Effect of Extraction Solvents on Total Polyphenolic Content and Antioxidant Capacity of Syzygium Aromaticum L. Flower Bud from Ethiopia

Phytochemical composition, antioxidant, antibacterial, and enzyme inhibitory activities of organic extracts from flower buds of Cleistocalyx operculatus (Roxb.) Merr. et Perry

Cleistocalyx operculatus flower buds have been widely used in traditional medicine because of their rich content of bioactive constituents. In this study, we obtained seven solvent extracts from the flower buds and evaluated their total phenolic (TPC), flavonoid (TFC), tannin (TTC), triterpenoid saponin (TSC), and alkaloid (TAC) contents. We assessed antioxidant activities using the DPPH assay and also looked at antimicrobial and enzyme inhibitory effects. The water extract possessed the highest TPC (328.9 mg GAE/g extract), followed by ethanol, methanol, and hexane extracts (85.4-101.5 mg GAE/g extract). Chloroform, butanol, ethyl acetate, and ethanol extracts had high TSCs (245.4-287.2 mg OAE/g extract). The hexane extract was richest in TTC and TFC (32.7 mg CE/g extract and 81.1 mg QE/g extract, respectively). Ethanol and methanol extracts exhibited the strongest antioxidant activities (IC50 values of 25.2 and 30.3 μg/ml, respectively), followed by the water extract (IC50 of 40.2 μg/ml). The hexane extract displayed the most growth-inhibitory activity against Helicobacter pylori ATCC51932 and ATCC43504 strains and Salmonella enterica serovar Typhimurium ATCC13311 (MIC values of 0.06, 0.13, and 0.4 mg/ml, respectively). Moreover, the hexane extract revealed the strongest inhibition of H. pylori urease activity (IC50 of 4.51 μg/ml), whereas the water and methanol extracts had potent inhibitory effects on α-glucosidase activity (IC50 values of 9.9 and 15.1 μg/ml, respectively). These flower bud extracts could be used for health protection, especially in preventing bacterial infections and inhibiting enzymes associated with various human diseases. Further investigation into the application of C. operculatus flower buds in the food and pharmaceutical industries is necessary.

Effectiveness of some plant extracts in biocontrol of induced onion basal rot disease in greenhouse conditions

One of Egypt's most notable and historically significant vegetable crops is the Liliaceae plant, Allium cepa L. In this study, the effectiveness of methanolic extracts of Artemisia absinthium leaves, Calotropis procera latex, Moringa oleifera seeds, and Syzygium aromaticum clove was investigated in vitro and, in a greenhouse, setting against Fusarium oxysporum, the pathogen that causes onion basal rot in Assiut Governorate, Egypt. The S. aromaticum extract exhibited the inhibition peak (63.3%), whereas the A. absinthium extract had the lowest inhibition impact against F. oxysporum growth (41.1%). The gas chromatography-mass spectroscopy (GC-MS) analysis revealed that 82 important compounds, with abundances ranging from low to high, were present in the tested S. aromaticum's methanolic extract. The primary components were acetaldehyde, hydroxy- and 2-propanone, 1,1,3,3-tetrachloro-(42.71%), 1,2-ethanediol, and methyl alcohol (34.01%). In comparison to the infected control, the disease severity was significantly reduced by 20% with the use of a plant extracts mixture and Dovex 50% and increased by 62.22% with the use of an extract from A. absinthium. When compared to the infected control, onion plant fresh weight and dry weight were considerably higher under the clove extract therapy. The plant extracts used in this study's testing contain a number of active ingredients, including amino acids, vitamins, minerals, antioxidants, and enzymes, which is probably why they have such positive impacts. The application of a combination of plant extracts was suggested as a feasible strategy for improving the growth and productivity of onion plants by the study's findings. More research is needed to comprehend the mechanisms by which plant extracts promote plant development and to optimize the concentration and timing of administration.

Nanophytosomal Gel of Heydotis corymbosa (L.) Extract against Psoriasis: Characterisation, In Vitro and In Vivo Biological Activity

The current study was conducted to examine the possible advantages of Heydotis corymbosa (L.) Lam. extract nanogel as a perspective for enhanced permeation and extended skin deposition in psoriasis-like dermatitis. Optimised nanophytosomes (NPs) were embedded in a pluronic gel base to obtain nanogel and tested ex vivo (skin penetration and dermatokinetics) and in vivo. The optimised NPs had a spherical form and entrapment efficiency of 73.05 ± 1.45% with a nanosized and zeta potential of 86.11 nm and -10.40 mV, respectively. Structural evaluations confirmed encapsulation of the drug in the NPs. Topical administration of prepared nanogel to a rat model of psoriasis-like dermatitis revealed its specific in vivo anti-psoriatic efficacy in terms of drug activity compared to the control and other formulations. Nanogel had improved skin integrity and downregulation of inflammatory cytokines. These findings suggest that developed phytoconstituent-based nanogel has the potential to alleviate psoriasis-like dermatitis with better skin retention and effectiveness.

Antioxidant Potential of Ethiopian Medicinal Plants and Their Phytochemicals: A Review of Pharmacological Evaluation

Background

Free radicals are very reactive molecules produced during oxidation events that in turn initiate a chain reaction resulting in cellular damage. Many degenerative diseases in humans, including cancer and central nervous system damage, are caused by free radicals. Scientific evidence indicates that active compounds from natural products can protect cells from free radical damage. As a result, the aim of this review is to provide evidence of the use of diverse Ethiopian medicinal plants with antioxidant properties that have been scientifically validated in order to draw attention and foster further investigations in this area.

Methods

The keywords antioxidant, radical scavenging activities, reactive oxygen species, natural product, Ethiopian Medicinal plants, and 2, 2-Diphenyl-1-picrylhydrazyl radical scavenging assay (DPPH) were used to identify relevant data in the major electronic scientific databases, including Google Scholar, ScienceDirect, PubMed, Medline, and Science domain. All articles with descriptions that were accessed until November 2022 were included in the search strategy.

Results

A total of 54 plant species from 33 families were identified, along with 46 compounds isolated. More scientific studies have been conducted on plant species from the Brassicaceae (19%), Asphodelaceae (12%), and Asteraceae (12%) families. The most used solvent and extraction method for plant samples are methanol (68%) and maceration (88%). The most examined plant parts were the leaves (42%). Plant extracts (56%) as well as isolated compounds (61%) exhibited significant antioxidant potential. The most effective plant extracts from Ethiopian flora were Bersama abyssinica, Solanecio gigas, Echinops kebericho, Verbascum sinaiticum, Apium leptophyllum, and Crinum abyssinicum. The best oxidative phytochemicals were Rutin (7), Flavan-3-ol-7-O-glucoside (8), Myricitrin (13), Myricetin-3-O-arabinopyranoside (14), 7-O-Methylaloeresin A (15), 3-Hydroxyisoagatholactone (17), β-Sitosterol-3-O-β-D-glucoside (22), Microdontin A/B (24), and Caffeic acid (39).

Conclusion

Many crude extracts and compounds exhibited significant antioxidant activity, making them excellent candidates for the development of novel drugs. However, there is a paucity of research into the mechanisms of action as well as clinical evidence supporting some of these isolated compounds. To fully authenticate and then commercialize, further investigation and systematic analysis of these antioxidant-rich species are required.

Determination of Polycyclic Aromatic Hydrocarbon Content in Garden Herbal Plants Using Liquid Chromatographic Analysis (HPLC-FL)

Polycyclic aromatic hydrocarbons (PAHs) are a group of chemical compounds generated as a result of the incomplete combustion of fossil fuels or wood. PAHs are known for their negative effect on living organisms, including teratogenic, carcinogenic and mutagenic activity. The objective of this study is to determine the contamination of three popular herbal species showing pro-health properties, i.e., lavender, parsley and mint, with polycyclic aromatic hydrocarbons, collected from three different backyard gardens in Poland. The concentration of PAHs in plant material was determined by high-performance liquid chromatography with a fluorescence detector (HPLC-FL). The concentration of eleven PAHs in plant material was determined with high-pressure liquid chromatography after extraction using the QuEChERS purification technique. Mint collected within an area of a mining and energy production complex (the city of Konin) was characterized by the highest Σ of 11 PAHs, equaled to 902.35 µg/g FW, with anthracene being the most abundant compound. However, it contained the lowest sum of PAHs, among all tested plants, with high carcinogenicity. Parsley from the city of Poznań showed the highest content of benzo[a]pyrene (BaP), showing the strongest carcinogenicity, while the highest value of BaP equivalent was calculated for mint collected in Konin. The obtained results suggest that the level and profile of plant contamination with PAHs depend on the species and the location of herb cultivation. In particular, mining and energy industry facilities are sources of PAHs, which contaminate plant material for further direct use or as bioactive herbal extracts.