Assessing some Cladosporium species in the biodegradation of petroleum hydrocarbon for treating oil contamination.

AIM: Biodegradation is a cost-effective and eco-friendly treatment for oil-contaminated materials using microorganisms. Bacteria and fungi can degrade petroleum by using it as an energy source and this may provide an enormous scope to remediate soils contaminated with petroleum and oil. This study aimed to assess the biodegradation of petroleum hydrocarbons by certain Cladosporium species. METHODS AND RESULTS: By using traditional and spectroscopic assessment analysis, qualitative screening was carried out using Cladosporium spores isolated from air and cultured on mineral salt medium supplemented with petroleum hydrocarbon as the sole carbon source, followed by quantitative assessment using gas chromatography-mass spectroscopy. Nineteen Cladosporium strains from a total of 212 isolates exhibited remarkable capability to degrade petroleum hydrocarbon, representing four species (C. herbarum, C. macrocarpum, C. sphaerospermum, and C. cladosporioides). The results were expressed in terms of biodegradation percentage and optical density of hydrocarbon using a standard calibration curve. The highest reduction of petroleum hydrocarbon was observed with five Cladosporium strains belonging to two species (C. sphaerospermum and C. cladosporioides). CONCLUSION: This study succeeded in isolating several Cladosporium strains (from the air) with a high ability to degrade crude oil that can be used as biological agents to control petroleum pollution in soils and seas. The addition of a surfactant (Tween 80) enhanced the degradation of crude oil reaching a final concentration of 0.4%. Based on these results, the present study could indicate some unique prospects in the field of bioremediation and biodegradation of petroleum-contaminated soil. SIGNIFICANCE AND IMPACT OF STUDY: This study gives unique prospects in the field of bioremediation and biodegradation of petroleum-contaminated soil.

Molecular Interaction Studies and Phytochemical Characterization of Mentha pulegium L. Constituents with Multiple Biological Utilities as Antioxidant, Antimicrobial, Anticancer and Anti-Hemolytic Agents.

Multiple biological functions of Mentha pulegium extract were evaluated in the current work. Phytochemical components of the M. pulegium extract were detected by Gas Chromatography-Mass Spectrometry (GC-MS) and High-performance liquid chromatography (HPLC). Moreover, M. pulegium extract was estimated for antioxidant potential by 2,2-Diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical scavenging, antimicrobial activity by well diffusion, and anticoagulant activity via prothrombin time (PT) and activated partial thromboplastin time (APTT). GC-MS analysis detected compounds including cholesterol margarate, stigmast-5-en-3-ol, 19-nor-4-androstenediol, androstan-17-one, pulegone-1,2-epoxide, isochiapin B, dotriacontane, hexadecanoic acid and neophytadiene. Chrysoeriol (15.36 µg/mL) was followed by kaempferol (11.14 µg/mL) and 7-OH flavone (10.14 µg/mL), catechin (4.11 µg/mL), hisperdin (3.05 µg/mL), and luteolin (2.36 µg/mL) were detected by HPLC as flavonoids, in addition to ferulic (13.19 µg/mL), cinnamic (12.69 µg/mL), caffeic (11.45 µg/mL), pyrogallol (9.36 µg/mL), p-coumaric (5.06 µg/mL) and salicylic (4.17 µg/mL) as phenolics. Antioxidant activity was detected with IC50 18 µg/mL, hemolysis inhibition was recorded as 79.8% at 1000 µg/mL, and PT and APTT were at 21.5 s and 49.5 s, respectively, at 50 µg/mL of M. pulegium extract. The acute toxicity of M. pulegium extract was recorded against PC3 (IC50 97.99 µg/mL) and MCF7 (IC50 80.21 µg/mL). Antimicrobial activity of M. pulegium extract was documented against Bacillus subtilis, Escherichia coli, Pseudomonasaureus, Candida albicans, Pseudomonas aeruginosa, but not against black fungus Mucor circinelloides. Molecular docking was applied using MOE (Molecular Operating Environment) to explain the biological activity of neophytadiene, luteolin, chrysoeriol and kaempferol. These compounds could be suitable for the development of novel pharmacological agents for treatment of cancer and bacterial infections.

Anticancer, antioxidant, antiviral and antimicrobial activities of Kei Apple (Dovyalis caffra) fruit.

Secondary plant metabolites remain one of the key sources of therapeutic agents despite the development of new approaches for the discovery of medicinal drugs. In the current study, chemical analysis, and biological activities of Kei apple (Dovyalis caffra) methanolic extract were evaluated. Chemical analysis was performed using HPLC and GC-MS. Antiviral and anticancer effect were assessed using the crystal violet technique and activity against human liver cells (HepG2), respectively. Antibacterial activity was tested with the disc diffusion method. The obtained results showed that chlorogenic acid (2107.96 ± 0.07 µg/g), catechin (168 ± 0.58 µg/g), and gallic acid (15.66 ± 0.02 µg/g) were the main bioactive compounds identified by HPLC techniques. While, compounds containing furan moieties, as well as levoglucosenone, isochiapin B, dotriacontane, 7-nonynoic acid and tert-hexadecanethiol, with different biological activities were identified by GC-MS. Additionally, inhibition of 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) scavenging was 79.25% at 2000 µg/mL, indicating its antioxidant activity with IC50 of 728.20 ± 1.04 µg/mL. The tested extract exhibited potential anticancer activity (58.90% toxicity) against HepG2 cells at 1000 µg/mL. Potential bacterial inhibition was observed mainly against Escherichia coli and Proteus vulgaris, followed by Staphylococcus aureus and Bacillus subtilis with a diameter of growth inhibition ranging from 13 to 24 mm. While weak activities were recorded for fungi Candida albicans (10 mm). The extract showed mild antiviral activity against human coronavirus 229E with a selective index (SI) of 10.4, but not against human H3N2 (SI of 0.67). The molecular docking study's energy ratings were in good promise with the experiment documents of antibacterial and antiviral activities. The findings suggest that D. caffra juice extract is a potential candidate for further experiments to assess its use as potential alternative therapeutic agent.