Alkalinity is characteristic of electron deficiency which is ideal condition for oxidation reaction.

Energetics of Oxidative Dehydration in cellular & sub-cellular Environment

It has been argued elsewhere that each ecosystem is charged with a certain quantum of energy (DE) comprising free energy (DF) and entropy (DS).

DE   =  DF  +  DS

All units in the cellular and sub-cellular environment that constitute the nanoenvironment and picoenvironment likewise contain energy stored in them. The free energy DF constitutes the driving force that performs work, while DS the entropy factor is non-available energy owing to the stresses created during work performance. A large share of DF the free energy and small share of DS, the stress factor in the system, including a molecular framework, suggests continuation of growth processes. Contrarily a large share of DS in situations where stresses are dominant, the driving force would face restraint and even reversal.

Increase in DF implies addition of free energy to a molecule which is then said to reduce the molecule. Likewise removal of free energy from a molecule implies increase in DS and is called oxidation. Reactions resulting in transfer of free energy from one molecule or one system to another are termed oxidation/reduction, or redox reactions. In a redox reaction one or more molecules is reduced (gains energy) while one or more molecules is oxidized (loses energy).

Life processes, like all others that involve work, require energy. Activities like muscle contraction, nerve conduction, active transport, growth, reproduction, as well as metabolism and catabolism of substances that are necessary for carrying out and regulating these activities, require an adequate supply of energy. Enzymes are responsible for reactions at cellular level for the transfer of free energy from one molecule to another. A typical enzyme is extremely selective for its substrates (the reactants). Enzymes bind substrates in such a way that they are brought in to positions favoring a particular reaction, greatly lowering the activation energy for the reaction. By controlling enzyme activity a cell can control reactions because the types of reactions catalyzed by enzymes are extremely unlikely to occur spontaneously.

The Eternal Laws state that spontaneous reactions occur in directions that increase the overall disorder or entropy of the universe. The same statement holds true for the ecosystem of the cells and their component subsystems in the nanoenvironment and in the picoenvironment. Here biochemical processes governed by Bioenergetics, described in detail with respect to virus-host cell interaction in a subsequent chapter, are responsible for the energy supply to living cells and for exchange of energy as a consequence of the operations in the nanoenvironment and picoenvironment. Accordingly with each energy transfer some energy is lost to commotion of molecules reflected by the entropy factor DS and is indicated in some cases by rise in temperature.

 Enzymes, while acting as catalysts also play a fundamental role in conservation of free energy; accordingly some energy is lost with each process although endothermic reactions use the energy in the ensuing reactions. The stepwise oxidation of substrates by enzymes can be thought of as cyclic processes so that available free energy is still retained in useful form in the nanoenvironment.

 Dr. Mirza Arshad Ali Beg

Former Director General PCSIR

alkaline pH does not really change the thermodynamics of oxygen reactivity, but does change the reactivity of the organic molecule being oxidized,

You can think of it in two ways: (1) during the course of oxidation, protons (H+) are usually products of the oxidation half-reaction (for instance: CH3OH + H2O --> CO2 + 6 H+ + 6 e–), so the reaction is favored under alkaline conditions; or (2) oxidation is the loss of electrons from a species, so a negatively charged species should be easier to oxidize than a neutral analog (pure electrostatics). If the alkaline environment is basic enough to deprotonate the substrate, the resulting anion should be much easier to oxidize.

These two examples demonstrate extreme ends of a spectrum: either oxidizing and then mopping up produced protons, or removing protons and then oxidizing. In reality both mechanisms play a role, and very often, protons and electrons are transferred simultaneously (or very nearly simultaneously). This is called proton-coupled electron transfer (PCET).

Ultimately it is the oxidative dehydration followed by reductive hydration.

Oxidation in life processes take place in alkaline conditions; remember blood pH is 7.2 to 7.4.

Thank You Mirza Sir for sharing in depth concept !

Thank you Bloomfield for your adding answer too

Several comments:

This is incorrect and inconsistent with basics of chemistry:

"Reactions resulting in transfer of free energy from one molecule or one system to another are termed oxidation/reduction, or redox reactions. In a redox reaction one or more molecules is reduced (gains energy) while one or more molecules is oxidized (loses energy)." 

This is incorrect:

"alkaline pH does not really change the thermodynamics of oxygen reactivity, but does change the reactivity of the organic molecule being oxidized,"

The redox potential of O2 (and numerous other oxidants) is pH dependent. 

"Oxidation in life processes take place in alkaline conditions; remember blood pH is 7.2 to 7.4."  I always thought that pH 6-8 is called neutral. 

This is absolutely wrong: 

"(1) during the course of oxidation, protons (H+) are usually products of the oxidation half-reaction (for instance: CH3OH + H2O --> CO2 + 6 H+ + 6 e–), so the reaction is favored under alkaline conditions;."

 The redox potential of O2 (and numerous other oxidants) decreases with pH. The thermodynamics of overall reaction CH3OH + 3O2 --> 2CO2 + 2H2O  is pH independent if you start from O2(gas) and end up with CO2(gas)

The answer to the main question, NO."With respect to oxygen molecule oxidation how alkaline pH helps in fast oxidation?" Oxidation by O2 could be pH dependent, but it's not obligatory, that the rate increases with pH

Thank you Geleti for adding  ur answer!

 Yurii V Geletti, Aaron Bloomfield, Mirza Arshad Ali Beg !

In most of the cases it is written that alkaline condition favored product formation,if the reaction is a oxidation reaction,then why so?

What about the acids that are being used as oxidizing agent?

If the pH is lowering then how it helps in oxidation?

If oxidation is independent of pH or independent of addition or deletion of H+ ions and  only depends on the compound that is used for oxidation and the compound that is going to be oxidized ,then how ammonia helps in oxidation?

Can you explain me with more examples,whether really alkaline pH affect oxidation or not?

Lopa, please provide the references to there you find the statement that "In most of the cases it is written that alkaline condition favored product formation,if the reaction is a oxidation reaction". 

The general statement is ambiguous. Oxidation reactions have their peculiarities. I wish to inform you that organic compounds like sugar alcohols are fast oxidized in acidic medium than alkaline medium.