem et al., (2008), utilizing Palm Kernel Meal pass through bioconversion process for developing larvae Hermetia illucens L. as alternative natural feedstuff in aquaculture industry. Macromolecule composition of Palm Kernel Meal like cellulose, hemicellulose and lignin can be degrade to be simply compound and can be used by another organism like larvae Hermetia illucens L. in bioconversion process. Bioconversion Palm Kernel Meal for feedstuff nutrition consist with microorganism assistance. Suharyanto et al., (2006) define bioconversion as a certain biological process which involving microorganism or enzyme that can change organic matters. Slime molds have great play role in process reduction macromolecule composition of Palm Kernel Meal. Molds have enzyme which can reduce cellulose, hemicellulose and lignin become more simple compound. Study about fermentation fungi already been done through isolation, identification, and fungi screening. However, only a few study about fungi related consist in process bioconversion Palm Kernel Meal reported in Indonesia. This study consist of two part. First part describes the isolation, identification, and growth screening fungi from bioconversion Palm Kernel Meal. Second part of this study describes the fermentation Palm Kernel Meal by selected indigenous fungi. The selected indigenous fungi obtained from result of the first part. The fermentation result included ash matters, crude fiber, crude protein and dry matters experiment. The study was carried out at the Institut de Recherche pour le Developpement (IRD) Laboratory, Depok and the Laboratory of Microbiology, Departement of Biology, UI, Depok during April?Oktober 2009. The isolation of fungi was conducted with spread methods on Potato Dectrose Agar (PDA). Identification of the isolates was carried out on Potato Dectrose Agar (PDA), Czapeck Dox Agar (CDA), and Malt Extract Agar (MEA) based on macroscopic and microscopic morphological observation of the colonies. The Mimura agar (MA) was used for growth fungi screening. The isolation resulted in 15 representative isolates consisting of 4 group of fungi (Aspergillus, Mucor, Penicillium, and Geotrichum). Based on 7 days periods of fermentation processing, Mucor groups had the highest frequency distribution and Geotrichum had the highest quantity. After the growth fungi screening, 4 isolates (P3, P4, P10, P15) was selected for futher study in part II. Microscopic identification showed P3 (Penicillium chrysogenum), P4 (Mucor racemosus), P10 (Aspergillus flavus), and P15 (Geotrichum candidum). Mucor racemosus was the most wide diameter colony on Mimura agar?MA (9 cm) comparing to other isolates. These selected fungi was used for fermentation of Palm Kernel Meal as inoculant. After process bioconversion which fermented was done, proximate analysis were carried out to examine crude protein, crude fiber, ash matters, and dry matters. Ng (2003) methods was used for this Palm Kernel Meal fermentation and Hart & Fisher (1971) was used for proximate analysis. The results after 7 days fermentation showed that the increased nutrition of crude protein composition of Palm Kernel Meal fermented by fungus Aspergillus flavus (1,33%), Geotrichum candidum (5,90%), Mucor racemosus (0,29%), and Penicillium chrysogenum (12,09%). The increased crude fiber contains fermented by Aspergillus flavus (3,03%), Geotrichum candidum (1,93%), Mucor racemosus (4,32%), and Penicillium chrysogenum (14,11%). Chemical cellulose structure and fungi species influence the difference percentage of crude protein and crude fiber. Chemical cellulose structure which amorf shape was more easy to degrade better than crystal shape. Fungi species have difference complexity enzymes (cellulose, hemicellulose, ligninase) and optimum growth level. High oil that can blocked the optimum growth of fungi and raising temperature matter that have involved in aeration and water activity alteration were another influence factor that have made difference percentage of crude protein and crude fiber.

Abstrak :
Aktivitas biologi, toksisitas, disposisi dan metabolisme obat sangat berbeda untuk masing-masing enansiomer obat khiral. Banyak senyawa khiral yang aktivitas biologinya semata-mata terletak pada salah satu enansiomer, sedangkan enansiomer pasangannya bersifat kurang potensial untuk pengobatan, tidak aktif, bersifat toksik atau bahkan bereaksi berlawanan dengan efek yang diinginkan. Penelitian ini bertujuan melakukan isolasi dan karakterisasi lipase R stolonifer UICC 137 serta aplikasinya sebagai biokatalis untuk hidrolisis (R,S)-ibuprofen metil ester. Lipase diisolasi dari enzim kasar dengan metode pengendapan bertahap menggunakan amonium sulfat. Aktivitas lipolitik lipase ditentukan terhadap substrat minyak zaitun dengan metode titrimetrik. Resolusi (R,S)-ibuprofen metil ester dengan biokatalis lipase dilakukan dengan metode hidrolisis di dalam buffer pH 7,0 dan temperatur 40-42°C. Sebagai pembanding, dilakukan resolusi (R,S)-ibuprofen metil ester dengan biokatalis lipase Candida rugosa (Sigma). Analisis produk resolusi dilakukan dengan spektrofotometer IR, polarimeter dan Kromatografi Cair Kinerja Tinggi (KCKT) yang dilengkapi dengan kolom khiral Cyclobond I 2000. Kondisi optimum untuk penentuan aktivitas lipolitik adalah pH 7-7,5 dan temperatur 370 C. Enzim kasar R. stolonifer UICC 137 mempunyai aktivitas spesifik 20,20 Unit/ mg protein, nilai Vmaks = 15,15 µmol/menit dan KM = 12,5 mg/ ml. Enzim kasar dapat mempertahankan aktivitas lipolitiknya sebesar 79,90 %, 68,04 % dan 52,62 % setelah diinkubasi selama 90 menit pada temperatur 40, 50 dan 600 C. Diantara 4 fraksi lipase yang diperoleh, lipase fraksi 30 - 60 % mempunyai aktivitas spesifik yang lebih tinggi yaitu 47,70 -Unit/mg protein. Resolusi (R,S)-ibuprofen metil ester dengan biokatalis lipase fraksi 30 - 60 % menghasilkan produk ibuprofen (43,1456 %) dengan kelebihan enansiomer-S (enantiomeric excess = ees) = 19,334 %.

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Isolation and Characterization of Rhizopus stolonifer UICC 137 Lipase and Its Application for Resolution of (R,S)-Ibuprofen Methyl Ester The biological activity, toxicity, drug disposition and metabolism can be dramatically different for the enantiomers of a chiral drug. There are numerous chiral compounds in which the desired biological activity solely resides in one enantiomer of chiral drug, with the other isomers being less potent, inactive, toxic, or even acting with cross-purpose effect. The aim of this study was to isolate and characterize the crude lipase of Rhizopus stolonifer UICC 137. Characterization of lipase was focused on the specific ability of lipase to hydrolyze (R,S)-ibuprofen methyl ester. The lipase was isolated from the crude enzyme by ammonium sulfate precipitation method. The lipolitic activity was determined by titrimetric method toward olive oil - arabic gum emulsion as a substrat. The lipase-catalyzed resolution of (R,S)-ibuprofen methyl ester were carried out at 40-42° C in phosphate buffer pH 7,0. The resolution products were analyzed by IR Spectrophotometer, polarimeter and HPLC system equipped with a chiral column of CyclobondI 2000. A resolution of (R,S)-ibuprofen methyl ester using C rugosa lipase (Sigma), was used as a reference. The optimum condition for lipolitic activity measurement were pH of 7,5 and temperature of 37° C. The crude enzyme has a specific activity of 20,20 Unit/ mg protein, the Vmax was 15,15 µmol/min and Km was 12,5 mg/ ml. The crude enzyme retained 79,90 %, 68,04 % and 52,62 % of its lipolytic activity, when incubated for 90 minutes at temperature of 40, 50 and 60 ° C respectively. Among four lipase fraction, the 30 - 60 % lipase fraction has a higher specific activity of 47,70 Unit/ mg protein. The resolution of (R,S)-ibuprofen methyl ester by the 30 - 60 % lipase fraction produced an enantioenriched S(+)-ibuprofen with an enantiomeric excess of 19,334 %.

Abstrak :
Ruminants are herbivorous mammals that have special digestive tract, rumen, where digestion of cellulose and polysaccharides can be carried out by rumen microorganisms. Methanogenic bacteria in the rumen using H2 compounds results from anaerobic fermentation of carbohydrates to form methane. Methane production in the rumen is an energetically wasteful process, since the feed intake will be converted to methane and eructated as gas (Bunthoen, 2007). Rumen protozoa have a potential role in the process of digestion and breakdown of organic material. Hydrogen (H2) as one of the protozoa fermentation products are used by methanogenic bacteria to form methane. This causing methanogenic bacteria often found living attached to the surface of protozoa to keep a constant supply of hydrogen. The purpose of this study is to enumerate the number of methanogenic bacteria and protozoa with different diet and after the addition of probiotic Lactobacillus plantarum TSD-10 in vitro. This report consist of two parts, which are (1) Effect of Feeding Composition on Total Methanogenic Bacteria and Protozoa Rumen, and (2) Influence of Probiotic Lactobacillus plantarum TSD-10 on Total Methanogenic Bacteria and Protozoa In Vitro. The research was conducted at the Laboratory of Industrial Microbiology, Research Centre of Biotechnology? Indonesian Institute of Sciences (LIPI), Cibinong Bogor, from September 2008 ? May 2009. The treatment are diet A with ratio of grass : concentrate (30 : 70) and diet B with ratio of grass : concentrate (70 : 30). The probiotic L. plantarum TSD-10 dose are 0%, 5%, 10% and 15% v/v. The number of methanogenic bacteria obtained from diet A ranges between (0,74 ? 0,89) x 107 cfu/ml, whereas in diet B ranged from (1,71 ? 2,58) x 107 cfu/ml. Methanogenic bacteria average on feed B ((2,19 ± 0,44) x 107 cfu/ml) higher than the feed A ((0,82 ± 0,07) x 107 cfu/ml). Based on the Analysis of Variance (ANOVA), different composition of diet A and B, significantly affect the number of methanogenic bacteria ( 5%), with the best diet composition in suppressing the growth of methanogenic bacteria is diet A. The number of methanogenic bacteria in diet B are higher since the value of a more alkaline pH (8). According to Mirzaei-Aghsaghali et al. (2008), methanogenic bacteria are sensitive to changes in pH. Decrease in pH value will decrease the number of methanogenic bacteria and cause less methane gas produced. The low number of methanogenic bacteria on diet A, can also be caused by the ratio of acetate : propionate obtained lower than in diet B, and it also causes a lower pH of the diet A (Lana et al., 1998). The ANOVA showed the methanogenic bacteria average between diet A and B in the morning and afternoon sampling significantly different between treatments ( 5%), with the best treatment in suppressing methanogenic bacteria from each sampling were diet A. Increased methanogenic bacteria after feeding may be associated with the presence of protozoa in the rumen cilliata that serves as a producer of hydrogen and bacterial attachment to methanogen. Composition diet B low in fiber and high in starch are preferred by the protozoan (Leedle and Greening, 1988). The number of protozoa obtained from the diet A ranges between (1,93 ? 3,95) x 105 cells/ml, whereas the diet B ranged from (2,81 ? 4,35) x 105 cells/ ml. Protozoa average on diet B ((3,76 ± 0,83) x 105 cells/ml) higher than the diet A ((3,08 ± 1,04) x 105 cells/ml). Based on the ANOVA, differences composition diet A and B, not significantly different between treatments (5%). Diet B with a higher pH value causes no influential ration of protozoa, which does not cause a decrease in the number of protozoa. The ANOVA indicate that the average range of protozoa between diet A and B are significantly different (5%) in the morning sampling, with the best treatment in suppressing the number of protozoa are diet A. The afternoon sampling, ANOVA showed that the treatment was not significantly different (5%). Protozoa observed in treatment diet A and B are families of, Ophryoscolecidae, Isotrichidae and Blepharocorythidae. Most number obtained from each diet is Ophryoscolecidae, while the less is Blepharocorythidae. This is due to Ophryoscolecidae a part of the Order Entodiniomorphida who compiled most of rumen cilliata. In the contrary, Family Isotrichidae and Blepharocorythidae are part of the order Trichostomatida which is rarely found in rumen (Ogimoto and Imai, 1981). Decreasing in the number of methanogenic bacteria in the diet B (56,8%) higher than diet A (29,8%), while the decrease in the number of protozoa in the diet B (64,9%) higher than diet A (62,7% ). Diet B with a higher concentrate composition can provide a change in the pattern of rumen fermentation. These changes make the environment less suitable for methanogenic bacterial growth. One of the unfavorable change is a reduction of rumen pH values (Moss et al., 2000). On the addition of probiotics in vitro, the ANOVA showed the range of the number of methanogenic bacteria was not significantly different ( 5%) on the variations of diet A and B but significantly different (5%) on the number of protozoa, with the best in suppressing the growth of protozoa are diet A. Variations doses of probiotic significantly different (5%) on the number of methanogenic bacteria and protozoa, with the best dose 5% v/v to suppress methanogenic bacteria and 15% v/v to suppress protozoa in vitro. Feed Digestibility Coefficient (FDC) shows the FDC from 27,99 ? 31,95%, while the diet B ranged from 25,85 to 31,3%. In diet A, the value FDC obtained tended to increase (8,5%) along with increasing concentration of probiotic L. plantarum TSD-10. Increasing FDC value expected to suppress the growth of methanogenic bacteria by altering the rumen fermentation pattern which results in volatile fatty acids produced. Diet A shows the value of higher acetate than propionate, because diet A high on fiber that will support the growth of the acetate-producing bacteria species, diet B rich in starch that supports the growth of propionic-producing bacteria species, and marked by increasing propionate than acetate (France and Dijkstra, 2005).

Abstrak :
Peneliti terdahulu telah melakukan penelitian biotransformasi progesteron menjadi 1 la-hidroksiprogesteron menggunakan kapang lokal R.stolonifer UICC 137. Namun rendemen hasil biotransformasi tersebut masih rendah. Penelitian ini bertujuan mengembangkan galur R.stolonifer UICC 137 dan R.stolonifer UICC 137/n1 dengan mutasi kimia etil metan sulfonat (EMS). Mutan yang diperoleh diharapkan dapat mentransformasi progesteron menjadi l1a-hidroksiprogesteron lebih tinggi dari galur inang. Untuk mendapatkan mutan yang baik mutagenesis dilakukan menjadi dua tahap. Pada mutagenesis pertama diberikan variasi dosis EMS dan variasi waktu inkubasi. Seleksi mutan dilakukan secara acak, kemudian isolat yang memberikan % sintas yang terkecil dan memberikan % biotransformasi terbesar, dipilih sebagai mutan. Mutagenesis kedua dilakukan terhadap mutan-mutan dengan menggunakan dosis EMS yang memberikan % sintas terkecil (dari mutagenesis pertama). Uji stabilitas dilakukan terhadap mutan-mutan setelah dilakukan optimasi proses biotransformasi. Seleksi mutagenesis pertama untuk R.stolonifer U1CC 137/t dan R.stolonifer UICC 137/nit masing-masing menghasilkan 50 koloni kapang. Dari hasil isolasi, Gt20 dan Gn1t34 memberikan rendemen paling tinggi dan dipilih sebagai mutan. Mutagenesis kedua dilakukan. terhadap 6 mutan R.stolonifer UICC 1371t dan 5 mutan R.stolonifer UICC 137/nit (dari mutagenesis pertama), Gt40 dan Gn1t64 memberikan rendemen yang paling tinggi dan dipibh sebagai mutan. Konsentrasi awal substrat (progesteron) pada biotransformasi optimum mutan-mutan tersebut adalah 0,8 glLiter, laju pengadukan 150 rpm (Gt20 & Gt40), dan 125 rpm (Gn1t34 & Gn1t64). Mutan Gt40 memberikan yield yang tertinggi yaitu 46,15% ( 222,1% nisbah terhadap kontrol). Penyimpanan dalam ruangan dingin (2 °C-3 °C, selama 25 hari setiap generasi), mutan-mutan tersebut diatas stabil sampai generasi keempat. Dalam inkubator (30°C, selama 10 hari setiap generasi) mutan (3t20 dan Gt40 stabil sampai generasikeempat, tetapi Gnlt34 dan Gnlt64 mulai stabil pada generasi kedua sampai generasi kelima. Mutagenesis of Rhizopus stolonifer UICC 137 and Rhizopus stolonifer UICC 137/n1 by Ethyl Methane Sulphonate to Increase the Biotransformation Production of Progesterone to l lα-hydroxyprogesteroneThe previous researcher has reported that Rhizopus stolonifer 'ACC 137 can be used to transform progesterone to 11α-hydroxyprogesterone but with a low product yield. The aim of this study is to improve strains of Rhizopus stolonifer UICC 137 & Rhizopus stolonifer UICC 137/n1 using chemical mutation of ethyl methane sulphonate (EMS) technique. The fungal mutants are expected to produce higher progesterone transformation than the parent strains. Two steps of mutagenesis and randomized screening method were utilized to obtain satisfactory mutants. At the first mutagenesis, various EMS doses were given and fungus with the smallest percentage of survival were collected. The mutants were chosen from isolated fungus giving higher biotransformation yield. The second mutagenesis, repeating the first one, was imposed to the mutant from the last selection with the appropriate parameters. The mutants of Gt20, Gt40, Gnlt34 and Gn1t64 gave relatively higher biotransformation yield compared to the parent strains. The highest biotransformation yield obtained was 46.15% by Gt40 mutant (222.1% compared to the control). All selected mutants were stable up to fourth generation when they maintained in cool chamber (2 - 3°C for 25 days each generation). However, in incubator (30°C for 10 days each generation), the Gt20 and Gt40 mutants were stable up to fourth generation but Gnlt34 and Gnlt64 mutants stable from second to fifth generation.

Abstrak :
Beberapa senyawa steroid yang aktif farmakologik mempunyai atom oksigen pada atom karbon posisi sebelas (C-11), misalnya : kortison, kortikosteron, prednison, dan prednisolon. Senyawa-senyawa tersebut dapat diproduksi melalui sintesis parsial (semisintesis) kortisol dari progesteron atau korteksolon. Kesulitan utama pada sintesis kortisol secara kimiawi adalah pemasukkan satu atom oksigen pada posisi C-11 dalam cincin steroid. Kesulitan ini dapat diatasi dengan penggunaan mikroorganisme. Penelitian ini bertujuan untuk mempelajari kemampuan tiga kultur kapang lokal yaitu dua jenis kapang (Rhizopus stolonlfer UICC 137 dan Aspergillus niger) untuk melakukan transformasi progesteron, serta Curvularia lunata untuk melakukan transformasi korteksolon. Percobaan yang dilakukan terhadap R. stolonifer dan A. niger berdasarkan metode transformasi progesteron menjadi 11µ-hidroksiprogesteron, sedangkan terhadap C. lunata berdasarkan metode transforrnasi 11-deoksikortisol menjadi kortisol. Penelitian dilakukan dengan memvariasikan 5 parameter percobaan yaitu ; (1) saat penambahan substrat (pada percobaan dengan C. lunata parameter ini adalah waktu germinasi), (2) waktu inkubasi, (3) pH medium, (4) konsentrasi substrat, dan (5) laju pengadukan. Percobaan dilakukan dengan sistem "batch", di dalam labu-labu Erlenmeyer 100 ml (kecuali percobaan biotransformasi kondisi optimum memakai labu 500 ml) dan diinkubasi dalam bak air penggojog pada suhu 30°C. Biotransformasi optimum oleh Rhizopus stolonrfer berlangsung jika substrat (progesteron) ditambahkan setelah pertumbuhan kapang mencapai pertengahan fasa eksponensial (14 jam setelah inokulasi kapang ke dalam medium). Medium biotransformasi terdiri dari campuran glukosa, ekstrak khamir, beberapa garam mineral, dan unsur runut. Medium dengan tingkat keasaman (pH) awal 5 memberikan transformasi optimum. Kondisi optimum lainnya adalah inkubasi selama 8 jam di dalam medium sambil digojog 100 gojogan/menit dan konsentrasi awal substrat g/liter. Rendemen produk biotransformasi oleh R. stolonifer adalah 49,88% transformasi. Biotransformasi optimum oleh Aspergillus niger mempunyai kondisi optimum penambahan substrat pada saat pertumbuhan kapang mencapai fasa eksponensial (26 jam setelah inokulasi kapang ke dalam medium), konsentrasi awai substrat 0,6 g/l, penggunaan pH awal medium 6, dan inkubasi selama 20 jam sambil digojog 100 gojogan/menit. Produk biotransformasi oleh A. niger memiliki rendemen sebesar 46,03% transformasi. Biotransformasi korteksolon oleh Curvularia lunata mempunyai rendemen produk terlalu kecil (19,31% transformasi). Kondisi optimumnya adalah proses germinasi spora selama 36 jam dan proses biotransformasi memakai substrat 1,5 g/l dalam medium dengan pH awal 6 sambil digojog 120 gojogan/menit selama 50 jam.

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Several pharmacological active steroid compounds have an oxygen atom attached to the 11th carbon atom on steroid ring (C-11), such as : cortisone, corticosterone, prednisone, and prednisolone. These compounds could be produced through a cortisol partial synthesis from progesterone or cortexolone. If cortisol synthesized chemically, it is difficult to introduce an oxygen atom to C-1I in steroid ring but this process could be conducted by using microorganism. The aim of this study is to determine the ability of Rhizopus stolonifer UICC 137 and Aspergillus niger to transform progesterone, and the ability of Culvularia lunata to transform cortexolone. The experiments for Rhizopus stolonifer UICC 137 and Aspergillus niger based on progesterone transformation to 11µ-hydroxyprogesterone and for Culvularia lunata based on cortexolone transformation to cortisol. The biotransformations were varied with five experiment parameter, i.e. : (1) time interval of substrate addition (substrate addition at different growth phase), in C. lunata this parameter is germination time, (2) incubation time, (3) medium acidity (pH), (4) substrate concentration, and (5) stirring rate. Biotransformation process was carried out on batch system in 100 ml Erlenmeyer flasks (for optimum conditions of biotransformation, 500 ml Erlenmeyer flasks were used) then these flasks were incubated in a shaking waterbath with temperature maintained at 30°C. The optimum biotransformation for R. stolonifer was reached when the substrate (progesterone) was added to the middle of the exponential growth phase (14 hours after spores inuculation). Biotransformation medium contained glucose, yeast extract, some mineral salts, and trace elements. The medium with pH 5 gave the optimum transformation. The Optimum transformation were also found after 8 hours incubation at 100 stroke/minute shaking with the initial substrate concentration of 1 gll, The result for R. stolonifer was 49.88% transformation. The optimum biotransformation conditions for A. niger were found as follows : substrate addition to the initial of the exponential growth phase (26 hours after spores inoculation), initial substrate concentration of 0.6 g/l, medium with pH 6, and 100 stroke/minute shaking for 20 hours incubation. The result for A. niger was 46.03% transformation. Cortexolone biotransformation by using Curvularia hrnata gave a very low product yield (19.31% transformation). The optimum conditions for cortexolone biotransformation were found as follows : spores germination for 36 hours, biotransformation process in a liquid medium with the initial pH 6, substrate concentration of 1,5 g/l, and 50 hours incubation time at 120 stroke /minute shaking.

Abstrak :
Penelitian bertujuan mengisolasi dan mengidentifikasi khamir phylloplane Broussonetia papyrifera asal Bandung (Dago Pojok), Garut (Tunggilis dan Sukadanu), dan Trowulan, menguji kemampuan khamir antagonis dari daun B. papyrifera asal Desa Sukadanu dan Desa Tunggilis, Garut, Jawa Barat yang berpotensi sebagai agens biokontrol terhadap kapang-kapang penyebab kebusukan pada buah tomat pascapanen serta mengetahui viabilitas khamir setelah dipreservasi pada suhu -80 oC. Sebanyak 2.543 isolat khamir diperoleh dari empat wilayah sampling menggunakan metode washing dan membrane filter method. Pemilihan 82 isolat khamir representatif berdasarkan kemiripan morfologi koloni. Identifikasi khamir dilakukan berdasarkan sequence pada daerah internal transcribed spacer regions ribosomal DNA. Hasil identifikasi menunjukkan bahwa isolat khamir tersebut terdiri atas 17 genera dan 32 spesies: sebanyak 11 genera termasuk ke dalam Ascomycota (Saccharomycetes dan Dothidiomycetes), dan sebanyak enam genera termasuk Basidiomycota (Tremellomycetes, Microbotryomycetes, dan Ustilaginomycetes). Tiga kapang representatif berdasarkan hasil isolasi dari buah tomat dan uji patogenitas dapat menyebabkan kebusukan pada buah tomat pascapanen, yaitu Alternaria alternata, Lasiodiplodia theobromae, dan Syncephalastrum racemosum. Enam spesies khamir antagonis dapat menghambat pertumbuhan dan sporulasi A. alternata, L. theobromae, dan Syn. racemosum yaitu Candida saopaulonensis UICC Y-492, Candida pseudojiufengensis UICC Y-475, Debaryomyces hansenii UICC Y-488, Geotrichum candidum UICC Y-495, Hyphopichia burtonii UICC Y-496, dan Rhodotorula mucilaginosa UICC Y-476. Khamir antagonis dari B. papyrifera memiliki kemampuan menghambat pertumbuhan kapang A. alternata dan L. theobromae penyebab kebusukan pada buah tomat pada suhu 26--28oC selama 15 hari inkubasi. Khamir C. pseudojiufengensis UICC Y-475 dapat menghambat pertumbuhan kapang dan gejala kebusukan pada buah tomat (100%) disebabkan kapang A. alternata. Khamir C. saopoulenensis UICC Y-492 dan Rh. mucilaginosa UICC Y-513 dapat menghambat pertumbuhan kapang dan gejala kebusukan pada buah tomat (67%) yang disebabkan L. theobromae. Hasil pengujian viabilitas khamir setelah dipreservasi pada suhu -80oC selama 180 hari menunjukkan metode tersebut baik untuk preservasi jangka panjang empat spesies khamir potensial agens biokontrol pada buah tomat, yaitu khamir C. pseudojiutengensis UICC Y-475, C. saopoulenensis UICC Y-492, Hyp. burtonii UICC Y-496, dan Rh. mucilaginosa UICC Y-513. Seluruh strain yang diuji menunjukkan viabilitas yang tinggi (rerata CFU . 1x 108/ml). Jumlah sel khamir antara lain: C. pseudojiutengensis UICC Y-475 (1,08 x 108 CFU/ml), C. saopoulenensis UICC Y-492 (0,65 x 108 CFU/ml), Hyp. burtonii UICC Y-496 (1,76 x 108 CFU/ml), dan Rh. mucilaginosa UICC Y-513 (2,13 x 108 CFU/ml).

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The study was aimed to isolate and identify phylloplane yeasts from Broussonetia papyrifera plants from Bandung (Dago Pojok), Garut (Tunggilis and Sukadanu), and Trowulan; to investigate the yeasts with antagonistic abilities against moulds which attack post-harvest tomato fruits; and to observe the yeast viability after preservation at a temperature of -80 oC. Two thousand five hundred and forty-three yeast isolates were obtained using the washing method and the membrane filter method. Eighty-two representative yeast isolates were selected based on similarity of colony morphology. Identification was based on sequence data of internal transcribed spacer regions of ribosomal DNA (ITS rDNA). The identification result showed that the 82 representative isolates were consisted of 17 genera and 32 species. Eleven of these genera are belong to Saccharomycetes and one genus belongs Dothidiomycetes (Ascomycota). Six genera are belong to Tremellomycetes, Microbotryomycetes, and Ustilaginomycetes (Basidiomycota). Three representative moulds obtained from the pathogenicity test were able to cause serious damage on post-harvest tomato fruits. These moulds were identified as, i.e. Alternaria alternata, Lasiodiplodia theobromae, and Syncephalastrum racemosum. Six antagonistic yeasts were able to inhibit growth and sporulation of post-harvest tomato moulds, i.e. Candida saopaulonensis UICC Y-492, Candida pseudojiufengensis UICC Y-475, Debaryomyces hansenii UICC Y-488, Geotrichum candidum UICC Y-495, Hyphopichia burtonii UICC Y-496, and Rhodotorula mucilaginosa UICC Y-476. The antagonistic yeasts were tested for their abilities to inhibit growth of A. alternata and L. theobromae which cause fruit rot on post-harvest tomatoes at 26--28oC for 15 days. Candida pseudojiufengensis UICC Y-475 was able to inhibit growth of A. alternata and reduce fruit rot symptoms in tomato fruit (100%). Candida saopoulenensis UICC Y-492 and Rh. mucilaginosa UICC Y-513 were able to inhibit growth of L. theobromae and reduce fruit rot symptoms in tomato fruit (67%). The yeast viability was observed after being preserved at -80oC on day-1 (H1), day-7 (H7), day-14 (H14), day-30 (H-30), and day-180 (H-180). The results showed that all strains do not lose their viability after freezing at -80oC for 180 days. The number of cells for each strain after revival from preservation after 180 days were counted: C. pseudojiufengensis UICC Y-475 (1,08 x 108 CFU/ml), C. saopoulenensis UICC Y-492 (0,65 x 108 CFU/ml), Hyp. burtonii UICC Y-496 (1,76x 108 CFU/ml), and Rh. mucilaginosa UICC Y-513 (2,13 x 108 CFU/ml).