Antibacterial effect of citrus press-cakes dried by high speed and far-infrared radiation drying methods

Citrus sinensis Peel Oil Extraction and Evaluation as an Antibacterial and Antifungal Agent

Throughout the tropical and subtropical climates, the genus Citrus can be found. The current study was conducted to extract the Citrus sinensis peel oil and evaluate its antibacterial, antifungal and antiparasitic potential. Petroleum ether was used to extract the C. sinensis peel oil through a Soxhlet apparatus. The antimicrobial and antifungal potential was determined via agar well diffusion method and minimum inhibitory concentrations (MIC) were calculated (test bacterial strains: Staphylococcus aureus, Escherichia coli and Streptococcus agalactiae; test fungal strains: Aspergillus flavus, Aspergillus niger, Altrnaria alternata). Antiparasitic activity against Leishmaniatropica was determined following standard protocol using amphotericin-B as positive and Dimethyl Sulfoxide (DMSO) as a negative control and the percentage inhibition was calculated. The oil extracted was brownish yellow with a tangy smell, water-insoluble, density (0.778 g/cm³) and specific gravity (0.843 g/cm). In antibacterial activity, the diameter of the zone of inhibition was maximum against E. coli (14 mm) and minimum for S. agalactiae (10 mm). While in antifungal activity diameter of the zone of inhibition was maximum against A. flavus (12.5 mm) and minimum for A. alternata (8.6 mm). S. agalactiae exhibited the minimum MIC value (6 mg/mL) and in fungal strains A. alternata exhibited the minimum value (2 mm). Citrus sinensis peel oil displayed antileishmanial efficiency of 60% at 50 μg/mL concentration after 48 h of incubation. C. sinensis peel oil demonstrated antimicrobial capabilities, implying that it could be used as a natural preservative in food or as an effective treatment against a variety of pathogenic organisms. Industries should extract oil from the waste of citrus fruits which will be beneficial from an economic point of view.

Apoptotic role of marine sponge symbiont Bacillus subtilis NMK17 through the activation of caspase-3 in human breast cancer cell line

The aim of the present study was to evaluate the diverse potential biological activity of partially purified crude extract (PPCEBS) of marine Bacillus subtilis NMK17 associated with marine sponge Clathria frondifera. Symbionts were isolated from a marine sponge, only the potential strain which exhibited apoptosis was sequenced using 16S rRNA and extract of the active strain was subjected to purification using HPLC. The potential pro-apoptotic role of PPCEBS was investigated in MCF-7 human breast cancer cell line for cytotoxicity by MTT assay, which showed dose-dependent cytotoxicity on 24 h of exposure. The apoptotic findings demonstrated that PPCEBS significantly induces apoptosis, which was characterised by apoptotic morphological changes. Further, an increased expression of the Caspase 3 and Bax whereas decreased Bcl-2 was confirmed by immunofluorescence and western blotting analysis in MCF-7 cell line, which revealed that PPCEBS has potent apoptosis-inducing property. Added to the desirable apoptotic activity, PPCEBS exhibited excellent antibacterial and antioxidant activities too. The pharmacological effect of the marine sponge-associated bacteria from Gulf of Mannar India needs further attention in discovering new bioactive compounds. Our results suggested that the compounds present in the PPCEBS in marine bacterial B. subtilis NMK17 could be candidates for developing an apoptosis-specific drug with minimal toxicity. This study indicated that marine sponge-associated bacteria could be a good source to find the cytotoxic metabolites which would induce apoptosis and cause cancer cell death. Also, this study explores that marine natural products as a potential source of pharmaceuticals.

Effect of Artificial LED Light and Far Infrared Irradiation on Phenolic Compound, Isoflavones and Antioxidant Capacity in Soybean (Glycine max L.) Sprout

The effect of light emitting diode (LED) light and far infrared irradiation (FIR) on total phenol, isoflavones and antioxidant activity were investigated in soybean (Glycine max L.) sprout. Artificial blue (470 nm), green (530 nm) LED and florescent light (control) were applied on soybean sprout, from three to seven days after sowing (DAS) in growth chamber. The photosynthetic photon flux density (PPFD) and photoperiod was 150 ± 5 μmol m⁻²s⁻¹ and 16 h, respectively. The FIR was applied for 30, 60 and 120 min at 90, 110 and 130 °C on harvested sprout. Total phenolic content (TP) (59.81 mg/g), antioxidant capacity (AA: 75%, Ferric Reduction Antioxidant Power (FRAP): 1357 µM Fe²⁺) and total isoflavones content (TIC) (51.1 mg/g) were higher in blue LED compared to control (38.02 mg/g, 58%, 632 µM Fe²⁺ and 30.24 mg/g, respectively). On the other hand, TP (64.23 mg/g), AA (87%), FRAP (1568 µM Fe²⁺) and TIC (58.98 mg/g) were significantly increased by FIR at 110 °C for 120 min among the treatments. Result suggests that blue LED is the most suitable light to steady accumulation of secondary metabolites (SM) in growing soybean sprout. On the other hand, FIR at 110 °C for 120 min is the best ailment to induce SM in proceed soybean sprout.