The trailing comma after your list clause is allowed and indeed recommended, as it does not violate any rule of comma use and improves the readability of the quotation relative to the same text lacking the comma.
You should, however, endeavor to re-word to avoid, as the writing is relatively clumsy. But that's a stylistic choice, rather than a grammatical one. A simple fix would be to move the clause to either a distinct sentence, enclose the list in parenthesis or a subordinate clause, or move the second clause to the beginning of its sentence.
Examples of "fruit" are apples, pears, and bananas. But next to these, a lot of other fruit exists.
or
Next to common fruit (apple, pears, and bananas), a lot of other fruit exists.
or
Next to common fruit, such as apple, pears, and bananas, a lot of other fruit exists.
or
A lot of other fruit exists next to apples, pears, and bananas.