Search

Melanoma, a type of cancer that most often occurs on skin exposed to UV rays, is becoming increasingly common. Recent research has focused actively on using natural products. The goal of this study was to compare the melanin-inhibitory effects of Hibiscus (Hibiscus sabdariffa L.) flower Extract (HE) and Niacinamide (NA), a functional ingredient with whitening effects, on melanoma cells. The 3-(4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the effects of HE (1, 3.5, 7, 10, and 14 μg/mL) and NA (1, 5, 10, 20, and 25 μg/mL) on cell viability. A lactate dehydrogenase cytotoxicity assay was employed to confirm the cytotoxic effect of HE and NA on mouse melanoma cells. The real-time reverse-transcription polymerase chain reaction was performed to analyze Tyrosinase (TYR), Tyrosinase-Related Protein (TRP), and Microphthalmia-associated Transcription Factor (MITF) mRNA expression levels to determine whitening effects. Vitamin C (VC, 10 µg/mL) was selected as a control. The MTT assay showed that HE and NA were non-cytotoxic at <10 μg/mL in B16F10 cells when compared to the control, VC. The cytotoxicity of HE was confirmed to be lower than the control (VC) when a concentration of 7 µg/mL or lower was applied. The cytotoxicity of NA was low even at a concentration of 10 µg/mL. HE showed greater whitening effects at lower concentrations (i.e., 1 µg/mL) than VC (10 µg/mL). HE had almost no cytotoxicity compared to NA and VC, and the expression levels of whitening inhibition genes MITF and TYR were higher than VC, indicating that it can be used as a healthy functional food or cosmetic material.

This study assessed the clinical characteristics, epidemiological trends, and changes associated with major pathogens causing gastrointestinal inflammation. We retrospectively analyzed the test results of hospitalized patients who were administered a mPCR test for diarrhea causing bacteria between June 2010 and December 2019 at the Cheonan Dankook University hospital in the Republic of Korea and identified clinical characteristics and epidemiological trends related to major pathogens causing gastrointestinal inflammation. Our results showed that infections due to Clostridium perfringens, Escherichia coli H7, Campylobacter species (spp.), and Clostridioides difficile toxin B varied seasonally (March to October). When examining annual trends, we found that Escherichia coli H7 incidence decreased significantly throughout the time frame examined, from 27.27% of total infections in 2010 to 8.93% in 2019. In contrast, the incidence of both Clostridium spp., and Campylobacter spp. gradually increased throughout this time frame. Our study was able to demonstrate that improvements in environmental hygiene have aided in reducing the occurrence of water borne diarrhea, while infections due to food borne, anaerobic and diarrhea causing bacteria, such as those present in non-sterile milk and poultry, are increasing. We believe that this study will serve as a useful resource for better understanding the dynamics and risks associated with bacterial diarrhea, including infections caused by Campylobacter spp.