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Background: A common health condition among older persons is xerosis cutis. Topical corticosteroid treatments are ­associated with side effects. There is an unmet need for her­bal treatment alternatives. Coccinia grandis, Clerodendrum inerme and Acanthus ebracteatus are used to treat skin con­ditions in Thai traditional medicine. This study aimed to investigate their antimicrobial and antioxidant properties, synergistic properties as well as their cytotoxicity. Methods: ­Ethanolic herbal extracts were used to perform minimal ­inhibitory (MIC) and minimal bactericidal concentration (MBC) assays on common skin pathogens. Synergistic anti­microbial activity was evaluated by a chequerboard assay. Antioxidant and synergistic properties were assessed by a 1,1-diphenyl-2-picrylhydrazyl assay. Cytotoxicity was tested on normal adult human primary epidermal keratinocytes. Results: All extracts showed an inhibitory effect on growth of all microorganisms tested. MIC and MBC values ranged from 0.0625 to 32 mg/mL and from 0.0625 to >256 mg/mL, respectively. A. ebracteatus extract markedly demonstrated bactericidal activity against an methicillin-resistant Staphylococcus aureus strain. Additive antimicrobial activity was observed (fractional inhibitory concentration index values: 0.75–1). All extracts possessed antioxidant properties (IC50 values: 0.12–0.25 mg/L). However, antagonism was observed with paired extract combinations (combination index values: 1.025–1.455). The cell viability assay confirmed that herbal extracts were not cytotoxic. Conclusions: Our results provide early findings of pharmacological activities to support a novel choice of herbal combinations as potential local skin treatment options for xerosis cutis.

Background Cuminum cyminum L., commonly known as cumin, has been traditionally used in Thai traditional medicine and traditional food flavoring. The present study investigated the chemical composition, antimicrobial activity against all tested major food-borne pathogenic bacteria, and bioactive components of essential oil extracted from C. cyminum L. collected in Thailand. Methods The main components of the essential oil were investigated by gas chromatography–mass spectrometry (GC-MS) technique. Antibacterial activities against Bacillus cereus, Staphylococcus aureus, Escherichia coli, and Salmonella Typhi were investigated by disk diffusion and microdilution method. The presence of the biologically active antibacterial components was also confirmed by the thin-layer chromatography (TLC)-bioautography. Results The main components of the essential oil investigated by GC-MS were cuminaldehyde (27.10%), beta-pinene (25.04%) and gamma-terpinene (15.68%). The essential oil exhibited antibacterial activity against B. cereus, S. aureus, E. coli and S. Typhi. The essential oil showed the strongest antimicrobial activity against B. cereus with a comparable inhibition zone to tetracycline. TLC confirmed the presence of biologically active antibacterial component in the essential oil against all tested food-borne bacteria. It is further demonstrated that cuminaldehyde was the most active compound in TLC-bioautography which inhibited all of tested bacteria. Conclusions Essential oil extracted from C. cyminum L. exhibited antibacterial activity against all tested major food-borne pathogenic bacteria. Cuminaldehyde is a major bioactive component. Our results suggest that the essential oil extracted from C. cyminum L. could be applied as an alternative natural preservative to control food-borne disease and have the potential for further development of new antibacterial agents.

Background: Zanthoxylum rhetsa (Roxb.) DC and Zanthoxylum limonella Alston are spices for flavouring in indigenous Thai food. They are traditionally used as an aromatic, astringent, antimicrobial, antiseptic and antidiabetic agent. The purpose of this study is to examine their chemical compositions and evaluate antibacterial, antioxidant and anticancer properties of the essential oils.Materials and Methods: The essential oils of Z. rhetsa and Z. limonella were analysed for phytochemical constituents by Gas chromatography–mass spectrometry (GC-MS). The antibacterial activity was determined against several bacteria using the microdilution method. Antioxidant capacity was determined by free radical scavenger 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) methods. The anticancer activity was determined with two breast cancer cell lines (MCF-7 and MDA-MB-231) and the normal African green monkey kidney epithelial (Vero) cell line and using MTT assay.Results: Sabinene (22.51%) and terpinene-4-ol (32.33%) were found to be major components of Z. rhetsa essential oil while limonene (57.94%) and alpha-phelladrene (15.54%) were the major components of Z. limonella essential oil. Essential oil from Z. limonella exhibited broad spectrum antibacterial activity. Z. rhetsa and Z. limonella essential oils exhibited moderate antioxidant activity. The essential oil from Z. rhetsa possessed the ability to inhibit breast cancer cell (MCF-7 and MDA-MB-231) proliferation and cell viability.Conclusion: This study suggest that the essential oils from Z. limonella and Z. rhetsa could be applied as safe antibacterial and antioxidant agents for food and have the potential for further development of new anticancer agents.Keywords: Zanthoxylum rhetsa, Zanthoxylum limonella, GC-MS, antibacterial activity, antioxidant activity, anti-breast cancer activity

Multilocus sequence typing analysis of Streptococcus uberis has identified a cluster of isolates associated with clinical and subclinical mastitis and a cluster associated with cows with low somatic cell counts in their milk. Specific groups of genotypes (global clonal complex [GCC] sequence type 5s [ST5s] and GCC ST143s) were highly associated ( P = 0.006) with clinical and subclinical mastitis and may represent a lineage of virulent isolates, whereas isolates belonging to GCC ST86 were associated with low-cell-count cows. This study has, for the first time, demonstrated the occurrence of identical sequence types (ST60 and ST184) between different continents (Australasia and Europe) and different countries (Australia and New Zealand). The standardized index of association and the empirical estimation of the rate of recombination showed substantial recombination within the S. uberis population in Australia, consistent with previous multilocus sequence type analyses.