Search their website, check the indexing, the editorial board, their review process and download some papers they published and consider the quality of papers they accepted and published.After your checks and it is alright proceed with them.
First, you should clarify about "trusted journal". wht do u mean by trusted? that journal is a peer-reviewed journal like other springer journals and indexed by many scientific database like ISI, Scopus, ...
This Journal belongs to Springer and evidently Springer has one of the strongest STM and HSS eBook collections and archives, as well as a comprehensive range of hybrid and open access journals. Therefore certainly You can trust on it.
YES IT IS AROUND FOR QUITE SOME TIME AND COMES FROM REPUTED PUBLISHER- SPRINGER HENCE GOOD ENOUGH. PROVIDED YOU HAVE SOME QUALITY DATA TO SUBMIT YOUR MANUSCRIPT TO IT. BEST LUCK.
International Microbiology is a trusted journal. It is the official Journal of the Spanish Society for Microbiology.It is indexed in Thomson Reuters ISI, Scopus etc.
Why do you need others opinion. If you don't trust don't send any manuscript. You should not be influenced by other's trust.If I feel it is trusted, I won't ask for others view point to come to a decision as I have certain justification for my trust, which you may not agree and you have certain justification for not trusting. It is the personal view of every author which should not be accepted by every author.
As I said earlier, to decide the journal being trust worthy or not is solely dependent on you and it will be your personal opinion. Neither me nor Samy can ask you to have different personal opinion.