Chemical composition of Prunus padus L. flower extract and its anti-inflammatory activities in primary bone marrow-derived macrophages

Photoprotective effect of topical treatment with Lopezia racemosa extract against deleterious UVB irradiation effects in the skin of hairless mice

Lopezia racemosa is known as a "mosquito flower or perlilla." It is commonly found in corn crops. In traditional Mexican medicine, this plant is used to treat stomach cancer and urinary tract infections. Likewise, compounds and extracts isolated from plants have shown cytotoxic and anti-inflammatory effects. The objective of this study was to evaluate the photochemoprotective effect of topical treatment with the methanolic extract of L. racemosa (MELR) as a photochemoprotective agent against the harmful effects of UV irradiation (UVR) on a bacterial model and hairless mice. The MELR components were separated and analyzed via HPLC-UV-ESI-MS. Antioxidant activity was evaluated by the ability of MERL to scavenge DPPH and ABTS free radicals and by its FRAP capacity. The toxicity of MELR was evaluated in keratinocyte cultures. The photoprotective capacity of MELR was assessed through challenge experiments using models with bacteria and hairless CD1 et/et mice; cytokines related to the damage caused by UVR were also measured. In the methanolic extract of L. racemosa, five metabolites were detected and identified: two isomers of quercetin 6-C glycoside, orientin, quercetin 3-(6″-acetylglycoside) and quercetin 3-(6″-galloylglycoside) 7-(2,3-dihydroxytetrahydro-2H-pyran-4-yl acetate). MELR exhibited DPPH and ABTS radical scavenging properties, in addition to Fe ion reducing activity. MELR showed a photoprotective effect against UVB radiation-induced death in Escherichia coli bacteria. At the histological level, topical treatment of CD-1 et/et mice with MERL reduced the damage caused by UVR. Quantification of interleukins in the blood of mice revealed that the expression of IL-12 was greater in the control group treated with ultraviolet radiation than in the group protected with MELR. The methanolic extract of L. racemosa has photochemoprotective properties.

Seasonal Variation in Plant Polyphenols and Related Bioactivities across Three Years in Ten Tree Species as Visualized by Mass Spectrometric Fingerprint Mapping

The currently changing climates and environments place plants under many types of stresses that affect both their survival and levels of chemical defenses. The gradual induction of defenses in stressed plant populations could be monitored on a yearly basis unless a seasonal and yearly variation in natural defense levels obscures such monitoring schemes. Here, we studied the stability of the species-specific polyphenol composition and content of 10 tree species over three growing seasons using five replicate trees per species. We specifically measured hydrolyzable tannins (galloyl and hexahydroxydiphenoyl derivatives), proanthocyanidins (procyanidins and prodelphinidins), flavonols (kaempferol, quercetin and kaempferol derivatives) and quinic acid derivatives with the group-specific UHPLC-DAD-MS/MS tool, together with two bioactivities, the protein precipitation capacity and oxidative activity. With the help of a fingerprint mapping tool, we found out that species differed a lot in their seasonal and between-year variation in polyphenols and that the variation was also partially specific to compound groups. Especially ellagitannins tended to have declining seasonal patterns while the opposite was true for proanthocyanidins. Some of the species showed minimal variation in all measured variables, while others showed even induced levels of certain polyphenol groups during the 3-year study. For every species, we found either species-specific baseline levels in qualitative and quantitative polyphenol chemistry or the compound groups with the most plasticity in their production. The used tools could thus form a good combination for future studies attempting to monitor the overall changes in polyphenol chemistry due to various biotic or abiotic stress factors in plant populations or in more controlled environments.

Provision of Ecosystem Services in Riparian Hemiboreal Forest Fixed-Width Buffers

The importance of riparian forest protection is widely acknowledged. However, scientific discussions are still ongoing as to the most suitable and effective protection activities for these forests. The quality of the provision of different ecosystem services in protected riparian forest buffers could provide an insight into the impact of protection regulations. Cultural ecosystem services in riparian forests have an important social-ecological context, especially with the growing interest in recreation activities in forests. The aim of our study was to compare provision of different ecosystem services in riparian forest buffers located both adjacent to (0–50 m) and distant from (51–200 m) the stream. In our study, four small-to-medium-sized rivers in Latvia were used. In total, six different indicators of ecosystem services were estimated, based on data from the National Forest Inventory and the European Soil Data Centre. Bayesian ordinal regression was employed to assess the differences between the two buffer strips. Our results showed that the majority of assessed ecosystem service indicators (Recreation potential of the forest ecosystem, Visual quality of the forest landscape, Potential for the presence of medicinal plants and Potential for the presence of nectar plants) were of higher quality in the adjacent (0–50 m) buffer. Only one indicator (Flora with phytoremediation potential) had significantly higher values in the distant buffer strips (estimate 0.24, CI: [0.11, 0.38]). The observed distribution of quality classes showed that, only for the indicator Potential of medicinal plants, the highest quality class was the most common (>60%), for other indicators dominated average quality class estimations. The obtained results suggested that the current protection status that riparian forest buffers have facilitated maintain the provision of several cultural and regulation & maintenance ecosystem services.

Fabrication and Characterization of Prochloraz Nanoemulsion against Penicillium citrinum for the Postharvest Storage of Navel Oranges

Nanoemulsions have become extremely popular water-insoluble pesticide delivery systems in recent years. In this study, prochloraz nanoemulsions were obtained by selecting the mixing ratio of surfactants (6:1, 3:1, 2:1, 1:1, 1:2, 1:3, and 1:6), surfactant concentration, and shearing time. The optimal formula was 10 wt % prochloraz, 6 wt % surfactant (2 wt % CO-100 + 4 wt % CO-360) dissolved in 6 wt % hydrocarbon solvent (S-100A), and deionized water replenished to 100 wt %. This formula meets the quality index standards of the Food and Agriculture Organization. Compared with oil-in-water emulsion (EW), the prochloraz nanoemulsion exhibited higher antifungal activity against Penicillium citrinum in vitro (lower LC₅₀ of 1.17 mg L^-1) and in vivo (fewer lesions). In addition, the L02 cells treated with the nanoemulsion had a higher survival rate and lower apoptosis rate at the same concentration. Results showed that the toxicity of the prochloraz nanoemulsion on L02 cells was lower than that of EW. The findings provide an important method for developing an efficient, safe, and environment-friendly nanoemulsion for postharvest fruit storage.

A Unique Acylated Flavonol Glycoside from Prunus persica (L.) var. Florida Prince: A New Solid Lipid Nanoparticle Cosmeceutical Formulation for Skincare

Polyphenols are known dietary antioxidants. They have recently attracted considerable interest in uses to prevent skin aging and hyperpigmentation resulting from solar UV-irradiation. Prunus persica (L.) leaves are considered by-products and were reported to have a remarkable antioxidant activity due to their high content of polyphenols. This study aimed at the development of a cosmeceutical anti-aging and skin whitening cream preparation using ethanol leaves extract of Prunus persica (L.) (PPEE) loaded in solid lipid nanoparticles (SLNs) to enhance the skin delivery. Chemical investigation of PPEE showed significantly high total phenolic and flavonoids content with notable antioxidant activities (DPPH, ABTS, and β-carotene assays). A unique acylated kaempferol glycoside with a rare structure, kaempferol 3-O-β-⁴C₁-(6″-O-3,4-dihydroxyphenylacetyl glucopyranoside) (KDPAG) was isolated for the first time and its structure fully elucidated. It represents the first example of acylation with 3,4-dihydroxyphenyl acetic acid in flavonoid chemistry. The in-vitro cytotoxicity studies against a human keratinocytes cell line revealed the non-toxicity of PPEE and PPEE-SLNs. Moreover, PPEE, PPEE-SLNs, and KDPAG showed good anti-elastase activity, comparable to that of N-(Methoxysuccinyl)-Ala-Ala-Pro-Val-chloromethyl ketone. Besides, PPEE-SLNs and KDPAG showed significantly (p < 0.001) higher anti-collagenase and anti-tyrosinase activities in comparison to EDTA and kojic acid, respectively. Different PPEE-SLNs cream formulae (2% and 5%) were evaluated for possible anti-wrinkle activity against UV-induced photoaging in a mouse model using a wrinkle scoring method and were shown to offer a highly significant protective effect against UV, as evidenced by tissue biomarkers (SOD) and histopathological studies. Thus, the current study demonstrates that Prunus persica leaf by-products provide an interesting, valuable resource for natural cosmetic ingredients. This provides related data for further studying the potential safe use of PPEE-SLNs in topical anti-aging cosmetic formulations with enhanced skin permeation properties.

Hyptis mociniana: phytochemical fingerprint and photochemoprotective effect against UV-B radiation-induced erythema and skin carcinogenesis

Skin cancer is a public health problem due to its high incidence. Ultraviolet radiation (UVR) is the main etiological agent of this disease. Photochemoprotection involves the use of substances to avoid damage caused by UV exposure. The aim of this work was to determine the phytochemical fingerprint and photochemoprotective effect against UVB radiation-induced skin damage such as erythema and carcinogenesis of H. mociniana methanolic extract (MEHm). The chemical composition of the MEHm was analysed by LC/ESI-MS/MS. Three quercetin derivatives, two pectinolides, and two caffeic acid derivatives were identified in the methanolic extract. MEHm has antioxidant effect and it is not cytotoxic in HaCaT cells. Phytochemicals from H. mociniana have a photochemopreventive effect because they absorb UV light and protect HaCaT cells from UVR-induced cell death. Also, in SKH-1 mice -acute exposure-, it decreased erythema formation, modulating the inflammatory response, reduced the skin damage according to histological analysis and diminished p53 expression. Finally, MEHm protects from photocarcinogenesis by reducing the incidence and multiplicity of skin carcinomas in SKH-1 mice exposed chronically to UVB radiation.