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"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."

"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."

"ABSTRAKTempe selain memiliki nilai nutrisi yang tinggi ternyata juga mengandung senyawa antimikroba. Penelitian ini bertujuan untuk meneliti aktivitas antimikroba dari Rhizopus arrhizus UICC 6 dan Rh. ollgosporus UICC 116 yang ditumbuhkan pada medium ekstrak kedelam dan juga medium Kobayasi yang digunakan sebagal medium pembanding. Fermentasi berlangsung selama 10 dan 14 han, pada suhu 30°C dengan metode still culture. Uji aktivitas antimikroba dilakukan dengan metode difusi agar, terhadap bakteri teruji. Bacillus subtilis UICC B 10, Escherichia co/i UICC B 14, dan Pseudomonas aeruginosa UICC B 22. Has1 penelitian menunjukkan bahwa kedua kapang uji yang ditumbuhkan dalam medium Kobayasi memiliki aktivitas antimikroba yang Iebih balk dibandingkan dengan aktivitas antimikroba dalam medium ekstrak kedelal. Senyawa antimikroba kedua kapang uji yang ditumbuhkan dalam medium Kobayasi menunjukkan aktivitas yang tinggi pada hari ke 10 dan menurun pada hari ke 14. Sebaliknya, pada medium ekstrak kedelal aktivitas antimikroba yang tinggi justru diperoleh pada hari ke 14 fermentasi. Hasil penehtian juga menunjukkan bahwa senyawa antimikroba dan Rh. arrhizus UICC 6 aktif terhadap bakteni teruji Gram negatif. Sedangkan senyawa antimikroba dari Rh. oligosporus UICC 116 aktif terhadap bakteni teruji Gram positif pada hari ke 14."

"Aspergillus flavus UICC 360 telah diketahui dapat menghasilkan senyawa anti-Candida albicans. Penelitian bertujuan untuk mengetahui pengaruh konsentrasi natrium nitrat terhadap kemampuan anti-C. albicans dari Aspergillus flavus UICC 360. Sebanyak (2,8--3,7) x 107 CFU/ml inokulum Aspergillus flavus UICC 360 dengan konsentrasi 1,96% (v/v), diinokulasikan ke dalam medium Czapek?s Dox Broth yang berisi variasi konsentrasi natrium nitrat (0 mM, 23 mM, 29 mM, 35 mM, 41 mM, dan 47 mM). Fermentasi dilakukan selama 7 hari pada suhu ruang (27--30° C). Pengujian kemampuan anti-C. albicans dilakukan dengan menggunakan metode difusi agar cara cakram. Kemampuan anti-C. albicans ditunjukkan oleh terbentuknya zona hambat. Uji perbandingan berganda Least Significancy Difference (LSD) (P < 0,05) memperlihatkan adanya pengaruh nyata pemberian variasi konsentrasi natrium nitrat terhadap ukuran diameter zona hambat.Hasil penelitian menunjukkan NaNO3 29 mM (ekstrak E3 dalam etil asetat) merupakan konsentrasi terbaik untuk aktivitas anti-C. albicans, ditandai dengan diameter zona hambat, yaitu 8,70 ± 0,53 mm (setara dengan nistatin pada konsentrasi 1.581,8 ppm).

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Aspergillus flavus UICC 360 has been known to produce anti-Candida albicans compound. The research aims to determine the effect of sodium nitrate concentration on Aspergillus flavus UICC 360 in producing anti-C. albicans. Inoculum of (2.8--3.7) x 107 CFU/ml of Aspergillus flavus UICC 360 in 1.96% (v/v) concentration was inoculated into Czapek's Dox Broth medium containing various sodium nitrate concentration (0 mM, 23 mM, 29 mM, 35 mM, 41 mM, and 47 mM).

The fermentation was carried out for 7 days at 27--30° C. Investigation of anti-C. albicans test was carried out by disc agar diffusion method. Anti-C. albicans from Aspergillus flavus UICC 360 was shown by the formation of inhibitory zones. Least Significancy Difference test (P < 0.05) showed significant effect of the varying sodium nitrate concentration on inhibitory zone diameter.

The result showed that highest anti-C. albicans was shown by highest inhibition zone diameter at 8.70 ± 0.53 (equivalent to the activity of nystatin at concentration of 1,581.8 ppm) which was achieved at 29 mM NaNO3 (extract of E3 in ethyl acetate)."

"[Aspergillus flavus UICC 360 merupakan fungi yang mampu menghasilkan senyawa metabolit sekunder berupa lovastatin. Penelitian bertujuan untuk mengetahui pengaruh variasi konsentrasi urea terhadap kemampuan Aspergillus flavus UICC 360 dalam menghasilkan lovastatin. Proses fermentasi menggunakan konsentrasi inokulum Aspergillus flavus UICC 360 sebesar 1,96% (v/v) dalam medium Czapek?s Dox Broth (CDB) modifikasi dengan variasi konsentrasi urea (0mM, 33 mM, 42 mM, 50 mM, 58 mM, dan 67 mM) dan inkubasi selama 7 hari pada suhu ruang (27--300C) dengan kecepatan agitasi 90 rpm. Ekstrak hasil fermentasi dalam etil asetat diuji terhadap Candida albicans UICC Y-29 menggunakan metode difusi agar cara cakram. Ekstrak hasil fermentasi dari konsentrasi urea 42 mM mempunyai indeks penghambatan rata-rata tertinggi sebesar 0,54 ± 0,15. Hasil Kromatografi Lapis Tipis (KLT) menunjukkan bahwa nilai Rf ekstrak hasil fermentasi dari konsentrasi urea 42 mM sama dengan lovastatin standar, yaitu 0,42 yang mengindikasikan ekstrak mengandunglovastatin. Uji Least Significant Difference (LSD) (P < 0,05) menunjukkanterdapat perbedaan nyata variasi konsentrasi urea terhadap kemampuan Aspergillus flavus UICC 360 dalam menghasilkan lovastatin. Hal tersebut menunjukkan bahwa pemberian variasi konsentrasi urea berpengaruh terhadap kemampuan Aspergillus flavus UICC 360 dalam menghasilkan lovastatin.;Aspergillus flavus UICC 360 is capable of producing secondary metabolites such as lovastatin. The study aims to determine the effect of variations of urea concentration on the ability of Aspergillus flavus UICC 360 to produce lovastatin. The fermentation process using 1.96% (v/v) inoculum concentration of Aspergillus flavus UICC 360 in the Czapek?s Dox Broth (CDB) medium modified with urea concentration variations (0 mM, 33 mM, 42 mM, 50 mM, 58 mM, and 67 mM) and incubated for 7 days at room temperature (27--30 °C) with agitation speed of 90 rpm. Ethyl acetate extracts were tested against Candidaalbicans UICC Y-29 using agar disc diffusion method. The extractfrom fermentation medium of 42 mM urea has the highest average of inhibition index of 0.54 ± 0.15. Results of Thin Layer Chromatography (TLC) showed that the extract from fermentation medium of 42 mM urea has the same Rf value with lovastatin standard Rf 0.42 which indicated that the extract contained lovastatin. Least Significant Difference (LSD) test showed that there were significant difference in the urea concentration variation in the ability of Aspergillus flavus UICC 360 to produce lovastatin. It shows that variation of urea concentrations affect the ability of Aspergillus flavus UICC 360 to produce lovastatin., Aspergillus flavus UICC 360 is capable of producing secondary metabolites such as lovastatin. The study aims to determine the effect of variations of urea concentration on the ability of Aspergillus flavus UICC 360 to produce lovastatin. The fermentation process using 1.96% (v/v) inoculum concentration of Aspergillus flavus UICC 360 in the Czapek’s Dox Broth (CDB) medium modified with urea concentration variations (0 mM, 33 mM, 42 mM, 50 mM, 58 mM, and 67 mM) and incubated for 7 days at room temperature (27--30 °C) with agitation speed of 90 rpm. Ethyl acetate extracts were tested against Candidaalbicans UICC Y-29 using agar disc diffusion method. The extractfrom fermentation medium of 42 mM urea has the highest average of inhibition index of 0.54 ± 0.15. Results of Thin Layer Chromatography (TLC) showed that the extract from fermentation medium of 42 mM urea has the same Rf value with lovastatin standard Rf 0.42 which indicated that the extract contained lovastatin. Least Significant Difference (LSD) test showed that there were significant difference in the urea concentration variation in the ability of Aspergillus flavus UICC 360 to produce lovastatin. It shows that variation of urea concentrations affect the ability of Aspergillus flavus UICC 360 to produce lovastatin.]"

"[ABSTRAKAspergillus flavus UICC 360 merupakan fungi yang mampu menghasilkan senyawa metabolit sekunder berupa lovastatin. Penelitian bertujuan untuk mengetahui pengaruh variasi konsentrasi urea terhadap kemampuan Aspergillus flavus UICC 360 dalam menghasilkan lovastatin. Proses fermentasi menggunakan konsentrasi inokulum Aspergillus flavus UICC 360 sebesar 1,96% (v/v) dalam medium Czapek’s Dox Broth (CDB) modifikasi dengan variasi konsentrasi urea (0 mM, 33 mM, 42 mM, 50 mM, 58 mM, dan 67 mM) dan inkubasi selama 7 hari pada suhu ruang (27--300C) dengan kecepatan agitasi 90 rpm. Ekstrak hasil fermentasi dalam etil asetat diuji terhadap Candida albicans UICC Y-29 menggunakan metode difusi agar cara cakram. Ekstrak hasil fermentasi dari konsentrasi urea 42 mM mempunyai indeks penghambatan rata-rata tertinggi sebesar 0,54 ± 0,15. Hasil Kromatografi Lapis Tipis (KLT) menunjukkan bahwa nilai Rf ekstrak hasil fermentasi dari konsentrasi urea 42 mM sama dengan lovastatin standar, yaitu 0,42 yang mengindikasikan ekstrak mengandung lovastatin. Uji Least Significant Difference (LSD) (P < 0,05) menunjukkan terdapat perbedaan nyata variasi konsentrasi urea terhadap kemampuan Aspergillus flavus UICC 360 dalam menghasilkan lovastatin. Hal tersebut menunjukkan bahwa pemberian variasi konsentrasi urea berpengaruh terhadap kemampuan Aspergillus flavus UICC 360 dalam menghasilkan lovastatin.

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ABSTRACTAspergillus flavus UICC 360 is capable of producing secondary metabolites such as lovastatin. The study aims to determine the effect of variations of urea concentration on the ability of Aspergillus flavus UICC 360 to produce lovastatin. The fermentation process using 1.96% (v/v) inoculum concentration of Aspergillus flavus UICC 360 in the Czapek’s Dox Broth (CDB) medium modified with urea concentration variations (0 mM, 33 mM, 42 mM, 50 mM, 58 mM, and 67 mM) and incubated for 7 days at room temperature (27--30 °C) with agitation speed of 90 rpm. Ethyl acetate extracts were tested against Candida albicans UICC Y-29 using agar disc diffusion method. The extract from fermentation medium of 42 mM urea has the highest average of inhibition index of 0.54 ± 0.15. Results of Thin Layer Chromatography (TLC) showed that the extract from fermentation medium of 42 mM urea has the same Rf value with lovastatin standard Rf 0.42 which indicated that the extract contained lovastatin. Least Significant Difference (LSD) test showed that there were significant differences in the urea concentration variation in the ability of Aspergillus flavus UICC 360 to produce lovastatin. It shows that variation of urea concentrations affect the ability of Aspergillus flavus UICC 360 to produce lovastatin.;Aspergillus flavus UICC 360 is capable of producing secondary metabolites such as lovastatin. The study aims to determine the effect of variations of urea concentration on the ability of Aspergillus flavus UICC 360 to produce lovastatin. The fermentation process using 1.96% (v/v) inoculum concentration of Aspergillus flavus UICC 360 in the Czapek’s Dox Broth (CDB) medium modified with urea concentration variations (0 mM, 33 mM, 42 mM, 50 mM, 58 mM, and 67 mM) and incubated for 7 days at room temperature (27--30 °C) with agitation speed of 90 rpm. Ethyl acetate extracts were tested against Candida albicans UICC Y-29 using agar disc diffusion method. The extract from fermentation medium of 42 mM urea has the highest average of inhibition index of 0.54 ± 0.15. Results of Thin Layer Chromatography (TLC) showed that the extract from fermentation medium of 42 mM urea has the same Rf value with lovastatin standard Rf 0.42 which indicated that the extract contained lovastatin. Least Significant Difference (LSD) test showed that there were significant differences in the urea concentration variation in the ability of Aspergillus flavus UICC 360 to produce lovastatin. It shows that variation of urea concentrations affect the ability of Aspergillus flavus UICC 360 to produce lovastatin.;Aspergillus flavus UICC 360 is capable of producing secondary metabolites such as lovastatin. The study aims to determine the effect of variations of urea concentration on the ability of Aspergillus flavus UICC 360 to produce lovastatin. The fermentation process using 1.96% (v/v) inoculum concentration of Aspergillus flavus UICC 360 in the Czapek’s Dox Broth (CDB) medium modified with urea concentration variations (0 mM, 33 mM, 42 mM, 50 mM, 58 mM, and 67 mM) and incubated for 7 days at room temperature (27--30 °C) with agitation speed of 90 rpm. Ethyl acetate extracts were tested against Candida albicans UICC Y-29 using agar disc diffusion method. The extract from fermentation medium of 42 mM urea has the highest average of inhibition index of 0.54 ± 0.15. Results of Thin Layer Chromatography (TLC) showed that the extract from fermentation medium of 42 mM urea has the same Rf value with lovastatin standard Rf 0.42 which indicated that the extract contained lovastatin. Least Significant Difference (LSD) test showed that there were significant differences in the urea concentration variation in the ability of Aspergillus flavus UICC 360 to produce lovastatin. It shows that variation of urea concentrations affect the ability of Aspergillus flavus UICC 360 to produce lovastatin., Aspergillus flavus UICC 360 is capable of producing secondary metabolites such as lovastatin. The study aims to determine the effect of variations of urea concentration on the ability of Aspergillus flavus UICC 360 to produce lovastatin. The fermentation process using 1.96% (v/v) inoculum concentration of Aspergillus flavus UICC 360 in the Czapek’s Dox Broth (CDB) medium modified with urea concentration variations (0 mM, 33 mM, 42 mM, 50 mM, 58 mM, and 67 mM) and incubated for 7 days at room temperature (27--30 °C) with agitation speed of 90 rpm. Ethyl acetate extracts were tested against Candida albicans UICC Y-29 using agar disc diffusion method. The extract from fermentation medium of 42 mM urea has the highest average of inhibition index of 0.54 ± 0.15. Results of Thin Layer Chromatography (TLC) showed that the extract from fermentation medium of 42 mM urea has the same Rf value with lovastatin standard Rf 0.42 which indicated that the extract contained lovastatin. Least Significant Difference (LSD) test showed that there were significant differences in the urea concentration variation in the ability of Aspergillus flavus UICC 360 to produce lovastatin. It shows that variation of urea concentrations affect the ability of Aspergillus flavus UICC 360 to produce lovastatin.]"

"Aspergillus flavus UICC 360 has been reported to produce lovastatin. This research was carried out to determine the effect of concentration variation of glucose technical grade on the ability of A. flavus UICC 360 to produce lovastatin. The fermentation process was carried out using inoculum 2% (v/v) modified Czapek's Dox Broth (CDB). Variation of glucose technical grade concentration used were 0 g/L, 5 g/L, 10 g/L, 15 g/L, 20 g/L, 25 g/L, 30 g/L and 35 g/L. Fermentation was carried out for 6 days at room temperature (27--30ºC) with agitation speed of 90 rpm. Extraction of lovastatin was done with ethyl acetate solvent. The extract was assayed by disk diffusion method against Candida albicans UICC Y-29.

The results revealed that the fermentation extract on glucose technical grade at 15 g/L showed the highest inhibition index of 0.77 ± 0.09. Analysis using Least Significant Difference (LSD) (P < 0.05) showed there was significant difference on the ability of A. flavus UICC 360 to produce lovastatin at different glucose technical grade concentration. High Performance of Liquid Chromatography (HPLC) showed that concentration of 15 g/L glucose technical grade had the same retention time with standard lovastatin at 4.52 minutes and 54.2 mg/L concentration."