## 3 Results
### Impacts of the Various SCG Extracts on the Growth of Potential Plant Growth-Promoting Bacteria  
The potential plant growth promoting bacteria (SB-3 and SB-4) selected from phytotoxicity analysis were tested to find their growth status in the three different media (Figure 4). The extraction of SCGs using distilled water by heat treatment at 121 \({}^{\circ}\)C for 15 min showed the highest CFU/mL of each culture of both bacteria. The SGC media extracted with 80% ethanol at room temperature produced considerable growth of SB-3 with a log\({}_{10}\) CFU/mL of 9.72, and a lower CFU/mL for SB-4. SB-3 (A) and SB-4 (A) showed higher population densities (log\({}_{10}\) CFU/mL = 9.72 and 9.99, respectively) compared to those grown in other extracts. The extraction of SCGs using distilled water by a shanking incubator (150 rpm) at 25 \({}^{\circ}\)C for one hour produced a somewhat high CFU/mL with SB-3, whereas SB-4 was hardly observed in the plates due to indigenous bacterial contamination from the spent coffee grounds. Therefore, SCG extraction (10%, \(w/w\) in water) by heat treatment (121 \({}^{\circ}\)C for 15 min) may be commercially applicable to culturing plant-growth-promoting bacteria. Computing Process Monitoring, Physico-Chemical Analysis, and Maturity Quality Test of the Manufactured Composts  
The temperature and moisture content were monitored for the composting treatments. A total of 1.2 kg of substrate mixture (NC and Tr_1) and 5 kg (Tr_2, Tr_3, Tr_4, and Tr_5) were composted, where the highest temperature reached was 55 \({}^{\circ}\)C, which then decreased to 30-36 \({}^{\circ}\)C. The temperatures were maintained during the whole 14 days of composting. The moisture content was adjusted every two days to 50-55% due to the high temperature. The quality control data of the functional composts manufactured are shown in Table 5. The representative composts (Tr_1 and Tr_5) met all the commercial quality standards approved by the Office of Rural Development of the South Korean government. Tr_5 carried higher contents of organic matter, total phosphorus, and total potassium than Tr_1, probably due to the significantly higher content of rice bran in Tr_5. Figure 3: Analysis of the inhibitory effect of _Streptomyces sasae_ St-3 on phytopathogens (_Fusarium oxysporum f_. sp. _lycersici_ (KACC 40032) (**a**), _Fusarium oxysporum f_. sp. _lactuca_ (KACC 42795) (**b**), _Pythium ultimum_ (KACC 40705) (**c**), and _Pythium_ sp. (KACC 40581) (**d**)). To analyze the physio-chemical properties and maturity quality, we performed a phytotoxicity test. The composets were diluted ten times, and the germination index and the weight of the grown plants were monitored using radish and pepper plants. The germination index of Tr_5 was 49% higher than the NC and 5.6% higher than Tr_4. The addition of SB cultures and St-3 might be the reason for the enhancement in GI in Tr_5. The bioaugmented Tr_5 was higher in radish plant weight by 58%, and 48% higher in pepper  
Figure 4: Effects of various SCG extracts on the growth of potential plant growth-promoting bacteria. (**A**) SCG in distilled water (10%, \(w/w\)) and extracted by heat treatment (121 \({}^{\circ}\)C for 15 min); (**B**) SCG in distilled water (10%, \(w/w\)) and extracted by a shaking incubator (150 rpm) at 25 \({}^{\circ}\)C for 1 h; (**C**) SCG suspended in 80% ethanol (10%, \(w/w\)) and extracted by a shaking incubator (150 rpm) at 25 \({}^{\circ}\)C for 1 h. Letters above the error bar indicates the comparison of samples using Duncan’s test.