An Adelaide chef who defaced more than a dozen businesses in the CBD during a graffiti spree has avoided conviction, blaming his behaviour on a mix of prescription drugs and alcohol.

Key points: Barnes admitted to marking graffiti on 22 businesses in Adelaide's CBD in February

Barnes admitted to marking graffiti on 22 businesses in Adelaide's CBD in February He has previously told the media he is the nephew of Jimmy Barnes

He has previously told the media he is the nephew of Jimmy Barnes Barnes pushed over a reporter as he left the Adelaide Magistrates Court

Jess Alan Barnes pleaded guilty in the Adelaide Magistrates Court to marking graffiti on 22 businesses on Union Street and Rundle Street in the early hours of February 23, 2019.

The 39 year old has previously claimed in media interviews that he is the nephew of rock singer Jimmy Barnes.

The court heard Jess Barnes lost his job as a chef at Midnight Spaghetti on Grenfell Street as a result of committing the offences.

Barnes apologised in court for his actions, and told Magistrate Alfio Grasso that he was struggling with mental health issues and alcoholism at the time.

"I'm very sorry for what I've done, I'm prepared to pay full restitution and be held responsible for my actions," he said.

He said he had taken up urban art as a hobby and had the spray-paint on him because the day before he had painted a mural in Morphett Street.

However, he told the court he could not remember marking the graffiti or why he turned to vandalism.

Barnes pushed over a news reporter as he left court

Mr Grasso placed Barnes on an 18-month good behaviour bond and ordered him to pay $6,160 to cover the cost of removing the graffiti.

He urged Barnes not to consume alcohol with his medication, describing it as a "recipe for disaster".

"Regrettably he went to work … and can recall consuming at least 12 drinks, that on top of what I describe as heavy-duty drugs that were properly prescribed to him," he said.

"He is remorseful, I accept that he is, he was going through difficult times at the time.

"I'm satisfied that this was not a premeditated offence.

"This man has never been in trouble before, I need to give him credit for that."

While leaving court Barnes pushed over a reporter and grabbed the hand of another, before spitting on her microphone.