Antimicrobial, Antigenotoxicity, and Characterization of Calotropis procera and Its Rhizosphere-Inhabiting Actinobacteria: In Vitro and In Vivo Studies.

Calotropis procera (C. procera) is a wild shrub that is a medicinal plant found in abundance throughout Saudi Arabia. In this study, we investigated the phytochemical composition and antigenotoxic properties of the ethanolic extract of C. procera, in addition to the antimicrobial activity of the plant and its rhizospheric actinobacteria effects against pathogenic microorganisms. Soil-extract medium supplemented with glycerol as a carbon source and starch-casein agar medium was used for isolation of actinobacteria from rhizosphere. From the plant, a total of 31 compounds were identified using gas chromatography/mass spectrometry (GC-MS). The main components were α-amyrin (39.36%), lupeol acetate (17.94%), phytol (13.32%), hexadecanoic acid (5.55%), stigmasterol (3.16%), linolenic acid (3.04%), and gombasterol A (2.14%). C. procera plant extract's antimicrobial activity was investigated using an agar well-diffusion assay and minimum inhibitory concentration (MIC) against six pathogenic microbial strains. The plant extract of C. procera was considered significantly active against Staphylococcus aureus, Klebsiella pneumonia, and Escherichia coli, with inhibition zones of 18.66 mm, 21.26 mm, and 21.93 mm, respectively. The plant extract was considered to be a moderate inhibitor against Bacillus subtilis, with MIC ranging from 0.60-1.50 mg/mL. On the other hand, the isolated actinobacteria were considered to be a moderate inhibitor against S. aureus (MIC of 86 µg/mL), and a potent inhibitor, strain CALT_2, against Candida albicans (MIC of 35 µg/mL). The 16S rRNA gene sequence analysis showed that the potential strains belonged to the genus Streptomyces. The effect of C. procera extract against cyclophosphamide (CP)-induced genotoxicity was examined by evaluating chromosome abnormalities in mouse somatic cells and DNA fragmentation assays. The current study revealed that oral pretreatment of C. procera (50, 100, and 200 mg/kg b.w.) for 1, 7, and 14 days to cyclophosphamide-treated animals significantly reduced chromosomal abnormalities as well as DNA fragmentation in a dose-dependent manner. Moreover, C. procera extract had antimicrobial and antigenotoxic effects against CP-induced genotoxicity.

Identification of Causative agents associated with decay of Trees Twig and Orchards Die-back and their Impacts on Vessels of Citrus, Date Palm and Ficus.

The present work is concerned with the studies of the organism causing wood decay of twigs and branches of citrus orchards, date palm Phoenix dactylifera L, and ficus trees. A survey for the occurrence of this disease in the main growing areas was achieved by the researchers. The following species of citrus orchards [lime (C. aurantifolia), sweet orange (C. sinensis), and mandarin (C. reticulate)] were surveyed, and so date palm and ficus trees. However, the results showed that the incidence of this disease was about 100%. Laboratory examinations data revealed mainly two fungal species causing the disease: Physalospora rhodina (P.rhodina)  and Diaporthe citri (D. citri). In addition that, both fungi, which are P. rhodina and D. citri affected the vessels of tree tissues. According to the pathogenicity test, the fungus P. rhodina caused a breakdown of parenchyma cells, and the fungus D. citri caused the darkening of the xylem.

In vitro and in vivo hypolipidemic properties of the aqueous extract of Spirulina platensis, cultivated in colored flasks under artificial illumination.

BACKGROUND: Spirulina is blue-green algae that grows mainly in tropical and subtropical lakes and is commonly used due to its nutritional features including high concentrations of protein, vitamins, mineral salts, carotenoids and antioxidants. This study aimed to investigate the anti-hypercholesterolemic potential of aqueous extract of Spirulina platensis cultivated in different colored flasks under artificial illumination; in vitro and in the diet induced hypercholesterolemic Swiss albino mice. METHODS: Spirulina platensis was cultivated in red, blue, green and colorless Erlenmeyer flasks containing Zarrouk's medium under aerobic conditions, with incessant illumination by artificial cool white fluorescent with light intensity of 2500 lux (35 µmol photon m-2 s-1). Chlorophyll a and total carotenoid contents were estimated using colorimetric methods, fatty acids composition was determined by GC-Mass, in vitro and in vivo anti-cholesterol assays were used in assessing the anti-hypercholesterolemia potential of obtained Spirulina cells. RESULTS: The results showed that the highest cell dry weight, chlorophyl a, and carotenoid of S. platensis were observed in colorless flasks and that the lowest values were recorded with the green colored flasks. Also, the hot water extract of S. platensis obtained from colorless flasks at a concentration of 15 mg/mL after 60 min of incubation exhibited the greatest reduction of cholesterol level. Gas chromatography-mass spectrometry analysis of S. platensis methanolic extract showed 15 bioactive compounds were identified and grouped according to their chemical structures. An experimental model of hypercholesterolemic mice had been examined for impact of S. platensis individually and combined with atorvastatin drug. All S. platensis groups resulted in a remarkable decrease in plasma total cholesterol, triglycerides and low density lipoprotein; and increase in high density lipoprotein. CONCLUSION: The present study concluded that the hot aqueous extract of S. platensis developed in colorless flasks is recommended as a natural source for bioactive compounds, with anti-cholesterol and antioxidant potentialities.

Author Correction: Bioprocessing strategies for cost-effective simultaneous removal of chromium and malachite green by marine alga Enteromorpha intestinalis.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Bioprocessing strategies for cost-effective simultaneous removal of chromium and malachite green by marine alga Enteromorpha intestinalis.

A large number of industries use heavy metal cations to fix dyes in fabrication processes. Malachite green (MG) is used in many factories and in aquaculture production to treat parasites, and it has genotoxic and carcinogenic effects. Chromium is used to fix the dyes and it is a global toxic heavy metal. Face centered central composite design (FCCCD) has been used to determine the most significant factors for enhanced simultaneous removal of MG and chromium ions from aqueous solutions using marine green alga Enteromorpha intestinalis biomass collected from Jeddah beach. The dry biomass of E. intestinalis samples were also examined using SEM and FTIR before and after MG and chromium biosoptions. The predicted results indicated that 4.3 g/L E. intestinalis biomass was simultaneously removed 99.63% of MG and 93.38% of chromium from aqueous solution using a MG concentration of 7.97 mg/L, the chromium concentration of 192.45 mg/L, pH 9.92, the contact time was 38.5 min with an agitation of 200 rpm. FTIR and SEM proved the change in characteristics of algal biomass after treatments. The dry biomass of E. intestinalis has the capacity to remove MG and chromium from aquatic effluents in a feasible and efficient manner.

Effect of dietary antioxidant supplementation (Cuminum cyminum) on bacterial susceptibility of diabetes-induced rats.

Diabetic patients are at risk of acquiring infections. Chronic low-grade inflammation is an important factor in the pathogenesis of diabetic complication. Diabetes causes generation of reactive oxygen species that increases oxidative stress, which may play a role in the development of complications as immune-deficiency and bacterial infection. The study aimed to investigate the role of a natural antioxidant, cumin, in the improvement of immune functions in diabetes. Diabetes was achieved by interperitoneal injection of streptozotocin (STZ). Bacterial infection was induced by application of Staphylococcus aureus suspension to a wound in the back of rats. The antioxidant was administered for 6 weeks. Results revealed a decrease in blood glucose levels in diabetic rats (p < 0.001), in addition to improving immune functions by decreasing total IgE approaching to the normal control level. Also, inflammatory cytokine (IL-6, IL-1ß and TNF) levels, as well as total blood count decreased in diabetic rats as compared to the control group. Thus, cumin may serve as anti-diabetic treatment and may help in attenuating diabetic complications by improving immune functions. Therefore, a medical dietary antioxidant supplementation is important to improve the immune functions in diabetes.