Calum Kerr said "every effort to explore any avenue" had been made to keep Burgons of Eyemouth open.
The company started consultation over plans to close the facility last month.
Spokesman Trevor Bartlett said negotiations with potential buyers had been ongoing and would continue for as long as possible.
Berwickshire, Roxburgh and Selkirk MP Mr Kerr said: "Unfortunately it does seem that despite discussions with the Scottish government, Scottish Enterprise, Scottish Borders Council and myself, the plant is going to shut."
He said the company "clearly felt it had to act to prevent further losses and possible insolvency".
He pledged to "pull all the stops out" to help workers set to be made redundant.
During attempts to save the factory, Mr Kerr managed to find savings of about Â£30,000-a-year with local farmers willing to use empty crab shells as fertiliser rather than the firm sending the shells to landfill.
"It would have been a helpful saving but unfortunately and despite all our efforts, it came too late," he said.
"The loss of Burgons is a severe blow to Eyemouth.
"We now need to do everything we can to make sure that these skilled and committed workers find new employment, hopefully locally and as quickly as possible."
Mr Bartlett said it was grateful to Mr Kerr for his efforts towards seeking ways of keeping the business alive.
"Unfortunately, though, there have been too many other reasons for the losses which have been supported by the parent company for three years, preventing its growth, so it has been with great reluctance that we have made this decision," he said.
"As the only company to offer continued employment when the previous owners were looking to sell, we feel we have done our best for the workforce and are confident that the employment opportunities are far better now than they were three years ago and we wish all the staff well as they seek other work."
An MP has said efforts to save a crab meat factory which employs more than 80 staff in the Scottish Borders have proved to be "in vain".