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Anaerobic bacteria and facultative anaerobe are usually used as delivery carriers of antitumor drugs because of their tumor hypoxia targeting and antitumor immune activation abilities, but suffer from dose-dependent systemic side effects. Here, engineered probiotics Nissle 1917 (EcN-T) were constructed for in-situ synthesis of melanin in tumor region for enhanced photothermal therapy (PTT) combining with immunotherapy. By means of genetic engineering, EcN-T that could highly express tyrosinase under near-infrared (NIR) light irradiation were constructed. Due to their intrinsic tumor hypoxia targeting, EcN-T could accumulate and rapidly proliferate in tumor region after intravenous injection. Tyrosinase expression for the following melanin biosynthesis within tumor could be initiated upon NIR exposure. Hyperbaric oxygen treatment facilitated the oxidation of tyrosine to promote the generation of melanin in situ, giving robust photothermal performance to induce immunogenic tumor cell death. Assited by immunostimulatory responses of EcN, maturation of dendritic cells and priming of cytotoxic T cells were largely promoted in tumor tissue, resulting in significant inhibition of tumor growth and recurrence. This bacteria-mediated combined therapeutic strategy showed high efficacy and good safety. By means of genetic engineering and synthetic biology, engineered probiotics Nissle 1917 (EcN-T) which show excellent tumor targeting and proliferation abilities are constructed for in-situ synthesis of melanin in tumor region induced by NIR light irradiation and HBO treating. Upon light exposure, considerable heat can be generated to induce immunogenic tumor cell death. Assited by immunostimulatory responses of EcN, maturation of dendritic cells and priming of cytotoxic T cells are largely promoted in tumor tissue, giving significant inhibition of tumor growth and recurrence. [Display omitted] • Engineered probiotics Nissle 1917 can intracellularly produce melanin with excellent photothermal performance. • Engineered probiotics Nissle 1917 can rapidly proliferate and homogenously distribute in tumor region. • Melanin biosynthesis within tumor can be initiated upon external NIR exposure. • Hyperbaric oxygen can promote the generation of melanin within tumor. [ABSTRACT FROM AUTHOR]

[Display omitted] • Components of Chrysanthemum morifolium cv. Fubaiju essential oil (CMF-EO) were characterized. • CMF-EO showed excellent antifungal activities against six common fungus. • Antifungal targets were cell membrane, mitochondrial membrane, and DNA. • Multiple antifungal mechanisms make fungi difficult to develop drug resistance. Chrysanthemum morifolium cv. Fubaiju (CMF) has been used as a dietary herb in East Asia for centuries. The chemical composition and antifungal activity of CMF essential oil (CMF-EO) were investigated in this study. We have found that CMF-EO was a light-yellow, transparent liquid (0.61% yield, w/w) and majorly contain 31 volatile components with a total of 98.41% determined by GS and GC/MS. Camphor was the major compound (16.87%), followed by 1,8-cineole (10.62%), β -curcumene (9.51%), bornyl acetate (7.43%), α -zingiberene (6.97%), β-elemene (6.47%), α -bisabolol (4.74%), borneol (4.24%) and eugenol (4.23%). In addition, contents with more than 2% of the total CMF-EO were 1-caryophyllene (3.92%), chrysanthenyl acetate (3.29%), caryophyllene oxide (2.28%), and chamazulene (2.23%). Six fungal strains were used to study the antifungal activities and mechanisms of CMF-EO using fluorescence probe–membrane integrity assay, analysis of cytoplasmic membrane permeability, electron microscopy, monitoring of the effect of the mitochondrial membrane potential and DNA binding assay. CMF-EO effectively inhibited the growth of C. albicans , C. glabrata , C. tropicalis , S. cerevisiae , D. hansenii , and Z. parabailii with minimum inhibition concentrations of 31.25, 31.25, 62.5, 31.25, 15.625, and 15.625 μg/mL, respectively, and minimum fungicidal concentrations of 62.5, 125.0, 125.0, 62.5, 31.25, and 62.5 μg/mL, respectively. The elucidated antifungal mechanisms of CMF-EO included the destruction of cytoplasmic membrane and the damage of mitochondria and DNA. The multiple antifungal mechanisms made it difficult for fungi to develop drug resistance, and this finding might shed new light on the development of new fungal agents. [ABSTRACT FROM AUTHOR]

• The dominant components of the essential oil from Atractylodes lancea (Thunb.) DC. were β-eudesmol and hinesol. • The essential oil showed an excellent antioxidant activity correlated well with increasing dose in vitro and in vivo. • The essential oil showed a wide antibiogram against both Gram-positive and Gram-negative bacteria. • The antibacterial target of the essential oil was cell membrane. Atractylodes lancea (Thunb.) DC. is an important traditional herb used eastern Asia in folks for centuries. The antioxidant and antibacterial activities of Atractylodes lancea essential oil were investigated. An essential oil was extracted by steam distillation method from rhizomes of Atractylodes lancea. Chemical components of the essential oil were determined by gas chromatography-mass spectrometry. Antioxidant activities of the essential oil were investigated by DPPH− radical scavenging, inhibition of lipid peroxidation, and effect on the total antioxidant capacity in mice. Antimicrobial activities of the essential oil were determined by agar disc diffusion assay and double-broth dilution method. Antimicrobial mechanisms were investigated based on cell membrane permeability, fluorescence probe-membrane integrity assay, and electron microscopy. The results showed that the essential oil was composed of β-eudesmol (36.5 %), hinesol (29.4 %), elemol (4.21 %), and atractylone (4.10 %). The essential oil showed antioxidant activities in vitro and in vivo , and exhibited antibacterial activities against both Gram-positive and Gram-negative bacteria. The antibacterial mechanism of the essential oil involved the simultaneous disruption of the cell membrane. Therefore, Atractylodes lancea essential oil might be considered as a natural antioxidant and antibacterial agent with potential application in food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]