In Korea, the agricultural industry has witnessed a growing emphasis on reducing reliance on imported forage by adopting locally available alternatives to enhance sustainability and self-sufficiency. Given the limited information on the potential use of whole-crop rice silage (WCRS) as livestock feed, this study evaluated the effects of total mixed rations (TMR) containing WCRS on the rumen microbiota of Hanwoo heifers. Thirty heifers (body weight = 351 ± 39 kg) were randomly assigned to three TMR diet groups for the early fattening period: oat hay (OH), oat hay with Italian ryegrass silage and corn silage (OIC), and silages from whole-crop rice, Italian ryegrass, and corn (WCRSEF). During the late fattening period, the same heifers (569 ± 40 kg) were reassigned to three other treatment groups: perennial ryegrass (PRG), Italian ryegrass silage and alfalfa hay (IRGA), and silage containing whole-crop rice (WCRSLF). The effects of different feeding diets on the rumen microbial composition of Hanwoo heifers were investigated using high-throughput 16S rRNA gene sequencing. The analysis revealed similar microbial diversity among the treatments across both fattening periods. Bacteroidetes and Firmicutes were the most dominant phyla during early and late fattening periods. Moreover, during the early fattening period, heifers fed WCRS exhibited a higher ratio of Bacteroidetes to Firmicutes, whereas Firmicutes became more predominant in the late fattening period. Hungateiclostridium and Porphyromonas were identified as biomarkers (LDA score > | 2 |; p < 0.05) for the WCRSEF and WCRSLF groups, respectively. Furthermore, the microbial co-occurrence network highlighted different patterns (| r | = 0.85; p < 0.05) between the early and late fattening periods. The results provide significant insights into the effects of WCRS as a substitute for conventional forages such as oat hay, perennial ryegrass, alfalfa, and Italian ryegrass silage. The findings suggest that WCRS can modulate the rumen microbiome of Hanwoo heifers.

무순은 재배 및 유통 과정에서 토양, 용수 및 작업자 등 에 의해 미생물 교차 오염이 발생할 가능성이 높아 미생 물학적 안전성 문제가 지속적으로 제기되고 있다. 본 연구에서는 유통 중인 무순의 미생물 오염도를 조 사하고, 주요 오염 미생물(대장균군, Escherichia coli, Bacillus cereus, Staphylococcus aureus)에 대해 물리적 처 리(자외선, 초음파) 및 화학적 처리(에탄올, 이산화염소수, 차아염소산나트륨, 구연산, 사과산, 식초)를 적용하여 미 생물 저감 효과를 비교하였다. 그 결과, 3% 구연산–사과산 혼합 용액으로 10분간 처 리 시 E. coli, S. aureus, B. cereus가 모두 불검출 수준 으로 감소하였다. 또한 동일 처리 후 수돗물 세척 및 4oC 에서 4일간 저장하는 동안 미생물 재증식은 확인되지 않 았다. 그러나 3% 구연산–사과산 처리 후 1일 이상 저장 시 무순의 신선도가 저하되는 경향이 관찰되었다. 이상의 결과를 종합하면, 무순과 같은 어린잎 채소는 섭취 전까지 냉장(4oC) 보관 후 소비 직전에 3% 구연산 –사과산 혼합 용액으로 10분간 처리하고 수돗물로 세척 하는 방법이 미생물학적 안전성 향상에 효과적인 것으로 판단된다.

The slow cathodic oxygen reduction rate (ORR) of microbial fuel cells (MFCs) is still one of the main bottlenecks in its industrialization. As an ORR catalyst, metal oxides are expected to significantly enhance ORR efficiency by providing active sites, regulating reaction pathways, and enhancing stability. In this paper, four bimetallic oxide catalysts, CuO/Co3O4, CuO/ MnO2, CuO/NiO, and CuO/Fe2O3, were synthesized by sol–gel method, and their structural characteristics were characterized. The results showed that CuO/Co3O4 exhibited the largest specific surface area and optimized pore structure, and the synergistic effect of Cu and Co significantly improved the electrochemical performance. As the cathode catalyst of MFCs, CuO/Co3O4 shows high ORR catalytic activity, low charge transfer resistance, and good stability. In MFCs application, CuO/ Co3O4 catalyst achieved the maximum power density of 227 mW m− 2. In the five-cycle test, the output voltage is stable at about 240 mV, and the COD removal rate reaches 91.9%, which shows great application potential in wastewater treatment.

Microorganisms perform a crucial function in the biogeochemical processes that maintain soil quality. Nonetheless, the influence of biochar on soil microbial communities and their ecological functions remains poorly understood in black soils. To investigate this, a 2-year field experiment was conducted with four biochar application treatments: 0 t ha− 1 (CK), 6 t ha− 1 (BC6), 12 t ha− 1 (BC12), and 24 t ha− 1 (BC24). Microbial diversity and community composition under each treatment were assessed using high-throughput sequencing techniques. PICRUSt2 and FUNGuild were employed to predict microbial functional profiles. Compared to the control (CK), biochar addition led to notable shifts in both bacterial and fungal community structures. It also significantly enhanced bacterial α-diversity, as reflected by increased Shannon index, OTU counts, and Chao1 richness. However, a gradual decline in bacterial diversity was observed with rising biochar application rates. Taxonomic analysis revealed that biochar treatment significantly elevated the relative abundances of specific bacterial groups—such as Acidobacteria, Chloroflexi, Candidatus_Solibacter, and Bryobacter—as well as fungal groups such as Ascomycota, Zygomycota, Mortierella, Penicillium, and Fusarium. These effects were most evident under the moderate application rate (BC6). These microbial community changes may contribute to maintaining agroecological functions and soil health in biochar-amended soils. Regarding ecological functions, biochar application enhanced soil bacterial metabolic potential and saprotrophic fungal abundance, with more significant effects in the BC6 treatment, while reducing plant pathogenic fungi. This suggests beneficial effects on soil health maintenance and elemental cycling. Therefore, from the perspective of soil microbial community characteristics, biochar application positively influences black soil quality improvement. Considering environmental and economic benefits, a lower biochar application rate (6 t ha⁻1) may represent an optimal strategy for carbon sequestration, soil quality enhancement, and agroecological function maintenance in the studied system.

This study examined the applicability of the ATP bioluminescence assay for the efficient screening of paper-based records requiring disinfection for preservation. For the investigation, microbial contamination was measured on the surfaces of six types of paper-based records (fine-print paper, medium-print paper, ground paper, newsprint paper, practice paper, and tracing paper) using two ATP luminometers (Lumitester SMART PD-30 and 3MTM Clean-TraceTM LM1) at the National Archives of Korea. Among the six paper-based record types, medium-quality paper, tracing paper, and fineprint paper exhibited the highest contamination levels, confirming varying degrees of vulnerability based on the materials. RLU values were measured in the records of old drawings from the year 1111 and in records from the year 1831. RLU values were also present in the records from the years 1904 and 1911. The records from the year 1922 showed high RLU values of 3,639 and 2,662 in both ATP luminometers, indicating a very high level of microbial contamination. The RLU of the drawings stored in NF501 storage ranged from 7 to 57 (LM1 measurement) and 64 to 524 (PD-30 measurement). Overall, measurements of records on paper materials that had not been disinfected showed microbial contamination levels ranging from low to very high, and these materials consisted of records dating from 1900 to 2003. Furthermore, the Lumitester SMART PD-30 luminometer yielded significantly higher RLU values than the 3MTM Clean-TraceTM LM luminometer, demonstrating a substantial discrepancy between the two devices. Therefore, to ensure the reliability and efficiency of the disinfection process, it is necessary to standardize the use of ATP-specific detection methods.

A total of 128 halophilic and marine-associated bacterial strains were isolated from environmental marine samples and fermented seafood products collected in the Sacheon region of South Korea. The aim was to secure region-specific microbial resources and evaluate their potential for industrial use. The isolates belonged to 4 phyla, 15 families, 30 genera, and 61 species. The phylum Bacillota, particularly the family Bacillaceae, was the major taxonomic group (62.5%), comprising 14 genera and 36 species, such as Alkalihalobacillus, Bacillus, Caldibacillus, Cytobacillus, Fictibacillus, Halobacillus, Lysinibacillus, Metabacillus, Neobacillus, Oceanobacillus, Priestia, Rossellomorea, Rummeliibacillus, and Ureibacillus. Members of the phylum Pseudomonadota, primarily the family Alteromonadaceae, accounted for 4.7% of the isolates and included the genera Marinobacter and Microbulbifer. All isolates identified as members of the phylum Pseudomonadota were strong auxin producers or showed high extracellular enzyme activities. Functional characterization showed that 86 strains (67.2%) exhibited hydrolytic activity for at least one enzyme (protease, amylase, or lipase), and 32 strains (25%) produced auxin. The functions of the microbial resources in the Sacheon region are highly diverse. Collectively, the isolated strains show potential for application in managing marine environments, bioprocessing, and the fermented seafood industry, underscoring their value as genetic resources for future biotechnological use in South Korea.

본 연구에서는 어린이집 급식실에 설치된 냉장고, 냉동 고, 자외선 살균기 손잡이의 미생물 오염도를 조사하고 위 생 관리 방안을 제시하고자 하였다. 실험에 사용된 손잡 이는 전라남도 소재 어린이집 101곳의 냉장고, 냉동고, 자 외선 살균기를 대상으로 하였다. 냉장고, 냉동고, 자외선 살균기 손잡이의 일반세균 오염도는 평균 1 .9 ±0.9 log CFU/ 100 cm2, 1.9±0.7 log CFU/100 cm2, 2.0±1.1 log CFU/100 cm2로 나타났으며, 자외선 살균기의 오염도가 가장 높게 나타났다. 즉각적인 안전 조치가 필요한 급식 설비 손잡 이 수는 가정 4건, 국공립 6건, 민간 7건으로 민간 어린이 집 급식 설비 손잡이에서 일반세균수 오염에 가장 취약하 였다. 냉장고, 냉동고, 자외선 살균기의 대장균군 오염도 는 평균 1.4±1.4 log CFU/100 cm2, 1.1±1.1 log CFU/100 cm2, 1.1±1.0 log CFU/100 cm2로 나타나 냉장고의 오염도 가 가장 높게 나타났다. 보육시설 별로는 지역아동센터, 가정, 국공립, 민간 어린이집 순으로 높게 나타났다. 즉각 적인 안전 조치가 필요한 급식 설비 손잡이 수는 지역 아 동 0건, 가정 2건, 국공립 5건, 민간 10건으로 민간 어린이집 급식 설비 손잡이에서 대장균군 수 오염에 가장 취 약하였다. 어린이집 급식실 설비 손잡이의 살균 기준을 제 시하고자 대장균 저감화 효과를 실험하였다. 소독 티슈와 70% 에탄올을 이용하여 실험한 결과, 어린이집 급식실 설 비 손잡이를 살균할 시 소독 티슈를 새것으로 바꾸어 총 3회 살균하는 방법과 70% 에탄올 4회 분무 후 5분 건조 하는 방법이 가장 적합한 방법으로 나타났다. 이러한 결 과를 종합하여 볼 때, 어린이집 급식실 설비 손잡이에 의 한 교차오염을 예방하기 위하여 설비 손잡이를 소독 티슈 새것으로 교체하며 총 3회 이상 살균하거나, 70% 에탄올 4회 이상 분무 후 자연 건조하는 방법을 활용하여야 할 것으로 판단되었다.

Heavy metal contamination from abandoned mines presents long-term risks to soil ecosystems by altering physicochemical conditions and limiting microbial functions. To investigate these effects, we analyzed soils from the Deoksan Pb-Zn abandoned mine in Korea using community-level physiological profiling (CLPP) with Biolog EcoPlateTM. Soil samples were collected from three contaminated sites and one uncontaminated control, and we assessed their physicochemical properties, heavy metal concentrations, and microbial substrate utilization patterns over a 7-day incubation period. The results revealed significant site-specific differences in soil chemistry, with Zn and Pb concentrations exceeding ecological safety thresholds near the mine adit. Average well color development (AWCD) increased over time across all sites, but functional trajectories differed: highly contaminated soils exhibited prolonged increases, while low-contamination soils plateaued earlier. Substrate utilization patterns shifted over time, with carbohydrates and carboxylic acids dominating in the early incubation phase, while phosphorylated chemicals became more prominent in later stages. Multiple regression and relative importance analyses identified Cd, Pb, and Zn as key regulators of substrate utilization, with phosphorylated chemicals showing strong negative correlations (R 2>0.95). These findings indicate that heavy metal stress not only decreases overall microbial activity but also disrupts specific metabolic pathways. The utilization of phosphorylated chemicals emerged as a particularly sensitive functional indicator, underscoring its potential for ecological risk assessment and soil health monitoring in contaminated sites.

The commercial feed additive, native rumen microbes (RC), derived from a diverse microbial community isolated from the rumen of Hanwoo steers is being explored to enhance rumen fermentation and improve ruminant feed utilization. This study evaluated the impact of native rumen microbes supplementation on methane emissions, microbial diversity, and fermentation efficiency on in vitro assessment. Treatments were as follows: CON (basal diet, without RC); T1 (basal diet + 0.1% RC); T2 (basal diet + 0.2% RC). Rumen fermentation parameters, total gas, and methane production were assessed at 12, 24, and 48 h of incubations. The in vitro gas production was carried out using the Ankom RF Gas Production System. Supplementation of RC significantly reduced the total gas production at 12, 24, and 48 hours of incubation (p < 0.05). Volatile fatty acid concentrations were increased, while acetate and propionate were decreased (p < 0.05) at 48 h by the supplementation of RC. Notably, the 0.1% inclusion level of RC significantly reduced methane production by 28.30% and 21.21% at 12 and 24 hours. Furthermore, microbial diversity analysis revealed significant shifts (p < 0.05) in bacterial composition between the control and treatment groups, while supplementation also promoted the growth of bacterial populations, such as Succiniclasticum. These findings suggest that native rumen microbes supplementation, particularly at 0.1% inclusion level, can enhance rumen microbial composition while significantly reducing methane production in vitro.

This study was conducted to investigate the effects of supplementation of direct-fed microbials (DFMs) during the growing and finishing periods on growth performance and carcass characteristics in Hanwoo steers. DFMs were administered only during the first 3 months after arrival and the final 3 months before slaughter, and the feeding trial lasted for 740 days. During the growing phase, the treatment group showed a significantly higher average daily gain (ADG) of 0.89 kg compared to 0.80 kg in the control group (p<0.05). No significant differences were found between groups during the fattening phase. In the finishing phase, ADG was significantly higher in the treatment group (0.59 kg vs. 0.53 kg; p<0.05), although concentrate intake increased by 6.17% without statistical significance. At the end of the entire feeding period, the treatment group had a higher final body weight (803.05 kg vs. 763.51 kg), and overall ADG was significantly greater (p<0.05). For carcass traits, cold carcass weight was significantly higher in the treatment group (p<0.05), while no significant differences were observed in backfat thickness, loin eye area, or marbling score. However, the proportion of carcasses graded 1++ was higher in the treatment group (50.0%) than in the control group (30.0%). In conclusion, supplementation of direct-fed microbials during the growing and finishing periods improved average daily gain and increased the proportion of carcasses with higher quality grades in Hanwoo steers.

복숭아혹진딧물(Myzus persicae Sulzer, Hemiptera: Aphididae)은 채소작물, 과수작물과 화훼작물에 발생하여 농업과 원예작물에 경제적 피해를 주는 주요 해충이다. 복숭아혹진딧물과 기주내부 미생물간의 상호작용을 이해하기 위해, 격리된 사육시설에서 약 2년간 누대사육된 복숭아 혹진딧물 내의 미생물 군집구조는 16S rRNA gene을 이용하여 분석하였다. 복숭아혹진딧물에 우점하는 미생물은 γ-proteobacteria에 속하는 Buchnera sp., Pseudomonas sp., Propionibacterium sp. 등이 주요 우점하는 것을 확인되었다. 미생물 군집크기분석은 정량 PCR을 통해 분석하였 으며, 박테리아 군집의 크기가 곰팡이 군집보다 약 4,300배 큰 것을 확인하였다. 이러한 결과로부터 복숭아혹진딧물 내부에는 γ-proteobacteria 에 속하는 Buchnera sp.가 기주와 매우 밀접한 상호관계가가 이루어진다고 판단되어진다. 본 연구의 결과는 복숭아혹진딧물과 기주내부 미생물간 의 상호작용을 이해하는데 기초자료로 제공될 수 있을 것으로 기대된다.

진저 비어는 생강과 설탕을 이용한 발효 음료로, 가볍 게 탄산화된 특유의 매운맛이 특징이며, 주로 가정에서 직 접 만들어진다. Ginger bug라는 스타터 컬처를 사용한 자 연적 발효 과정을 통해 만들어지며, 이는 상업용 음료와 달리 발효된 상태의 살아있는 미생물을 포함한다. 이 연 구는 두 가지 다른 방법으로 가정용 진저 비어를 직접 제 조하여 진저 비어의 미생물 군집의 변화를 분석하고자 하 였다. 레시피 1과 2의 발효 결과, 총 균수(aerobic plate count, APC)는 최대 6 log CFU/mL에 도달했고, 효모와 곰팡이 수(yeast and mold, YM)는 6.5 log CFU/mL로 가 장 높았다. 레시피 2에서는 진저 비어를 만들기 전에 ginger bug를 발효하였으므로 알코올 함량이 0.655%까지 증가한 반면, 레시피 1에서는 0.15% 미만이었다. 다양성 분석 결 과, ginger bug에서 높은 수준의 Enterobacteriaceae가 발견 되어 발효 과정과 재료 취급이 미생물 군집 변화에 영향 을 미쳤음을 시사했다. 생강과 진저 비어 전반에서 Lactococcus가 낮은 수준으로 검출되었고, 진저 비어에서 는 셀룰로오스를 분해하는 Trabulsiella 균주가 발견되어 프로바이오틱스 가능성을 시사하였다. 본 연구는 진저 비 어의 미생물 군집에 대한 최초의 연구로, 진저 비어 제조 시 재료로부터 기원한 미생물이 어떻게 변화하는지에 대 한 통찰을 제공한다. 또한, 다양한 환경에서의 발효 조건 이 미생물 군집과 제품의 품질에 미치는 영향을 탐구하는 데 기여할 것이다. 연구 결과는 진저 비어의 품질 향상에 대한 향후 연구에 중요한 자료를 제공할 것이다.