RESUMO
In the last few decades, hydroxyapatite (HA) has become one of the most highly prized biominerals in the biomedical industry for orthopedic and dental applications. The focus of this research was to synthesize biomimetic HA from Tridax procumbens (TP) leaf extract and investigate their antibiofilm properties. The HA was made using the sol-gel method and the HA-TP biocomposite was made by precipitation method. The d.nm size of HA and HA-TP biocomposite was determined as 193.28 and 258.14 d.nm, respectively. The zeta potential of HA and HA-TP biocomposite was determined as ?21.2 and ?18.3 mV, respectively, and found highly stable. The FTIR study revealed that phytochemicals of TP were successfully impregnated into HA-TP biocomposite. The HA and HA-TP biocomposite were found spherical and agglomerated from SEM analysis. In HR-TEM analysis, the average diameter of the HA and HA-TP biocomposite were 16.57 – 64.22 nm and 51.71 – 138.68 nm, respectively. According to the EDX analysis, HA is primarily composed of calcium, oxygen, and phosphate, whereas, HA-TP biocomposite is primarily composed of calcium, phosphate, oxygen, and carbon. In the antioxidant assay, the IC50 value (concentration required to scavenge 50% of free radicals) of HA-TP biocomposite was determined as 156.69 ± 14.02 and 180.21 ± 12.84 µg/mL in DPPH and ABTS free radical scavenging assays, respectively. The MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) of as-synthesized HA-TP biocomposite against Staphylococcus aureus – ATCC 13565 and Escherichia coli – MTCC 41 were observed as 181.09 ± 21.47 and 317.30 ± 41.03, and 157.59 ± 32.18 and 264.03 ± 21.58 µg/mL, respectively. The as-synthesized HA-TP biocomposite has detrimentally affected the biofilm formation of both the tested bacteria S. aureus – ATCC 13565 and E. coli – MTCC 41. The study concluded that the as-synthesized HA-TP biocomposite could be highly helpful in the biomedical field for alleviating oxidative-stress-related disorders and inhibiting microbial biofilm formation.
RESUMO
The study is directed to establish the minimizing effects of Syzygium aromaticum, Ocimum sanctum, and Cananga odorata essential oils on the growth and ochratoxin A (OTA) level of Aspergillus ochraceus and Penicillium verrucosum in maize grains. S. aromaticum essential oil (SAEO), O. sanctum essential oil (OSEO), and C. odorata essential oil (COEO) were extracted by hydro-distillation technique, and a total of 50, 44, and 48 chemical constituents were identified by gas chromatography-mass spectrometry (GC-MS), respectively.The SAEO and OSEO belong to the chemotype of eugenol, whereas, COEO was found to be the chemotype of thymol, limonene, and ?-ylangene. The antifungal activity of essential oils (EOs) was determined by the micro-well dilution technique. The SAEO showed superior antifungal activity compared to OSEO, COEO, and synthetic antifungal agent nystatin, and its minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values against A. ochraceous and P. verrucosum were noticed as 1251 ± 42.32 and 1878 ± 28.47 µg/mL, and 0815 ± 22.69 and 1146 ± 51.19 µg/mL, respectively.The antifungal mechanism of EOs was unveiled by assessing the intracellular reactive oxygen species (ROS), ergosterol content, and membrane integrity. The antifungal investigations found that EOs caused fungal mortality by increasing the intracellular ROS, depleting ergosterol synthesis, and distracting membrane integrity. Finally, antifungal and antimycotoxin activity of EOs was demonstrated in maize grains. The SAEO, OSEO, and COEO have reduced the complete fungal growth and OTA level of A. ochraceous and P. verrucosum correspondingly at 2500 and 2500, 3500 and 2500, and 3500 and 3500 µg/g in maize. The EOs could act as natural antifungal agents; protect foodstuffs from fungal infection and mycotoxins during storage.