Antioxidant activity and some quality characteristics of buffalo yoghurt fortified with peanut skin extract powder.

Peanut is an important crop grown worldwide. Peanut skin, the byproduct of peanut processing is a valuable byproduct due to its content of many functional components. Therefore, this study aimed to evaluate the effect of fortification of yoghurt with peanut skin extract powder (PSEP) at 50, 100 and 200 mg/L milk on the antioxidant activity (radical scavenging activity RSA%) and some quality characteristics of the resultant yoghurt during cold storage. The obtained results revealed that total phenolic content of PSEP is 109.46 mg GAE/g while it's radical scavenging activity % reached 90.57%. Fortification of yoghurt with PSEP increased the apparent viscosity, antioxidant activity, and total phenolic, acetaldehyde, and diacetyl contents as compared to control, while the syneresis of fortified yoghurt was reduced. Microbiological analysis showed that fresh control yoghurt had the highest counts of Streptococcus thermophilus and Lactobacillus bulgaricus and decreased at the end of storage in all treatments. Both control and T1 (the low concentration of PSEP) gained the highest acceptability; therefore, it was recommended that fortification of yoghurt with 50 mg of PSEP/L is more preferable than the other concentrations. In addition, it could be considered as a natural antioxidant source in formulating functional yoghurt either in industrial and/or small industrial scale.

Improving the Functional Activities of Curcumin Using Milk Proteins as Nanocarriers.

Curcumin is one of the most common spices worldwide. It has potential benefits, but its poor solubility and bioavailability have restricted its application. To overcome these problems, this study aimed to assess the efficacy of sodium caseinate (SC), α-lactalbumin (α-La), ß-lactoglobulin (ß-lg), whey protein concentrate (WPC) and whey protein isolate (WPI) as nanocarriers of curcumin. Furthermore, the antioxidant, anticancer and antimicrobial activities of the formed nanoparticles were examined. The physicochemical characteristics of the formed nanoparticles as well as the entrapment efficiency (%) and the in vitro behavior regarding the release of curcumin (%) were examined. The results showed that the formation of curcumin-milk protein nanoparticles enhanced both the entrapment efficiency and the in vitro behavior release of curcumin (%). Cur/ß-lg nanoparticles had the highest antioxidant activity, while SC and WPC nanoparticles had the highest anticancer effect. The antimicrobial activity of the formed nanoparticles was much higher compared to curcumin and the native milk proteins.

Antiviral Action of Native and Methylated Lactoferrin and ß-Lactoglobulin against Potato Virus Y (PVY) Infected into Potato Plants Grown in an Open Field.

Potato plants are liable to PVY infection without efficient control. Therefore, they were cultivated under greenhouse and open field conditions, artificially infected with PVY and then treated after 15 days of infection with native lactoferrin (LF) and native ß-lactoglobulin (BL) and their esterified forms, MLF (methylated lactoferrin) and BLM (methylated ß-lactoglobulin) to test the efficiency of this approach. Viral replication was inhibited by the applied substances, particularly the methylated forms, in a concentration-dependent manner, where the concentration of 500 µg·mL-1 was sufficient for plant protection against the PVY infection. An open field experiment showed that one single application of the antiviral substance was enough for maximum inhibitory action against PVY. The modified milk proteins induced higher inhibitory action on PVY virus replication in the plants, compared to their native forms, which was reflected by potato growth and yield. Using the dot blot hybridization and RT-PCR techniques to detect PVY in the experimental plants showed the supremacy of native and esterified LF in inhibiting the targeted virus. The generally observed scanning electronic microscopy (SEM) structural deformations and irregular appearance in PVY particles when treated with MLF and BLM revealed their direct action. BLM, MLF and LF are efficient antiviral agents against PVY. They can not only abolish the observed PVY-induced reduction in potato growth and tuber yield, but also further increase them to higher levels than negative control.

Antiviral Activity of Curcumin Loaded Milk Proteins Nanoparticles on Potato Virus Y.

BACKGROUND AND OBJECTIVE: Potato is one of the world's leading vegetable crops. Potato viral diseases cause adversely effects on the agricultural sector. Recently there is a growing interest to control plant viruses using spices and herbs (including curcumin). Poor solubility of curcumin in water limited its applications. Therefore, the main objective of the present study was to evaluate the effect of antiviral activity of curcumin-milk proteins nanoparticles against potato virus Y (PVY). MATERIALS AND METHODS: Curcumin-milk proteins nanoparticles were prepared via ionic gelation method. The antiviral activity of the resultant nanoparticles against PVY was evaluated at different concentrations (500, 1000 and 1500 mg/100 mL). Chlorophyll content as well as the activity of peroxidase (POX) and polyphenol oxidase (PPO) was examined. RESULTS: Curcumin-milk proteins nanoparticles showed inhibitory effect on PVY in a concentration dependent manner. CONCLUSION: Curcumin-milk proteins nanoparticles displayed a successful tool to control the PVY under green house conditions.

Antioxidant and antibacterial activities of bioactive peptides in buffalo's yoghurt fermented with different starter cultures.

The effect of Lactobacillus acidophilus 20552 ATCC (T2) or Lactobacillus helveticus CH 5 (T3) in combination with yoghurt starter (1:1) on the antioxidant and antibacterial activities of the bioactive peptides present in buffalo's yoghurt was studied. The SDS-PAGE results indicate that all caseins were completely hydrolyzed by both strains, whereas whey protein fractions were still present. All starter cultures have the ability to produce low-molecular-weight bioactive peptides, most of which were originated from ß-casein and fewer from αs1 casein. The antioxidant activity (%) of the water-soluble peptide extract from yoghurt samples increased in all samples during storage. Samples containing Lb. helveticus CH 5 showed the highest values. All yoghurt treatments displayed antibacterial activity against Escherichia coli. Control yoghurt and T3 showed higher antibacterial activity on E. coli, Staphylococcus aureus, and Bacillus cereus as compared to T2.

Protective effect of whey proteins against nonalcoholic fatty liver in rats.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome and can vary from hepatic steatosis to end-stage liver disease. It is the most common liver disease and its prevalence is increasing worldwide. In the present study, the effect of whey proteins on some parameters of NAFLD was investigated. RESULTS: Oral administration of the studied whey proteins products reduced the final body weight of rats. There was a significant reduction effect (P<0.05) of the tested proteins on hepatic triglycerides, liver enzymes (ALT and AST), lipid peroxidation (malondialdehyde level) and serum glucose. Feeding on whey proteins caused an increase in the reduced glutathione. Hepatic content of reduced glutathione was not affected by any of the used whey proteins, but it showed an increasing tendency (P>0.05). Liver histology showed an improvement of fatty infiltration in hepatocytes from whey protein groups and gives the histology of liver a normal appearance. CONCLUSIONS: The obtained results indicate a possible role for oral administration of whey proteins in the regulation of liver biochemistries in a rat's model of NAFLD. This regulatory effect of whey proteins was accompanied by an improvement in fatty infiltration in hepatocytes and a reduction of oxidative stress parameters.

Effectiveness of esterified whey proteins fractions against Egyptian Lethal Avian Influenza A (H5N1).

BACKGROUND: Avian influenza A (H5N1) virus is one of the most important public health concerns worldwide. The antiviral activity of native and esterified whey proteins fractions (α- lactalbumin, ß- lactoglobulin, and lactoferrin) was evaluated against A/chicken/Egypt/086Q-NLQP/2008 HPAI (H5N1) strain of clade 2.2.1 (for multiplicity of infection (1 MOI) after 72 h of incubation at 37 °C in the presence of 5% CO2) using MDCK cell lines. RESULT: Both the native and esterified lactoferrin seem to be the most active antiviral protein among the tested samples, followed by ß- lactoglobulin. α-Lactalbumin had less antiviral activity even after esterification. CONCLUSION: Esterification of whey proteins fractions especially lactoferrin and ß-lactoglobulin enhanced their antiviral activity against H5N1 in a concentration dependent manner.

Inhibition of tomato yellow leaf curl virus (TYLCV) using whey proteins.

The antiviral activity of native and esterified whey proteins fractions (alpha-lactalbumin, beta-lactoglobulin, and lactoferrin) was studied to inhibit tomato yellow leaf curl virus (TYLCV) on infected tomato plants. Whey proteins fractions and their esterified derivatives were sprayed into TYLCV-infected plants. Samples were collected from infected leaves before treatment, 7 and 15 days after treatment for DNA and molecular hybridization analysis. The most evident inhibition of virus replication was observed after 7 and 15 days using alpha-lactoferrin and alpha-lactalbumin, respectively. Native and esterified lactoferrin showed complete inhibition after 7 days. On the other hand, native beta-lactoglobulin showed inhibition after 7 and 15 days whereas esterified beta-lactoglobulin was comparatively more effective after 7 days. The relative amount of viral DNA was less affected by the esterified alpha-lactalbumin whereas native alpha-lactalbumin inhibited virus replication completely after 15 days. These results indicate that native or modified whey proteins fractions can be used for controlling the TYLCV-infected plants.