fold this river against unknown?

PokerStars No-Limit Hold'em, $0.10 BB (8 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

BB ($15.85)
UTG ($7.95)
UTG+1 ($9.95)
MP1 ($15.20)
MP2 ($4.15)
Hero ($9.75)
Button ($9.95)
SB ($7.85)

Preflop: Hero is CO with 7, 5.
UTG calls $0.10, 3 folds, Hero calls $0.10, 2 folds, BB checks.

Flop: ($0.35) 8, 6, 4 (3 players)
BB checks, UTG checks, Hero bets $0.25, BB folds, UTG calls $0.25.

Turn: ($0.85) J (2 players)
UTG checks, Hero bets $0.5, UTG raises to $1, Hero calls $0.50.

River: ($2.85) 6 (2 players)
UTG bets $1.9, Hero...

Do yourself a favor and fold everything but 22+ AK AQ AJ. open 4-6 tables and set farm. build the roll to around 400 and move to 25 nl, rense and repeat.