As far as I understand, the salt in pickling is both a preservative and an agent to assist the microbes producing lactic acid in the pickling process.

Yes... as said by @Thomas Nicol..

1. Salts act as preservative as it check the growth of decomposer/ harmful bacterial growth and also assist lactic acid bacteria.

2. As per my understanding salt act as osmoregulant in bacteria and thereby check bacterial growth.

3. The oil layer in pickle prevent the entry of oxygen, as it is required by all aerobic microorganisms. Here, oil layer having complementary effect on arrest the growth spoilage causing micro-organisms apart from increasing taste.

The high salt content in pickles used as preservative agent and prevent the growth of contaminated microorganisms..regards

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