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"ABSTRACTBiological control of postharvest diseases of fruits and vegetables byantagonistic microorganism seems increasingly promising to replace the use of synthetic fungicides which are subjected to some limitation due to development of fungicides-resistant strain of the pathogens and risk for consumers and the environment (Lima et al, 1999). Several species of yeast have been reported to reduce postharvest fungal decay on fruits. One of the antagonistic yeast that has been use as commercial biocontrol is Metchnikowia fructicola in Shemerm product (Vero et al., 2002) Yeast Rhodotomla has been studied for the postharvest biologicalcontrol various mould pathogens on various fruit (Castoria et al., 1997).University of Indonesia Culture Collection (UICC) have Rhodotorula spp.strains from plants of Cibodas Botanical Garden, and moulds frompostharvest decayed-tomatoes and plants. The ability of these yeast strains as biocontrol agents against has not been reported.This thesis consists of two parts. Part 1 is entitled The antagonisticActivity of Rhodotorula spp. from Cibodas Botanical Garden Against Tomato Plant Infected-Causing Moulds. Part 2 is entitled The Potential of Rhodotorula sp. UICC Y-381 as Biocontrol Agent of Aspergillus ochraoeus on Postharvest Tomatoes. The objectives of this research are to obtain a potential Rhodotorula sp. with antagonistic activity against tomato infected-causing moulds, and to obtain infoimation on the ability of Rhodotorula sp. UICC Y- 381 as a biocontrol agent in reducing the severity of decay by Aspergillus ochraceus. The research was carried out in Laboratory of Microbiology, Department of Biology, and Center of Excellence Indigenous Biological Resources-Genome Studies (CoE IBR-GS), Faculty of Mathematics and Natural Sciences, from July 2008-July 2009.Yeast Malt Agar (YMA) was used for yeast growth medium, and PotatoDextrose Agar (PDA) was used for maintenance of fungi. The media PDA and Potato Dextrose Agar (PDB) were used for antagonistic test.Six strains of Rhodotorula spp. (Rhodotorula sp. UICC Y-318,Rhodotorula sp. UICC Y-325, Rhodotorula sp. UICC Y-332, Rhodotorula sp. UICC Y-381, Rhodotomla sp. UICC Y-384, and Rhodotorula sp. UICC Y-386) were investigated as antagonistic yeasts against Aspergillus ochraceus D1.2.2.SSM3, A. terreus D2.2.MC, and Drechslera sp. D1.3.MC. The yeasts were obtained from plants of Cibodas Botanical Garden, and the moulds were obtained from decayed tomatoes and infected plants, belonging to the University of Indonesia Culture Collection (UICC). Antagonistic test by strip method was carried out by usingconcentration of yeast cells at (1 .2-5.2) x 10° CFU/ml, and A. ochraceusD1.2.2.SSM3 at 4.7 x 10? CFU/ml, A. terreus D2.2.Mc at 3.2 x 10° CFU/ml,and Drechslera sp. D1.3.MC at 5.2 x 10? CFU/ml. Inoculation of the yeastcells on PDA was carried out 4 hours earlier before inoculation of mouldspores on petri dishes. Results showed that highest percentage reduction of mould colonies was shown by Rhodotorula sp. UICC Y- 325 againstDrechslera sp. (28.12%-72.14%), followed by Rhodotorufa sp. UlCC Y-381 against A. ochraoeus (54.28%-72.46%), and Rhodotoruta sp. Y-318 against A. terreus (21.76% - 58.10%) during 6-day incubation.Antagonistic test by co-culture method was carried out by usingconcentration of yeast cells at (1 .58-5.59) x 10° CFU/ml, and Aspergillus ochraceus D1.2.2.SSM3 at 7 x 10? cFU/ml, A. terreus D2.2.MC at 1.5 x 10? CFU/ml. Inoculation of the yeast cells on PDB was carried out 8 hours earlier before inoculation of mould spores on broth medium. Results showed that highest percentage reduction of conidial heads and hyphal width was shown by Rhodotorula sp. UICC Y-381 against A. ochraceus (9.45% and 12.43%; 7.10% and 7.51 %, after 2- and 3-day incubation, respectively). Rhodotorula sp. UICC Y-332 reduced conidial heads of A. terreus (10.17% and 9.60% after 2- and 3-day incubation) but, was not able to reduce hyphal width of A. terreus. Microscopic observation by slide culture method on PDA showed that there was attachment of Rhodotorula spp. cells to the hyphae of Drechslera sp., however, Rhodotorula spp. UICC Y-386 attached more intensively and colonized the hyphae.The ability of Rhodotorula sp. UICC Y-381, which was isolated fromplant leaves, as a biocontrol agent against postharvest tomato fruit decay- causing mould Aspergillus ochraceus D1 .2.2.SSM3 was evaluated. Observation was carried out for 15 days at 25°C - 27°C. Results showed that Rhodotorula sp. UICC Y-381 was able to reduce the severity of decay by A.ochraceus with 100% reduction until day-12, when compared to control. The synthetic fungicide Dithane M-45 at a concentration of 0.08% reduced the severity of decay to 100% until 15-day incubation."

"Cryptococcus (Vuillemin) merupakan salah satu genus khamir yang berpotensi sebagai penghasil β-glukan karena memiliki ekstrapolisakarida (EPS) dengan salah satu komponen adalah glukan. Penelitian bertujuan memperoleh strain Cryptococcus potensial sebagai penghasil EPS yang mengandung β-1,3-glukan yang tinggi. Penelitian dilakukan di Departemen Biologi, Departemen Farmasi dan Departemen Kimia, FMIPA UI, Depok selama 10 bulan (Juni 2006--Maret 2007). Penapisan pada 36 strain Cryptococcus berdasarkan intensitas warna biru yang terbentuk antara kompleks aniline blue dan β-1,3-glukan. Hasil penapisan menunjukkan bahwa seluruh strain Cryptococcus positif mengandung β-1,3-glukan pada dinding sel dan EPS dengan intensitas warna biru yang bervariasi (skor 1--3 dari biru muda sampai biru tua). Skor tiga ditunjukkan oleh tiga strain, yaitu Cryptococcus laurentii UICC Y-232, Cryptococcus sp. UICC Y-179 dan Cryptococcus heveanensis UICC Y-230 yang menunjukkan bahwa ketiga strain paling potensial dalam menghasilkan β-1,3-glukan pada dinding sel dan EPS. EPS dari dua strain paling potensial diisolasi dan dimurnikan, serta dianalisis dengan HPLC. Cryptococcus laurentii UICC Y-232 menghasilkan EPS sebanyak 0,8 g/g berat kering (80%) sedangkan Cryptococcus sp. UICC Y-179 sebanyak 0,77 g/g berat kering (77%). Berdasarkan hasil analisis HPLC, EPS dari C. laurentii UICC Y-232 dan Cryptococcus sp. UICC Y-179 kemungkinan merupakan β-glukan."

"Microbial communities usually have mixed populations, only in uniqueenvironmental situations do microorganisms live entirely alone. Thus many types of interactions are possible among the members of an ecosystem?s community. In general, the constant association of different organisms in an ecosystem is referred to as symbiosis, with the associates being called symbionts. One type of a symbiosis is antagonism. Antagonism is a symbiotic relationship in whichone population of microorganisms has a harmful effect on the growth of another microbial population (Batzing 2002: 696). A number of microorganisms (bacteria, yeasts, fungi) which effectivelycontrol postharvest pathogens have been identified as antagonists (Mari and Guizzardi 1998:60). A variety of microbial antagonists were reported to control several different pathogens on various fruits. The organism that suppresses the pest or pathogen is referred to as the biological control agent (BCA) (Pal & Mcspadden Gardener 2006: 1). Biological control may in simple terms be defined as the use of one living organism to control another (Druvefors 2004: 4).Often antagonists are isolated on the surface of plants; this natural presence makes them more likely to succeed because of their colonization ability and environmental adaptation (Mari and Guizzardi 1998:60). The use of yeasts as antagonists appears to be quite promising, although the mechanism has not yet been fully elucidated. Some antagonist yeasts have been reported as biocontrol agent of fungal pathogen on fruits. Zhao et al. (2008: 115--116) reported that tomato fruit treated with Pichia guillermondii had an infection rate of 25% which was caused by Rhizopus nigricans, which wassignificantly lower than the control (41.67%). Kalogiannis et al. (2006: 72) reported that Rhodotorula glutinis Y-44 significantly reduced disease incidence caused by Botrytis cinerea on tomato by 52%, compared to the untreated control. Zhang et al. (2004: 84) reported that the application of Cryptococcus laurentii resulted in low average decay incidence caused by B. cinerea in fruit by 7.1%, compared with 40% in the water-treated control fruit. University of Indonesia Culture Collection (UICC) collected epiphytic yeasts from plant samples of Cibodas Botanical Garden, and moulds from decayed tomatoes and infected plants. The ability of the epiphytic yeasts as biocontrol agents against tomato spoilage-causing moulds has not beenreported. This study consists of two parts. Part 1 is The Antagonistic Ability of Epiphytic Yeasts of Cibodas Botanical Garden on Tomato Plant Infected-Causing Moulds. Part 2 is The Potential of Candida sp. UICC Y-328 as a Biocontrol Agent of Aspergillus ochraceus on Postharvest Tomatoes.The purposes of this study were to investigate the ability of six species of epiphytic yeasts in inhibiting the growth of tomato plant infected-causing moulds, and the potential of Candida sp. UICC Y-328 as a biocontrol agent in reducing postharvest tomato spoilage caused by Asp. ochraceus. The media used for growing the yeasts was Yeast Malt Agar (YMA), and maintenance for fungi was Potato Dextose Agar (PDA). The media used for antagonistic test were PDA and Potato Dextrose Broth (PDB). Antagonistic test by strip method was carried out by using the concentrations of yeast cells at (0.7--4.45) x 108 CFU/ml, and Asp. ochraceus at (7.0--8.1) x 107 CFU/ml, Asp. terreus Thom at (7.7--8.6) x 107 CFU/ml andDrechslera sp. at (0.45--3.5) x 105 CFU/ml. The yeast cells were inoculated 4 hours earlier before inoculation of mould spores on PDA in Petri dishes. Results showed that Candida sp. UICC Y-328 has highest percentage of colony reduction of Asp. ochraceus (56.45%), followed by Metschnikowia reukaufii UICC Y-351 on reducing colonies of Asp. terreus and Drechslera sp. (25.42% and 51.28%, respectively) during 6-day incubation. Antagonistic test by co-culture method was carried out by using the concentrations of yeast cells at (0.7--4.45) x 108 CFU/ml, and Asp. ochraceus at (6.0--8.6) x 107 CFU/ml, Asp. terreus at (4.6--9.5) x 107 CFU/ml. The yeast cells were inoculated 8 hours earlier before inoculation of mould spores on PDB. Results showed that Candida sp. UICC Y-328 reduced the size of conidial heads(5.52%) and hyphae (8.29%) of Asp. ochraceus, at 3-day incubation.Cryptococcus laurentii UICC Y-379 reduced the size of conidial heads and hyphae of Asp. ochraceus (15.07% and 11.60% respectively) and Asp.terreus (12.35% and 24.47% respectively) at 3-day incubation. Antagonistic test by slide culture method showed that the yeast cells of four strains (Candida rancensis UICC Y-326, Cr. laurentii UICC Y-319, Cr. laurentii UICC Y-379,and M. reukaufii UICC Y-351) attached to hyphae of Drechslera sp. after 3- and 4-day incubation.Cells of Candida sp. UICC Y-328 attached to hyphae of Drechslera sp. after 4-day incubation. Cells of Cr. laurentii UICC Y-385 was not able to attach to hyphae of Drechslera sp. Candida sp. UICC Y-328 was potential in reducing the growth of Asp. ochraceus, and was investigated further for its potential as a biocontrol agent. Wounds on postharvest tomatoes were inoculated with 25 µl of yeast cellsuspension and 25 µl of mould spore suspension. The yeast cells wereinoculated 24 hours earlier before inoculation of mould spores on wounds of tomatoes. Biocontrol study showed that incidence of spoilage in postharvest tomatoes which were wounded and inoculated with Candida sp. UICC Y-328 and Asp. ochraceus, were reduced by 20% after 15-day incubation at room temperature. All postharvest tomatoes which were wounded and inoculated with Asp. ochraceus as control, were spoiled (100%). Synthetic fungicide Dithane M-45 at a concentration of 0.08% reduced spoilage incidence by 70%. Candida sp.UICC Y-328 was not effective as biofungicide in reducing spoilage incidence."

"Likopen adalah pigmen merah yang terdapat pada tumbuhan dan merupakan senyawa karotenoid yang berfungsi sebagai antioksidan. Senyawa ini merupakan senyawa yang tidak stabil, sehingga untuk mendapatkan senyawa murni dibutuhkan proses yang sulit.Tujuan dari penelitian ini adalah mendapatkan metode isolasi dan purifikasi optimum untuk memperoleh likopen yang murni melalui reaksi saponifikasi. Oleoresin yang berasal dari tomat atau semangka dilarutkan dalam n-propanol selama setengah jam, lalu ditambahkan larutan KOH 45% dan aquadest dengan penimbangan masing-masing komponen tersebut adalah 657,20 mg oleoresin, 16 ml n-propanol, 2,25 ml larutan KOH 45% , dan 3 ml aquadest. Selain n-propanol, pada isolasi ini juga digunakan pelarut etanol dan propilen glikol dengan menggunakan tiga temperatur yang berbeda, yaitu 50°C, 65°C, dan 70°C. Proses isolasi ini berlangsung selama 3 jam, setelah pendinginan selama ± 4 jam presipitat yang terbentuk disaring dengan menggunakan filter glass. Dari ketiga pelarut yang digunakan, n- propanol dengan temperatur 50°C yang memberikan hasil isolasi paling optimum, dengan kadar perolehan kembali likopen yang berasal dari oleoresin tomat dan semangka masing-masing 21,83% dan 18,14%.

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Lycopene is the red pigment was found in plants and carotenoid compound with antioxidant function. This compound is unstable, hence require difficult process to obtain its pure form.The purpose of this study is to determine optimal method of isolation and purification to obtain pure lycopene was through saponification reaction. Oleoresin from tomatoes or watermelon dissolved in npropanol for half an hour, then added by 45% (w/v) KOH solution and aquadest with a ratio of each component: 657.20 mg oleoresin, 16 ml n-propanol, 2.25 ml 45% KOH and 3 ml aquadest. Ethanol and propylene glycol were also used as solvents substituted for n-propanol. The reaction were carried out at three different temperature such as 50°C, 65°C, and 70°C respectively. This isolation were processed for 3 hours, and followed by cooling for 4 hours ± to form precipitate. The precipitate was filtered using a filter glass. From three kinds of solvents used, n-propanol with a temperature of 50°C gives the most optimum isolation result. The recovered lycopene from oleoresin tomato and watermelon were 21.83% and 18.14% of oleoresin respectively."

"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)."