The success of in vitro cultivation, particularly for micropropagation purposes, depends on the efficient control of contaminants. In this context, the sterilization of plant material constitutes a fundamental step in initiating cultures. Microbial contaminants can be found either on the surface (epiphyte) or inside plant explants (endophyte). However, the latter is generally challenging to detect and may not always be eradicated through surface sterilization alone. Endophyte contaminants, such as bacteria, can persist within plant material over several cultivation cycles, potentially interfering with or inhibiting in vitro establishment, growth, or recovery of cryopreserved materials. Therefore, microscopy techniques, such as electron microscopy, can yield valuable insights into bacterial endophytes\' localization, tissue colonization patterns, and functions in in vitro plant culture. This information is essential for adopting effective strategies for eliminating, preventing, or harmonious coexistence with contaminants.

Periodic assessment of bacterial contamination is necessary as it allows proper guidance in cases of eye infections through the use of appropriate antibiotics. Due to the extensive use of antibiotic treatment, many strains of the microbiota that cause infections are resistant to the usual ophthalmic antibiotics. The present study provides an updated assessment of the susceptibility of Gram-positive and Gram-negative bacteria found on the ocular surface to the most commonly used antibiotic agents in patients undergoing cataract surgery. A total of 993 patients were included in the study with ages between 44 and 98 years old. Conjunctival cultures were collected 7 days before cataract surgery. The response of Gram-positive and Gram-negative bacteria to various antibiotic classes, such as glycopeptides, cephalosporins, carbapenems, fluoroquinolones, aminoglycosides, phenicols, tetracyclines, rifamycins, macrolides and penicillins, was assessed. From the tested antibiotics, vancomycin had 97.8% efficacy on Gram-positive bacteria. In the cephalosporin category, we observed a high level of resistance of the cefuroxime for both Gram-positive and negative bacteria. Antibiotics that have more than 90% efficacy on Gram-positive bacteria are meropenem, imipenem, netilmicin, amikacin and rifampicin. On Gram-negative bacteria, we found 100% efficacy of all tested fluoroquinolones, i.e., aminoglycosides (except for tobramycin), doxycycline, azithromycin, clarithromycin and chloramphenicol. The current study illustrates patterns of increased resistance in certain bacteria present on the ocular surface to some of the commonly used antibiotics in ophthalmological clinical practice. One such revealing example is cefuroxime, which has been highly used as an intracameral antibiotic for the prevention of bacterial endophthalmitis after cataract surgery.

Bacterial contamination is a critical parameter for how long a medical mask will be worn.
In this study, we used the pour plate method to observe the total bacteria counts in used medical face masks. The bacterial community analysis was detected using bio-Mass spectrometry technology and 16SrRNA gene sequencing technology. The wearing time of the mask from 0.5 hours to 5 hours were studied.
These results shown that the total number of bacteria on the inside surface of the mask were higher than the outside. The total number of bacteria on the inner surface of masks worn for 0.5 h, 1 h 2 h, 4 h and 5 h was 69 CFU/m2,91.3 CFU/m2, 159.6 CFU/m2, 219 CFU/m2, and 879 CFU/m2, respectively. The total number of bacteria on the outside surface of masks worn for 0.5 h, 1 h 2 h, 4 h and 5 h was 60 CFU/m2, 82.7 CFU/m2, 119.8 CFU/m2, 200 CFU/m2, and 498 CFU/m2, respectively. The bacterial abundance obtained from bio-Mass spectrometry were consistent with the results of 16SrRNA sequencing. Both the methods discovered the maximum number of Neisseria followed by Corynebacterium species in mask worn 5 hours. The top 100 bacteria isolated from inside and outside surface of mask belong to 11 phyla.
We analyzed bacterial penetration efficiency of the bacteria that were detected both on the inside and outside surface of the masks. In the top 10 bacteria, no bacteria were detected both inside and outside the mask worn for four hours, while 6 bacteria species were detected on the inside and outside of the mask after wearing for five hours. Bacterial penetration rates ranged from 0.74% to 99.66% for masks worn continuously for five hours, and the penetration rate of four strains exceeded 10% in the top 10 colonies. We recommend timely replacement of masks worn for more than four hours.

Porcine breeding today is based on artificial insemination with chilled semen. This is stored at 5 °C with antibiotic supplementation to avoid bacteriospermia. There are many negative consequences on sperm quality and functionality as a result of bacterial contamination, as well as on the health of the sow. Nowadays, various techniques are being developed to reduce the indiscriminate use of antibiotics and thus avoid the generation of antibiotic resistance genes. This review aims to inform about the bacterial contamination consequences of storing liquid semen from boar and to provide an update on current methods and alternatives to antibiotic use in cold storage.

The role of cockroaches in the cause of disease or human infections is not immediately obvious. The present study aimed to review the currently available research on the potential role of cockroaches in the transmission of pathogenic bacteria and bacteria with antibiotic resistance.
A scoping review included the studies published for a period between January 2001 and December 2020. A search was performed through five databases, namely, PubMed, Sage, Springer, Sabinet, and Science Direct. A search strategy used was conducted according to the principles of Preferred Reporting Item for Systemic Reviews and Meta-Analyses (PRISMA). From 97 studies identified, 32 studies were included in the scoping review.
The findings indicate that cockroaches may be a potential vector for a diverse range of pathogenic bacterial agents. Most bacterial agents isolated are antidrug-resistant and antibiotic-resistant which is considered the greatest threat to public health in the current period.
Cockroach infestation should be considered as a serious concern, given the possible role of cockroaches as reservoirs of antibiotic-resistant bacteria. Further research is needed which can provide a comprehensive understanding of the role of cockroaches in transmitting human infections.

Groundwater is an important water source to consider when ensuring the safety of urban water supply. Groundwater contaminated by bacteria poses a potential health risk to the drinking water supply. This study focuses on the water supply of Liuzhou City, a famous industrial city in China. Analyses of the concentrations, spatial distribution, and pollution sources of bacteria in the groundwater were conducted based on samples collected from 27 wells during the wet and dry seasons in 2018. The total colony counts and total coliform were high during both the wet and dry seasons, posing a severe threat to the emergency water supply security for more than one million people in the city. The groundwater in Liuzhou City is generally contaminated by bacteria, with higher pollution levels in the northern urban-rural fringe and central urban areas. Domestic pollution is the main sources of groundwater bacteria. In addition, bacterially contaminated rivers (Liujiang River) passing through the urban area likely transfer bacteria to the groundwater due to the circulation of the groundwater and surface river water. Controlling the bacterial pollution of groundwater in this region requires adherence to a long-term management plan.

Microorganisms live almost everywhere, they are even present on inanimate objects such as Mobile phones, as a result contaminates our body. The main purpose of this study was tantamount to compare microbial contamination of keypad and touch screen mobile cell phones between hospital and non-hospital staffs. Samples were collected from 456 cell phones of hospital and non-hospital. Microbial swab samples were taken from 1 cm2 of surface from each cell phone, and incubated on Brain Heart Infusion agar media at 37.5 °C for 24 h. Isolated microorganisms were grown aerobically on 55% defibrinated Sheep Blood and eosin methylene blue agar media at 37.5 °C for 48 h. In present study the antibiotic microorganism-resistant could not be observed. Overall, 456 cell phones were collected: 240 (52.63%) from hospital staff (nurses), 216 (47.36%) from non-hospital staff (health care worker outside the hospital). The result indicates that the bacterial contamination of phones used by all of different investigated groups was lower in touch screen devices than keypad devices and the contamination was found more in hospital staff cellphone than non-hospital staff׳s cell device. Woman׳s cell also has a few colonies rather than man׳s cell phones. The dominant microorganisms in the hospital staff were, Enterobacteriaceae, Bacillus species, especially Gram-positive bacteria sporulated and staphylococcal negative coagulase, respectively. Cell phones could be a serious threat to the spread of cross-infection in hospitals, therefore development of hand hygiene and cell phone cleaning guidelines is needed regarding public cell phone use.