<?php
 
$pt = [',', 'janeiro', 'fevereiro', 'março', 'abril', 'maio', 'junho', 'julho', 'agosto', 'setembro', 'outubro', 'novembro', 'dezembro']; 
$en = ['', 'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];
 
 
$data = DateTime::createFromFormat('d F Y', str_ireplace($pt, $en,'22 maio, 2018'));
echo $data->format('Y-m-d') . PHP_EOL;
 
 
$data = DateTime::createFromFormat('d F Y', str_ireplace($pt, $en,'30 março, 2018'));
echo $data->format('Y-m-d');

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