I saw in another thread people discussing it. Some say it was USA, others say URSS. And what was the contribution of Brazil (with Osvaldo Aranha) in that matter?
There are two types of recognition: de facto and de jure.
De jure is a stronger type of recognition. De facto recognition entails understanding that a country controls an area. It doesn't necessarily derive its control from the law and being the right sovereign, but it is the one that is there in reality, and de facto recognition recognizes statehood as such.
De jure recognition means to recognize that, as a matter of law, the country in an area is the sovereign of that area.
The US was first to recognize Israel de facto, doing so within 11 minutes. The Soviets were the first to recognize Israel de jure, doing so within 3 days. The US would not recognize Israel de jure until the 1948 wars were virtually over, at the end of January 1949 (a bit over 8 months after its Declaration of Independence).
I'm unaware of major Brazilian involvement. Brazil gave Israel de jure recognition not long after the US did, about a week later. It skipped straight to de jure, and hadn't given Israel de facto recognition first. Brazil, along with 32 (out of 56 I believe) other countries, voted for UN General Assembly resolution 181 that would've created a Jewish state, on November 29, 1947. But that resolution was never implemented since war broke out immediately after, so the resolution was purely symbolic.