Water was bubbled with gases including nitrogen (N2), oxygen (O2), hydrogen (H2), carbon dioxide (CO2), and air for 10 min and phenolics from green tea leaves were extracted using the prepared gas‐bubbled water. To retain the gases in water, the extraction conditions were maintained in an air‐tight container at room temperature under magnetic stirring. Radical scavenging ability, total phenolic content, and phenolic profiles of the extracts were analyzed, and gas‐bubbled water was examined to explain the differences in phenolic contents. Overall, green tea infusion prepared from H2‐bubbled water contained significantly high levels of total phenolic compounds and antioxidant activity compared to other gas‐bubbled waters including N2, O2, CO2, and air (P < 0.05).Control samples and those bubbled with CO2 showed the lowest antioxidant activities in green tea infusion. However, green tea extracts with O2 bubbling showed the lowest catechin content. Green tea leaves treated with hydrogen gas‐bubbled water had much greater damage to their surface morphological properties compared to the other groups, which may explain the higher yield of phenolic compounds. Overall, hydrogen gas‐bubbled water showed better extraction yield of phenolics from green tea leaves than other gas‐bubbled water. Practical Application Green tea or green tea infusion has diverse health beneficial functionality due to the presence of phenolic compounds. In this study, different gases including nitrogen, oxygen, hydrogen, and carbon dioxide were treated in water and these gas‐bubbled water were used to extract phenolics from green tea leaves. Among them, hydrogen‐bubbled water extracted the highest phenolic contents from tea leaves and showed the highest in vitro antioxidant ability in green tea infusion compared to other gas‐bubbled water. This new knowledge could help to produce green teas with higher antioxidant activity in beverage industry.

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Effects of lecithin (HLB 4.5) on oxidative stability of non‐stripped or stripped corn oil are determined during storage at 50 °C. Headspace oxygen content of non‐stripped corn oil containing lecithin decreased less with the increasing concentration of lecithin (300–3000 ppm). Lecithin‐supplemented non‐stripped corn oil near and above critical micelle concentration (CMC, 1288 ppm) had higher oxidative stability as compared to other samples according to conjugated dienoic acid and p‐anisidine value assays. Antioxidant and tocopherol concentrations in non‐stripped corn oil samples containing lecithin near CMC are found to be the highest. Stripped corn oil has CMC of 1790 ppm lecithin and 600 ppm lecithin shows higher antioxidant properties than other concentration of lecithin from 1200 to 3000 ppm. Presence of phospholipids affected oxidative stability of bulk oils. Non‐stripped corn oil supplemented with lecithin near CMC shows the highest oxidative stability, which could be due to the incorporation of tocopherols into the association colloids formed by the added lecithin. Practical Application: Controlling rate of lipid oxidation in bulk oils is one of the important topics in lipid science. Addition of commercially available lecithin (HLB 4.5) could enhance the oxidative stability in non‐stripped corn oil especially, at the concentration of lecithin near CMC. Presence of phospholipids affected oxidative stability of bulk oils. By using knowledge shown in this study, food industries could save costs by optimizing the lecithin concentration in bulk oils, which could be used as ingredients of many processed foods. Addition of commercially available lecithin enhances oxidative stability in non‐stripped corn oil. Lecithin near or over its critical micelle concentration shows higher antioxidant activity in non‐stripped oil compared to other concentrations of lecithin. Added lecithin increases tocopherol stability, especially α‐tocopherol in non‐stripped bulk oil during storage. For stripped corn oil, 600 ppm lecithin only shows some antioxidant power and other concentrations do not enhance oxidative stability.

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Herewith, we approached a synthesis of new biphenyl porphyrin derivative and confirmed its structure with 1H-NMR and 13C-NMR studies, FT-IR and mass analytical methods. The porphyrin derivative grafted with TiO2 and the composite (PORBP-TiO2) was further confirmed with different analytical techniques like diffuse reflectance spectra, XRD, FT-IR, XPS, SEM analysis. PORBP-TiO2 was checked for photodegradation of methylene blue in visible light condition and degradation results were compared with bare TiO2. Our newly synthesized photocatalyst showed a very fast and efficient photocatalytical activity in comparison with bare TiO2. Fluoresence life time results also supported the strong photocatalytic activity of PORBP-TiO2. The reusability studies also showed that PORBP-TiO2 is having very good stability upto 10 cycles also. Finally we proposed a suitable catalytic diagram for PORBP-TiO2 photocatalysis.