Dammarane-type Saponins from the Leaves of Vietnamese Ginseng (Panax vietnamensis Ha & Grushv.) and Their Acetylcholinesterase Inhibition In Vitro and In Silico.

Vietnamese ginseng (Panax vietnamensis Ha & Grushv.) represents one of the famous Panax spp. for valuable applications in both traditional and modern medicine; in which, its rhizome part has mainly been used as the medicinal materials based on the bioactive ginsenosides such as ginsenoside Rb1, ginsenoside Rg1, ginsenoside Rd, and majonoside R2. In modern medicine, the development of medicinal materials and utilization of medicinal plants are crucially based on standard bioactive ingredients, so this study to evaluate the leaves of Vietnamese ginseng as source of bioactive ginsenoside led to the identification of seven ginsenosides (1-7). Of them, ginsenoside Rd (2) and pseudoginsenoside RS1 (5) showed inhibitory effects on acetylcholinesterase in vitro with the IC50 values of 47.13 and 79.58 µM and supported by molecular docking analysis, in which ginsenoside Rd (2) and pseudoginsenoside RS1 (5) could play as allosteric inhibitors with high binding affinity (-8.5 and -9.4 kcal/mol) as evidenced by hydrogen bonding and hydrophobic interactions. The findings provided the scientific evidence for using the leaves of Vietnamese ginseng as an alternative source to the roots to enhance memory in traditional medicine as well as for further research on the anti-dementia effects of 2 and 5.

Intersectionality of HIV Stigma with Female Identity: An Investigation among Women Living with HIV/AIDS in Vietnam.

Women living with HIV/AIDS (WLHA) in Vietnam encounter challenges stemming from HIV-related stigma and gender disparities. This study delves into the intersectionality of HIV-related stigma and gender disparities as perceived by WLHA. A cross-sectional survey was conducted among 91 WLHA in Hanoi, Vietnam. Two sets of identically worded scales were used to measure awareness, agreement, and application of stigma towards people living with HIV/AIDS (PLHA) and WLHA. A larger difference between stigma scores towards WLHA and that of PLHA represents a higher level of female-specific stigma. Univariate analyses and multiple regressions were conducted to identify demographic and psycho-social factors associated with the gendered differences in stigma measures. Multiple linear regression showed that WLHA who were currently married were more likely to apply stigma concepts to themselves due to gender identity (adjusted beta coefficient (aBeta Coef) = 0.223). Psychological capital was negatively associated with awareness of stigma towards female identity (aBeta Coef = -0.261). A higher perceived norm in women's equity and power was associated with less self-application of female-specific stigma (aBeta Coef = -0.294). Our findings underscore the importance of addressing psychological well-being and promoting gender equity norms as essential components in the efforts to reduce female-specific HIV-related stigma in WLHA.

Rifampicin tolerance and growth fitness among isoniazid-resistant clinical Mycobacterium tuberculosis isolates from a longitudinal study.

Antibiotic tolerance in Mycobacterium tuberculosis reduces bacterial killing, worsens treatment outcomes, and contributes to resistance. We studied rifampicin tolerance in isolates with or without isoniazid resistance (IR). Using a minimum duration of killing assay, we measured rifampicin survival in isoniazid-susceptible (IS, n=119) and resistant (IR, n=84) isolates, correlating tolerance with bacterial growth, rifampicin minimum inhibitory concentrations (MICs), and isoniazid-resistant mutations. Longitudinal IR isolates were analyzed for changes in rifampicin tolerance and genetic variant emergence. The median time for rifampicin to reduce the bacterial population by 90% (MDK90) increased from 1.23 days (IS) and 1.31 days (IR) to 2.55 days (IS) and 1.98 days (IR) over 15-60 days of incubation, indicating fast and slow-growing tolerant sub-populations. A 6 log10-fold survival fraction classified tolerance as low, medium, or high, showing that IR is linked to increased tolerance and faster growth (OR = 2.68 for low vs. medium, OR = 4.42 for low vs. high, p-trend = 0.0003). High tolerance in IR isolates was associated with rifampicin treatment in patients and genetic microvariants. These findings suggest that IR tuberculosis should be assessed for high rifampicin tolerance to optimize treatment and prevent the development of multi-drug-resistant tuberculosis.

Disclosure of HIV Status in Healthcare Settings: Practices and Considerations among Women Living with HIV/AIDS in Vietnam.

OBJECTIVE: This study investigated women living with HIV/AIDS (WLHA)'s practices and decision-making regarding disclosure of HIV status in healthcare settings in Vietnam. Introduction: Disclosure of HIV status in healthcare settings is under-studied. METHODS: We conducted in-depth interviews with 30 WLHA in Hanoi, Vietnam. Thematic analysis was conducted to investigate the patterns, considerations, and consequences of HIV disclosure. Results: Most participants chose a selective disclosure strategy based on the type of procedure and healthcare setting. They considered several factors: concerns about stigma/discrimination, risks of confidentiality breach, relevance to healthcare provision, and altruism towards protecting providers and other patients. Selective disclosure or non-disclosure often prevented participants from accessing comprehensive care. Conclusion: The study underscores the need to prepare WLHA to make informed decisions regarding disclosure and provide them with service navigations and support. It also highlights the necessity of reducing stigma and enhancing confidentiality protection to ensure safe disclosure in healthcare settings.

Telling Healthcare Providers About HIV Status: How Women with HIV/AIDS in Vietnam Decide and What They ConsiderThis study focuses on how women living with HIV/AIDS in Vietnam decide to share their HIV status with healthcare providers. We interviewed 30 women with HIV/AIDS in Vietnam and found that many choose to reveal their status only in certain situations, depending on the medical procedure and the setting. They weigh various factors before deciding to disclose, including the risk of facing stigma, the need to protect their privacy, how relevant their HIV status is to their other health issues, their wish to protect their healthcare providers and other patients, and how they have been advised by HIV specialists. Unfortunately, choosing not to disclose their status sometimes stops them from getting the full range of medical care they need. The findings stress the importance of helping these women make well-informed choices about disclosing their HIV status. We also need to provide them with additional support and navigational help through healthcare services. Moreover, reducing stigma in healthcare, enhancing providers' ability to gather necessary health information, and ensuring patient privacy are crucial to encouraging more open discussions of HIV status in medical settings.

Green synthesized silver nanoparticles, a sustainable approach for fruit and vegetable preservation: An overview.

Nanotechnology in which silver nanoparticles (AgNPs) have received more interest in fruits and vegetables (FaV) preservation due to their anti-microorganism properties. There are various approaches to synthesizing AgNPs, in which biological reduction, especially plant extraction containing bioactive compounds, is considered non-toxic, eco-friendly, and economically viable. AgNPs can be applied for FaV preservation by immersing or incorporating AgNPs into the edible coating or wrapper film. Depending on the type of coating and the kind of FaV, choosing the coating components is necessary to ensure the anti-microorganism ability and improve preservation efficiency. This review highlights green-synthesized AgNPs for preserving FaV. The study covered the materials employed in the green synthesis of AgNPs, their effectiveness against microorganisms, the influence of AgNPs on film structure, safety properties, and various preservation strategies. Using plant or bacterial-synthesized AgNPs in edible coatings offers a sustainable approach to enhance safety, edibility, environmental friendliness, and FaV quality during storage.

Evaluation of the conformity of intensity-modulated radiation therapy and volumetric modulated arc therapy using AAPM TG 119 protocol.

The aim of this work was to evaluate the conformity of intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), and verify the accuracy of the planning and delivery system used in this work based on the AAPM TG-119 protocol. The Eclipse 13.6 treatment planning system (TPS) was used to plan the TG-119 test suite, which included four test cases: MultiTarget, Prostate, Head/Neck, and C-Shape for IMRT and VMAT techniques with 6 MV and 10 MV acceleration voltages. The results were assessed and discussed in terms of the TG-119 protocol and the results of previous studies. In addition, point dose and planar dose measurements were done using a semiflex ion chamber and an electronic portal imaging device (EPID), respectively. The planned doses of all test cases met the criteria of the TG-119 protocol, except those for the spinal cord of the C-Shape hard case. There were no significant differences between the treatment planning doses and the doses given in the TG-119 report, with p-values ranging from 0.974 to 1 (p > 0.05). Doses to the target volumes were similar in the IMRT and VMAT plans, but the organs at risk (OARs) doses were different depending on the test case. The planning results showed that IMRT is more conformal than VMAT in certain cases. For the point dose measurements, the confidence limit (CLpoint) of 0.030 and 0.021 were better than the corresponding values of 0.045 and 0.047 given in the TG-119 report for high-dose and low-dose areas, respectively. Regarding the planar dose measurements, the CLplanar value of 0.38 obtained in this work was lower than that given in the TG-119 report (12.4). It is concluded that the dosimetry measurements performed in this study showed better confidence limits than those provided in the TG 119 report. IMRT remains more conformal in certain circumstances than the more progressive VMAT. When selecting the method of delivering a dose to the patient, several factors must be considered, including the radiotherapy technique, energy, treatment site, and tumour geometry.

Correction: The effect of M. tuberculosis lineage on clinical phenotype.

[This corrects the article DOI: 10.1371/journal.pgph.0001788.].

Class II Correction and Crowding Treatment Using In-House Direct Printed Clear Aligners: A Literature Review and Case Report.

Clear aligner therapy has significantly improved orthodontic treatment by offering patients a more aesthetically pleasing option compared to traditional braces. This literature review and case report specifically focus on the effectiveness of directly printed clear aligners in treating Class II malocclusions and crowding. Class II malocclusions are characterized by excessive overjet, which often results from skeletal or dental discrepancies between the upper and lower jaws. Crowding refers to the lack of space for teeth within the dental arch, leading to misalignment and potential functional issues. The review and case report highlight the increasing importance of directly printed clear aligners in modern orthodontics and provide clinicians with a valuable tool to effectively address complex malocclusions and crowding while also meeting patient needs for discretion and comfort. Further research is necessary to validate the long-term stability and outcomes of directly printed clear aligner therapy in various orthodontic cases. A detailed case report demonstrates the successful treatment of a patient with Class II malocclusion and mild crowding using directly printed clear aligners. Treatment outcomes include improvements in dental alignment, occlusion, and facial aesthetics, showcasing the effectiveness of this innovative approach.

HPTLC sequentially coupled to UV and SERS: A cost-effective tool for confirmative identification and quantitation of sildenafil in falsified herbal products.

The detection of falsified drugs usually requires multi-disciplinary analysis for confirmative identification. Among hyphenated techniques with high specificity detection, thin-layer chromatography coupled with surface-enhanced Raman spectroscopy (TLC-SERS) is an efficient choice, especially for herbal products with diversified matrix. In this study, HPTLC was coupled to two detection techniques: UV absorption and Raman scattering with silver colloid enhancement for the analysis of sildenafil adulterated in herbal products. With this approach, orthogonal UV and SERS spectral data was collected, so that confirmative results could be obtained within a single TLC analysis. How this approach helped to reduce chances of false positive or false negative results was also discussed. The HPTLC sequentially coupled to UV and SERS (HPTLC-UV-SERS) method was developed and validated parallelly on the UV and SERS signals. To improve the repeatability of the SERS signal, several analytical conditions were optimized, so that direct quantitation with TLC-SERS was feasible without chemometric data extrapolation. The determination was done with UV scanning at 304 nm for HPTLC and with SERS signal at 1580 cm-1 (excitation 633 nm). The TLC-SERS method had a detection limit of 1.65 ng/spot, 95 times lower than HPTLC method (157 ng/spot). The HPTLC-UV-SERS method was applied on 24 real herbal samples collected from the market, among which 3 real samples were positive to sildenafil, and quantitation results by UV and SERS were in consistency. Not only this method was proved feasible for practical applications, but the recommendations for TLC-SERS procedures could also be useful in TLC-SERS method development for other compounds.

Doxycycline pharmacokinetics and tissue depletion in striped catfish (Pagasianodon hypophthalmus) after oral administration.

The pharmacokinetics and residue depletion of doxycycline (DOX) in striped catfish (Pagasianodon hypophthalmus) after oral dosage were investigated. The pharmacokinetic experiment was conducted in an aquarium, while the experiment of residue depletion was performed in both an aquarium and earth ponds. Medicated feed was administered orally using the gavage method at a dosage of 20 mg/kg body weight. Blood, liver, and kidney from medicated fish samples were collected. In the depletion experiments, fish were fed medicated feed for five consecutive days at a dosage of 20 mg/kg body weight, with samples collected during and after medication. The concentrations of DOX were quantified using an LC-MS/MS system. The pharmacokinetics parameters of DOX in striped catfish included the absorption rate constant (ka), absorption half-life (T1/2abs), maximal plasma concentration (Cmax), time to maximal plasma concentration (Tmax), and area under the plasma concentration-time curve from time 0 to 96 h (AUC0-96 h) which were 0.12 h-1, 5.68 h, 1123.45 ng/mL, 8.19 h, and 25,018 ng/mL/h, respectively. Residue depletion results indicated that the withdrawal times of DOX in muscle (with skin) from fish kept in the aquarium were slightly longer than that in fish raised in earth ponds, corresponding to 194 degree-days compared with 150 degree-days. In conclusion, administration of DOX at the dosage of 20 mg/kg body weight can be used for treatment of bacterial infections in striped catfish, and a withdrawal time of 5 days at 29.4°C will ensure consumer food safety due to the rapid depletion of DOX from muscle and skin.

Heptaellipside A, a rare new 2,28-bidesmosidic lupane-type saponin from the leaves of Heptapleurum ellipticum.

For the first time, phytochemical constituents of the leaves of Heptapleurum ellipticum were investigated. One rare new 2,28-bidesmosidic lupane-type saponin, named heptaellipside A (1), along with four other lupane-type analogs (2-5) were purified by combining differently chromatographic methods. All of the separated compounds (1-5) were communicated for the first time from H. ellipticum. The structures of them were definitely illustrated following extensive and comprehensive UV/VIS, FTIR, HRMS/ESI, and NMR techniques. Further, all isolated compounds were evaluated for their α-glucosidase and α-amylase inhibition. As the results, compound 3 respectively exhibited stronger in both inhibitory activities against α-glucosidase and α-amylase (IC50 values of 15.53 and 26.93 µM), than the acarbose standard (IC50 values of 214.50 and 143.48 µM).

La-doped MIL-88B(Fe)-NH2: a mixed-metal-organic framework photocatalyst for highly efficient reduction of Cr(vi) in an aqueous solution.

With the aim to resolve the problem of water pollution, we herein propose a new photocatalyst based on metal-organic frameworks (MOFs), called La-doped MIL-88B(Fe)-NH2 (MIL-88B((1 - x)Fe/xLa)-NH2), which was designed and employed for the photocatalytic reduction of Cr(vi) in aqueous solutions. MIL-88B((1-x)Fe/xLa)-NH2 materials with different x values were synthesized via a one-pot solvothermal method. Their characteristics were investigated using various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Brunauer-Emmett-Teller (BET) analysis, Fourier-transform infrared (FT-IR) spectroscopy and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). We found that compared to pristine MIL-88B(Fe)-NH2 with a photocatalytic efficiency of 67.08, MIL-88B((1 - x)Fe/xLa)-NH2 materials with x = 0.010, 0.025 and 0.050 exhibit excellent photocatalytic efficiencies reaching 88.21, 81.19 and 80.26%, respectively, after only 30 minutes of irradiation at a small catalyst dosage of 0.2 g L-1. These La-doped MIL-88B(Fe)-NH2 photocatalysts can work well under mild conditions (pH = 6). Furthermore, they are robust-can be recycled for at least four consecutive runs without any activity loss. This novel material is promising for the photocatalytic degradation of pollutants.

A study on the antioxidant, anti-inflammatory, and xanthine oxidase inhibitory activity of the Artemisia vulgaris L. extract and its fractions.

ETHNOPHARMACOLOGICAL RELEVANCE: Vietnamese people use mugwort (Artemisia vulgaris L.) to treat arthritis and gout. Our previous research shows that mugwort contains flavonoids, and its extract possesses antibacterial and anti-inflammatory activities. However, no publications have been on the xanthine oxidase inhibitory activity of mugwort and acute anti-inflammatory activity in vivo. AIM OF THE STUDY: The study aimed to verify the antioxidant, xanthine oxidase inhibitory, and anti-inflammatory capabilities of mugwort extract in vitro and in vivo, isolate phyto-compounds from potential bioactive fractions, and then evaluate their potential in inhibiting xanthine oxidase. METHODS: According to established methods, the extract and the active flavonoids were obtained using different chromatographic techniques. DPPH, ABTS, reducing power, and H2O2 elimination were used to evaluate antioxidant activity. The model of LPS-induced RAW264.7 cells was used to measure the inhibition of NO production. The carrageenan-induced paw oedema model was used to assess acute inflammation in mice. In vitro, xanthine oxidase inhibition assay was applied to investigate the effects of extract/compounds on uric acid production. Chemical structures were identified by spectral analysis. RESULTS: The assessment of the acute inflammatory model in mice revealed that both the 96% ethanol and the 50% ethanol extracts significantly decreased oedema in the mice's feet following carrageenan-induced inflammation. 96% ethanol extract exhibited a better reduction in oedema at the low dose. The analysis revealed that the ethyl acetate fraction had the highest levels of total polyphenols and flavonoids. Additionally, this fraction demonstrated significant antioxidant activity in various assays, such as DPPH, ABTS, reducing power, and H2O2 removal. Furthermore, it displayed the most potent inhibition of xanthine oxidase, an anti-inflammatory activity. Five phytochemicals were isolated and determined from the active fraction such as luteolin (1), rutin (2), apigenin (3), myricetin (4), and quercetin (5). Except for rutin, the other compounds demonstrated the ability to inhibit effective xanthine oxidase compared to standard (allopurinol). Moreover, quercetin (5) inhibited NO production (IC50 21.87 µM). CONCLUSION: The results indicate that extracts from A. vulgaris effectively suppressed the activity of xanthine oxidase and exhibited antioxidant and anti-inflammatory properties, potentially leading to a reduction in the production of uric acid in the body and eliminating ROS. The study identified mugwort extract and bioactive compounds derived from Artemisia vulgaris, specifically luteolin, apigenin, and quercetin, as promising xanthine oxidase inhibitors. These findings suggest that further development of these compounds is warranted. At the same time, the above results also strengthen the use of mugwort to treat gout disease in Vietnam.

Alternative TSS use is widespread in Cryptococcus fungi in response to environmental cues and regulated genome-wide by the transcription factor Tur1.

Alternative transcription start site (TSS) usage regulation has been identified as a major means of gene expression regulation in metazoans. However, in fungi, its impact remains elusive as its study has thus far been restricted to model yeasts. Here, we first re-analyzed TSS-seq data to define genuine TSS clusters in 2 species of pathogenic Cryptococcus. We identified 2 types of TSS clusters associated with specific DNA sequence motifs. Our analysis also revealed that alternative TSS usage regulation in response to environmental cues is widespread in Cryptococcus, altering gene expression and protein targeting. Importantly, we performed a forward genetic screen to identify a unique transcription factor (TF) named Tur1, which regulates alternative TSS (altTSS) usage genome-wide when cells switch from exponential phase to stationary phase. ChiP-Seq and DamID-Seq analyses suggest that at some loci, the role of Tur1 might be direct. Tur1 has been previously shown to be essential for virulence in C. neoformans. We demonstrated here that a tur1Δ mutant strain is more sensitive to superoxide stress and phagocytosed more efficiently by macrophages than the wild-type (WT) strain.

BASIC PENTACYSTEINE1 regulates ABI4 by modification of two histone marks H3K27me3 and H3ac during early seed development of Medicago truncatula.

Introduction: The production of highly vigorous seeds with high longevity is an important lever to increase crop production efficiency, but its acquisition during seed maturation is strongly influenced by the growth environment. Methods: An association rule learning approach discovered MtABI4, a known longevity regulator, as a gene with transcript levels associated with the environmentally-induced change in longevity. To understand the environmental sensitivity of MtABI4 transcription, Yeast One-Hybrid identified a class I BASIC PENTACYSTEINE (MtBPC1) transcription factor as a putative upstream regulator. Its role in the regulation of MtABI4 was further characterized. Results and discussion: Overexpression of MtBPC1 led to a modulation of MtABI4 transcripts and its downstream targets. We show that MtBPC1 represses MtABI4 transcription at the early stage of seed development through binding in the CT-rich motif in its promoter region. To achieve this, MtBPC1 interacts with SWINGER, a sub-unit of the PRC2 complex, and Sin3-associated peptide 18, a sub-unit of the Sin3-like deacetylation complex. Consistent with this, developmental and heat stress-induced changes in MtABI4 transcript levels correlated with H3K27me3 and H3ac enrichment in the MtABI4 promoter. Our finding reveals the importance of the combination of histone methylation and histone de-acetylation to silence MtABI4 at the early stage of seed development and during heat stress.

Management of a severe skeletal open bite case using temporary anchorage devices and multiloop edgewise arch wire technique.

The primary cause of complex AOB malocclusion is typically a combination of dental, skeletal, functional, and habitual factors. Open bite correction is a challenging treatment due to its complexity and the requirement for long-term stability, therefore, multidisciplinary treatment is often the best option for achieving stable esthetic outcomes.

Implementation of Telepharmacy to Provide Medication Consultation Service for Patients: A Case Study From Thu Duc City Hospital, Ho Chi Minh City.

Telepharmacy is receiving significant attention as an innovative approach. The objective of this study is to assess the needs and evaluate the impact of telepharmacy applications in drug consultations at Thu Duc City Hospital. We used a cross-sectional research design and conducted a survey with the participation of leaders of the Faculty of Pharmacy, clinical pharmacists, dispensing pharmacists, and patients or their caregivers who receive medication at the Pharmacy of Thu Duc Hospital. We deployed a telepharmacy application for consulting on drug use and surveyed the satisfaction of patients/family members with the telepharmacy model. 60.3% of survey subjects expressed a desire to receive drug use consultations through telepharmacy if the hospital were to offer this service. One hundred percent of the pharmacists at the pharmacy and the hospital's leadership believe that telepharmacy can address patient consultation needs and improve the current physical facilities in the dispensing area. Over 90% of telepharmacy users reported being satisfied or very satisfied with the service. Telepharmacy has garnered the attention of patients, their caregivers, and the medical staff at the Outpatient Pharmacy of Thu Duc Hospital. The majority of users are satisfied with the drug use consultation service provided by telepharmacy. By expanding the good results of Thu Duc Hospital to other hospitals, more patients across Vietnam can benefit from this innovative approach.

Simultaneous electrochemical determination of uric acid and hypoxanthine at a TiO2/graphene quantum dot-modified electrode.

A TiO2/graphene quantum dots composite (TiO2/GQDs) obtained by in situ synthesis of GQDs, derived from coffee grounds, and peroxo titanium complexes was used as electrode modifier in the simultaneous electrochemical determination of uric acid and hypoxanthine. The TiO2/GQDs material was characterized by photoluminescence, X-ray diffraction, Raman spectroscopy, high-resolution transmission electron microscopy, and energy-dispersive X-ray mapping. The TiO2/GQDs-GCE exhibits better electrochemical activity for uric acid and hypoxanthine than GQDs/GCE or TiO2/GCE in differential pulse voltammetry (DPV) measurements. Under optimized conditions, the calibration plots were linear in the range from 1.00 to 15.26 µM for both uric acid and hypoxanthine. The limits of detection of this method were 0.58 and 0.68 µM for uric acid and hypoxanthine, respectively. The proposed DPV method was employed to determine uric acid and hypoxanthine in urine samples with acceptable recovery rates.

Enhanced removal of pesticide micropollutant and bacteria using solar light-assisted Ag-doped TiO2: prospects for environmental and health impacts.

Pesticide micropollutants like 4-chlorophenol (4CP) and E. coli bacteria represent a substantial hazard, impacting both the environment and human health. This study delves into the effectiveness of Ag-doped TiO2 (Ag@TiO2) in removing both 4CP and E. coli. Ag@TiO2 has demonstrated remarkable effectiveness in removing 4CP under both solar and visible light conditions, earning degradation efficiencies of 91.3% and 72.8%, respectively. Additionally, it demonstrates outstanding photodegradation efficiency for 4CP (98.8%) at an initial concentration of 1 mg L-1. Moreover, Ag@TiO2 exhibited substantially higher removal performance for 4CP (81.6%) compared to TiO2 (27.6%) in wastewater. Analysis of the radicals present during the photodegradation process revealed that ·O2- primarily drives the decomposition of 4CP, with h+ and ·OH also playing significant roles in the oxidation reactions of the pollutant. Interestingly, even under dark conditions, Ag@TiO2 exhibited the capability to eliminate approximately 20% of E. coli, a percentage that increased to over 96% under solar light. In addition, the prospects for environmental and health impacts of utilizing Ag@TiO2 for pesticide micropollutant removal and bacteria were discussed.

Heterologous expression of pediocin PA-1 in Pichia pastoris: cloning, expression, characterization, and application in pork bologna preservation.

OBJECTIVE: Pediocin PA-1, an antimicrobial peptide derived from Pediococcus acidilactici PAC1.0, has a potential application as a food preservative thanks to its strong inhibitory activity against the foodborne pathogen L. monocytogenes. This study aimed to produce Pediocin PA-1 from the yeast P. pastoris and evaluate its characteristics. METHODS: Gene encoding Pediocin PA-1 was integrated into P. pastoris X33 genome to establish the strain X33::ped, which could produce and secrete this peptide into culture medium. The antimicrobial activity of Pediocin PA-1 was examined using agar diffusion assay. The stability of pediocin PA-1 was determined based on its remaining antibacterial activity after exposure to proteases and extreme pH and temperatures. The potential use of this bacteriocin in food preservation was demonstrated using the L. monocytogenes infected pork bologna. The anticancer activity of Pediocin PA-1 was also investigated on some cancer cells using MTT assay. RESULTS: We established the yeast P. pastoris X33::ped capable of producing pediocin PA-1 with antimicrobial activity against L. monocytogenes and some other harmful bacteria. Pediocin PA-1 was stable at 100˚C and resistant against pH 1-12 for 1 h, but susceptible to trypsin, α-chymotrypsin, and proteinase K. This peptide could reduce the number of L. monocytogenes in pork bologna by 3.59 log CFU/g after 7 days of storage at 4˚C. Finally, Pediocin PA-1 (25 µg/ml) inhibited the proliferation of A549 and Hela cancer cells. CONCLUSION: We succeeded in producing active Pediocin PA-1 from P. pastoris and demonstrated its potential use in food preservation and pharmaceutical industry.