A new plant-based probiotic from juá: Source of phenolics, fibers and antioxidant properties.

The objective of this study was to evaluate the viability of juá pulp for fermentation by monoculture L. casei (Lc - 01) and L. acidophilus (La - 05) and co-culture (25 and 37 °C) for 72 h. Viable strain values (> 7 log CFU/g), pH reduction (below 3.7), fructose and glucose and increased of lactic acid showed that the pulp of juá served as a good matrix for fermentation. Catechin, epicatechin, epigallocatechin procyanidin B1, and gallic acid were the main phenolics that contributed to antioxidant activity. Fermentation by mono or co-culture increased or reduced the content of phenolics and antioxidant activity. Results showed that culture, time and temperature have effects in the fermentation of juá pulp. The co-cultivation of La - 05 + Lc - 01 contributed to improving the bioaccessibility of gallic acid (72.9%) of the jua pulp. Finding indicate juá pulp as a promising substrate to obtaining a new probiotic plant-based fermented beverage.

Calotropis procera (L.) mediated synthesis of AgNPs and their application to control leaf spot of Hibiscus rosa-sinensis (L.).

Nature is gifted with a wide range of ornamental plants, which beautify and clean the nature. Due to its great aesthetic value, there is a need to protect these plants from a variety of biotic and abiotic stresses. Hibiscus rosa-sinensis (L.) is an ornamental plant and it is commonly known as China rose or shoeblack plant. It is affected by several fungal and bacterial pathogens. Current study was designed to isolate leaf spot pathogen of H. rosa-sinensis and its control using silver nanoparticles (AgNPs). Based on molecular and morphological features, the isolated leaf spot pathogen was identified as Aspergillus niger. AgNPs were synthesized in the leaf extract of Calotropis procera and characterized. UV-vis spectral analysis displayed discrete plasmon resonance bands on the surface of synthesized AgNPs, depicting the presence of aromatic amino acids. Fourier transform infrared spectroscopy (FTIR) described the presence of C-O, NH, C-H, and O-H functional groups, which act as stabilizing and reducing molecules. X-ray diffraction (XRD) revealed the average size (~32.43 nm) of AgNPs and scanning electron microscopy (SEM) depicted their spherical nature. In this study, in vitro and in vivo antifungal activity of AgNPs was investigated. In vitro antifungal activity analysis revealed the highest growth inhibition of mycelia (87%) at 1.0 mg/ml concentration of AgNPs. The same concentration of AgNPs tremendously inhibited the spread of disease on infected leaves of H. rosa-sinensis. These results demonstrated significant disease control ability of AgNPs and suggested their use on different ornamental plants.

Disaccharide anthocyanin delphinidin 3-O-sambubioside from Hibiscus sabdariffa L.: Candida antarctica lipase B-catalyzed fatty acid acylation and study of its color properties.

Enzymatic lipophilization is an important process to extend the use of anthocyanins in lipidic media. In this work delphinidin 3-O-sambubioside (Dp3sam) isolated from Hibiscus sabdariffa L. flower was esterified with octanoic acid using Candida antarctica lipase B. The physical-chemical properties of the new lipophilic pigment were studied by UV-vis spectroscopy. Dp3sam with chloride, acetate and formate as counter ions were employed to study the lipophilization reaction. The hydrolysis of the reagent was avoided with a formate counter ion and the expected product was achieved with a noteworthy change of solubility. 1D and 2D NMR characterization of Dp3sam-C8 confirmed that the lipophilization took place at the primary alcohol of the glucoside moiety. Overall, the Dp3sam-C8 ester presents a stabilization of the quinoidal base (blue color) at neutral or moderate alkaline pH, which foresees a potential use of this pigment as a broad kind of industries on lipo-soluble formulations.

Anthocyanin Induction by Drought Stress in the Calyx of Roselle Cultivars.

Abiotic factors can alter the chemical profile of crops and the number of compounds they contain. In this study, the anthocyanin and anthocyanidin contents, determined by ultra-performance liquid chromatography (UPLC-MS/MS), and the colour attributes of the calyces of three cultivars of Hibiscus sabdariffa subjected to three water stress regimes during the stage of physiological maturity were investigated. The total anthocyanin content in calyx increased relative to the control content under a 65% moisture irrigation regime. Among the cultivars, UAN16-2 showed the greatest increases in the contents of cyanidin, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside, and cyanidin 3-O-sambubioside. The content of cyanidin 3-O-sambubioside showed the greatest increase, increasing by 55% relative to the control level. The contents of these compounds are correlated with colour attributes such as luminosity. Water stress under the 33% moisture condition during plant development led to decreased anthocyanin contents in all of the roselle cultivars.

Antibacterial effect of roselle extracts (Hibiscus sabadariffa), sodium hypochlorite and acetic acid against multidrug-resistant Salmonella strains isolated from tomatoes.

UNLABELLED: Antibiotic-resistant Salmonella strains were isolated from saladette and red round type tomatoes, and an analysis done of the antibacterial activity of roselle calyx extracts against any of the identified strains. One hundred saladette tomato samples and 100 red round tomato samples were collected from public markets. Each sample consisted of four whole tomatoes. Salmonella was isolated from the samples by conventional culture procedure. Susceptibility to 16 antibiotics was tested for the isolated Salmonella strains by standard test. The antibacterial effect of four roselle calyx extracts (water, methanol, acetone and ethyl acetate), sodium hypochlorite and acetic acid against antibiotic-resistant Salmonella isolates was evaluated on contaminated tomatoes. Twenty-four Salmonella strains were isolated from 12% of each tomato type. Identified Salmonella serotypes were Typhimurium and Typhi. All isolated strains exhibited resistance to at least three antibiotics and some to as many as 12. Over contaminated tomatoes, the roselle calyx extracts produced a greater reduction (2-2·6 log) in antibiotic-resistant Salmonella strain concentration than sodium hypochlorite and acetic acid. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of multidrug-resistant Salmonella in vegetables is a significant public health concern. Multidrug-resistant Salmonella strains were isolated from raw tomatoes purchased in public markets in Mexico and challenged with roselle Hibiscus sabdariffa calyx extracts, sodium hypochlorite and acetic acid. On tomatoes, the extracts caused a greater reduction in the concentration of antibiotic-resistant Salmonella strains than sodium hypochlorite and acetic acid. Roselle calyx extracts are a potentially useful addition to disinfection procedures of raw tomatoes in the field, processing plants, restaurants and homes.

Effects of consuming diets containing Agave tequilana dietary fibre and jamaica calyces on body weight gain and redox status in hypercholesterolemic rats.

Dietary fibre (DF) obtained from Agave tequilana, which is rich in fructans and insoluble DF, and jamaica calyces (Hibiscus sabdariffa), which is rich in DF and phenolic compounds, were assessed as new potential functional ingredients using the hypercholesterolemic animal model. Wistar rats (200-250 g) were divided into 3 groups (n=8) and fed with cholesterol-rich diets supplemented with cellulose (CC, control), agave DF (ADF) or ADF with jamaica calyces (ADF-JC). After consuming the test diets for 5 weeks, weight gain in the ADF-JC group was significantly lower than in the other groups. The ADF and ADF-JC groups had a reduced concentration of cholesterol transporters in the caecum tissue, although no changes were observed in the plasma lipid profile. Both treatments improved the redox status by reducing the malondialdehyde serum levels and protein oxidative damage, compared to the CC group. DF from A. tequilana alone, or in combination with jamaica calyces, shows promising potential as a bioactive ingredient.