Efficacy of Reuterin and Bacteriocins Nisin and Pediocin in the Preservation of Raw Milk from Dairy Farms.

RESEARCH BACKGROUND: In the current scenario of milk production in developing and developed countries, several factors influence the shelf-life of raw milk and add significant numbers of microbial contaminants that drastically lower the initial microbial quality leading to milk spoilage by the time it reaches the processing units. EXPERIMENTAL APPROACH: The present study was undertaken to investigate the biopreservative efficacy of reuterin system along with different combinations of bacteriocins in controlling the initial microflora of raw milk at farm level. Lactobacillus reuteri strain LR47, having effective antimicrobial activity, was shortlisted from our previous study and further characterized for reuterin production and tested in raw milk system. RESULTS AND CONCLUSIONS: Preliminary testing of the cell-free supernatant from L. reuteri LR47 demonstrated significant growth inhibition of the majority of the tested bacterial indicators of milk spoilage. Further genetic analysis of the L. reuteri LR47 revealed the presence of two genes (pduC and dhaB) involved in the utilization of glycerol to produce reuterin via two different pathways. The strain LR47 was also found to possess comparatively higher capacity to convert glycerol into reuterin when checked through colorimetric assay. In the raw milk biopreservation experiment with reuterin alone or in combination with bacteriocins, the highest level of growth suppression in the total bacterial load and coliform counts was observed in the sample that was treated with a combination of reuterin, nisin and pediocin. The treatment combining these three natural biopreservatives at specific concentrations was able to maintain the initial microbial quality and extend the shelf-life of raw milk by 6 h at 37 °C based on the microbial counts and physicochemical properties, viz. pH and titratable acidity. In conclusion, the results confirm that the use of reuterin in combination with bacteriocins is a promising approach for temporary control of the raw milk microflora and extension of its shelf-life until further processing. NOVELTY AND SCIENTIFIC CONTRIBUTION: This study demonstrates for the first time the use of reuterin for the extension of shelf-life of raw milk as an alternative treatment method.

Protective and Modulatory Effects of Trapa bispinosa and Trigonella foenum-graecum on Neuroblastoma Cells Through Neuronal Nitric Oxide Synthase.

The fruits of Trapa bispinosa (TB) and seeds of Trigonella foenum-graecum (TF) are used for their nutraceutical properties in various systems of traditional medicine practiced in India. In this study aqueous and methanolic extracts of TB fruits and TF seeds were prepared and their protective effect was studied on hydrogen peroxide (H2O2)-treated neuroblastoma (NB-41) cell line. Cell viability, nitric oxide (NO) levels, mRNA, and protein profiles were analyzed and compared with untreated control. Results show that aqueous extracts of both TB and TF provide significant protection to neuroblastoma cells with TF aqueous extract offering better protection through upregulation of neuronal nitric oxide synthase (nNOS) against hydrogen peroxide generated stress. This is the first report demonstrating protection of neuronal cell lines by use of TB and TF extracts through modulation of nNOS activity.

Rhythmic breathing: immunological, biochemical, and physiological effects on health.

Yoga and breathing techniques have become increasingly popular in recent decades. Sudarshan Kriya (SK) is a type of rhythmic and controlled breathing that involves cyclic breathing in which long breaths are followed by medium and short breaths. Scientific research has been conducted to study the effects of SK on different physiological parameters. Various studies have shown that the technique is simple and cost effective and can be used as a complementary therapy, together with ongoing conventional treatments, to help people suffering from extreme levels of stress, anxiety, and other physical problems. Studies have demonstrated that SK can play an important role in promoting a healthy lifestyle by improving immunity, antioxidant status, hormonal status, and brain functioning. Through available scientific evidence and research, the current article aims to review the complementary role of rhythmic breathing (ie, SK) as a practical and effective tool to alleviate stress, improve health, and increase wellness.

Nitric oxide blocks cellular heme insertion into a broad range of heme proteins.

Although the insertion of heme into proteins enables their function in bioenergetics, metabolism, and signaling, the mechanisms and regulation of this process are not fully understood. We developed a means to study cellular heme insertion into apo-protein targets over a 3-h period and then investigated how nitric oxide (NO) released from a chemical donor (NOC-18) might influence heme (protoporphyrin IX) insertion into seven targets that present a range of protein structures, heme ligation states, and functions (three NO synthases, two cytochrome P450's, catalase, and hemoglobin). NO blocked cellular heme insertion into all seven apo-protein targets. The inhibition occurred at relatively low (nM/min) fluxes of NO, was reversible, and did not involve changes in intracellular heme levels, activation of guanylate cyclase, or inhibition of mitochondrial ATP production. These aspects and the range of protein targets suggest that NO can act as a global inhibitor of heme insertion, possibly by inhibiting a common step in the process.

Oral vaccines: new needs, new possibilities.

Vaccination is an important tool for handling healthcare programs both in developed and developing countries. The current global scenario calls for a more-efficacious, acceptable, cost-effective and reliable method of immunization for many fatal diseases. It is hoped that the adoption of oral vaccines will help to provide an effective vaccination strategy, especially in developing countries. Mucosal immunity generated by oral vaccines can serve as a strong first line of defense against most of the pathogens infecting through the mucosal lining. Advances in elucidating the mechanism of action of oral vaccines will facilitate the design of more effective, new generation vaccines. There are promising developments in the use of different agents to effectively deliver the vaccine candidate. It is hoped that ongoing research may be able to set another cardinal point, after polio vaccine, in eradicating infectious diseases.

Thermal inactivation of protective antigen of Bacillus anthracis and its prevention by polyol osmolytes.

Protective antigen (PA) of Bacillus anthracis is the main immunogen of all anthrax vaccines. It is a highly thermolabile molecule and loses its activity rapidly when exposed to higher temperatures. Earlier some cosolvents had been used to stabilize PA with variable success but no study has been done to find out the primary cause of PA thermal inactivation. This study aims at elucidating the predominant cause of thermal inactivation of PA in order to develop more effective strategies for its thermostabilization. The prime cause for the loss of biological activity of PA at high temperature was its aggregation and an inverse correlation between PA activity and its aggregation on heating was observed. Inactivation of the protein by autolysis did not occur. This paper reports the use of a series of polyol osmolytes to stabilize PA. Different polyols stabilized PA to a different extent against thermal inactivation in a concentration dependent manner, with glycerol stabilizing to the maximum extent. Addition of NaCl to glycerol solution further enhanced the thermal stability of PA. An increase in the T(1/2) value, the temperature at which 50% of the activity is retained during short-term incubation, of more than 20 degrees C was observed. The half-life (t(1/2)) of PA thermal inactivation at 40 degrees C increased by more than 6 times in the presence of the mixture of glycerol and NaCl as compared to control. This study demonstrates for the first time that aggregation of the PA molecule is the predominant cause of its thermal inactivation, and can be very effectively prevented by the use of glycerol and other polyols to increase the shelf life of the recombinant vaccine against anthrax.

Expression of anthrax lethal factor gene by osmolyte induction.

The anthrax toxin consists of protective antigen (PA), lethal factor (LF) and edema factor (EF). PA mediates the entry of LF and EF to the cytosol where they exert their effects. Although PA is the major component of the vaccines against anthrax, LF has also been found to play an important role in enhancing protective immunity. We have developed an osmolyte-inducible LF expression system. The protein expression system contributed no additional amino acids to the recombinant LF making it suitable for the human vaccine trials.