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Supplemental material, sj-docx-1-jdr-10.1177_00220345231164111 for Mucoadhesive Vaccine Delivery Systems for the Oral Mucosa by K. Mokabari, M. Iriti and E.M. Varoni in Journal of Dental Research

Plants belonging to the genus Allium are widely cultivated and used all over the world as food and medicinal plants. Since ancient times, these plants, particularly garlic (Allium sativum L.) and onion (Allium cepa L.), have represented important components of typical recipes and traditional healing systems. Not the least of which, their use as food biopreservatives is well documented, due to the relevant antibacterial activity of their extracts and essential oils. In addition to garlic and onion, this review article deals with the main members of the genus Allium, including A. ampeloprasum (Leek), A. schoenoprasum (Chive) and A. ascalonicum (Shallot), focusing both on their ethnonutritional uses and potential as promising food biopreservative agents. Noteworthy, recent research has demonstrated Allium derivatives to be novel components in active edible coatings as well as nanoformulates.

In this study, we evaluated the effects of the extracts of the leaves of species from the Rubiaceae (Galium aparine L. and Asperula arvensis L.), Fabaceae (Lathyrus aphaca L. and Vicia narbonensis L.) and Poaceae (Digitaria sanguinalis (L.) Scop. and Hordeum murinum L.) plant families on a wide and extensive panel of isolated methicillin-resistant Staphylococcus aureus strains (MRSA). The effects of the methanolic leaf extracts of Rubiaceae, Fabaceae and Poaceae plants on MRSA were evaluated by the disc diffusion assay and the broth dilution method. Among a total of 177 S. aureus isolates, 92 (51.97%) were found to be methicillin-resistant in an antibiogram and this was confirmed by the presence of the mecA gene in polymerase chain reaction method. All MRSA isolates were sensitive to all extracts. There were dose-dependent inhibitions on tested microorganisms for all plant extracts which showed maximum inhibition zones at a concentration of 300 mg/L. L. aphaca, G. aparine and H. murinum exhibited the highest antibacterial activity on the MRSA strains compared to the positive control (P0.05), as well as higher total polyphenol and flavonoid contents than other plant extracts. Minimum inhibitory concentrations on MRSA isolates ranged from 388.4 ± 0.2 mg/L, in D. sanguinalis, to 5.5 ± 0.1 mg/L, in L. aphaca. The methanolic extracts of L. aphaca (Fabaceae), G. aparine (Rubiaceae), and H. murinum (Poaceae) proved to have high antibacterial activity on MRSA isolates, thus representing promising antimicrobial agents in clinical settings.

Infrared thermography can be used as a tool for evaluating antitranspirant treatment through the measurement of evaporative fluxes. The aim of this work is to compare the leaf surface temperatures of plant treated with chitosan (CHT), a potential stomatal-closing antitranspirant, with temperatures of leaves treated with the commercially available antitranspirant Vapor Gard , a film-forming polyterpene. The main problem in the correct evaluation of stomatal conductance at leaf level is due to the need of performing a measurement in a completely non-invasive method. The main advantage of thermographic method is the possibility to acquire information about instantaneous conditions of transpiration over a large number of plants, with no need of sampling and avoiding any contact with plants. Tests on bean plants (Phaseolus vulgaris) showed the applicability of the thermal imaging to discriminate plants with different evaporation rate due to treatment with different antitranspirant compounds. Quantitative evaluation of evaporative flux and stomatal conductance was obtained through reference measurements on standards with calibrated conductance. Non-destructive gravimetric measurements were used in order to get a reliable evaluation of evaporative fluxes. In conclusion, thermographic approach, in climatic chamber, seems to be a valid tool for rapidly screening the performance of different antitranspirant products.

The cytopathology of a Potato virus X (PVX) recombinant variant (encoding as fusion of an epitope of immunological interest with the N-terminus of the coat protein, PVX Sma P18DD) has been compared with that induced by the wild-type virus (PVX wt) in Nicotiana benthamiana plants. Both PVX wt and PVX Sma P18DD caused similar ultrastructural alterations, characterized by the presence of laminated inclusion components and bulk virus accumulations in mesophyll cells. However, some striking differences were observed not only in the morphology of these accumulations (typically ordered in PVX wt infection and disordered in PVX Sma P18DD infection) but also because the chimeric virus caused peculiar alterations in chloroplasts structure.

Chitosan (CHT) is a natural compound able to activate the plant own defence machinery against pathogen attacks and to reduce both transpiration and stomatal opening when applied as foliar spray. The data here reported show that CHT-induced antitranspirant activity in bean plants is mediated by ABA, whose level raised over threefold in treated leaves, 24 h after foliar spraying. This is thought to induce partial stomatal closure via a H2O2-mediated process, as confirmed by scanning electron microscopy (SEM) and histocytochemistry, and, in turn, a decrease of stomatal conductance to water vapor (Gw) and transpiration rate (E), assessed by gas exchange measurements. The relatively high internal CO2 concentration (Ci) values, suggest the occurrence of a slight decrease in carboxylation efficiency after CHT treatment, which however did not prevail over stomatal limitations. The intrinsicwater use efficiency(WUEi) of CHT treated plants was not statistically different from controls and the maximal photochemical efficiency (Fv/Fm) of PSII was not affected. Moreover, CHT determined a stimulation of the xanthophyll cycle towards deepoxidation state. On the whole, these results, besides confirming the effectiveness of CHT in reducing plant transpiration, prove that the mechanism underlying this activity differs from that showed by the commercial antitranspirant Vapor Gard® (VP). In fact, the efficacy of the latter is based on the formation of a thin antitranspirant film over the leaf and not on the reduction of stomatal opening. Finally, suggestions for possible use of the two antitranspirants in different environmental conditions are discussed.

In this study we investigated the acute exposure of the aquatic macrophyte Callitriche obtusangula to the herbicide oxadiazon (Ronstar_). The toxic effects on C. obtusangula were evaluated, 24 h after exposure, by assessing visible necrotic leaf lesions and, 12 h after exposure, via analyses of dead cells and hydrogen peroxide (H2O2) deposits localized by histocytochemical analysis with Trypan blue and 3,30-diaminobenzidine (DAB), respectively. As a result, we found that 0.1275 ¼g L-1 a.i. (active ingredient) oxadiazon was the maximum concentration that produced no observable adverse effects (NOAEC) both at leaf and tissue levels, at any considered exposure time. Additionally, we assayed the protective effect of pre-treatment with 0.25 mM N-acetylcysteine (NAC), a cysteine donor, on the damage caused by the toxic herbicidal dose of 6.37 ¼g L-1 a.i to C. obtusangula, correlating the NAC observed protection to the direct H2O2-scavenging and to the enhancement of glutathione parameters. NAC-treated plants showed a fourfold increase in the GSH (reduced glutathione) + GSSG (oxidised glutathione) content (149.2 nmol g-1 FW) compared to controls (36.1 nmol g-1 FW); in the NAC + oxadiazon treatments, the GSH + GSSG content was more than fivefold higher (202.1 nmol g-1 FW). GSH showed a similar trend in NAC and NAC + oxadiazon treatments, being six- (130.0 nmol g-1 FW) and eightfold (185.0 nmol g-1 FW) higher, respectively, compared to controls (20.7 nmol g-1 FW). Accordingly, the GSH/GSSG ratio in NAC- and NAC + oxadiazon-treated plants was significantly increased compared to controls, indicating alleviation of oxidative stress.

Stolbur phytoplasma infection has been reported, for the first time, in a new host, Solanum malacoxylon, growing in the Botanical Garden of Milan University. This shrub, native of South America, synthesizes vitamin D compounds, important for biomedical and biotechnological purposes. Pathogen detection was performed by light and transmission electron microscopy, and confirmed by molecular diagnosis, based on PCR and restriction fragment length polymorphic (RFLP) analysis of the phytoplasmal 16S rRNA and tuf genes. By means of enzymatic restriction and phylogenetic analysis on these genes, it was found that the phytoplasma belongs to the Stolbur group, taxonomic subgroup 16SrXII-A, thus indicating S. malacoxylon as an additional host for this pathogen. Solanum malacoxylon could be then involved in the natural Stolbur phytoplasma spreading throughout South American areas, where this wild plant grows endemically. © 2007 The Authors.

Stolbur phytoplasma infection has been reported, for the first time, in a new host, Solanum malacoxylon, growing in the Botanical Garden of Milan University. This shrub, native of South America, synthesizes vitamin D compounds, important for biomedical and biotechnological purposes. Pathogen detection was performed by light and transmission electron microscopy, and confirmed by molecular diagnosis, based on PCR and restriction fragment length polymorphic (RFLP) analysis of the phytoplasmal 16S rRNA and tuf genes. By means of enzymatic restriction and phylogenetic analysis on these genes, it was found that the phytoplasma belongs to the Stolbur group, taxonomic subgroup 16SrXII-A, thus indicating S. malacoxylon as an additional host for this pathogen. Solanum malacoxylon could be then involved in the natural Stolbur phytoplasma spreading throughout South American areas, where this wild plant grows endemically.