UPDATE 1-Bio-On shares plunge further as shareholders try to keep it afloat

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MILAN, Oct 2 (Reuters) - Italian bio-plastics maker Bio-on said on Wednesday its founding shareholders would provide money for a year to keep it in business as its shares plunged 10% after a 48% drop the previous day.

Bio-on, which has come under attack by U.S. fund Quintessential, on Tuesday reported a collapse in first-half revenues and slashed its full-year sales forecast.

Quintessential in July questioned the accounts of the Bologna-based company, whose customers include consumer goods company Unilever .

Bio-on said on Tuesday the fund’s criticism had hampered talks with customers to sell its PHA plastics technology.

The company said founding shareholders had committed to providing 10 million euros ($10.9 million) for 12 months to keep it afloat.

In a statement issued at the behest of market regulator Consob, Bio-on also clarified the reasons why EnVent Capital Markets had stepped down as its nominated adviser, a post required for companies listed on the alternative-investment segment of the stock market.

It said EnVent had walked away on Sept. 28 saying it had just cause to end the contract because of an alleged lack of collaboration and breach of trust. ($1 = 0.9151 euros) (Reporting by Valentina Za; Editing by Giles Elgood)