The Potential of Medicinal Plants and Natural Products in the Treatment of Burns and Sunburn-A Review

Treating burns remains a challenge for modern medicine, especially in developing countries that cannot afford expensive, advanced therapies. This review article summarises clinical and animal model studies of botanical preparations and their mixtures in treating burn wounds and sunburn. Articles available in electronic databases such as PubMed, Scopus, Web of Science, Science Direct and Google Scholar, published in English in 2010-2022, were considered. In the described clinical trials, it was shown that some herbal preparations have better effectiveness in treating burn wounds, including shortening the healing time and reducing inflammation, than the conventional treatment used hitherto. These herbal preparations contained extracts from Albizia julibrissin, Alkanna tinctoria, Aloe vera, Arnebia euchroma, Betula pendula and Betula pubescens, Centella asiatica, Hippophaë rhamnoides, Juglans regia, Lawsonia inermis, and mixtures of Matricaria chamomilla and Rosa canina. Research on animal models shows that many extracts may potentially benefit the treatment of burn wounds and sunburn. Due to the diverse mechanism of action, antibacterial activity, the safety of use and cost-effectiveness, herbal preparations can compete with conventional treatment. The growing interest in alternative medicine and herbal medicine encourages further research. Not only single preparations but also their mixtures should be taken into account because the research conducted so far often suggests a synergistic effect of the ingredients.

Phytoprostanes, phytofurans, tocopherols, tocotrienols, carotenoids and free amino acids and biological potential of sea buckthorn juices

BACKGROUND

Juices are currently a fast-growing segment in the fruit and vegetable industry sector. However, there are still no reports on the diversity of the phytochemical profile and health-promoting properties of commercial sea buckthorn (Hippophaë rhamnoides) juices. This study aimed to identify and quantify phytoprostanes, phytofurans by ultra high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS), tocopherols, tocotrienols by ultra-performance liquid chromatography coupled with a fluorescence detector (UPLC-FL), carotenoids, and free amino acids by ultra-performance liquid chromatography coupled with a photodiode detector-quadrupole and tandem time-of-flight mass spectrometry (UPLC-PDA-Q/TOF-MS), and assess their anti-cholinergic, anti-diabetic, anti-obesity, anti-inflammatory, and antioxidant potential by in vitro assays of commercial sea buckthorn juices.

RESULTS

Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) in sea buckthorn juices were identified for the first time. Juices contained eight F₁ -, D₁ -, B₁ - and L₁ -phytoprostanes and one phytofuran (32.31-1523.51 ng and up to 101.47 μg/100 g dry weight (DW)), four tocopherol congeners (22.23-94.08 mg 100 g^-1 DW) and three tocotrienols (5.93-25.34 mg 100 g^-1 DW). Eighteen carotenoids were identified, including ten xanthophylls, seven carotenes and phytofluene, at a concentration of 133.65 to 839.89 mg 100 g^-1 DW. Among the 20 amino acids (175.92-1822.60 mg 100 g^-1 DW), asparagine was dominant, and essential and conditionally essential amino acids constituted 11 to 41% of the total. The anti-enzyme and antioxidant potential of juices correlated selectively with the composition.

CONCLUSION

Sea buckthorn juice can be a valuable dietary source of vitamins E and A, oxylipins and amino acids, used in the prevention of metabolic syndrome, inflammation, and neurodegenerative processes. The differentiation of the composition and the bioactive potential of commercial juices indicate that, for the consumer, it should be important to choose juices from the declared berry cultivars and crops. © 2021 Society of Chemical Industry.

NMR-based metabolomics approach on optimization of malolactic fermentation of sea buckthorn juice with Lactiplantibacillus plantarum

This work investigated the impact of malolactic fermentation on the metabolomic profile of sea buckthorn juice to optimize the fermentation process for flavor modification. Six strains of L. plantarum were used with varied pH of the juice, cell acclimation, and fermentation time. ¹H-NOESY spectra were acquired from fresh and fermented juices with a total of 46 metabolites identified. Less sugars and quinic acid were metabolized at pH 2.7 while oxidation of ascorbic acid was reduced at pH 3.5. l-Malic acid, essential amino acids, and nucleosides were consumed early during fermentation while sugars in general were consumed later in the fermentation. If deacidification is the main target of fermentation, strains that produce less acids and ferment less sugars, shorter fermentation time, and lower starter pH should be used. Higher starter pH and longer fermentation time promote formation of antimicrobial compounds and potentially increase antioxidant stability.

Role of Flavonols and Proanthocyanidins in the Sensory Quality of Sea Buckthorn (Hippophaë rhamnoides L.) Berries

Sensory profile, flavonols, proanthocyanidins, sugars, and organic acids were investigated in purees of six sea buckthorn (Hippophaë rhamnoides) cultivars. The sensory profiles of the purees were dominated by intense sourness followed by astringency and bitterness due to the high content of malic acid. Malic acid and isorhamnetin glycosides, especially isorhamnetin-3-O-sophoroside-7-O-rhamnoside, had close association with the astringent attributes in the different purees, whereas some of the known astringent compounds such as proanthocyanidin dimers and trimers or quercetin glycosides, had less impact. Moreover, the ratios between contents of acids and phenolic compounds were more important predictors of bitterness than the individual variables alone. Astringency and bitterness are important sensory factors for the consumer acceptance of sea buckthorn products. The current study provides new knowledge on the correlations between sensory properties and composition and supports industrial utilization of the sea buckthorn berries.

rhamnoides) Berries in Nordic Environment: Compositional Response to Latitude and Weather Conditions

Flavonol glycosides (FGs) in sea buckthorn (Hippophaë rhamnoides ssp. rhamnoides) berries of varieties 'Tytti' and 'Terhi', cultivated in northern Finland (68°02' N) for six years and southern Finland (60°23' N) for seven years, were investigated and compared by HPLC-DAD-ESI-MS/MS. The average total content of 23 identified glycosides of isorhamnetin and quercetin was 103 ± 23 and 110 ± 21 mg/100 g fresh berries in 'Terhi' and 'Tytti', respectively. The total contents of FGs, flavonol diglycosides, and triglycosides in both varieties were higher in the north than in the south, whereas total flavonol monoglycoside content behaved vice versa (p < 0.05). Among the 89 weather variables studied, the sum of the daily mean temperatures that are 5 °C or higher from the start of growth season until the day of harvest was the most important variable which associated negatively with the accumulation of FGs in berries. Such influence was much stronger in berries from the north than from the south.

Proanthocyanidins in Sea Buckthorn (Hippophaë rhamnoides L.) Berries of Different Origins with Special Reference to the Influence of Genetic Background and Growth Location

Wild sea buckthorn berries from Finland (Hippophaë rhamnoides ssp. rhamnoides) and China (ssp. sinensis) as well as berries of two varieties of ssp. rhamnoides cultivated in Finland and five of ssp. mongolica cultivated in Canada were compared on the basis of the content and composition of proanthocyanidins (PAs). Among all of the samples, only B-type PAs were found. The contents of dimeric, trimeric, tetrameric, and total PAs were in the range of 1.4-8.9, 1.3-9.5, 1.0-7.1, and 390-1940 mg/100 g of dry weight, respectively. The three subspecies were separated by three validated factors (R(2), 0.724; Q(2), 0.677) in the partial least squares discriminant analysis model. Significant differences in total PAs were found between the ssp. rhamnoides and mongolica samples (p < 0.05). In ssp. rhamnoides, samples grown in northern Finland were characterized by a high amount of total PAs, typically 2-3 times higher than that in the level found in southern Finland. In ssp. sinensis, altitude did not have a systematic effect on the PA composition, suggesting the significance of the interaction between genetic background and growth location.

Flavonol glycosides in berries of two major subspecies of sea buckthorn (Hippophaë rhamnoides L.) and influence of growth sites

Flavonol glycosides of wild sea buckthorn (Hippophaë rhamnoides ssp. sinensis) berries from China and cultivated berries (H. rhamnoides ssp. mongolica) from Finland and Canada were identified and quantified. Twenty-six flavonol glycosides were found with isorhamnetin and quercetin as the major aglycones. The contents of flavonol glycosides ranged 23-250 mg/100 g fresh berries and were significantly higher in the berries of ssp. sinensis than in those of ssp. mongolica. Among the cultivars of ssp. mongolica, the berries of 'Oranzhevaya' had the lowest (23 mg/100 g) content, and those of 'Prevoshodnaya' the highest content of flavonol glycosides (80 mg/100 g). Within the ssp. mongolica, the samples from Kittilä (Northern Finland) had higher levels of most flavonol glycosides than those from Turku (Southern Finland) and Québec. Among the ssp. sinensis berries of different growth sites, increasing trends were detected in the contents of most of the compounds as the altitude increased and as the latitude decreased. The wild berries (ssp. sinensis) from Sichuan had remarkably high contents and unique profiles of flavonol glycosides.

Capillary electrophoresis as a novel technique for screening natural flavonoids as kinase inhibitors

Capillary electrophoresis (CE) was used for the first time to evaluate the inhibition activity of aglycone flavonoids (such as quercetin and isorhamnetin) and some of their glycosylated derivatives toward human kinases. The cyclin-dependant kinase 5 (CDK5/p25) and the glycogen synthase kinase 3β (GSK3β) were chosen since they are very promising biological targets for developing treatments against neurodegenerative diseases and cancer. In a previous work, we developed an in-capillary kinase CE assay where the capillary was used as an enzymatic nanoreactor in which the kinase, its substrate, adenosine 5'-triphosphate (ATP) and its potential inhibitor were mixed by using transverse diffusion of laminar flow profiles (TDLFP). The product adenosine 5'-diphosphate (ADP) was then detected at 254nm and quantified. In this work, this assay was improved to reduce, for the first time, the dilution effect commonly observed with the TDLFP approach. Under the new conditions established herein, IC50 values for quercetin, kaempferol and flavopiridol were successfully obtained and were in the same order of magnitude of those reported in the literature using the conventional assay using radioactive (33)P-ATP. It was shown that aglycone flavonoids have an inhibition activity more important than their glycosylated derivatives. CE was also proved to be very efficient for evaluating inhibition activity of complex samples such as crude extracts of sea buckthorn (SBT) berries obtained by solvent-free microwave extraction (SFME). This novel approach to combine SFME technique to a CE-based enzymatic assay is very interesting for evaluating the biological activity of natural material in a fast, simple, economic (no use of neither fluorescent nor radiometric labels) and green (no organic solvents) manner.