library(readxl)
error_bar = read_excel("C:/Users/Admin/Desktop/error_bar.xlsx", 
   sheet = "Sheet2", col_types = c("text", 
        "text", "numeric", "numeric"))
attach(error_bar)
require(ggplot2)
color=c("blue","black","pink","green")
ABC=element_text(color="black",size=9)
View(error_bar)
g=ggplot(error_bar,aes(x=Enzyme,y=Mean,fill=Treatment))
g+geom_bar(stat = "identity",position = position_dodge(width=0.9))+
geom_errorbar(aes(ymin=Mean-SEM,ymax=Mean+SEM),width=0.1,position=position_dodge(0.9))+
scale_fill_manual(values=color)+
theme_bw()+theme_classic()+
theme(axis.text.x=ABC)+theme(axis.text.y=ABC)