Angkak, a fermentation product of rice by Monascus sp., is used for natural food coloring, spices, and medicine by Indonesian people who believe in its pharmacological properties. However, Monascus sp. also produces a secondary metabolite, hepato-nephrotoxic mycotoxin citrinin. The biosynthesis of pigments and citrinin is generated from a tetraketide point in the polyketides pathway. This study aims to detect the levels of citrinin and examine its relationship with the color of angkak in Indonesia. Thirty samples were collected from eight different sites in Indonesia. ELISA method was used to detect the citrinin content. Meanwhile, the color analysis was based on the CIE L*a*b* system and the measurement of its pigments was conducted using spectrophotometer UV-vis. All samples were grown on PDA (Potato Dextrose Agar) media. Mold contamination was found, ranging from 1.67% to 85.33%. The results of citrinin content measurement of the angkak ranged from 17.94 ppm to 142.74 ppm. The color measurement showed that the angkak color was various, from bright red (L* 44.78, a* 21.54, b* 8.67) to very dark red (L* 35.62, a* 17.32, b* 5.43). The ethanol-soluble yellow (OD400) and red (OD500) pigment contents were in the ranges of 83.80 AU/g to 306.52 AU/g and 100.86 AU/g to 318.18 AU/g, respectively. However, based on the Pearson correlation analysis, there was no correlation between the citrinin content and the color value of angkak.

Currently in Cisauk area, there are still a lot of trashes lying on the streets, ditches, rivers, and other public places. The government has encouraged all citizens to sort out garbage and process organic waste into compost. However, not many people comply with this encouragement due to their ignorance or lack of knowledge about practical composting methods. This study aimed to improve social awareness in managing and processing organic domestic waste into compost using Takakura home composting method, which is easy, inexpensive, and odorless. Moreover, different home-made compost starters with different mixed microbial inoculants were compared. The study included microbial inoculant preparation, home-made compost starter production from rice husk and rice bran, and compost production in Takakura basket. The methods were taught through a series of workshop in Bermis Serpong Asri Residence, Cisauk, Tangerang. Through this effort, the problem of domestic organic waste was expected to be overcome. Moreover, the product of Takakura home composting can be used as plant and soil fertilizer, or even sold to increase family income.

Abstract. Barus T, Halim R, Hartanti AT, Saputra PK. 2019. Genetic diversity of Rhizopus microsporus from traditional inoculum of tempeh in Indonesia based on ITS sequences and RAPD marker. Biodiversitas 20: 847-852. The main microorganism for tempeh fermentation is Rhizopus microsporus. These days, many tempeh producers use commercial inoculum, such as ‘Raprima’ as resource of R. microsporus. As a result, the genetic diversity of R. microsporus that had been reported in Indonesia has diminished. Information about genetic diversity is needed as a basis to select R. microsporus as tempeh inoculum. This research aims to investigate the genetic diversity of R. microsporus from waru leaves based on Internal Transcribed Spacer (ITS) Sequence and Random Amplified Polymorphic DNA (RAPD) markers. A total of 25 R. microsporus were isolated from traditional inoculum waru leaves (Inoculum 1) and traditional inoculum other than waru leaves (Inoculum 2). Amplification of ITS sequence was done using universal primer pairs of ITS-4 and ITS-5. Amplification of RAPD markers was done using primers OPC-08, OPC-19, OPQ-6, R-108, OPA-09 and OPJ-20. ITS sequence was not sufficient to compare the similarities among R. microsporus. On the other hand, RAPD markers successfully compared the similarities among 25 R. microsporus. A total of 25 R. microsporus were divided into 9 clusters. R. microsporus from Inoculum 1 grouped into Cluster 1, Cluster 3 and Cluster 4-8. Inoculum 2 grouped into Cluster 2 and Cluster 9. R. microsporus from tempeh grouped into Cluster 4 and was different from Inoculum 1 and Inoculum 2, except for TB3.

Agricultural products may easily perish if they are not well taken care of during postharvest treatment. One of the main causes in damaged products is the biological contamination of pathogenic fungi, such as Rhizopus spp. that gives rise to Rhizopus rot symptoms. The purpose of this research was to isolate Rhizopus spp. from different agricultural products showing Rhizopus rot symptoms as well as to identify them. Rhizopus pure cultures were isolated on potato dextrose agar.  Identification was done through molecular techniques using PhytopureTM DNA Extraction Kit and Maxwell® RSC Plant DNA Kit for DNA isolation, internal transcribed spacer (ITS4 and ITS5) as primers for amplification, and molecular evolutionary genetics analysis 7 (MEGA7) for the reconstruction of phylogenetic tree from sequence result. The phylogenetic tree using Maximum Likelihood statistics with 1,000 replications of bootstrap test showed five strains, namely AR9, AR10, AR11, AR13, and AR14, which belong to R. delemar, and the other seven remaining strains, AR1-AR7 belong to R. stolonifer. Identification was clarified with morphological and physiological data using Rhizopus growth at temperature control of 33 and 42°C as well as microscopic observation involving rhizoid, columella, measurement of sporangiospores, and sporangiophores.