Metagenomic Study on Chinese Homemade Paocai: The Effects of Raw Materials and Fermentation Periods on the Microbial Ecology and Volatile Components

“Chinese paocai” is typically made by fermenting red radish or cabbage with aged brine (6–8 w/w). This study aimed to reveal the effects of paocai raw materials on fermentation microorganisms by metagenomics sequencing technology, and on volatile organic compounds (VOCs) by gas chromatography–mass spectroscopy, using red radish or cabbage fermented for six rounds with aged brine. The results showed that in the same fermentation period, the microbial diversity in cabbage was higher than that in red radish. Secundilactobacillus paracollinoides and Furfurilactobacillus siliginis were the characteristic bacteria in red radish paocai, whereas 15 species of characteristic microbes were found in cabbage. Thirteen kinds of VOCs were different between the two raw materials and the correlation between the microorganisms and VOCs showed that cabbage paocai had stronger correlations than radish paocai for the most significant relationship between 4-isopropylbenzyl alcohol, α-cadinol, terpinolene and isobutyl phenylacetate. The results of this study provide a theoretical basis for understanding the microbiota and their relation to the characteristic flavors of the fermented paocai.

In Vitro Evidence on Bioaccessibility of Flavonols and Cinnamoyl Derivatives of Cruciferous Sprouts

Cruciferous sprouts are rising in popularity as a hallmark of healthy diets, partially because of their phytochemical composition, characterized by the presence of flavonols and cinnamates. However, to shed light on their biological activity, the ability to assimilate (poly)phenols from sprouts (bioaccessible fraction) during gastrointestinal digestion needs to be studied. In this frame, the present work studies the effect of the physicochemical and enzymatic characteristics of gastrointestinal digestion on flavonols and cinnamoyl derivatives, by a simulated static in vitro model, on different cruciferous (red radish, red cabbage, broccoli, and white mustard) sprouts. The results indicate that, although the initial concentrations of phenolic acids in red radish (64.25 mg/g fresh weight (fw)) are lower than in the other sprouts studied, their bioaccessibility after digestion is higher (90.40 mg/g fw), followed by red cabbage (72.52 mg/g fw), white mustard (58.72 mg/g fw), and broccoli (35.59 mg/g fw). These results indicate that the bioaccessibility of (poly)phenols is not exclusively associated with the initial concentration in the raw material, but that the physico-chemical properties of the food matrix, the presence of other additional molecules, and the specific characteristics of digestion are relevant factors in their assimilation.

Evidence on the Bioaccessibility of Glucosinolates and Breakdown Products of Cruciferous Sprouts by Simulated In Vitro Gastrointestinal Digestion

Cruciferous vegetables are gaining importance as nutritious and sustainable foods, rich in phytochemical compounds such as glucosinolates (GSLs). However, the breakdown products of these sulfur-based compounds, mainly represented by isothiocyanates (ITC) and indoles, can contribute to human health. In the human digestive system, the formation of these compounds continues to varying extents in the different stages of digestion, due to the contact of GSLs with different gastric fluids and enzymes under the physicochemical conditions of the gastrointestinal tract. Therefore, the aim of the present work was to uncover the effect of gastrointestinal digestion on the release of glucosinolates and their transformation into their bioactive counterparts by applying a simulated in vitro static model on a range of brassica (red radish, red cabbage, broccoli, and mustard) sprouts. In this sense, significantly higher bioaccessibility of ITC and indoles from GSLs of red cabbage sprouts was observed in comparison with broccoli, red radish, and mustard sprouts, due to the aliphatic GSLs proportion present in the different sprouts. This indicates that the bioaccessibility of GSLs from Brasicaceae sprouts is not exclusively associated with the initial content of these compounds in the plant material (almost negligible), but also with the release of GSLs and the ongoing breakdown reactions during the gastric and intestinal phases of digestion, respectively. Additionally, aliphatic GSLs provided higher bioaccessibility of their corresponding ITC in comparison to indolic and aromatic GSLs.

Physiological variation of irradiated red radish plants and their phylogenic relationship using SCoT and CDDP markers

Greenhouse experiment is carried out to explore the outcome of γ-radiation on physiological and genetic variation in red radish (Raphanus sativus) for two generations. Gamma rays from 60Co were used to penetrate red radish seeds with different dose levels (0.0, 10, 20, 40 and 80 Gy). Plants generated from irradiated seeds and from self-pollination of these plants, called M1 and M2 generations, respectively. Some morphological and physiological traits were then determined, and the genetic diversity of both generations was studied using Start Codon Targeted (SCoT) and Conserved DNA-Derived Polymorphism (CDDP) molecular markers. All studied morphological traits (number of leaves/plants, leave height, root diameter, and root weight) were steadily improved by raising irradiation dose rate, reaching a cumulative raise at the irradiation doe level 40 Gy and decreased at dose level 80 Gy. Photosynthetic pigments of red radish plants released a notable increase by increasing gamma rays dose level for chlorophyll (a), chlorophyll (b) and carotenoids for 40 Gy dose rate. Proline content was elevated proportionally to the irradiation dose level, with the greatest increase seen at dose level of 80 Gy. Moreover, phytochemical screening was detected for the both two generations. Fourteen SCoT primers generated a total number of banding patterns of 194 with average 13.86 and the primer SCoT-33 released the highest number banding patterns (21). The percentage mean of polymorphism for all the SCoT primers was 74.66% and was 66.49 and 63.74% for M1 and M2 respectively. Furthermore, fifteen CDDP primers generated a total number of banding patterns of 186 and the primer CDDP-5 relieved the highest number of banding patterns (20). The percentage mean of polymorphism for all the CDDP primers was 73.41% and was 64.38 and 65.91% for M1 and M2 respectively. It could be concluded that gamma irradiation exhibited an appropriate variation in red radish M1 and M2 which was detected by SCoT and CDDP molecular markers.

The Allelopathic Potential of Rosa blanda Aiton on Selected Wild-Growing Native and Cultivated Plants in Europe

Invasive plant species are responsible for changing colonized ecosystems by occupying new areas and creating a threat to the functioning of the native flora and fauna populations. Alien plants can produce allelochemicals, substances completely new to indigenous communities. This study investigated the germination seed reactions of Festuca rubra L. and Raphanus sativus L. var. radicula Pers. cv. Rowa on the extracts from the roots, stalks, leaves, and flowers of Rosa blanda. Aqueous extracts at concentrations of 1%, 2.5%, and 5% were used in order to determine the allelopathic potential of this alien rose for Europe. With the increase in the concentration of extracts, a decrease in the germination capacity of seeds of the tested species was observed. R. blanda extracts inhibited the growth of seedlings. Depending on the concentration and type of the extract, changes in biomass and water content in Red Fescue and Red Radish seedlings were also shown. The highest differences in the electrolyte leakages were noted in seedlings treated with 5% rose extracts. The study showed that the aqueous extracts of R. blanda leaves and flowers had the greatest allelopathic potential.

Development of Molecular Markers for Predicting Radish (Raphanus sativus) Flesh Color Based on Polymorphisms in the RsTT8 Gene

Red radish (Raphanus sativus L.) cultivars are a rich source of health-promoting anthocyanins and are considered a potential source of natural colorants used in the cosmetic industry. However, the development of red radish cultivars via conventional breeding is very difficult, given the unusual inheritance of the anthocyanin accumulation trait in radishes. Therefore, molecular markers linked with radish color are needed to facilitate radish breeding. Here, we characterized the RsTT8 gene isolated from four radish genotypes with different skin and flesh colors. Sequence analysis of RsTT8 revealed a large number of polymorphisms, including insertion/deletions (InDels), single nucleotide polymorphisms (SNPs), and simple sequence repeats (SSRs), between the red-fleshed and white-fleshed radish cultivars. To develop molecular markers on the basis of these polymorphisms for discriminating between radish genotypes with different colored flesh tissues, we designed four primer sets specific to the RsTT8 promoter, InDel, SSR, and WD40/acidic domain (WD/AD), and tested these primers on a diverse collection of radish lines. Except for the SSR-specific primer set, all primer sets successfully discriminated between red-fleshed and white-fleshed radish lines. Thus, we developed three molecular markers that can be efficiently used for breeding red-fleshed radish cultivars.

ANTI-CHOLOSETEROL ACTIVITIES OF WHITE (RAPHANUS RAPHANISTRUM) AND RED (RAPHANUS SATIVUS) RADISH ROOTS

Objective: The purpose of this research is to explore the in vitro activities of white (Raphanus raphanistrum) and red (Raphanus sativus) radish root ethanol extract in decreasing cholesterol levels. Methods: Ultrasonification method was used in obtaining 96% ethanol extract of white and red radish root. The cholesterol levels were analyzed by visible spectrophotometry, which was validated using Lieberman-Buchard reagents. The decreased cholesterol levels were converted into IC50 values. Results: The results showed that the IC50 of 96% white and red radish root ethanol extracts were 743.7 and 634.7 µg/ml, respectively. The results of statistical analysis using the T-test obtained a significant value greater than the probability value (P) of 0.05. Conclusion: Therefore, it was concluded that the activities of 96% ethanol extract of white and red radish roots did not have a significant ability to reduce the in vitro cholesterol levels.